The Pleasures of Yogurt-Making
Update 23 March 2012: This post has been renounced by the author and superseded by a more recent update about why we should avoid all animal products, including milk and yogurt.
Before being incinerated by the eruption of Mt. Vesuvius in 79 AD, the polymathic Pliny the Elder occupied himself by writing the world’s (or the West’s, anyway) first encyclopedia in the form of the 37-book Naturalis Historia. In Book XI, Chapter 96 of this work, Pliny provides us with the first written description of a substance that would later (after the 11th century) come to be called by the Turkish word “yogurt”. This ambrosial dairy product is one of my most indispensable daily indulgences, either mixed with cereal, used in fruit salad, or occasionally as something more exotic like a tzatziki sauce antipasto. It is healthy as well as delicious, being a source of protein, calcium, and all the B-vitamins (which are especially sought-after by vegetarians). The live cultures present in yogurt are also a boon for digestion as well as the immune system. One must be careful to avoid, however, the types of sugary confections and brand-name nonsense that seems to dominate the formidable dairy aisle of typical big-box supermarkets. I am pleased to say that I have lately found an escape from the labyrinth of the worst commercial excesses of a food product that I cannot be without– I make it myself.
For many years (more than I care to remember), I was quietly and increasingly disturbed by the preponderance of little plastic packages that I would accumulate in the course of fulfilling my yogurt habit. Indeed, these sad, misshapen little tubs were among the few remaining vestiges of the world of plastic packaging that I had already sworn off as my irreconcilable foe. In addition, as with all store-bought food products, I had to ask myself what kind of sinister milk-producing industry was really behind my colorful and innocent-looking yogurt servings. Now, I am overjoyed to finally live in a world in which I can take hold of my own yogurt destiny, securing the goods practically from the source, and can contribute in some small way to a healthier and happier planet (and self). Let me tell you how…
I have recently discovered, in the center of town no more than 200 meters from my house, a milk machine. This machine dispenses milk just as easily as an airport water fountain (but without the annoying security checks). For the price of only 1 euro for a liter, or 50 cents for a half liter, I can fill up a glass bottle with fresh milk. But whence does this milk come, you ask? From a local organic milk farm a full 5 kilometers away. Don’t have to worry about extra costs and pollution due to transportation, I dare say. I have visited the farm myself, and can confidently report that there is no sign of an exploitative dairy-industrial complex at work here. The cows are free to wander an (admittedly small) parcel of grassland, and also take in a large part of their diet through omega-3-rich linseed.
I will now provide detailed instructions on the yogurt-making process that follows the procurement from local provenance. N.B.: I understand that most readers may not yet be in the fortunate position of having such a benevolent fresh-dairy source so close at hand. My recommendation would be to do some research, seek out small local organic milk farms in your area to lobby, and, in the meantime, if you must continue to purchase the starter milk at a supermarket, be willing to pay slightly more to find a reliable brand that is as local and healthy as possible. Don’t worry, you will see the financial savings returned to you by way of your soon-to-be sustainable homemade yogurt source.
1.5 liter pot, cooking thermometer, insulated bag, several small glass jars
Empty the milk from the bottle into a pot. I use a dark, 1.5 liter terracotta pot (the traditional Pugliese type; dark color is better for heat retention as well). Put the cooking thermometer in the pot, put the lid on the pot, and begin to heat it at the lowest temperature setting. It is important to slowly heat the milk because this helps to avoid the milk being burned onto the bottom of the pot, and also helps to monitor the rising temperature. You do not want it to boil. You want to heat it to a temperature of around (but not exceeding) 85〫C (~ 185〫F). This temperature kills off unwanted bacteria, and denatures the milk proteins so that they set together rather than form curds. This heating may take around 15 minutes, during which I lightly stir the milk once or twice just to ensure smoother heat distribution. After reaching the desired temperature, turn off the heat.
At this point, you want the milk to cool down to around 43-45〫C (~110〫F). This is the temperature at which the live bacteria cultures will best grow and multiply to form your yogurt. If you want to speed up this cool down, you may put the pot into cold water until it reaches the correct temperature– I never find myself in such a hurry and simply wait for it to cool down naturally (15-20 minutes, perhaps). During the cool down, the fatty cream will form a thin surface on top of the liquid. You can stir this back in to the milk if you like, or you can spoon it out (it will stick quite easily) if you want a lighter, soupier yogurt. The first time you make the yogurt, you will have to buy a small single-serving yogurt at the store to serve as your starter culture. Make sure in this case that it is a high quality, all-natural yogurt with live cultures in it. I used one that was especially high in the healthy probiotics from the live bacteria (which should include, at a minimum, Lactobacillus bulgaricus and Streptococcus thermophilus, and could also include Lactobacillii acidophilus and bifidobacteria for extra zest).
As soon as the milk is at the desired temperature, add to it the pre-purchased yogurt and quickly stir in the contents freely. Then, put the lid on the pot and place it gently into an insulated bag so that it can maintain its heat for over 6 hours. I also like to put it near a heater and cover it with a blanket. It is possible to find a “yogurt-maker” in the store, which should probably be nothing more than a heat incubator for this last portion of the process. It is not necessary, as the pot (especially if you use a terracotta or ceramic like me) will stay hot enough without an expensive gadget. Be careful not to disturb the pot during its incubation, and set your timer for 6-8 hours. I usually remove from the bag at around 7 hours, but it takes some experimentation to find the time that is right for you. If it is too short, the yogurt will not have time to ‘set’ itself properly, and if it is too long it might begin to turn liquidy again.
After removing the pot from the bag, there is usually a yellowish liquid on top, but otherwise you will see a solid white mass of gloriously fresh yogurt. Stir it together vigorously and prepare to scoop it into your preferred glass jars for refrigeration and storage. My first jar is a little one in which I take out a few tablespoons to serve as the next batch of yogurt starter. This way, you do not have to purchase any yogurt after the first time, but can always sustain the process independently. Then, I am able to fill 4 medium glass jars with the remaining yogurt. One liter of milk will provide you with the same amount of yogurt, and is enough to last 2 people up to 4 days (5-6 days for one person, though this is probably the maximum time I would want to store the yogurt). Put the newly-filled jars in the back of the fridge (the coldest part), and enjoy at your leisure the next morning (or after a few hours if you really can’t wait).
You have now created several days supply of fresh healthy yogurt for a fraction of the cost (in money, and to the environment) than if you continued to buy it pre-made. Now, repeat, tell you friends, and have fun with this much-improved system for the rest of your life!