Milk

Kirkham’s Lancashire

The legend that is Graham Kirkham, in the maturing rooms.
The legend that is Graham Kirkham, in the maturing rooms.

‘What do you know?’ asked Graham Kirkham, on meeting me in the dairy.

‘Um – not much?’ I ventured. But I was about to learn a lot.

The really exciting thing about the Kirkhams, from my then perspective as a retailer and temporarily disadvantaged cheesemaker is that they farm only with their cheese in mind. They have no Dairycrest contract to fulfil, no minimum litres to achieve and therefore everything about how they farm has the goal of making amazing cheese.

Amazing cheese needs amazing milk but, specifically, it needs cheese-orientated milk. This means that it needs to have zero pathogens but viable lactic acid bacteria and good solids (fats and proteins). Graham’s cows are largely Friesian which would normally produce milk with about 3% fat. His cows manage 5% fat. For comparison that is Jersey milk levels.

They achieve this by specifically gearing the feed and breeding so that it suits the rhythms of the cheese. They stagger the calving all year round so that the milk is consistent in quality. End of lactation milk has different fats and proteins and tends also to have a higher bacterial load. Early lactation milk has a tendency for the fats to separate out more easily as well as also having a higher bacterial load. The more you can balance out these inconsistencies, the easier it is to make good cheese. The cows are fed silage all year round in addition to the pasture that they graze. In fact, last year (it was September 2015 when I visited), although they had free access to the outdoor pastures, the cows had been happier indoors where they have an airy barn with a back scratching brush roller. It had been monumentally rainy in Lancashire that summer. This meant they had eaten more silage than usual and the milk was more consistent.

Silage that the cows eat. The neatness, order and cleanliness of how it is stacked impressed me.
Silage that the cows eat. The neatness, order and cleanliness of how it is stacked impressed me.

The grass, being open to the air, varies. Variety can come from moisture content one rainy day to the next drier day as well as having higher sugars at the beginning of the season and more fibre towards the end of the season. When cutting grass for the silage, the Kirkhams wait longer than the average dairy farm. If you’re farming for milk production, you want fresh young grass, high in sugars and plenty of moisture. It’s rocket fuel for volume production. But if you’re looking at the solid content of the milk rather than the number of litres you’re producing, you’ll cut your silage grass later in the season when it’s more fibrous. This helps the fat percentage in the milk and is probably one of the reasons that the Kirkhams are able to make a Friesian herd give Jersey quality milk.

A couple of the Kirkhams cows in their comfy shed, eating away.
A couple of the Kirkhams cows in their comfy shed, eating away.

The reason they go to all this trouble with the milk is evident when you look at the way they make cheese. In the interests of achieving the correct buttery crumbling texture and slow acid development, they use tiny amounts of starter. For a vat of 2,500 litres milk they use milliletres of starter where a quicker recipe would call for 25 litres of starter or 1% of the milk volume. As a result of their starter use, they have a slow acid development, which helps the curd develop a richer, more nuanced, complex and subtle flavour that will develop over time. They mix the curd from 2 days production together when it comes to moulding cheeses so this slow development is what allows them to do this without compromising the flavour of the final cheeses. It is the traditional way of making Lancashire, dating back to when cheese would have been made without starter or at least using the whey from the previous day’s make as starter if necessary. Those were days in which cows, being milked by largely by hand, had more lactic acid bacteria in their milk so the need for starter cultures was reduced.

The cheeses are made over 2 days. On the first day, the milk is pumped into the vat and starter is added. They use a liquid starter, which looks like a runny yoghurt and tastes pretty delicious. The rennet is added about 20 minutes later, giving the starter time to acclimatise to its new medium but not develop appreciable acidity. The set is intended to take about an hour and, as they are practised hands at this, it does. The curd is then cut to the size of a hazelnut or roughly a 1cm cube. It is stirred briefly before it’s allowed to settle. Greater stirring would increase the acid production and create a bright and dry crumbly curd, which isn’t the mellow buttery, feathery texture Graham is going for. After about an hour, the free whey is pitched off and the settled curd is ladled into the centre of the vat, where the pressure of each new ladle of curd helps the curd-mass squeeze out whey.

Beginnings of the process of transfering scoops of curd from the side of the vat to the centre. Beginnings of the draining process.
Beginnings of the process of transfering scoops of curd from the side of the vat to the centre. Beginnings of the draining process.

When there are empty channels at every edge of the vat, the curd is allowed to bow out under its own pressure and then using a knife, blocks of curd are cut and stacked onto the curd mass continuing the whey expulsion. Finally a channel of curd blocks is cut into the centre of the vat and from then they begin to handle the blocks of squashed curd onto a cloth lined draining table. During this process, the curd has changed from a soft and jelly-like texture to something more akin to chicken breast. Once in the draining table the curd is broken by hand into pieces that roughly equal a handful of curd and then left to drain for an hour with the cloth wrapped around them and light weights placed on top to ensure the whey doesn’t stop draining.

Breaking the curd by hand in the draining table.
Breaking the curd by hand in the draining table.

The curd is broken again another 2 times during the afternoon with an hour’s wait in between each break. The time between curd breaks will then be used to combine a couple of days’ curd, mill it, salt it and pack it into moulds, which will form the final cheeses. It smells utterly delicious at this stage. In fact it’s one of the best jobs of the day, arm deep in curd that smells of lactic butter and, if you sneak a taste, tastes of salty, buttery gorgeousness.

Graham Kirkham prepares to mill curd from 2 days to pack into the moulds.
Graham Kirkham prepares to mill curd from 2 days to pack into the moulds.

A mixture of blocks of curd from yesterday and the day before are put through the curd mill to bring them down in size. Salt is then added and mixed by hand before the curd with salt is milled a further 2 times and then when it’s a fine texture, is packed into moulds and put into the presses overnight. The presses are tightened slowly with Graham doing the final turn at about 9pm – you don’t want to press the curd too soon or it might actually make the surface too firm while the interior retains its moisture. This would lead to funky fermented flavours as trapped moisture and naturally occurring yeasts go crazy together at a cosy temperature of about 20C. It’s especially likely to occur if you try and mix curd from 2 days as one lot of curd has sat for an extra day at ambient temperatures and without any salt to slow down yeast and bacterial activity.  This makes the yeasts sound undesirable and as long as they are controlled and in balance they certainly are not.  They are part of the natural flora of the milk after all.  The key is balance and control thus it’s important to keep an eye on the drainage and pressing of the curd.  Why bother with 2 day curd if it’s so much more difficult? The 2 day curd is important because it creates a mellow, buttery, savoury and complex flavour and this is something that sets the Kirkhams apart from other Lancashire makers who have opted for the faster and moister way of making cheese.  On the face of it, it makes sense commercially to have a shorter working day and a fast maturing cheese but then by following the slower and more traditional route, the Kirkhams have a unique and delicious cheese that is highly sought after.  Its popularity and the satisfaction in tasting the cheese alone justifies the considerably greater workload that it requires but because it is something special, Graham can also charge a price that means despite the slower maturation, greater workload and indeed resulting wage bill, he can make a profit.  This is the way of artisan cheese.  If you listen to conventional business theory, it makes no sense and yet if you stick to your guns and make something really good, it makes money.  Goes to show the limitations of what we normally see as business sense.

If Graham made a ‘more efficient’ cheese, the curd would be too wet to keep for an extra day.  If he tried to then it would taste eggy, sulphurous and so the quicker and moister recipe tends to lend itself to a simple one day curd cheese. This is fine but one dimensional and lactic , whereas the addictive quality of Kirkhams is that it has so much more than that.  A few days in his dairy and I learned about milk production, cheesemaking and had a beautiful illustration of the shortcomings of the standard business model.

Cheese Grading

Chris George, like me, also ex of Neal's Yard Dairy, sampling cheese on a tour of their maturing facility, back in 2009
Chris George, like me, also ex of Neal’s Yard Dairy, sampling cheese on a tour of their maturing facility, back in 2008 (thanks to NYD for the photo – oh yeah and Chris)

‘A Cheese Grating Course?’ asked more than one of my non cheese friends when I told them I was going to learn more about cheese grading.

‘No, GRADING,’ I replied, realising again that I have indeed entered the realms of cheese nerdery that doesn’t quite translate to the outside world. ‘That’s the process by which cheeses are evaluated either during maturation in order to determine which market they should be sold into (retailers, wholesalers, exporters) or also during judging at a cheese show.  You assess the cheese for texture, body and flavour and note down your observations for review later.’

‘You eat cheese all day?  Wow, my kind of course.’

Not exactly, but I must say it was a very pleasant way to spend the day and yes, cheese was consumed…in the interests of education you understand.

About a fortnight ago at the beginning of February, Julie Cheney hosted a day’s course in her house on the subject of Cheese Grading.  The course was being taught by Jayne Hickinbotham of Dee Dairy Services who is one of the UK cheese industry’s unsung heros.  After years in manufacturing with big creameries like Dairycrest, she went freelance and now operates as a consultant who can pretty much do anything from calibrate your thermometers to write your HACCP to train your staff in Dairy Hygiene to help you write up risk analysis justifying the more traditional of cheese techniques like use of raw milk and use of wood in maturation rooms.  She is also a trained RPA auditor and Cheese and Butter grader and until she stood down from it, was the Chief Steward responsible for the Cheese and Dairy Show at the Great Yorkshire Show.  As if that wasn’t enough, she co-wrote the Specialist Cheesemakers Section of the SALSA + SCA standard and is one of their Dairy mentors and auditors as well as sitting on the SCA’s Technical Committee.  She knows her stuff.

The course, which, to give it it’s proper name was ‘Sensory Analysis (Grading and Selecting) and Managing Variation of Hard, Soft & Blue Cheese’ was attended by a very interesting bunch of people.  Again, we left a cheese function with Rose remarking, ‘Cheese people are all so lovely!’

Our fellow learners were Julie herself, Paul Thomas of Thimble Cheesemakers, Ned Palmer (my ex colleague from NYD days and now a freelancer himself), David Jowett, Francis & his wife from Taste of the Vine who are thinking of taking up cheesemaking, Robbyn Linden from The Cheeseboard in Greenwich, Patricia Michelson and Sofia from La Fromagerie, Jonny Crickmore of Fen Farm Dairy, a couple from Lyburn Cheesemakers whose names I never got (sorry) and a Neal’s Yard Dairy triumvirate of Adam Verlander, Terry Warner and David Holton.  I hope that was everyone!  It was certainly all quite cosy in Julie’s sitting room.

Jayne began by explaining the purpose of grading and how it was different from tasting as a sales tool.  This is a topic that I know she feels strongly about from her experiences as judge.  If you are tasting as a sales tool, it’s ok to think ‘I don’t like that,’ or ‘I really like that’.  If you are grading, subjective descriptions like that only lead to arguments and get you nowhere.  Grading needs objective and descriptive records.

For instance, a grader might record: ‘metallic, acidic, sour flavour, weak body’.

A sales taster would be more likely to communicate: ‘Don’t like that much, metallic, acidic and sour.’

You can’t really argue with the objective description.  It is what it is.  You can however argue with the subjective one and by being subjective it’s more likely to put the manufacturer on the defensive into the bargain.

‘What do you mean you don’t like it?  I don’t think it tastes at all metallic.’  And so on.

An interesting point too was that Jayne even refined it down to the choice of vocabulary.  ‘Astringent’ for instance we discovered was something that some of us identified as bitter and others as tannic.  That means it’s not clear or objective enough for grading.

Remaining with vocabulary, we discussed the difference between ‘body’ and ‘texture’; body being mass, solidity, density and something you can touch while texture is formation of structure and is visible.  We talked about use of certain words and their associations during grading.  You don’t use the word ‘sweetness’ as a positive descriptor with cheese.  It describes a fault relating to whey retention or adding potassium sorbate as a mould inhibitor (in industrial block cheeses).

We covered analysis procedures and hygiene – including personal hygiene.  You can’t accurately judge flavours in the presence of strong perfumes and you particularly can’t if you’ve just used very perfumed handsoap.  This latter is especially relevant to hard cheeses where you don’t just taste the cheese but also hold the sample between your fingers and knead it to assess the texture.  Then you taste it.

‘Mmmm – tastes like…um…freesias???’

Jayne even warned us about the planning a professional grader puts into their packed lunch.  She once suffered by having packed an orange to eat and realised only afterwards that the smell of orange oil on her hands which persisted after handwashing was distracting her from the product she was grading.  Several further washes of the hands in neutral soap were required.

It wasn’t all theory though, we also had the milk drinking challenge.  Six different milks were poured out and handed out in a blind tasting.

First was the control: standard full fat milk from the supermarket.  It was, white and uniform in appearance with a buttery and slightly animal aroma, tasted slightly metallic but with a caramel note and was relatively weak in body.  Jayne pointed out that it left a slightly drying sensation in the mouth.  This, she explained, is very common in all milk sold in our supermarkets nowadays.  The milk itself will have been collected from the farms and then moved to the processing plant.  It will have been pumped at milking, then pumped again to fill the milk tanker, then pumped a further time to empty it into the silos at the processing plant.  The time frame for this can be 3 days before it is pumped through a pasteuriser and then homogenised.  During this time and especially with all the pumping going on, the fat particles in the milk are damaged, oxygenised and this drying mouthfeel is the very beginnings of what would become rancidity if it were butter.  It won’t get that far as milk because there’s relatively little fat and in any case it won’t be kept that long.  This is one of the reasons that organic unhomogenised milk tastes better.

Our second sample was slightly pinky off-white and smelled distinctly caramelised.  It had flavours of coconut, malt and caramel but was also more strongly metallic.  The mouthfeel was most definitely drying, more so than our control sample.  It was more viscous in the mouth as well.  This, we discovered was UHT.  The caramel flavours coming about because the milk is heated to 135C in which process the milk sugars, not surprisingly, cook.

Uht_Milk

Our third sample again was off white and smelled slightly of caramel.  It tasted rather odd, distinctly of vanilla and sugar and at the same time, watery.  The feeling in the mouth was powdery and drying and the body was most definitely weak.  Turns out it was rice milk – vanilla is added as a flavouring to make it palatable.

ricemilk

Sample number four was pure white and glossy, almost reflective.  It smelled yeasty and had a very distinctive taste: slightly salty, caramel, coconut and most definitely GOAT.  The mouthfeel was not drying – it was quite neutral – however the caramel was an indication it might be being pasteurised at too high a temperature.  This often happens with all animal milks we consume ‘just to be on the safe side’.

goat-milk

Sample five was cream in colour and smelled buttery.  It tasted very sugary, mineral and nutty.  It produced a definite drying sensation but was quite creamy.  This was soya milk which I normally find very difficult to actually swallow so it was a pleasant surprise – well as pleasant as soya milk can be which, frankly, isn’t very.

Soya Milk

Finally we came to sample six.  It had a creamy white colour, barely any odour at all and tasted mineral, salty and slightly sour.  The sensation in the mouth afterwards was most definitely drying.  Jayne ‘fessed up.  This was milk with dilute hypochlorite solution in it.  That is, milk with bleach.  You may be wondering at this moment if it’s safe to drink milk with hypochlorite in it.  In fact it is.  Hypochlorite and bleach work by blasting open the cell walls of the organic matter they come into contact with.  In that process the solution however breaks down into its individual components which are salt, water and chlorine gas.  The gas escapes of course so all that is left is water and salt.  The milk therefore was completely safe and largely unaffected in flavour.  I described it as being a little more salty than our control sample but not everyone did.

hypo

Just as we were about to ask Jayne, ‘If that’s the case with hypochlorite, how come you can end up with food that tastes a bit like bleach?’ she went on to say:

‘So hypochlorite in itself doesn’t taint, but you know sometimes when you make tea with chlorinated water, you get a bleach taste?  That is a reaction with the phenols in the tea.’

We’ve all, in our years of cheese tasting, encountered cheeses that tasted a bit chloriney.  This would likely be the same issue.  As the milk is broken down by its starters it releases phenols and flavour compounds.  Some of these can react with hypochlorite.

With our milk tasting over and a lot of information imparted, we had a go at ironing cheese and then stood up to help ourselves to lunch – a particularly tasty macaroni cheese Julie had hand crafted which was made all the more flirty by the addition of crispy bits of bacon and artichoke hearts.  Returning after lunch, we settled down to the serious work of grading sample of cheese brought by our fellow course attendees.  I didn’t get round all of them, but I happily made objective and descriptive notes on: St Jude (of course), Paul’s Little Anne & Dorothy, Jonny’s Baron Bigod (incredibly edible – in large amounts), David’s St Oswald (which I could also eat a lot of with alarming ease), Old Winchester, a lovely Gouda-esque cheese from Lyburn, David Holton’s experimental John Littlejohn and Innes Log.  Perhaps inevitably, however, given the quality of cheese on offer, assessments became less objective and more subjective.  We may have been writing descriptively but it was hard to stop the exclamations of ‘Wow that’s amazing!’ that seemed to crop up with every new cheese tasted.

Maybe, at heart, we’re all salesmen.

We live, We learn … About Lactics

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The herd supplying Neal’s Yard Creamery (also a herd with some Montbeliard influence) lining up to be milked.

As prospective cheesemakers working with a milk supplier usually do, Rose and I have been sending off milk samples for microbiological testing for some months now.  While we’ve had generally good results regarding absence of pathogens, I was taken aback to discover that we also seemed to have an absence of lactic acid bacteria…or certainly we had a lot less then we wanted.

‘Most milk in the UK now is not good for cheese,’ pronounced Ivan Larcher at one of my SAF courses, ‘It is dead milk.’

‘A little damning, surely,’ I thought.

Lactic, if my dictionary is to be believed, means ‘relating to or obtained from milk’. It derives from the latin ‘lactis’ genitive form of the word ‘lac’ or milk.

Doesn’t milk just HAVE lactic acid bacteria in it?

Well, apparently not always and if it does, 1 day in a bulk tank and they are not very happy bugs.

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One side of the milking parlour at Merrimoles Farm showing the stalls in which the cows stand, the pipework and the clusters below.
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For any of my non cheese industry friends reading this post. First off, well done for making it this far into a pretty cheese-geek technical post and good luck with the rest of it. This, should you be wondering, is a cluster and it goes on the cows udders.

Our milking system is like most in the UK Dairy industry.  It has a series of clusters along parallel milk pipes.  Vacuum pumps pulsate to remove the milk from the cows udders and it is piped out of the parlour, through a filter, then a plate cooler and finally into the bulk tank where it’s held at 4C until the lorry comes from Dairycrest to collect it.   They come every 2 days and collect 4 milkings.

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The Bulk Tank.

When we test, we take our samples from the outflow pipe of the bulk tank.  We also send off the milk filter from the last milking which the lab immerse in water and then test the rinsate.  We don’t know anyone else testing the milk filter so when we got our first set of results back and discovered literally millions of bacteria on it, we didn’t know whether this was normal, really bad or even really good.  We certainly knew that millions of the little critters looked pretty alarming on paper.

Our bulk tank milk samples seemed to show a happy grown of Pseudomonas (we don’t want happy Pseudomonas) and a rather less happy growth of Lactic acid bacteria.  The milk filter results seconded this.  In the autumn, we called Ivan back for advice and subsequently did a big clean through using peracetic acid.  Following that we have used a weaker peracetic acid solution for the final rinse of our pipework.

To start off 2014 in the way we intended to continue, with some more testing.  This time, we were hopeful for better results and to be a bit flirty we were going to get Andrew the kindly milker to hand milk a couple of cows for us to see how they compared for lactic acid bacteria.  These cows were a black and white cow that looks more Friesian Holstein in appearance who goes by the name of 266 and a brown and white one that looks more Montbeliard in appearance with the name 258.  266 was docile and calm when milked.  258 was disconcerted not to be in her usual clusters and stamped about a bit. We could identify the test results later because Andrew got less milk from her before asking if he could give up.  The cows that were hand milked were only given a dry wipe to their teats before milking.  Normally when they are milked into the parlour, their teats are given a wash before the pumping starts.  It has reduced the total bacterial counts of the milk right down but rather unfortunately we think it may be washing off our lactic acid bacteria.

The bulk tank contained 3 milkings at this stage.  The fourth was about to take place as we tested and Dairycrest were due that night to collect.   The milk filter was from that morning’s milking.

The samples were posted, results duly came back and we emailed Paul Thomas for advice and guidance in their interpretation.

RESULTS:

Milk:

The bulk tank results were better than we’ve had at other points in the past in terms of Pseudomonas.  Before now we have had counts of 21,000 per ml of milk.  This time we had a count of 170 per ml.  However it did show us some staph aureus too which is less than ideal.  According to our lab (Microtech Wessex) we would hope to see around 80% of the total bacterial count being lactic acid bacteria and unfortunately still on this sample it is considerably less than that.  With a total count of 53,000 total bacteria per ml of milk, this would mean we’d like to see 42,400 of these to be lactic acid bacteria.  According to the test result there are 1,200.

The hand milked samples were very different one from the other.  No 266, the black & white cow’s sample was extremely low in everything.  Almost nothing grew on the lab plates according to the lab.  Its counts are 0 in everything except yeasts.  So it has no coliforms, pseudomonas or staph aureus but unfortunately no lactic acid bacteria either.  I imagine Dairycrest would love it.  For making cheese it isn’t ideal.

No 258, the brown and white cow’s counts however were about spot on what we want.  It had a total count of 8,800 total bacteria which isn’t huge.  However, according to our ideal 80% we would be hoping to see around 7,100 lactic acid bacteria and we have 7,040.  There are 10 yeasts which is good, no Pseudomonas, no Staph aureus.

The two cows results, while interesting and raising a few interesting ideas, thoughts and questions only really give us a snapshot of the milk of 2 animals.  Importantly, though, it does show us that we have got the right balance of lactic to everything else in some of the animals in our herd.  Interestingly, Paul suggested that according to some of the papers he has read, the animals that line up to be milked first, being in general the livelier and healthier animals of the herd, often have lower somatic cell counts (an indicator of health) and as a result often have higher amounts of lactic acid bacteria.  If, as we are planning to do, we take our milk from the animals that are milked first, not only will we be using the pipelines at their cleanest but we will also be getting milk that is better suited to our cheese.  In addition, we will be taking the milk away without it being cooled.  This makes sense from an energy standpoint – why cool it to heat it back up to 38C – but also allows the lactic acid bacteria to compete with the Pseudomonas.  Cooling the milk to 4C and then storing it at that temperature for 36 hours has stopped the small numbers of lactic acid bacteria growing and reproducing but at those temperatures, the Pseudomonas can still grow.  According to survival models Paul referenced we could probably knock that 1200 per ml down to 120 just due to the storage time at cold temperatures.

Milk Filter:

The Milk filter results have always looked rather alarming to us in terms of Pseudomonas.  But corresponding with Paul Thomas meant he helped us by analysing the results so that we can compare them more easily against our milk results.

The relevant results are (per filter):

  • 1,500,000 Pseudomonas
  • 10,000,000 Enterobacteriaciae

So – big numbers.  But, as Paul said, we have to interpret them based on the amount of milk that has gone through that filter.  The most recent milk report I have from the farm dates back to December but if levels are similar to those in December’s monthly report, we are looking at 120,530 litres of milk for the month.  This means a daily total of 3,888 litres.  Each milking there’s a new milk filter so while I expect there’s a difference in quantity between morning and evening, for the sake of mathematical ease, let’s say half of that quantity is applicable to our filter tests: 1944 litres.  1944 litres works out at 1,944,000 ml which has gone through the filter.

Assuming the filter removed 50% of our bacteria, this then suggests that before filtering the total quantity of milk (all 1,944,000ml of it), it contained:

  • 3,000,000 Pseudomonas.
  • 20,000,000 Enterobacteriaciae

So per ml of milk we have

  • 1.5 Pseudomonas and
  • 10 Enterobacteriaciae.

Which makes it all look rather a lot better.

Even if we assume the filter only removed 10% of our bacteria, this still suggests that the levels in the milk weren’t huge.  If that were the case, we’d be assuming pre filtration numbers of:

  • 15,000,000 Pseudomonas
  • 100,000,000 Enterobacteriaciae

So per ml of milk we have

  • 7.7 Pseudomonas
  • 51.2 Enterobacteriaciae

However this doesn’t take into account the fact that the filter had been in the parlour during the day and we didn’t have fully frozen ice packs in our insulated box.  The sample was 10C when it was tested and apparently we can knock at least a couple of zeros off our total counts on the filter based on the time it had rested at that temperature since milking and whilst being posted to the lab. All of a sudden, this makes our Pseudomonas and Enteros presence not alarming at all.

THOUGHTS, CONCLUSIONS:

Pseudomonas:

The reason the bulk milk samples have been high in Pseudomonas in the past is that they are able to grown at 4C whereas lactic acid bacteria aren’t.  If there aren’t that many lactic acid bacteria in the milk in the first place and even on our brown and white cow friend 258, there weren’t huge numbers then the bulk tank is the worst conditions for them to grow and the best conditions for something that is happier at cold temperatures to get a head start.  Lactic acid bacteria like a range of temperature around body temperature basically but can grow from 20C – 50C.  So the bulk tank is giving an advantage to the wrong bacteria for cheesemaking.  In other words it is entirely worth it to arrange for the pipework we are planning and have our cheesemaking milk taken off before it goes through the plate cooler, and not just because of the energy use considerations.

There is still the cluster wash and some of the pipework which remains a concern as it will reduce lactic acid bacteria and potentially if there is doubt about the cleanliness of the water, will add in pseudomonas and possibly listeria.  In order to investigate this, we need to do a further milk test or water test.  I don’t know if it’s at all possible for the cluster wash to be switched off ever?  I am imagining not but it’s worth asking.  For the cheesemaking, it’s all about balancing the lactic acid bacteria against the pathogens and spoilage bacteria and the better we preserve the lactic acid ones the less we worry about the others.

Staph aureus:

The test results on this occasion aren’t hugely helpful but they basically indicate that they are present in the bulk tank and passing through the milk filter.  Evidently they aren’t present on every cow as there were none on either hand milked cow.

Paul Thomas’s theory based on some studies he has read (but I’d have to ask him if you wanted to know which ones) is that the animals that line up to be milked first tend to be the more vigorous, healthier ones which will be less likely to have Staph. aureus infections even at a subclinical level.  The less healthy ones will lag behind.

This suggests that our idea of taking the first bit of milk that goes through the milkline is probably a good one from the point of view of getting milk that is better suited to our cheesemaking.  Interestingly the animals with lower somatic cell counts (according to Paul), also tend to be the ones with higher counts of lactic acid bacteria as well.  Again, I’d have to push him for which papers supported that theory but it seems to indicate again that we will get more suitable milk for the cheese if we take the first lot of milk rather than from later in the milking.  Which means I will be getting up bright and early to collect.

A possible thing we could investigate as well is to look into the mastitis records to see if there are any patterns.  Paul (again) has had previous experience where with his milk supplier’s animals each cow that developed mastitis got it on the same quarter for a whole 2 week period.  It turned out that there was a contaminated rubber on one of the clusters.

Lactic Acid Bacteria:

The hand milk results do show that on individual animals we have pretty much perfect milk provided we can then manage the process so that we can get hold of that.

There’s no scientific basis for this that I know of but it’s a commonly held opinion that Friesian Holsteins are not as good producers of lactic acid bacteria and other breeds like Montbeliard are better.  Interestingly our results showed the perfect milk from a brown and white cow that Andrew felt would have more influence of Montbeliard in her genetics.  I don’t know how true that is however and it’s something to try and find out more about.

By taking milk from the livelier, healthier first milkers and keeping that milk warm we’ll give the growth advantage to the lactic acid bacteria as well as the other organisms.  Conventional wisdom sounds a loud klaxon at this point and shouts

‘What about growth of pathogens??? Re-frigerate!! Re-frigerate!’

And were it in isolation with no lactic acid bacteria, they’d be right to be cautious.  But by keeping the milk warm we are giving our lactic acid bacteria an even chance to consume that lactose and reproduce.  Then, when we add our starter cultures into the mix as well it should mean that lactic acid bacteria as a proportion of the total bacteria as we start to make cheese, out competes any pathogens or spoilage organisms.

The hand milking results also reassure us that the milk when it hasn’t gone through the cluster wash system does have enough lactic acid bacteria in it to try the experiments of making our own starter cultures from the milk.  This has always been an aim of ours which we thought we would have to postpone for a year or so at best but now seems much more possible.  It is, however, a discussion for another day and will involve a lot of hand milking and some careful selecting of suitable cows.

So, at the end of a rather head-hurting few days of analysing, emailing and thinking very hard, it’s good news.  We can try out making starter – hooray!! Obviously we won’t be using it unless it passes micro testing but for a while it didn’t look like we’d be able to even try.

It’s also a new list of questions to research.  Do the brown and while more Montbeliard looking cows like 258 give us better milk for our cheese?  Do the black and white cows have less lactic acid bacteria?  Does it all relate to their Somatic cell count levels?  Does the cluster wash still remove too many lactic acid bacteria and can there be an alternative?  If we can hand milk cows to make our own starter, does that matter?  And so on and so on.  Then there’s an off the wall ideas that Paul suggested too.  There are some studies in humans indicating that before giving birth, the nipple duct microflora is influenced by apparently deliberate movement of bacteria from the gut to the mammary gland by dendritic cells.  Perhaps this happens in all mammals and may account for the transfer of lactic acid bacteria into the baby’s and calf’s stomach with colostrum?

Who knew milk could be this complicated and this fascinating?  Just as well I never wanted a quiet life.

Studying Up on Milk

This year, at Slow Food’s Cheese, I noticed a new development that for once I had time to take advantage of, workshops on milk production.

I’ve been going to Cheese every year since something frightening like 2003 as part of the Neal’s Yard Dairy contingent.  Consequently my time has been spent on retailing, resting, staying up late eating pizza at Da Ugo or in club Macabre (when it still existed) and then necking strong but delicious coffees the following morning.
This time, however, I was here with purely the aim of furthering my cheese education.  Where better to comparative taste Gorgonzolas and Taleggios?  Where better to explore the concept of what a traditional recipe or make actually tasted like in the interests of developing the recipes I’d been trialling at the School of Artisan Food? Where better to learn more about cheese?  To which end, I trawled Slow Food’s website for tastings and discovered the milk workshops.
I’d helped Randolph Hodgson prep some of his own talks at Slow Food workshops in the past which were purely cheese focussed and with an element of pairing wine / beer etc and cheese.  I’d found them interesting but not hugely technical (not a reflection, I should explain, on what Randolph talked about – he was easily the most technical person there, it’s the other speakers who were a bit more pedestrian).  The milk workshops held in the piazza XX Settembre were more technical sounding, geared towards cheesemakers and milk producers and while there were some things that I didn’t feel the need to attend (a talk on adulteration of food and labelling regulations didn’t thrill me), there were some that were most definitely relevant.
The topics I thought it was a good idea to get clued up on were: animal welfare, the importance of pasture, milk quality that goes beyond simply whether it is raw or pasteurised, sustainable agriculture and the role of fermentation.

A white board displayed around town with loads of technically useful cheese facts and recipes on.  Just there for you to copy and to spread the cheesey knowledge.  This sort of generosity of information in the interests of the bigger picture is typical of Cheese.
It lead to a hugely interesting few days and a lot of food for thought and luckily for me, the happier the cows, bees and environment it would appear the happier the cheesemaker.  Let me elaborate:
The talk on animal welfare with speakers from Compassion inWorld Farming started by stating that animal health and human health are linked and animals farmed in a higher welfare manner produce better milk.  There are obvious examples of this:  animals on pasture have less instances of mastitis and cleaner udders than animals that live indoors.  To put it bluntly, in the fields, if they need to defaecate, they just walk away from it and to a nice clean bit of pasture.  In the sheds they can’t do that and although their bedding will be replaced frequently during the day, there’s more than just a chance that they will end up lying down on dirty straw at some point.   However, it goes beyond cleanliness.  The milk from animals that are grazed on pasture has been found to be more healthy with better levels of Omega 3 fatty acids and betacarotene.

The talk on pasture discussed milk composition in more detail, citing EU funded research projects that have demonstrated the effects of each different herb or grass or wild flower variety that the animals graze on the composition of the fats and the number of flavour ethanols in the milk and also its vitamin content.  One speaker, Roberto Rubino from ANFOSC (the Associazione Nazionale di FormaggiSotto Il Cielo), had particularly interesting data to demonstrate the different fatty acid composition between animals eating oats, borage, hawthorn (really), wild geranium and plenty of other plants.  His point was not that there was any one plant that was the cow / goat or sheep superfood but that the bigger variety the better.  Just like humans, a varied diet is better for the animal but we are able to reap the benefits of that through the composition of the milk.  He went on to also explain that the animals’ diet also affects the cholesterol in their milk.
Contrary to the thinking on nutrition that I remember growing up which had us ditching butter in favour of margarine and believing all cholesterol to give us heart attacks, current thinking now considers cholesterol a necessary part of the diet, provided it is not oxidised.  A diet of pasture contains 4 or 5 times as many antioxidants as the diet of animals on a zero grazing indoor farming system.  In other words, they consider that you can drink milk and eat butter and cheese without worrying about heart disease, provided it’s farmed a certain way.
A speaker also from the European Forum on NatureConservation and Pastoralism explained that the value of mountain pasture is precisely that it hasn’t been planted or farmed.  As a result, the plants are far more diverse than they would be even if planted with the most complex herbal seed mix.  They quoted that an intensively farmed and planted field would contain 2 or 3 different species whereas you’d expect to find 50 to 100 species in natural grasslands. They even explained that animals left to graze and pick and choose will even eat shrubs and leaves off trees sometimes for a bit of variety (presumably hence the hawthorn research presented by Roberto Rubino).
During the talk on raw milk, a speaker called Tom Baas a biologist from the Research Institute of Organic Agriculture in Germany (FIBL)talked about how research into raw milk in the past 10 to 12 years has shown a change in attitudes to unpasteurised dairy.  Statistical research demonstrated that raw milk could actually assist in children developing a healthy immune system and lower incidences of asthma, allergies and even hayfever.  Some of these points were rather circumstantial evidence, farmers children seem to be healthier than others, however, Basel University has done over 10 studies into the possibilities of raw milk against atopic conditions and other health benefits including that of a fatty acid called CLA (conjugated linoleic acid).  Their studies showed that CLA which is produced by herbivores will be different depending on the animals diet.  When fed to rats, the grass fed CLA did not make the animals put on weight or develop fatty liver while the CLA from animals on a different diet did.  CLA is present in raw and pasteurised milk but the heating process will affect it and at least make it less effective if not actually contributing to weight gain actively.Further to this taste studies had been carried out also assessing the smell, taste, aftertaste, viscosity and visual aspect of 4 different milks, 2 of which were organic (1 actually biodynamic) and 2 intensively farmed.  While the differences were subtle, a distinct difference was found.
The message of all of this?  Raw milk, varied pasture that is left to grow as naturally as possible, grass fed as much as possible will be the healthiest dairy food for you and will also have the best flavour potential for the cheesemaker.  Of course they were speaking in fairly black and white terms and you’ll find conscientious extensive farmers who do feed concentrates and silage who also manage to give their animals a varied diet while not using natural and unplanted grasslands.
Finally we moved to the role of fermentation.  This was an idea I’d first heard proposed at courses that Ivan Larcher teaches.  You have this amazing milk, with wonderfully farmed animals and all those aromatic flavour ethanols waiting to be liberated.  How to make the most of it? Well using a naturally fermented starter.  Just as the natural grassland is more diverse, so is the naturally cultured soured milk from your raw milk.  Most commercial starters will contain possibly 1 or 2 different organisms.  The more complex ones perhaps 4 or 5.  Your own natural culture from your raw milk will have many more and also all the ripening cultures too (yeasts and moulds).  It also renders your product truly a local and unique one.  The speakers gave a brief method for producing your own soured milk starter, something they called ‘latte inesto’ and tasted a range of 4 cheeses chosen to demonstrate that the latte inesto starter produced the more complex flavour.  Again, I’ve done enough tastings to know you choose your cheeses to demonstrate the point you want them to make so while the tasting was dramatic, it was also staged to be so.  The difficulty of naturally occurring bacteria is that you can’t be sure of what will grow, but if you have followed certain guidelines you will maximise your chances of cultivating good starter cultures rather than a big bunch of spoilage bacteria instead.
Most interesting for me, as we research our milk at Nettlebed, was the discussion on where the natural lactic acid bacteria come from.  The research in this case has not been carried out on dairy animals but on humans but it is extrapolated that other mammals will have similar processes.  The baby’s gut is populated with the appropriate bacteria by the colostrum phase but after that is finished, the milk produced is sterile.  Any lactic acid bacteria and other flora that get into the milk from that stage onwards are transferred from the skin of the udders which will be picked up from dust particles on their food and in the pasture, dust particles from the soil (this would be bad news things like E.coli and Listeria) or illness which would be mastitis (Staphylococcus aureus).
Further to that, a cheesemaker asked a question.  He had been making cheese with latte inesto for 20 years but recently in response to demands from the milk dairies he had been trying to reduce his total bacterial counts.  Ever since the counts went down, his latte inesto stopped working.  It wouldn’t sour and when cultured, the only thing that grew was coliforms (gas producing bacteria from the gut – harmless but no help to the cheesemaker).  It appeared that in pre-dipping the animals’ teats before milking, they were removing a healthy population of lactic acid bacteria and although there were very few coliforms present, in the absence of any competition, these became dominant.  By trying to clean up what had been essentially clean milk before, they had created ‘dead milk’.  The advice was to stop pre-dipping and do all they could to ensure lactic acid bacteria got back onto the teats (this can include wiping with hay before milking, making sure the animals are getting hay or natural grass as pasture) to make the milk come alive again.
In summary, what did I learn?  Well to sum it up in one sentence: diversity, diversity, diversity and leave it to nature as much as possible.  Naturally managed grasslands and animals kept as close to their natural state as possible will produce happy animals giving milk that is better both nutritionally and in flavour profile and potential.  Then allow your naturally produced milk to sour with what nature in its bounty has given you and you’ll get cracking good cheese!  In theory anyway….
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The Mystery of the Non-setting Sheeps Curd

After a summer and early autumn feeling like I got to grips with making some pretty good cheeses, the late season milk has thrown me a curve ball.  A lot is talked about seasonality in rather hazy, romantic terms of the terroir and what grasses or herbs or clover is available during the summer versus hay or silage in the winter.  Or even slightly more scientifically in terms of levels of fats and proteins in late season milk.  Very little, in my experience, is talked about in terms of temperature.We have recently had a head spinning turnaround from milk that set quickly and firmly (which we put down to high solids) to milk that just isn’t setting.  Fats and proteins aren’t dramatically different from the fast setting curd milk, there may be a little less calcium in the milk due to the grass quality not being what it was but basically that doesn’t seem to be the key issue.  Temperature.

For starters, the milk that had been arriving in the dairy at 27C or more in fact earlier in the year is now about 18C or 19C.  There are less sheep milking as more of them are served and those that are milking give less and less milk.  The body temperature of each sheep and the temperature of milk coming from each sheep hasn’t changed, but other factors mean the milk is much colder.  The sheep are milked before the cows.  The pipework is cold in the mornings now as it’s autumn and in addition it’s dark when the milking starts so what sun or daylight there is has had no chance to raise the temperature of the air or surroundings.  The milking system works by accumulating about 8 litres milk in a jar and then pumping it through into the dairy.  However it now takes longer to accumulate the 8 litres allowing the milk longer to cool as it does so.  It’s then pumped through cold pipes into the dairy.

Then there’s the room temperature or really to put it more accurately, drafts and currents of cold air.  If you look at the thermometer in the room the temperature hasn’t dropped massively and the heaters are going full blast and turned up as high as they can be.  However in the corridor where we do the packing the temperature is quite a bit colder which means that at this time of year, doors need to be closed to preserve the temperature in the dairy.

In the past couple of weeks the milk has gone from setting a bit too quickly because of its solids to setting very very slowly. Thinking back, the last of our fast setting milk was also at a point when the days were a little longer and then there was the brief Indian Summer when everyone went to the beach in October.  As the weather broke, the setting problems begain.  In looking at why this is happening (largely to me but it has happened to Martin too) we’ve looked very closely at the different ways in which temperature affects what we’re doing and how without us actually changing what we do, the parameters have entirely altered just because it’s autumn and we have less milk.

1. The milk is colder.  Any time it is left standing before the starter goes in, used to be a brief period of pre-ripening time as it was at 27C but very little is happening at 18C.  The lactic acid bacteria activity from the milk itself and from the starter once added is less even if the milk is heated and the starter added at around 31C because where there was a pre-ripening period, now there isn’t.  This in turn affects the quality of the set because the beginnings of acidification would free up a certain amount of calcium ions from the milk which helps for a good set and increases the yield.

2. The milk needs to be warmed up much more slowly and consistently.  To heat quickly, using the ‘flag’ or mini radiator type thing we use to warm milk (it works by running hot water through it) and stir the hot milk in, means it loses temperature more quickly.

3.  Even warmed more slowly, the milk doesn’t keep its temperature in the same way because there’s much less of it.  Whereas with quantities like 70 or 80 litres, the milk might drop 1 degree between adding starter and then adding rennet an hour later, it can now drop 2 or 3 degrees.  Losing temperature more easily again of course means the set will be weaker.

4.  The top of the curd, where you usually test the set, is colder than the lower part of the vat as it’s the area that’s open to the air the most.  Often this will set more weakly than lower down the vat.

Even by increasing rennet and trying to keep the vat next to the dairy’s heaters at all times after it’s been heated, the set just isn’t as strong as it has been.  The implications of this on the cheese are pretty huge.

1.  Weak curd forms a more sloppy substance going into the cloths.  Small and more mushy particles of curd clog up the cloths and reduce the effectiveness with which they let the cheeses drain.

2. Weaker and colder curd drains more slowly anyway.  It doesn’t free drain in the same way.  More cloth pulling only has a limited effectiveness as the cloths are clogged up already and also because with a weaker structure you end up losing fats and squashing the nutrients out of the curd by using more force but still finding that it feels soft and wet in texture.

And the effects of the weaker curd on the drainage cloths are:

Badly formed rinds because they are largely formed from the soft particles that collected on the cloths.  When salting or maturing further, these rinds are loose, too moist and come away from the cheese.

Cheeses that hold free moisture.
That old enemy we’ve been fighting with our draining cloths!  Because the cloths are clogged up, hindering drainage but also because the curd didn’t have enough resistance to the cloths to force out the free moisture when they were pulled up tightly and in the end slightly collapsed under the pressure we have floppier and less stable cheeses when they are turned out.  The effect of this is that the cheeses do not mature in a stable manner.  They don’t retain the calcium which will allow a full and elastic breakdown and they develop what is more of a lactic cheese texture with a very runny breakdown just under the rinds and a curdy, moist, acidic centre.  It’s not that this is unpleasant to eat, in fact it can be very tasty, it’s just not what we want.

Before I began making cheese, I might have tried to explain this to a customer by saying that at the end of lactation with the milk composition being different and the pasture being different, the cheese would change.  Having made cheese for a few months, I would now tell it very differently.  The biggest change has been the temperature.  So much for terroir!

Enter the cows

On returning from Piedmont just under a month ago, I checked Facebook to see a post from Nicola about 2 new additions at Holker Farm.  While this could have been puppies, pigs or donkeys, I was fairly certain that it was the much anticipated Shorthorns.  I was right.

One of the ladies, in the barn, with a curious sheep to the left

My first day back in the dairy was the first morning milking and they yielded us probably about 30 litres milk.  Since then they have settled happily in to their once a day milking regime and I’d say in the last week we’re getting nearer to 60 litres.  Nicola has been taking advice on their feed, switched the cake they get in the evening to a better quality and more nutritious one and given them a mineral lick all of which have contributed to them producing more milk but also milk with what seems like good solids.  Otherwise their diet is largely hay based and not particularly intensive.  They came in looking a little thin shortly after giving birth but are gaining condition and seem to be doing well on their once a day milking regime.  Not too taxing and yet yielding us plenty of milk and having now worked out a more regular size, we’re making roughly 10 cheeses weighing about 500g (probably) per day.

When I first started at Holker, Martin talked about how particular sheeps milk is and how once you get used to it, you’ll look at cows milk thinking, ‘What’s wrong with this milk’.  It has to be said I wasn’t entirely prepared for just how different the 2 milks would be.  The difference is (and was) perhaps heightened because the sheeps milk is end of lactation milk so the solids are huge – 8% fat and over 6% protein on one recent test.  The cows milk is early lactation and just naturally has much lower solids anyway than sheeps milk.  The first obvious difference however is the colour.  Cows milk is more yellow but at the same time more translucent, sheeps milk bright white and just standing until the end of the milking, there is a thin layer of yellow cream on top of the vat containing the cows milk.  The colour difference remains throughout the make as well, the whey is clearer and more yellow when cutting the cows milk, the sheeps milk whey, while a yellow colour is slightly thicker and whiter.

Cows milk curd after cutting
Sheeps milk curd after cutting 

The texture is very different too.  In fact it was tricky working out when to cut the cows curd in the first couple of days because the set is much more delicate.  After a couple of days we felt it was going to naturally need more rennet than the sheeps milk and have managed to achieve a firmer set as a result.  However when looking for the ‘clean break’ when determining when to cut the curd, the set of the cows milk when it breaks cleanly is a lot more jelly-like than that of the sheeps milk which is dense and robust.

Drainage is hugely different too.  Whereas the St James needs regular cloth pulling and done pretty forcefully at that, the cows milk cheese (current working name Feallan from the Old English for Fall i.e. Autumn) needs cloth pulling largely much more gently and rather than forcing moisture out, you’re just trying your damndest to keep up with the natural drainage of the curd.  Where St James needs to sit overnight in its cloths with a follower on, by about 3pm Feallan has been turned once in its cloths and ready to be turned again and taken out of the cloths.  In future we’ll get followers to be put onto the Feallan too but for now, they just drain without pressure overnight which leads to slightly less reliable shapes but the drainage seems to happen ok.

Early batches of Feallan and St James on Day 2 in the hastening room before salting.

As for maturing, well we have a couple of batches that we tried binding in spruce cambian (the leather textured layer below the bark that is used to bind Vacherin) which Martin set off into the Holker Estate to cut off trees in their timber stores.  More recent batches have been left to mature without and when we can compare and contrast the matured cheeses, we’ll get an idea of which tastes best.  Currently though, they are being washed a couple of times a week until they are roughly 2 weeks old by which time they have a reasonably convincing covering of B. linens and then they are being wrapped to continue maturing in paper.  Next Tuesday, Bronwen and David from Neal’s Yard Dairy will come and visit the farm and we will get a chance to try some of the older cheeses with them.  The cheeses will be about 5 weeks old by then and some of the oldest have a nice breakdown already.  It will be very interesting to hear what they think.

How do you cook?

As the milk amounts decline (the tups went in last week and half the ewes are now served), I’ve been thinking back to when I started making cheese in April and how the way we make cheese now has changed.The biggest change is that we’ve slowed the recipe right down.  Whereas we were heating the milk up to achieve a set time of an hour and then having to work the draining cloths hard to get the free moisture out of the mass of curd bits, we’re now getting a set time of more like an hour and a half or longer.  We’re not heating the milk as much now.  In fact I’m not heating it at all.

I do take the temperature of the milk when the starter goes in and from that, I’ll work out (in a slightly guess-work style it has to be said) how much rennet I want to add to get the set time of an hour and a half.  Sometimes this works out and sometimes I get it wrong and it goes slower than that but, on the whole, it does seem to work out that if the milk is around 27C then 1ml rennet to 5l milk seems to be the right quantity.  If the milk is warmer, say around 30C, then 1ml rennet to 7l milk seems to get a set time of an hour and a half.  If hotter, still like 33C which was the temperature on the occasion I first got the hour and a half set  by adding too little rennet by mistake, 1ml rennet to 10l milk.  So I adjust how much rennet to use roughly based around that scale.

I think that this suits me better because I’m not the sort of person who can cook to a recipe every day.  I like to get the gist of a technique and then cook it my way. Certainly looking ahead to when I’m doing my own thing, this is something I’d be interested in continuing.  At the beginning of the season, of course, I couldn’t apply this attitude to cooking, to cheesemaking.  I needed to stick to the recipe religiously because I didn’t have the experience and also because I’m making cheese for someone else.  It wasn’t my sales on the line if I messed it up.  I suppose with a bit of experience and practice I’ve got more confidence now to react more to the circumstances of the milk temperature on the day rather than make it do what I want and heat it to a specific temperature every day.

It seems to be a more forgiving recipe that we’re using now with the longer set.  There’s more moisture but it’s not free moisture.  The curd is more fragile and needs more gentle cloth pulling but still seems to drain appropriately anyway.  Even moister cheeses still don’t have the levels of free moisture.  The first cheeses made with this sort of set, are maturing rather nicely.  I like the texture of the one cheese I’ve kept back in the stores (and that I’ve marked for me to buy for myself  when it’s ready).

The other thing is that we’re leaving the starter for about an hour to mix and get working in the liquid milk before adding the rennet.  The idea behind this is that the bacteria can get going better because it should be easier for them to get distributed and to get dividing in a liquid rather than in the set curd.  Or so we hypothesise anyway.  Another thing that should help this also is the fact that at temperatures like 27C, the milk reaches its first fragile set much more slowly.  In fact it can still be liquid an hour after the rennet has been added but still reaches the firm set (or second set as it can be known) in about an hour and a half or a little longer.

My gut feeling is that this long set and longer ripening time will make a good texture and flavour when the cheeses are mature and ready to sell.  Time will tell I suppose, but if the mistake cheeses of the 28th June are anything to go by, I can allow myself to be cautiously optimistic.

Home made Starter

A couple of years ago, Martin tried out making St James cheese using acidified Swallet whey as a starter and also souring his own milk.  It gave interesting but inconsistent results and his EHO got worried so he stopped and returned to his old DVIs.  He didn’t forget the idea however and with the use of pint starters this year, it’s something that we’ve talked more and more about.The argument for using your own starters is to achieve as complex a starter as you can.  The most basic starters are the DVIs which are designed to acidify efficiently and exist in a freeze dried powder that’s easy to look after and simple to apply.  However in terms of containing complex cocktails of bacteria, that’s not what they do.  Pint starters like the MT36 that we use at the moment are a more complex bunch of bacteria with more of an emphasis on flavour production than ease of use.  Souring your own milk will have a greater cocktail of bacteria because it is everything that’s naturally present in the milk itself.  The advantage of diversity of bacteria is that each bacterium will break down proteins using slightly different enzymes which affects the way the proteins are broken down and the combinations of single amino acids they are broken down into.  This in turn of course affects the flavours that are produced.The flavours we want in cheesemaking are primarily a result of the breakdown of proteins rather than fats.  Initially the protein will be broken down to peptides and at this stage the flavours are very basic – salt, sweet, bitter etc.  The enzymes continue breaking the protein down smaller and smaller.   From peptides, they get penta peptides and finally amino acids themselves.  At each stage the flavours develop in complexity and become more aromatic and savoury.  So a complex bunch of bacteria and by extension a complex bunch of enzymes should mean richer, more savoury and complex flavoured cheese.

So we took 100ml of milk, warmed it up in water heated to about 30C and then left it at the room temperature of the dairy which is about 26C for 2 days.  By this time it had thickened into a smooth yoghurt-like consistency.  From this 100ml, we added 10ml to a litre of milk we had pasteurised in a bain marie, stirred and poured it into 8 sterilised pots leaving some left over in a jug.  After 20 minutes for the bacteria to grow accustomed to their new medium but without giving them enough time to start reproducing, the pots were frozen.  The left over mixture in the jug was covered and left overnight to acidify which it duly did – and it tasted great too.  I ate some of it for lunch.  We then sent 1 of the frozen pots off for testing for pathogens and total viable count.  From this we can tell if there are any nasty bacteria present and if so if they are present in quantities that will mean they get the competitive advantage when added to our fresh milk at the start of cheesemaking.  The test results were, we thought, satisfactory and emboldened by that, we gave it a go and used it for just 1 batch of cheese on Saturday 16th July.

Having called in a bit of advice from the clever clogs that are Hodgson and Cordle, we were prepared for the cheese to acidify at a different rate and indeed it did just that.  A much slower acidification happened despite the starter itself having quite a high acidity at the time we used it.  This has meant quite a different cheese which probably at the moment isn’t reaching the potential you might’ve hoped for.  However we have tested it too just to double check the test results on the starter and again they are satisfactory.  We’re doing another test with a different lab just to make sure before selling it, but signs are actually pretty good to do a few more experiments using larger quantities of starter to get the acidity developing at the same rate as our MT36 starter does.

Most importantly, how do they taste?  Well they seem to have a firmer centre than our other cheeses with the normal acidity profile and I’m not entirely sure they’ll break down completely but the flavours so far are good.  There’s a creamy breakdown under the rind and certainly the flavours of the curdy centre aren’t too acidic and are quite mellow and rich.  It’s too soon to say for definite that this will be the way forward but equally it’s encouraging enough to try it out again and see what happens.

Milk – the most underrated food in the world

So many people have either decided they don’t really like milk as a drink or just don’t think about it other than to put a bit in their tea or coffee.  When you taste the sort of milk you buy at the corner shop or in the supermarket frankly that’s not a surprise.  What comes out of those cartons is watery, vaguely mineral in flavour if you can really detect a flavour and when it goes sour, it’s chemical, aggressive and unpleasant.When I worked at Neal’s Yard Dairy, we used to hold regular tastings of the milk from our supplier Geoff Bowles at Ivy House Farm.  While this milk was and indeed still is pasteurised, it’s Jersey milk, organically farmed and has a whole heap more flavour than your standard supermarket pint.  Jersey milk has higher fat and protein levels than regular milk which more than likely comes from a rather intensively farmed Holstein herd and is therefore what people in the dairy world refer to as white water.  As I mentioned in the post about cows, Holsteins are very efficient producers of large amounts of milk but it’s not milk that’s particularly rich in fats and proteins and let’s face it, that’s where the flavour is.  Jersey milk therefore has a much richer and creamier mouthfeel but even in the skimmed milk because it has more protein too, it has much more flavour.  We tasted the milks side by side and the Ivy House Jersey milk was naturally sweet, creamy, savoury and mineral.  The supermarket (probably Costcutter actually cause that was the nearest corner shop / mini supermarket) milk was thinner textured and had none of the sweetness or savoury flavours more of a mineral that verged on the metallic.  In part this will be down to the breed of animal but also the freshness.  We knew that our milk delivered to us on one day would have come from the milking the day before.  With the supermarket milk who knows how old it was by the time we bought it.  It would have been collected from various farms, pasteurised all together with lots of other milk and bottled, sent to a distribution centre and from then out to the shops.  It was more likely to be a few days old at least.Since moving away from London and getting access to really fresh milk (minutes old in fact) that is unpasteurised into the bargain I can safely say that the difference between what I’m making cheese with and what you put in your coffee is like night and day.  In fact it’s hardly fair to even call them by the same name.  Of couse I’m working with sheeps milk which is different to cows milk in consistency, it can have rich and creamy fat content but because of the way the fats are structured, it doesn’t feel heavy and the savouriness has a different flavour because it’s sheepy in a subtle and fresh way rather than say beefy.  Those are tricky adjectives because truthfully that is what I find it to taste like but equally I can see those who are unconvinced by milk not warming to the idea of a rich sheepy or beefy thirstquencher.  Anyway, pressing on regardless, I shall continue.  My main point is that if you ever try unpasteurised truly fresh milk it is a revelation.  It has sweetness, fresh, clean creaminess, savoury animal flavours and and mineral restraint but as well as that, it has another aspect in that it tastes lively, which is perhaps a reflection of the freshness.  Supermarket milk with its age and pasteurisation is flat even at worst case perhaps slightly stale tasting.  Geoff Bowles’s milk had sweetness, creaminess and rich savouriness but damn fine stuff though it was and is, by comparison to milk that’s unpasteurised and just milked a few minutes ago, it had lost an edge.

Of all the foods that have lost their character by industrialising the manufacturing process, which include bread, beer, hydroponically grown veg, flavourless battery-farmed chicken and plenty of others too, I now feel that milk is the one that has suffered most in the loss of flavour and perception.  The fact is, most people who reckon they don’t like it, would happily drink a glass of the milk Nicola and Martin produce because it’s bloody delicious.

Milk being piped into the vat from the milking parlour – minutes old.

Temperatures

As the sheeps milk decreases and due to a phone conversation Martin had with Randolph, we have been looking at temperatures of our make recently.  Out at Randolph’s country residence Old Kate’s Farm, Dr Jemima Cordle has been conducting cheesemaking experiments.  According to Martin, she’s been making cheese to roughly a St James recipe but playing with different temperatures and amounts of rennet to see what gets the best results in terms of producing heavier cheeses and a greater yield of cheese.  Obviously as we have less milk, that’s quite an attractive idea to us too.Perhaps a little ambitiously we thought we’d try dropping the temperatures slightly before we had a truly accurate way of recording the temperature.  The floating thermometer we have been using is about 9 degrees out.  The recipe for St James calls for setting the milk at 31C and by the thermometer we had been using, we were setting it at 23C.  You’d think that knowing this, we could drop to setting at what the thermometer tells us is 22C and try experimenting.  However, as it turns out, the thermometer is inconsistently inaccurate – great.  The first 2 days experiments have had to be discounted due to too much yeast in the starter which lead to gassy cheeses.  Dropping the temperature just a little slowed down the drainage and allowed them to take advantage of the extra moisture and get going far more than we wanted.  Experiment abandoned we invested in a good digital thermometer and realised that our previous 23C was in fact about 33C by the new equipment standards.

The temptation at this point would be to return to 31C set straight away, but by setting at 33C we had actually been getting a set time of about an hour and sometimes longer (which is not too short a time for this recipe) and more importantly the cheese has been good.  The NYD mongers have been reporting good things and the cheeses on Martin’s counter at Cartmel have also been tasting good.  So while that’s hotter than we’d intended, if it ain’t broke don’t try and fix it all at once.  We agreed to drop to 32C set temperature for starters and gradually reduce it from there on.

The temperature and set time that Jemima had found to yield most cheese is 28C and a set of an hour and a half which is longer than we have yet achieved.  By setting at what is probably 33C (it was with the old thermometer) and using half the usual quantities of rennet by mistake (1ml to every 10 litres rather than to every 5 litres) I did manage to get a set of an hour and a half.  The curd did set and it was a nice consistency at both cutting and ladling but the texture of the cheese is quite different to the usual St James.  It’s moist and succulent but sandy in texture.  In fact it reminds me of young Stichelton which considering that that is a cheese made with very small quantities of rennet is perhaps not entirely surprising.  However until it matures, we can’t be sure if dropping the rennet quite that drastically is a good thing or not.  Sometimes by making mistakes, you stumble on something good.  Sometimes, you don’t.

However armed with new thermometer in hand, I have been dropping the temperature a little by degrees.  For a few days I was renneting at between 32 & 33C (we can measure in decimal points now) and in the past couple of days I’ve dropped it further to between 31 and 32C.  Martin remains nervous about gassy cheeses, but by adapting the draining cloth work, I think we’re avoiding them.  In fact even the yeasty cheeses we made about  a fortnight ago haven’t remained gassy although they haven’t drained as I’d like either.  But they’ll be ok – not amazing but ok and for a while we weren’t sure that would be the case.  As far as set time goes, the magic hour and a half has eluded me so far but the set is a little over an hour – generally about an hour and a quarter.

The effect of dropping the temperature on the draining was the biggest difference I noticed.  It’s manageable but the curd drains less freely.  This really should be expected.  As I understand it, the reason for this slower and longer set is that rather than forming a number of stronger bonds as the curd solidifies, it forms perhaps weaker bonds but more of them and this at the end of the day forms a more effective net in which to trap moisture and fats so that the curd releases less whey when it is cut and left to rest and it needs more encouragement to continue draining after ladling.  The texture at cutting and ladling is less firm and it actually feels really nice to work with – more like gliding a knife through it than making the effort to cut.  After the curd is in its moulds however this means that it’s delicate and you can’t pull the cloths up as tightly as quickly.  So the cloths are pulled up and tucked in gently after ladling is finished.  The second cloth pull is 20 minutes later and whereas since then we’d been waiting for an hour to do it again, I now find that it needs looking at anywhere from half an hour to 40 minutes later instead.  At this point the curd is getting firmer and can stand a tighter cloth pull in which I aim to have pulled the curd in from the side of the mould so that it doesn’t touch the sides of the mould all the way round.  I won’t neccessarily have it pulled in so that it stands alone all the way round but certainly on some sides or corners it will.  The final cloth pull is then an hour after this and again can be pulled up quite firmly with the aim of standing alone from the sides of the mould as much as possible.  I usually have some cleaning or cheese turning to do after that and I’ve been keeping in mind the idea of a 4th cloth pull but so far by the time I get to cloth pull 3 I feel it’s probably drained enough.  The following morning, in general, the cheeses feel firm and well drained, perhaps a little softer than those made at the higher temperatures but no squelching that indicates free moisture.

In terms of yield and weight and whether we are getting more cheese as a result, my gut feeling is that we are.  Certainly in the last couple of days when I dropped down to between 31 & 32C, I seem to be getting more cheese than I’d expect.  I am not sure about what they weigh, but they seem to be perfectly reasonable sized cheeses and as they are well drained, it’s not trapped whey making them that size.  What I have noticed is that where I’d expect to get 11 cheeses by a process of calculation alone, I get 12 and where I thought I would get 10, I got 11.  In part this can be explained by the composition of the milk – it has higher solids in the latter half of the season than at the beginning but my gut feeling is that it is helped by the temperature and length of set too.

Certainly at this stage of the season when we’re very nearly down to 1 vat of milk only, every little extra is going to help.  The downside is that the longer set and lower temperatures can favour things like yeasts if the drainage doesn’t work so getting those cloths attended to turns out to be pretty vital.

Resting curd just before ladling.  This is the stage at which less moisture releases naturally at the lower temperatures and so more attention is needed to the cloth stages later.