Making soy yogurt

by Lili Mounce

Following making cow's milk yogurt (see here), I tried my hand at soy yogurt. I can't have dairy, and hate to be left out on mornings when breakfast is yogurt, fruit and granola or berries. So here goes my attempt at soy yogurt.

Soy yogurt is dreadfully expensive in the store. Over a dollar for a tiny 6 oz. container! Not wanting to risk all my stock of soy milk, I made just 1 quart of soy yogurt. I followed my instructions for dairy yogurt, with just a few modifications.

I substituted soy milk for the cow's milk, in amounts/proportions to the starter, consistent with making dairy yogurt.  (1 quart (950 mL) of soy milk to 1/4 cup (60 mL) yogurt starter). I cooked this on Medium flame until 190 degrees F (87 C). Cooled in a water bath to 120 degrees F (48 C). Whisked in yogurt starter and poured into jars.

I used the picnic cooler, filled with 120 degree F (48 C) water, for an incubator. I let it incubate for an additional hour and a half (for a total of 4 1/2 hours -- I'd like to try 6 hours next time). All that I'd read about soy yogurt indicated that a longer incubation period is helpful.

To prolong the warm environment in the picnic cooler, after 3 hours I scooped out some of the water with a saucepan, heated it on the stove for a bit then added this heated water back into the cooler. This gave me another hour of warmth for my make-shift incubator. At the end of about 4 hours 30 minutes, I took the yogurt out and put into the fridge. 

soy yogurt is thinner than dairy yogurt, but still very good,
here it is, next day, just before being strained

Soy yogurt is thinner than dairy yogurt. The simplest remedy, I found for that, was to strain the yogurt the next day, through a coffee filter set in a strainer, over a bowl. After 1 hour, about 1/4 of the yogurt had strained out as whey. After 2 hours, about 1/2 of the yogurt had strained out as whey. This gave me a very creamy, very thick soy yogurt that I found very satisfactory. If I'd wanted soy yogurt cheese, I could've left this to strain in the fridge for 24 hours or so. 

soy yogurt after straining for 2 hours

With the whey that is strained off, you can add as liquid in baking. My daughters were baking a cake that same day, and used the whey in place of part of the milk called for in the recipe. The whey can be refrigerated to use in 2-3 days for baking/pancakes. Or, you can freeze it for baking another week. Some people like to add it to their smoothies.

You should be aware that soy milk is darker than cow's milk, and so soy yogurt will turn out darker in color than regular yogurt. This is just an FYI, you haven't done anything wrong if yours isn't as white and creamy as dairy yogurt. From what I've read Soy Dreams brand soy milk will have a "whiter" result.

not quite as white as dairy yogurt, but I don't mind that at all

Use a soy milk beverage that is high in fat, protein and has some sugar added. This is no time to use a bargain soy milk or a fat-free soy milk. Compare nutrition facts on the labels to find the highest fat and protein content soy. You will have a thicker product and the bacteria will have the food they need to do their work. My soy yogurt was sweeter than the dairy stuff I made earlier in the day, due to the added sugar in the soy milk. But I was totally okay with this. It made a pleasant tasting yogurt, without being too sweet, that required no additional sweetening.  I used Trader Joe's Soymilk Extra for this batch.   

I used dairy yogurt as starter. I know my own body and I can handle a small amount of dairy. Though it is an option to use a commercial soy yogurt (with the right live active cultures), for a totally vegan/non-dairy yogurt. I also read up on a method of culturing soy without a yogurt starter at all. Evidently chili peppers have the right bacteria on the stem for culturing soy.

I must admit, the soy yogurt is delicious. I've about eaten all that I made (1 quart), just a couple of days ago.