April 19th, 2015 by Ed Bruske
This week marked an important occasion for us: We started consuming the milk from our Jersey cow, Emily.
Our first milk project: yogurt. The milk looked a little thin, like skim milk. And sure enough, the yogurt turned out runny as well. What could that be about? Well, as novice dairy farmers, we are learning new stuff all the time. Turns out a milk cow gets to decide whether she “lets down” the creamy part of her milk or save it for her calf. Since we’re sharing Emily with her boy calf, it’s a good bet she’s holding back on us–at least for the time being.
How can a cow possibly do that? I’m sure it has something to do with hormones and an instinct for perpetuating the species. The calf is growing by leaps and bounds, but the milk Emily gives us is thin gruel. In fact, it’s getting better incrementally each day. And she is getting a little bit easier to milk as time passes. We’re still going at it by hand, until we can run an extension cord out to our makeshift milking parlor in the walk-in shelter and train her on our new milking machine. We’re told that Jerseys new to milking like to dance around and that would describe Emily perfectly. Not only are we first-time milkers, we’re trying to milk a moving target.
But, back to the yogurt. We’re not trying to make raw milk yogurt. Some purists insist on heating the milk very little, in order to preserve all those microbes that come out of the cow naturally. For the time being, we’re not taking any chances. We heat the milk to 190 degrees Fahrenheit as part of the yogurt process.
To make my yogurt, I’ve always heated the milk just short of simmering. I think many people don’t understand that making thick yogurt is not about how much inoculant (bacteria culture) you put in it. It’s not about how long you incubate the yogurt. It’s about the heat you apply. Because yogurt thickens when heat forces the protein molecules in the milk to bind together. The longer you can keep the milk at a high heat–say, 190 degrees–the thicker it will be, up to a point. If you want to make really thick yogurt–for instance, Greek-style yogurt–then you have to think about draining out the liquids, even using centrifugal force to drain out the liquids.
What I conclude about Emily’s current state of yogurt is that she is still holding back some of those protein solids that otherwise would be binding together to make the yogurt thick. I guess we just have to be patient and keep milking.
As for my yogurt formula, I’ve spelled it out in this space many times. It’s very simple. I fill a quart jar about three-quarters full with whole milk, then add cream to the top of the shoulder of the jar, leaving room for the inoculant (some of the last batch batch of yogurt). Heat this over very low heat in a heavy sauce pan to 190 or 195 degrees. Remove the pot from the heat and allow the milk to cool to 120 degrees. Whisk in a couple of heaping tablespoons of yogurt from your last batch, containing the live bacteria culture. Warm up your quart jar, fill with the milk/inoculant mix and place in a small, insulated cooler with some other jars filled with hot water.
Allow the milk to incubate in this warm environment for 24 to 48 hours, replenishing the hot water in the other jars if you so desire. Voila! Perfectly thick and delicious yogurt. Just add fresh fruit.