Fermented foods, part 1

Some time back, here or on some other blog, I talked about how easy it is to make yogurt.
See here, and here.
I've got my system down pretty well now. I still have my 1qt Salton yogurt maker.

Ingredients:

• a little less than 1 qt milk, skim, low fat, whole, or supplemented with half and half, depending on taste
• 1/2 to 1 cup of dry milk powder
• 1/8 tsp stevia powder (optional, or substitute your preferred non-sugar sweetener)
• 1-2 tbs plain yogurt

Procedure:

1. In a glass or stainless steel container mix together milk, dry milk powder, stevia
2. Place container in a water bath maintained at a slightly less than a simmer, with a digital probe thermometer in the milk
3. Maintain milk at 180 deg F for 30 min, or 190 deg F for 10 minutes. Don't let it get to 200 deg F.
4. Remove from water bath, and cool back down to under 115 deg F. 
5. Mix in yogurt.
6. Place mixture in container in yogurt maker (following manufacturer's instructions) for 4-12 hours, depending on how you like it.

Some notes on this:

• I add the dry milk powder because it makes for a thicker, more custardy yogurt
• Step 3 I learned from Harold McGee in On Food and Cooking. The heating denatures the whey proteins, which also makes for a thicker, more custardy yogurt. It's only really necessary to heat the milk to about 160 deg F to kill off any critters that might compete with the yogurt cultures.
• For my water bath, I use a slow cooker. It takes a long time, but I don't have to pay close attention to the process, the way I would with a water bath on the stove. I short-cut the process some by boiling the water before I stick it in the slow cooker, and heating up the milk mixture in the microwave. If I wasn't going for denaturing the whey proteins, the microwaving would be sufficient, and I wouldn't need the water bath.

When it works out right, the yogurt has the thickness of greek yogurt, and a texture similar to flan.