Introduction: Soy Yogurt in Your Instant Pressure Cooker

About: I make and pursue what I call frugal, and excellent, vegan food. For me, vegan cooking is an ongoing series of experiments, utilizing both chemistry and subjective preferences to achieve the ultimate recipes. …

I'm in love. I'm in love with an appliance, which is potentially inappropriate. But I'm willing to bet that if you're reading this, then you're in love with the same kitchen appliance. You get it. You're in love with your instant pressure cooker. You're making beans from dry, soups, stews, all kinds of grains, even cakes and desserts.

But there's one function you haven't tried. Much like Willy Wonka in his Great Glass Elevator, "...and up until now, (you've) pressed them all except one. This one." The "Yogurt" button. It's as intimidating as the button in the movie with the red ring around it. Mmmm... Better not. Leave that one alone.

Or, perhaps you've tried to make soy yogurt. Perhaps you've followed all the instructions in the manual, simply exchanging the dairy milk for soy milk. You faithfully took the milk up to a boil, and let it cool for the recommended interval, having sterilized the mixture. You added your vegan starter. You set the mixture. You ran excitedly to the pot after 10 or 12 hours, and tasted your mixture. It was bitter. WAY too bitter. Next time, you tried a shorter incubation time. You followed the same, excited decanting procedure. The fermentation was there: the metabolic process that consumes sugar in the absence of oxygen. The product was the delicious tangy acid you were tasting.

But it was runny. Why was it runny? You went to video, pinning, and blog posts for advice. You thickened and emulsified your mixtures with arrow root, flour, and tapioca starch.

Did it all have to be so difficult?

Fear not. Take advantage of all my experimental failures and cut straight to using my method. One caveat: don't adapt it, and follow the easy instructions exactly to the letter. Your little cruelty-free anaerobes will feast on the non-dairy sugars, swim in their deliciously acidic by-products, your mixture WILL thicken, and you will feast on the entire microbiosphere for breakfast, desserts, or dressings. You will succeed.

Ready to win at science?

Step 1: Only Two Ingredients: Buy the Right Ones

You only need two things to make soy yogurt: soy milk, and yogurt culture (or "starter.")


Rule #1: purchase one that is made just for use with soy milk. The culture is your bacterial starter. The bacteria that like to eat soy sugars are different than the ones that like to eat dairy sugars (lactose). So get the variant that will be happiest feasting on beans. Go to your interwebs, and search. Any large online retailer sells vegan or soy milk starter. When you get it in the mail, keep it in the fridge. Use one pack per batch.

Soy milk.

No, not almond milk. No, not coconut milk. No, not oat or hemp or goat. Rule #2:Use soy milk. If you have soy allergies or sensitivities, there may be another kitchen scientist out there who can help you - but this one has only had good results with soy milk.

Now it gets more specific. Rule #3: You must purchase a soy milk that has ONLY soybeans and filtered water as the listed ingredients. This is generally your shelf-stable varieties. You'll find them in smaller cartons on, sorry if it is too obvious, on the shelves in the aisles. Read the label. Don't use any that have sugar or carageenan or absolutely anything else added. Have I tried it with others? Yes I have. Have I gotten a good result? No, I have not.

Now, you are set for success. I know, it feels so good.

Step 2: Add Your Soy Milk to Your Instant Pressure Cooker

Add your shelf stable soy milk to the pot. You'll need two 32-oz. containers, or 64 oz. all together.

Step 3: Add Your Culture

Add one packet of your non-dairy starter culture.

You just made the day of billions of bacteria. Accept the massive deposit of good karma into your life's checking account.

Step 4: Whisk.

This doesn't really need fleshing out, does it? Oh! Use a clean whisk. Don't lick it, or dip it in bleach or something crazy like that, and you're basically going to be okay here.

(It is worthwhile to mention that if you want to add salt, sweetener, vanilla or other flavorings, you should not do any of that yet, either.)

Step 5: Secure Your Lid, and Select Your Setting

You'll simply place the lid on your Instant cooker, and secure it. Then, make sure the valve is in the "Sealed" position. Lastly, push the "Yogurt" button.

(You will notice there this is where the instructions diverge from the manual's more complex version of events. If you're making soy yogurt, don't follow those instructions. Simply push the "Yogurt" button.)

Next, use the buttons with the positive and negative symbols to adjust the timer up and down until you are at 9 hours. I've used 9 or 9:30, and they both work well. If you prefer a very tart yogurt, go for the 9:30. If you go longer than this, the yogurt may become bitter. It may also become runnier in texture again. A shorter time may not give your bacteria sufficient time to eat as much as they want, and therefore create enough delicious, tangy acids. For me, this time interval has been the correct balance to intervene in that chemical reaction.

Here is a video of me going through the lid attachment, and starting the Pot.

Step 5: THICK Vegan Soy Yogurt in Your Instant Pot from Gina Witt on Vimeo.

(Note: if you delay the process of adjusting the time for a moment too long, your instant cooker may begin. If this happens, simply hit cancel, and try again.)

Step 6: Remove From Pot and Add Flavorings (If Desired)

At 9 to 9 and a half hours, your yogurt should be thick. Again, you don't want it to continue to ferment, because the flavor will change. Remove the pot from your cooker, and taste it. Now you can add what you like, or nothing at all.

I prefer my yogurt "bare back," but my daughter likes hers with vanilla beans and sweetener. I like to use a clear sweetener, like cassava, so that it doesn't alter the pure white color. Simply add a little, taste, and adjust as you like.

Refrigeration should slow any further fermentation, and preserve the taste of your yogurt. I use sanitized (put through the dishwasher) large yogurt containers from a commercial brand to store my yogurt in the fridge. If it has been sweetened, and vanilla bean specs are present, this has the added bonus of fooling my daughter into believing it is her favorite brand, at a fraction of the cost. Ha. Kids.

Step 7: Enjoy!

Soy yogurt is great on cooked oats, added to overnight oats, on top of spicy stews as a cooling sauce, or added to dressings or cold salads. You can use it anywhere you can use dairy yogurt, and scientific studies show that it carries a multitude of health benefits.

More importantly, my personal opinion is that it tastes better than the dairy version. (THAT part isn't science... But it's compelling, isn't it?)

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