There’s something pretty satisfying about making food you can easily buy, like bread, butter, jam…yoghurt! This yoghurt recipe is extremely easy and makes for a fun science experiment too. I promise you won’t get sick and after about 10 hours of patient waiting, you’ll be rewarded with thick, creamy natural yoghurt. It will need a bit of time in the fridge though, to firm up and get cold….unless of course, you prefer warm, just-fermented yoghurt.
This recipe is also amusingly ironic in that its star ingredient is – wait for it – yoghurt. But bear with me. Yoghurt is fermented milk, so in order to make it, you need to introduce bacteria into warm milk. It’s possible to buy yoghurt culture which comes in little sachets, but it’s much easier to use existing yoghurt, with live cultures inside, in order to make more yoghurt. I just used my favourite store-bought natural yoghurt and checked the label to make sure it contained live cultures. Theoretically, this could be the last time you ever buy store-bought yoghurt. If you save some of the yoghurt you made, you can simply use it as the culture to ferment your next batch of yoghurt, and forever after.
Ingredients (makes a lot of yoghurt)
about 3 pints (1.5L) of whole milk
6 or 7 heaped tbs of your favourite plain natural yoghurt with live cultures
1. Take the store-bought yoghurt out of the fridge and allow it to come to room temperature. While waiting, put the milk into a pot and bring it to boil over medium heat.
2. Stir the milk frequently while it heats – this ensures it doesn’t burn. Once it bubbles a little, take it off the heat and allow it to cool down. Boiling the milk ensures there’s absolutely no bacteria in your milk and helps to make your yoghurt thicker.
3. Once the milk has cooled down but is still pleasantly warm (like a bath), add the yoghurt and give it a gentle stir. As the milk cools, it may have formed milk skin. Just scoop it off and discard.
4. Get a big clean container – I used a large pickling jar. Flush it with boiling water in order to sterilise it and warm it up. Pour in the milk and yoghurt mixture and seal the container (or put a lid on it).
5. Put the container in a warm place to allow the bacteria from the yoghurt to multiple and ferment the milk. Places might include a warm oven, next to a heater or radiator, or even wrapped up in a blanket with a hot water bottle. You’ll need to keep the container pleasantly warm for at least 10 hours. Don’t constantly move or shake the container, as you want the yoghurt to set.
6. After 10 hours or so, check the container. The milk should have fermented and you’ll have yoghurt! Pour the warm yoghurt into a container (I used tupperware boxes). There will probably be both yoghurt and watery whey. Either drain or spoon the whey and discard it (if you desire a thick yoghurt) or simply mix it back into the yoghurt. Give the yoghurt a gentle whisk with a fork – this makes it smooth and breaks up any lumps. Refrigerate until cold. Done! Your yoghurt will keep in the fridge for a good week.