Who would’ve thought making yoghurt could be so complicated. Well, maybe not so much complicated as tricky. Half a degree too hot and you’ve messed it up. I tried a few of the techniques suggested by the Internet, including using a slow cooker, but I think keeping a steady temperature of 43 degrees over 8-12 hours is harder than you’d think when you don’t live in a warm country.
Some people just suggested preparing it and then wrapping it in warm towels, but I know if I do that in my house, even with the heating on, the warmest you’d get is to about 15 degrees. Leaving the oven on for 8 hours doesn’t seem like a great idea either, and also my oven’s lowest mark is 60, so even if I could set it to 40ish at a guess, that’d probably be too risky.
Anyway, after wasting more than 5 litres of soya milk and getting nowhere near the yoghurty taste and consistency I was looking for, I ended up deciding to buy a yoghurt maker. It was less than £20 and I am a yoghurt-eating monster so I knew I’d pay it off in less than 4 batches.
These instructions are based on making it on the yoghurt maker, but the process is the same whatever you use to incubate it, so if you make sure it’s between 43 and 45 degrees by the last step, you can use your method of choice to incubate it for 8 to 12 hours. Also, making it with milk is pretty similar, only that you probably won’t need a thickener. You’ll need:
– 1 litre of unsweetened soya milk (it’s ok if it’s got added calcium, and it doesn’t have to be organic or fancy – I’ve sometimes used Asda’s Smart Price one and it worked fine)
– 1 1/2 – 2 tbsp soya yoghurt starter (either from a previous batch or plain soya yoghurt bought in the shop)
– 1 tbsp sugar
– 1 tsp ground arrowroot
– Food thermometer
First, you need to sterilise everything. And I mean everything. I sterilised the little glass bottles that go in the yoghurt maker first, and then went on to scald all the utensils I was going to use, a small cup (to dissolve the thickener), a plate to put the utensils on, and the pan you’re warming it up in.
Then just pour about half of the milk in the pan and put it on the stove. If the soya milk is UHT you don’t need to boil it to sterilise it as it already is, but heating it up will help the sugar, yoghurt starter and arrowroot dissolve and mix in better.
While the milk is in the stove, add a heaped teaspoon of ground arrowroot to a cup of water and mix well until dissolved. Then pour this into the soya milk. Different places I checked suggested different thickeners, but this worked quite well for me. Make sure you dissolve it in water instead of adding it straight to the soya milk though. The first time I had a go, I didn’t do this and ended up with liquid yoghurt and what looked like soya milk slugs at the bottom.
Sugar aids fermentation, so add at least a tablespoon of sugar (I used brown sugar as it was the only one I had in the house, but any type will do) to the warm soya milk. Keep whisking together to make sure it dissolves completely.
Now you’ll need to add the starter. I used plain soya milk yoghurt for this. In some places, I read it needs to be “live” yoghurt, but this one wasn’t and it still worked. Both Tesco’s own and Promavel worked fine. If you’ve made it before, you can save a bit of every batch to use as a starter for the next.
Add about 1 and a half/2 tablespoons of yoghurt to the pan and whisk. When everything is mixed together and dissolved, remove the pan from the hob. It doesn’t need to boil, you just need to make sure there are no lumps.
Add the remaining soya milk and that should hopefully bring the temperature down. You can just pour the whole litre in the pan, but I’ve done this before and it took ages for it to cool down to 43 degrees, so this should help. Check the temperature with the thermometer. If it’s not hot enough, put it back on the hob. Otherwise, wait for it to cool down. When it reaches about 44 degrees, it’s ready to be poured into glass containers and either in the yoghurt maker or whatever else you plan on using.
Then you just have to wait between 8 and 12 hours (I always leave it at least 11 or 12, to be on the safe side) for it to ferment. After that, just take it out, cover the jars, and refrigerate.
My yoghurt maker came with a recipe book in which you add vanilla essence or fruit puree to the milky mixture before fermenting. I’m not sure if this works differently in dairy milk, but when I tried to do this with soya milk the whole thing separated and I ended up with a curdled blob of soya milk floating on some liquid. A similar thing happened when I used sweetened soya milk, so I’d recommend you use unsweetened soya milk and add any flavourings after the yoghurt is ready. The soya milk I used had added calcium and that didn’t seem to affect the fermentation though.