This homemade soy yogurt is made with just 4 ingredients and a simple process, for a delicious and versatile vegan yogurt recipe with no unnecessary additives or added sugars! Lactose-free, nut-free, dairy-free, and yet creamy and delicious!
Before you begin making the soy yogurt, sterilize everything you'll use, as you don’t want the yogurt cultures competing with any bacteria on/in the tools. This includes the pot and bowl for the milk, the glass jar (or small jars) to store the yogurt, and the spatula and/or spoon (wooden or silicone) you will be using.To sterilize the tools, wash them with hot soapy water and then dry them in the oven (no plastic parts) for 10 minutes at 160ºC.
Step 2: Prepare the soy milk.
If you're using homemade soy milk, then you can follow the method outlined here.First, mix the agar-agar and cornstarch with a little milk and whisk until it's a smooth slurry.
Then add the soy milk and slurry into a large pan and heat over low-medium heat* until it reaches 85ºC/185ºF**. Stir occasionally, so the milk doesn’t stick to the pot's bottom. Don't rush this step - it could take 30-40 minutes to warm it up enough.
Once the temperature is reached, remove it from the stovetop and allow it to cool down to 45ºC/113ºF. It's essential to wait until the temperature drops before continuing with the next step (or else you may kill the yogurt starter immediately). This can take a further 30-40 minutes.
Once the milk has cooled, add your yogurt starter, and stir gently until completely mixed in.If using a powder starter, dissolve it with a bit of milk to create a ‘slurry,’ then pour in the pot.
Step 3: Incubate the yogurt
Pour the soy milk yogurt mixture into your containers of choice. I use individual serving small glass yogurt jars.
Place the glass jar/s in a warm environment to “incubate” overnight. I wrapped mine in a warm blanket and left to incubate for 12 hours in the oven (while it's switched off). The longer it ferments, the tangier the yogurt will taste.Chef's note - I'll often make this yogurt in the evening after my dinner, so the oven is often ever so slightly warm still. If you haven't used the oven for a while, you can pre-heat it at 400F/205C for just 2-3 minutes, then switch it off before placing the jars in to incubate.If you want the yogurt very thick and sour, you can incubate it for up to 24 hours. Then move it to the refrigerator.
After the incubation period, I like to refrigerate it for another 6 hours before eating any as it further thickens. Then, flavor or sweeten if preferred and dig in!
How To Store
Store the soy yogurt in the fridge in airtight containers for between 4-5 days.I wouldn’t recommend freezing the yogurt as the cornstarch doesn’t remain thick when frozen and thawed.It is possible to sous vide can these for longer-term storage (4-6 weeks), though it isn't something I've tried.
Notes
Read the blog post for my TOP TIPS on how to successfully make soy yogurt every time!* If you rush the heating process, the yogurt can become grainy or even fail if you heat the milk too quickly or scorch it. This step can take up to 30-40 minutes.** If you don’t have a thermometer, switch off the heat before the milk starts boiling (right about when the simmering small bubbles start changing into bigger ones). You could also dip your pinkie (clean!) in the warm milk, and you should be able to withstand the heat for 7-10 seconds before it starts to hurt. Be careful with this and touch the mixture lightly before plunging your finger into it so you don’t get burnt.
To prepare this soy yogurt in an instant pot, add all of the ingredients to the pot, and heat (allowing it to vent) for between 13-16 hours on the yogurt setting (I can’t be more precise as I haven’t got an Instant pot- so relying on user feedback. It is usually ready by hour 12 and will continue to thicken and become tangier the longer you ferment it.
You could also use a yogurt maker, following the instructions in the manufacturer’s guide.
The fermentation period will affect how thick and tangythe yogurtbecomes. So, you can leave it to incubate for a few hours longer for even thicker, tangier results.
If you want even thicker yogurt, you can strain it through a nut-milk bag - the same way I do with this Greek-style yogurt and then whisk, for super smooth, creamy soy milk yogurt.
If you notice separating, awful smells or any pink spots/mold appearing these are signs that the yogurt fermentation hasn’t gone right and will need to be started over with a new batch.
Don't add any sweetener/flavoring to the yogurt until it has incubated, otherwise, it can affect the fermentation process. I prefer to flavor and sweeten a single jar at a time, just before eating it.