Virtually every culture has fermented food in its cuisine.  From the fermented walrus of the Inuit to cider gum sap beverages of the Australian Aborigines, fermentation is as ubiquitous as containers.  Sooner or later, someone leaves a clay pot, animal skin, or basket filled with food.  Sometimes, the resulting substance is not only still edible, but delicious.  As with other culturing techniques, mentioned on Radical Gastronomy, the idea is to provide the right environment for the microbes you want, so that they can overpopulate and create conditions inhospitable for pathogens and spoilage bacteria.  Having coevolved with these fermentation microbes, we can assume that human health is linked to a symbiosis with them. 

Current research supports this connection.  "Probiotics" have been found to fight allergies and eczema, particularly in children of mothers who eat fermented foods.  Digestion is improved with regular additions of beneficial gut flora.  Immune response is improved and lymphocyte production is boosted from consuming fermented dairy products.  Probiotics maintain vaginal health and prevent yeast infections.  The digestive tracts of slim people have much higher concentrations of probiotic microbes than those of the obese, suggesting that one factor in excessive weight gain maybe a diet that is too sterile.  Given that your gut has as many neurons as your dog's brain, it might also be inferred that healthy gut flora are linked to mood, mental clarity, and overall acuity. 

In keeping with the reductionist, centralized, commodification of modern "culture", probiotic supplements abound, on the market.  Because our strawberries are irradiated and sprayed with fungicides, our milk is pasteurized, and our meat is bathed in bleach and ammonia, there is nothing alive in most peoples menu.  The whole mission of the industrial food chain is to achieve high stability and shelf appeal, at the cost of flavor and nutrition.  The question remains, if yeast, mold, and bacteria won't even eat your food, why would you?  To combat this lack of beneficial microbiology in and on our food, we are offered pills.  Why not return to processes that work with nature, rather than sterilize everything and try to cheat our way back to some artificial semblance of health? 

Most fermentations are pretty simple, really.  Stomp grapes and put them in a vat; the yeast living on the skins will eat the sugars in the juice and make wine.  Slice cabbage and crush it with salt; lactobacillus will turn it into sour kraut.  The same is true of yogurt, in a way.  If you leave raw milk in a warm environment, it will solidify into what is known as "clabber".  On the farm, we call this "shed yogurt".  The recipe goes as follows: 

In the morning, feed the cows one bale of hay.  While they eat it (and Maxine has a chance to poop, before being milked) skim the cream from the previous days milk.  Pour the skim milk into a pre-cultured (read: unwashed) bucket, along with any cheese whey, buttermilk, and Greek yogurt strainings, and set it in the meat cave (a shed with two freezers running in it) for 24 hours.  If the day is warm enough, you'll get shed yogurt.  The pigs will push each other out of the way to get at it! 

If you have never experienced clabber, you might mistakenly think it would smell like "sour milk".  Nay.  Sour milk is what you get when you pasteurize milk, killing everything in it, and destroying all of its enzymes, then leave it in the fridge for too long.  Clabber is sharper than the yogurt you may be used to, but nothing like that jug of vomit you find behind the sterile pickles and crusty ketchup bottle, in the back of the typical American refrigerator.  In bygone days, particularly in the South, it was served with garnishes ranging from nutmeg and molasses to black pepper and cream.  The acidity of clabber also makes a suitable leavening agent, should you find yourself lacking baking powder. 

When I make yogurt in the house, it's a bit more controlled.  After attempting to achieve a smooth texture and mild flavor with raw milk, I have found that the naturally occurring enzymes and protein structures prevent a desired result.  Milk cultured straight from the cow, then incubated, yields a grainy yogurt that is prone to separation.  If you want a smooth result, the milk should be slowly heated to 160F, then rapidly cooled to 110F, prior to inoculation.  There may be other cultures that can produce the desired results from raw milk, but more research is required.  As with other milk culturing preservation methods, cleanliness is paramount, to avoid off flavors.  With yogurt, it is particularly important, as it is a progressive culture.  A sample from the old batch is used to infect the new batch.  Instances of contamination compound, over time, rendering your culture potentially corrupt.  This can cause your flavor to become too sharp, or your set to be chunky, grainy, or unstable.  If you use sterile jars and tools, and do not sneeze in it, your culture can be reused almost indefinitely.

Your starter culture can come from a friend, a cheese making supply house, or from any "live active" yogurt you like.  I used the Noosa Greek, in this case.  If you want to order more specialized cultures, you can find a wide range of products.  My process uses thermophilic bacteria, meaning it must be incubated.  Mesophilic options exist that work at room temperature.  There is no need to buy another appliance to make yogurt.  A cooler with a jar of hot water works, as does just wrapping your incubating yogurt in a thick towel.  I use my oven, as described bellow.

"Fruit on the bottom" Yogurt:

Ingredients:

1/2 gallon whole milk (I like raw Jersey milk at cow degrees F)

2 cups jam, of your choosing (chokecherry peach, here)

1/2 cup active yogurt

Directions:

In a heavy bottomed, non reactive pot, heat the milk on low to 160F.  Stir occasionally.  Divide your jam between 8 sterile half pint mason jars.  Leave pint jar empty for your starter for the next batch.  When the milk reaches 160F, move it to a sink of cold water.  Stir as it cools to 110F.  This happens quickly, so stay with it.  Turn your oven on.  If you have a temperature read out, turn it off at 115F.  If not, just run it for a minute to take the chill off.  Arrange your jars on a cookie sheet.  Place your 1/2 cup yogurt in a bowl, or pitcher (my preference, due to imminent pouring). Pour a splash of the warm milk in with the yogurt and stir until smooth.  Add the remaining milk and gently stir for one minute.  Fill all nine jars, secure lids, and slide into the oven, and turn on the oven light.  The heat from the light, and the insulation of the oven will maintain enough heat to incubate your yogurt.  Alternately, Instant pots work great for incubating yogurt. Theres a link to one on amazon, below. Leave it in there for five hours, undisturbed.  Don't open the door and jiggle the jars.  Have faith in your micro livestock to do the job.  Once incubated, chill the yogurt for at least two hours before digging in!

I have used this lovely product in trade for everything from firewood and patio furniture to raspberry canes.  It is so smooth and mild.  The flavor is superior to the store bought version, and the ingredient list is super short.  If you want plain yogurt, skip the jam.  If you want Greek yogurt, chill your finished plain yogurt and line a colander with butter muslin, a tee shirt, or a tea towel.  Set the colander in a large bowl with something in the bottom to elevate the colander. Pour the yogurt into the colander and a allow some of the whey to drain off, for 4-12 hours until desired thickness is achieved.  Use whey for ricotta, baking, chicken feed, or shed yogurt.

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