Adventures in Cheesmaking

This all started out as a curiosity. Like most stuff we eat there is a rich history behind it. Centuries of experimentation. Cheese is just another example.

From the horse back tribes of the Asian Steppes to the Silk Road camel caravans to Romans Legions to European Monks to today, milk was a great source of nutrition but spoiled quickly and was heavy to transport.

The answer was cheese.

Sunday, July 24, 2011

Labneh, Greek Styled or Strained Yogurt

Like many good end results, this started out as a mistake. We made a batch of yogurt but could not get back and left it culture for over 6 hours. The result, thick creamy curds, a good tart taste and whey separating.

Yogurt Curds placed in cheescloth
The answer - pour it into a colander lined with cheesecloth, wrap it into a bundle and let it drain for about an hour.

 The result - wonderful creamy Labneh or Greek Styled Yogurt. These thick strained yogurts have been a staple of  the Mediterranean, Middle East and South Asia. Its great in cooking or raw and chilled.

We made this with non fat skimmed milk with 1/2 cup skimmed milk powder per liter of milk. The resultant yogurt is thick and creamy with a solid tart tang.
After a night in the fridge some
 clear whey is still present  -
no problem, just leave it
mix it in or poor it off

For a treat, added some fresh local Tupelo Honey

Saturday, July 23, 2011

Quick Cottage Cheese - quick yes, cottage cheese no, tasty - perhaps

There are plenty of recipes out there for "Quick" vinegar based cottage cheese. So I tried it out.

1/2 gallon of skimmed milk
Heat to 120F
Add a bit less than 1/2 cup white vinegar with lots of stirring slowly over 2 minutes
Let stand for 30 minutes
Drain through cheesecloth
Rinse under cold waster
Press to dry
Crumble and salt  and mix in some cream

Well - as you add the vinegar you get a great big glob of curd. I saw a lot of unreacted milky whey so added 5 drops of rennet. After 30 minutes drained and rinsed.

What you get is a chewy, mozzarella like crumble. I added some whole milk to make a cream crumble and then some fruit. It was OK but the texture was not what I wanted.

Next time I think I will try a rennet based method and see it I can get a softer texture.


How it Works

There are lots of different "yogurts" but they all have some similar beginnings. The characteristic taste, texture and smell of yogurt comes from two bacteria; Lactobacillus bulgaricus (a rod shaped bacteria) and Streptococcus thermophilus ( a round shaped bacteria). 

These guys work well together

  • Rod/cocci blends grow together in a relationship referred to as 'mutualism' where the overall growth rate and acid production is faster than either culture on its own. The rods produce amino acids and peptides which stimulate the growth of cocci, and the cocci produce formic acid which is required by rods.
  • The balance between the rods and cocci can be controlled by temperature and pH
    • The cocci prefer higher temperatures (optimum about 46C) than the rods (optimum about 39C).
    • The rods are more acid tolerant than the cocci, so, normally the cocci develop the initial acidity and out grow the rods. But, as the acidity increases the rods begin to grow faster than the cocci.
As an added bonus the L. bulgaricus produces acetaldehyde File:Acetaldehyde-2D-flat.png this is the chemical that gives yogurt its familiar taste and smell.

The low pH gives yogurt it's tangy bite and also the low pH starts to denature the Casein proteins and makes the yogurt nice and thick.

A note on ProBiotics" Lactobacillus acidophilus - Acidophilus bacteria are one of the homofermentative species that like the other bacteria in this receipe ferment milk sugar Lactose to lactic acid and grow well at pH <5.0 and temperatures of 37 C. The commercial starter I used contained L. acidophilus. A range of lactic acid bacteria are naturally occuring in human systems and are considered to contribute to a wide range of positive health impacts. 

The Recipe

1./ Heat milk (I used Kroger skimmed milk) to 180 F for a few minutes. The idea here is to  kills all the bacteria that might be present in the milk and eliminate unwanted competition.


2./ Cover and let cool to 112F and add the starter. In this case the starter I am using is a freeze dried commercial starter but if you save about a cup your yogurt and use that as the starter. The bacteria will wake up once they hit the hot sugary milk and do their stuff. If you want thicker yogurt add up to 1/2 cup of dry milk powder per quart of milk.   What you are doing is increasing the milk solids - so it ends up thicker. 

3./ Let stand for 2-4  hours at this temperature. I used a Yogotherm unit. This is just an insulated box. The longer you leave it the thicker it gets because you are making it more acidic - but the tangier it gets - you choose.

Thick and creamy and tangy after 4 hours

4./ Refrigerate - this stops the bacteria from being active (it doesn't necessarily mill them, so they are ready to be used as the starter for the next batch).

5./ Eat just as it is or blend in some fruit or honey.


Some background on milk and cheese - how does it all work

It's easy to follow the directions on the recipe, but what's going on? The science of food is where the magic happens. There are many great references (one of my favorites if you want to get to the fundamentals of what is going on is  Food Science from Guelph University), on the complex nature and reactions of milk and dairy products but here are some key points:
Start with the milk. Using cow's milk as an example. It a blend of 3.3% proteins, 4.6% sugars and 3.9% fat in water with various minerals - so about 12% - 13% solids.
Of special interest for the moment is that the sugars are mostly Lactose and the Protein mostly Casein.

The short story is this. Various bacteria will eat Lactose sugar and produce Lactic Acid. The Lactic Acid reduces the pH of the milk and once it starts getting acidic the Casein denatures - think of denaturing as a ball of string unwinding. When it does this you get a gell - called "curds" and it separates from the "whey" (as in Little Miss Muffet). Now you have two parts. The "whey" has most of the water, the remaining Lactose and the Lactic Acid and some proteins that require even lower pH before they unwind, and the "curds", a solid mass of nutritious fat and protein and some water, sugars and acid.

The art of making cheese, yogurt and a whole world of other products is how this process is manipulated and fine tuned. How quickly this all happens, how completely, how much sugar is left and how much acid, how it is aged.... Just like wine, cheese is a natural product and once we start the ball rolling with bacteria they will eat what they can until you stop them or they run out of stuff to eat or die. Each will produce specific byproducts that will have taste and smell and texture.

The art is in how this is managed - one path leads to Yogurt the other to Camembert....but it all started with milk.

Like most things - the biology and the chemistry of these every day events are a wonder.

Monday, July 4, 2011

Ricotta July 4th

Took the whey from the one gallon full cream milk mozzarella.

Heated it to nearly boiling with slow heat and stirring.

Was expecting a floating curd but what you get is a fine floc.
Added a glug if white vinegar but in future I don't think this will be necessary.

Let it cool a bit then filtered it through a coffee filter which was very slow but worked

Yield was low about 3 tablespoons but quality look and tasted good. Squeezed filter in cheese cloth.


Next time use fine cheese cloth  and allow to cool - perhaps add a bit more milk to increase yields.

Keep whey and use to store the mozzarella.

Mozzarella July 4th

Microwave Method

1 gallon of Kroger Full cream milk
1 1/2 tsp citric acid in 1/4 cup water
20 drops calcium chloride in a water - liquid from Dairy Connection

mixed and heated to 90F

30 drops of double strength veg rennet in 1/4 cup water -  liquid from Dairy Connection

lid on for 5 minutes

Had a clean break but curds were pretty soft

Left for 2 minutes then cut the curd

Heated with stirring to 105-110 - probably 5 minutes

Removed curds and drained in colander.

Microwaved for 30 seconds - drained

Microwaved for 30 seconds - drained

Placed curd in hot salted water

Kneaded and stretched a bit and made some balls

Took half and re microwaved for 30 seconds - it was at this stage that it was easy to stretch and form - next time I should let it get hotter. It was as hot as I could handle and was "melty" the cheese was shinny at this stage.

Formed into balls and placed in cold salty water. The cheese pretty quickly became soft on the outside so took it out of the water and wrapped it cling.

Creamy taste, good texture but soft and a bit slimy on the outside.
Yield 18 ozs from 1 gallon


To do differently next time:

Salt the curds after they are first removed from the whey
Microwave till 150 F and till it has a sheen and able to be stretched