I know several people have not been successful making it from previously frozen milk (m)
Not sure why, but it never seems to thicken. Of course, if the cultures grow and all else goes well, the yogurt is still just as nutritious and beneficial, despite being "soupy."
Let me see if I can find the link on making BM yogurt. . .I know I've posted it before. Drat, can't locate it in my bookmarks file.
I can give you a brief step-by-step, but if you want really thorough directions, hunt down the book "Super Baby Food" by Ruth Yaron. She has a whole chapter on making homemade yogurt (not specifically from breastmilk, but it works with cow's milk, soy milk, breastmilk. . .the only milk I have had no success with is rice milk). Check your library, or you can order it on her website:
http://www.superbabyfood.com
1. Heat 1 quart of milk to 180-185 degrees (use a candy thermometer) to kill bacteria. You can do this by putting it in a pan, or inside a glass jar set inside a pan, with water surrounding it. Heat slowly & stir often to prevent scorching. Don't boil. Of course, you can do the same with smaller quantities--just reduce the amt. of starter proportionately. The temperatures and times stay the same.
2. Cool the milk to about 110-115 degrees. Add yogurt starter, either powdered commercial yogurt starter (which is what I used--a little more reliable), or 2 Tablespoons of very fresh plain yogurt that contains live, active cultures. Next time you can just use 2 T. of this batch of yogurt as starter, unless you go a long time between batches.
3. Let the yogurt incubate. Basically, this means keep it at 105-112F for 4-12 hours, depending on how tart & thick you want it (it gets tarter and thicker, the longer it incubates.) This is much easier than it sounds--you can put it in a pre-warmed thermos, put it in a jar inside a picnic cooler of water at about 115 degrees (the method I used), wrapped in a towel in a warm oven, in a heating pad wrapped in towels, etc. Any method to keep it warm, and not move it much, will work. In my little picnic cooler, the water would stay warm enough for 6-8 hours if I didn't open the lid. I started with it at almost 120 degrees, and it was generally not down to 105 when it was done.
4. Refrigerate the finished yogurt.
5. Add any flavorings you like: fruit puree, vanilla, chocolate syrup, etc.
I had good success with both soy milk and fresh (unfrozen) breastmilk, when I was making it for my dairy-allergic DS. Rice milk never worked for some reason: it separated into a thin white layer on the top, and the rest was just like clear water. I wrote Rice Dream for ideas, and they said it might be because it was lactose free. They suggested adding a little sugar for the cultures to feed on, but I had the same results and gave up. That stuff is expensive, and throwing two quarts of it down the drain was frustrating1 I also made it with cows milk for myself, and it was DELICIOUS! Much different flavor from most commercial yogurts.
Let me know if you have any questions!
Booker
