Goodbaker’s Blog

I’m frustrated with the overly-sweetened soy yogurts I find in my local grocery stores. The extreme amounts of sugar in them cancel out any health benefits, in my humble opinion. So after seeing Martha Stewart make homemade dairy yogurt on TV, I decided to make homemade soy yogurt. It’s surprisingly satisfying.

Tools:
- large clean glass jar, or bowl with lid
- cardboard box
- heating pad (like you use for a backache)
- dinner plate
- instant-read submersible thermometer (like for candy-making)

Ingredients:
- 1 Container of unsweetened soy milk
(I used a 1qt carton of Vitasoy Unsweetened Original)
- 1 6-oz container of sweetened vanilla or plain soy yogurt, as fresh as possible.

optional: 1 capsule of probiotic culture, the kind you take as a dietary supplement

Prep:
First you need to determine the right incubation settings:
- 1 day before your first batch, heat water to 110 degrees and pour into your jar or covered bowl.
- Set the heating pad flat in the bottom of your cardboard box
- Put the dinner plate on top (this provides stability and diffuses the heat of the pad)
- Turn the heating pad to Medium
- Put your hot-water jar or bowl on the dinner plate and close the box.
- Wait 2 hours, then use your thermometer to read the temperature of the water. Hopefully, it will be between 100 and 105 degrees. If it’s too high or low, adjust your heating pad controls, wait 2 more hours and check again.

Once you’ve figured out the right settings, you are ready to…

Begin:
- Turn on the heating pad in your incubator box.
- Your soymilk should be sterile. If you were using dairy milk, you’d have to scald or boil it to kill any pathogens that might crowd out the good yogurt bacteria. But since we are using soy milk straight from a sterile tetra (aeseptic) pack, you can skip that step.
- Heat the soy milk to 110 degrees in microwave or on stove. (110 is not that hot, so be careful not to overshoot the desired temperature! Use your clean thermometer.)
- Pour into your sterile jar or bowl.
- Stir in the yogurt, and optionally, crack open the probiotic capsule and stir the contents of that in too, with a clean spoon. (Discard the capsule shell.)
- Cover, and set in your pre-warmed incubator box.
- Now, leave it alone for 10 to 14 hours. Don’t stir it, don’t take its temperature (you already figured out the right settings with the water test, right?)
- When the time is up, get it into the refrigerator and chill. Sweeten or flavor to taste only when you are ready to serve it, (not before you incubate it).

The final texture will be thickened, but not like pudding. More like potato soup. The really thick kind in grocery stores has been thickened with starches or gelatin. If you want a really thick result, you can stir in some tapioca starch at the beginning, when you are heating the soy milk to 110 degrees.

Notes:
The bacteria live on sugars. In dairy milk, they digest the lactose, which is a form of sugar. Since we are using unsweetened soy milk, we must use a container of sweetened soy yogurt to provide the sugars the bacteria need to live.
Alternatively, you can use sweetened soy milk, and unsweetened soy yogurt or a probiotic capsule as your starter. Your homemade soy yogurt will still be a lot less sweet than the grocery store stuff. For example, this recipe will have only 20% of the sugar in each 6-oz serving that the original starter container had.

Remember that every container and saucepan you use must be scrupulously clean, preferably straight from a dishwasher. If you don’t have a dishwasher, pour boiling water into them before starting. This ensures that the only bacteria to grown in your yogurt are the ones you introduce intentionally! Any spoons or thermometers should also be as clean as possible.

Don’t add any acid ingredients until after it’s done and you’ve chilled it. Because acid will prevent the bacteria from growing. So no citrus flavorings, and no maple syrup or agave or honey, until you are ready to serve.

Instead of a cardboard box, you can also use an insulated cooler, if you have one big enough.

Originally posted 2007-02-07

This entry was posted on Saturday, April 5th, 2008 at 10:21 pm and is filed under recipes. You can follow responses to this entry through the RSS 2.0 feed. You can leave a response or trackback from your site.