29 January, 2015

Cheap and easy way to make yogurt -- in a rice cooker

I've been making my own yogurt for years and have developed my technique with easy DIY in mind.Home made yogurt is so much cheaper than store bought stuff as all you need is milk and a little starter (left over from a previous batch).
EQUIPMENT:
  • Cooking thermometer: make sure you use one with a long stem and easy to read (very large) numbers.
  • Rice cooker with a glass lid: if you don't have one of these, get a second hand one from an Op shop...and learn to cook your rice on the stovetop using the steaming method.
  • Insulated bag.
COMBO
Make sure the steam hole in the rice cooker lid is of a wide enough diameter to allow the insertion of the thermometer stem. (Or that your thermometer arm is narrow enough to pass through the cooker lid eyelet).
My cooker takes 3 litres of milk...and makes 3 litres of yogurt. It lasts us a week. I used to make larger quantities but fresh yogurt will start to 'go off' after 10-14 days. Best to treat it like milk with a limited shelf life.
METHOD
  • Fill the rice cooker with full cream milk, insert the thermometer through the eyelet hole in the lid and turn on the machine. 
  • Heat milk to 82 degrees Celsius (180F)
There is no need to stir. Just keep checking back to monitor the temperature as it rises.
  • Turn off rice cooker as soon as the milk warms to  82 degrees, remove milk filled bowl, with lid still on and thermometer inserted, and place in an airy spot to cool.
  • Allow warmed milk to cool to 43/44 Celsius (110/111F)
  • When cooled, spoon in 2 tablespoons of store bought Greek yogurt  or yogurt from an earlier batch.No need to stir it in. Just plop.
Chris' Yogurt is good ...so too is Dairy Farmers Greek Yogurt. "Pot set" yogurts are all good. So long as you like the taste. What you want is a reliable culture that's still very much alive. You can also add any probiotic strain you may have if you want -- such as from a probiotic supplement (just screw open the capsule).But remember, once you've done one batch, it can be used to inoculate the next. Over time the bug mix will be specific to your kitchen just as sour dough strains are.
  • Replace the lid, then place the cooled and inoculated milk in an insulted bag.
I use 'Hot Bags' I got from South Africa...but if you wrap up your rice cooker bowl in a beach towel and placed it in an insulated shopping bag you'll get the same effect.
  • Leave the yogurt to ferment overnight or for 12 hours at least. 
  • Refrigerate your yogurt in the container you made it in: the rice cooker bowl. 
You can decant your yogurt but it can be a messy and wasteful business. It also fosters contamination.The Easiyo insulated yogurt maker containers you can get in the supermarkets are too tall for easy fridge storage...and the lids aren't secure. A rice cooker bowel fits in my refrigerator OK. I recommend that you store as you cook.
  • As you come towards the end of each batch, set aside (in a clean glass jar) a couple of tablespoons to inoculate the next.Don't rely on bottom scrapings.
Bon appetit!

The mistakes you can make with yogurt making are straightforward:

  • Burning the milk. Some caking on the bottom is OK but don't lift that layer up so that it mixes with the milk above.With the rice cooker method, burning has not been an issue.
  • Not keeping to the temperature parameters. Don't add the inoculant above or below the recommended temperature. You'll still get yogurt but much less of it as the ferment will be very milky.
  • Ferment times. I ferment for  about 12 hours (overnight). The longer you ferment the tarty-er the yogurt flavour