Some tips on making yogurt
A friend asked for my tips on making yogurt. It’s easy but has its quirks.
You will need a gallon of whole milk, a cup of “starter” yogurt (ideally also whole), and a 6-quart instant pot. It’s probably most convenient to start this around dinner time:
- Put 3/4 gallon of cold whole milk in your instant pot. Save the rest for your coffee.
- Set the instant pot to saute for ~20 minutes, which should get the cold milk to around 180°F. Try not to let it boil, maybe start with 17 minutes and go from there. Check with a thermometer starting around 15 mins.
- When it hits 180 or so, put your oven mitts on and take the hot pot out of the instant. Put it on your stove, or a trivet, or somewhere it can cool easily for a few hours. If you don’t remove the pot, it will continue to heat up for a while (and likely boil), and also take forever to cool.
- When it’s cooled to between 110° and 100° (it takes a long time!) put the pot back in the instant.
- Add 2 or 3 tablespoons (no more!) of plain yogurt (from the store, or from the last time you made yogurt) and stir gently.
- You can avoid some lumps by mixing some warm milk with the 2 tbsp of yogurt in a separate bowl before adding it all back in.
- Set the instant pot on yogurt mode for 10 hours. Stir it a bit again when you go to bed.
- Go to bed. Sleep well. Dream of cows.
- In the morning your instant pot will beep and you will have yogurt. Put it into whatever container(s) you want and refrigerate.
There are many variables of course:
- Some people say you will kill all the enzymatic goodness by heating the milk to 180, but I think that’s silly. I mean you’re the biochemical engineer here, do your own research. But if you don’t hit ~180°, your yogurt will have a rough, pebbly texture (ask me how I know.)
- Other people say to rapidly cool the heated milk to 100°, I think they’re just anxious. Chill with the chilling.
- Regarding the amount of “starter” yogurt: You’d think “hey, a little extra oomph can’t hurt, right?” but you’d be wrong. Bad texture, for reasons I don’t fully understand but have experienced multiple times. Now I’m careful to not over-inoculate.
- Your “lots of smaller bottles” idea is fun, I just think it will be challenging to find a way to keep the temps and mixes consistent. Since you can decant into whatever containers you want, I don’t really see much advantage. But if you want to have it set up (become firm) in its final shape, yeah, you’ll need a way to handle temps beyond the IP. Some kind of water bath, maybe?
- Like everything microbiological, times and temps are everything.
Good luck fermenting!