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.

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It’s getting real!

 

We have windows and doors in!
We have windows and doors in!

Lots of bits and pieces have been happening recently.  Building work has slowed down a bit since the heady days when the walls went up.  The thing holding us up is that the concrete laid as foundations for our floor has cracks and although it’s quite likely that these are just cracks caused by the concrete drying, we need to be sure they aren’t a sign of something more serious like subsidence.  So we wait for someone with structural engineering knowledge to assess them and sign them off.

Once that is done we can put in the framework for the first floor and with that in place, we can start to put in the panelling that forms the interior walls.  In other words, we’ll have rooms.

Meanwhile I have been working on paperwork still – the end is in sight finally.  Actually, I hope it is, every time I say that to myself, I remember some other record sheet or schedule that I’ll need and it goes on the job list.  We’ve ordered and paid for our industrial dishwasher, the final payment on the equipment from Avedemil has been made and 4 pallets including vat, racks, wash tubs, multimoulds and stainless steel tables should soon be on their way to us.  The pipework to divert our milk out of the main milkline before it can be cooled or can get into the bulk tank is on order and we’re pushing for it to be in by 11th August.

Why 11th August did you ask?  Well because officially I have a date to move south.  7th August.  And come what may, I will be on the payroll as of the 11th as with Rose on holiday in Greece, I’ll be managing the build and using our warm milk, I’ll be making trial cheeses in the kitchen of my house and then maturing them in a wine fridge.  It will be good to get my hands on some curds again – just have to remember to order a few key bits of gear: starters, a tub to make cheese in, an electric blanket and indeed the wine fridge.

The trial cheesemaking came about on a visit from Jason Hinds, David Lockwood and Bronwen Percival from Neal’s Yard Dairy.  They came for an informal morning chat to look at progress, talk about the quality of cheese they are looking for and its implications for milk quality, sales and advice on our financials.  All three of them felt that as soon as the milk was in place, making some kitchen trials would be well worth the exercise in understanding where the milk quality is at this year (it’s bound to be rather different to February when we last did any testing and again to last summer when I was making trial cheeses at SAF) as well as hopefully having something to taste and start to comment on. We’re going to go down to London for a big cheese tasting with Bronwen at the end of August which will be a useful calibration exercise.  In theory I know what their cheeses are like but it’s a few years now since I’ve been tasting them regularly and I’ll need a refresher to check out our washed rind competition.  For Rose, seeing how Bronwen tastes, assesses flavour and quality and understanding what she is looking for will be invaluable.  It’s her job to look after sales when we’re up and running so a bit of calibration with one of our customers (we hope) can only be a good thing.

So it’s a mixed bag as I’m sure will be familiar to anyone who’s been involved in building work: some progress, some delays and on not too many occasions the odd step backwards.  Overall though we’re getting there and with a confirmed date in the diary for me to start work, it’s getting real.

New things are a-happening!

So it has been over a month since I last wrote but buildings are being built, logos are being designed, websites created and as you know from my visit to Avedemil, equipment is being bought.

So, as we left it, we had steels and the best part of a roof.  After that, the builders had to dig drainage channels which meant that progress wasn’t hugely visible but was made.  Finally however we have concrete on the floors and bits of walls up  – brick at the bottom and wooden frames which are going to support traditional dark wood cladding.

The floor is down.  Concrete baby.
The floor is down. Concrete baby.

 

The view that I will be gazing on from my make room as I make St Bartholomew
The view that I will be gazing on from my make room as I make St Bartholomew

 

As you know I already blogged about visiting Avedemil which was an experience for definite but in a good way. While we wait for our equipment to be delivered, we have also been putting our bursary money to good use by commissioning a website.  It’s just a holding page at the moment but with Harry Darby (NYD’s design guru) on our side, we’re hoping for some great things in the future.  So far we’ve just decided on our house fonts and incorporated them into the holding site and business cards.  Photos are to follow!

In the meantime, I’ve been doing a lot of HACCP.  Which, if you’ve done it before, will explain why it’s been a bit quiet on the blog.  My head hurts.

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Nettlebed Creamery Roof

We got a roof!!!!

Dougal Campbell Bursary

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Last week, the Soil Association announced three winners of its Dougal Campbell Cheese Bursary.  We applied, for Nettlebed Creamery, in early February and to be honest didn’t really expect to get anywhere.  But we did.  In fact we are one of the winners!

Dougal Campbell was a very influential figure in the Specialist Cheese industry who I’m afraid I never met.  I do know people who speak feelingly of how inspirational and generous he was with his knowledge and time.  If it weren’t for him, we wouldn’t have either Lincolnshire Poacher or Hafod on our cheeseboards to name but two.

I do remember his cheese though.  In the mid 90s when I was fresh out of university and learning the ropes at this quirky shop in Covent Garden called Neal’s Yard Dairy, we received a delivery of some of the last Tyn Grug cheeses he had made before he died.  Possibly because it coincided with me learning to set up a display and learning to sell and taste out cheese to customers, I can still l distinctly remember the big, heavy natural-rinded wheels that could be built into a pleasingly eye-catching tower.  I remember the cheese’s golden colour and a fruity flavour that flirted with wildness.  I also remember the sadness at his death  that was felt at Neal’s Yard amongst the more experienced mongers behind the counter who had met him and knew the cheese and its maker considerably better than I did.  It feels very apt to have the influence of this cheesemaker again as I’m embarking on another new learning curve.

In order to apply for the bursary, we had give details of how our farm is managed along organic guidelines and our intentions for the cheese.  I found it pretty interesting, not least learning about what Phil the farm manager does.  With a bit of luck you will too.

Nettlebed Creamery is a new business and we are in the process of building a dairy with the aim of making a washed rind cheese and a blue cheese using the organic milk produced on the Nettlebed Estate at Merrimoles Farm.

Merrimoles Farm has been in the Fleming family since 1901. The farm is a mixture of arable, sheep and dairy. The Dairy has been sited at Bix since 1969; it became organic in 2004.

There are over 130 cattle in the dairy herd. They are cross-bred Holstein Fresians with Swedish Reds and Montbelliards.

Some specific farming practices with a view to sustainability

The herd are fed using as much home grown feed as possible including in addition to grazing: clover silage, whole crop barley, grain and beans (approx. 15% is purchased – parlour cake).  The growth of pasture and feeds are managed using a rotation including clover crops to fix nitrogen and provide fodder.  

The cross breeding of the dairy cows (Holstein-Friesian, Swedish Red & Montbeliards) has been undertaken to maintain hybrid vigour and provide long lasting, healthy, fertile animals.

The farm is in the Organic Entry Level Scheme (OELS) and has established grass margins, maintains hedgerows and trees and has areas of low input grassland to maintain and increase biodiversity.  They alternate grazing with sheep where possible to limit the effect  of internal parasites, reduce the need to worm and therefore avoid wormer resistance worms.  They use 500t of Green Waste Compost annually to maintain soil reserves and avoid using finite mined fertilisers. In addition they have invested in energy saving  electric motors and a heat recovery unit at the dairy (milking) to reduce our energy use.

The Creamery, we are building, is designed taking energy efficiency into account.  We will be using water from our neighbour’s woodchip boiler for all our hot water and for our heating as well. We have plans to use solar panels from the roof of the barn next door (our landlord is finalising these plans currently). After our first year of cheese making we will be creating a wetland system to take all the grey water, sewage and the whey from the facility: a system of swales and ditches to filter the waste into clean water. We then intend to plant fruit trees and willows, rushes and wild orchids to assist with the water filtration and at the same time encourage biodiversity.

The cheeses we intend to make will be made using raw milk and using traditional, liquid yoghurt starter cultures.  Eventually we intend to culture our own starters and ripening agents solely from the raw milk produced by the estate and vegetable matter grown on the estate (a valuable potential source of lactic acid bacteria), eliminating the need for bought in cultures.

The cheeses will be entirely made by hand which suits the production of soft and blue cheeses best.  We will use open vats and the cheese will be made without the use of mechanical stirrers as our soft and blue cheeses require a more gentle handling.  A comprehensive set of maturing rooms has been designed to then ensure the cheeses are kept at the appropriate humidity and temperature at all stages of their ripening.

By building a dairy we intend to provide the farm with a future for its Dairy herd which is no longer subject to the fluctuating prices of the milk market.  The need for an alternative customer to the current purchaser on the farm was highlighted at a point when the milk price and amount of organic premium was cut without very much warning. 

Our dairy will negotiate a fair milk price for the farm that allows them to be profitable and importantly that is guaranteed.  In return for milk being produced to specific standards regarding bacterial levels and fat and protein content our milk price can be increased.  In addition to cheese, we have plans to investigate the possibilty of using more of the farm’s milk to produce a range of yoghurts and frozen yoghurt.  This in turn will allow the farm to maintain and improve on its current sustainable practices and will mean it does not have to dramatically increase herd size in order to turnover more money.  

Re-reading this, although these are the aims we’ve talked about since the beginning it does make me feel a little nervous as our aim of fair milk price and providing a sustainable future for the herd will only work if the cheese is as good as I can make it and therefore we sell plenty of it.

No pressure!!

Paris is always a Good Idea

Paris from my taxi ride after the Salon de Fromage
Paris from my taxi ride after the Salon de Fromage

As Audrey Hepburn apparently said, ‘Paris is always a good idea’.  Even better if it happens to be hosting an agricultural show which according to Patricia Michelson of La Fromagerie and various other cheesemakers, is a must see.

With hopes of learning more about farming and cheesemaking equipment, Rose and I booked the Eurostar and set off.  It took a relatively short metro ride to get to Paris Expo and we were able to buy our entry tickets to the Salon d’Agriculture pretty easily.  We acquired lunch and looked at some cows, picking up leaflets on Montbeliards as we went and perused the map trying to find the Salon de Fromage.

Apparently it’s all been a bit easier to find and get into in other years but this year it took full on detective work to find the cheese bit of the show.  This is partly because it’s for professionals only and perhaps the guards last year just got fed up of turning away members of the public but all the same it was due to a good degree of exploration of the site and some fine ad lib blagging on Rose’s part and translation on my part that we got in.

We had business cards for Rose’s old business and luckily because we’d planned on talking about it on the train we had a plan showing the design of our dairy.  We first profered the business cards.  No good.  We called people we knew who were in there.  They weren’t answering their phones.  Rose got out the plans of the dairy and began talking the security guard through the process in franglais.  At this juncture, he realised we were

a) obstinate

b) legitimate

c) possibly slightly deranged

and sent us chasing after a nice lady in a green jacket who officially lead us past the security and to the desk in the hall where you presented your business cards and were allowed to register as a visitor.  Not entirely sure why it had been so cloak and dagger to get to that point but never mind, we were in.

Inside, we wandered around lots of stands of cheese in its many and varied forms.  We stopped by An Bord Bia’s stand and looked at their cheeses, unfortunately just missing a chance to say hi to the Furnos from Cashel Blue.  We found Guffanti’s stand and tried their Taleggio and different types of Gorgonzola.  They were really good.  We, of course, said hello at the Neal’s Yard Dairy stand and in the course of conversation that networker par exellence that is Jason HInds managed to direct us to a good paper supplier and to a nice cheese affineur called Mark who loved the idea of people going into making cheese and has offered to take us to visit some Reblochon producers in May or June.  We also ran into Jonny Crickmore who had come over on a very early train with Julie Cheney and who were both just leaving but we just had time to chat and compare notes on milk testing and things to look at in the cheese show.

After that as we partook of a nice glass of wine (well when in Paris…) at the show’s wine bar / restaurant we took stock, talked about website, packaging, labelling and other things that had absolutely nothing to do with vats and stainless steel but were very productive nonetheless.  And as we rounded the corner on a final tour of the show we managed to finally track down my sister and the inimitable Jon Thrupp who were chatting away to their Beaufort affineur.  They were mid meeting so there was only really a chance to say a quick hello but it’s always nice to run into friends and family even if it is only brief.

Having successfully found paper, Reblochon hosts and had a chance to chat cheese with Julie and Jonny, we set off for the Gare du Nord so Rose could catch a train home.  I stayed on in Paris for a very quiet night in (it had been a very early start) hence the photo of the Moulin Rouge from my taxi and returned to Blighty the following morning slightly regretting not having more time to do a good visit to the recommended Fromageries and buy up all the washed rind cheese I could.

Paris is great. I could have stayed all week!

Meanwhile at Nettlebed the steel is being repaired (you'll notice it's not the same colour as it was) and we're getting closer to putting up the walls and roof.
Meanwhile at Nettlebed the steel is being repaired (you’ll notice it’s not the same colour as it was) and we’re getting closer to putting up the walls and roof.

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.