I made soyghurt recently, with some inspiration from this forum. I take no responsibility for the safety of this, it is about growing bacteria, so on your own risk, I am no expert, just a happy experimenter. One can split the first steps and just buy soymilk if one wants to.
Approximately(if you don't want approximately 5 litres of soyghurt you can split the recepie):
-1 litre of dry soybeens
-lots of water
-some kind of culture, I used 3 Proviva juice superfruit, but one or two would most probably have been enough, it is a juice with extra much bacteria added, it is Lactobacillus plantarum, it seemed appropriate as beens are plants
(oh, just now reading a little on wikipeadia, which has this to say about it and soy: "In a 2008 study by Juana Frias et al., L. plantarum
was applied to reduce the allergenicity of soy flour
. The result showed that, compared to other microbes, L. plantarum
-fermented soy flour showed the highest reduction in IgE immunoreactivity
(96–99%), depending upon the sensitivity of the plasma used.")
-1-3 decilitres of sugar (a lot of it will be eaten by the bacteria, so it will taste less sweet when done than if you tast it just after adding sugar)
-few pinches of salt
-2-3 teaspoons of agar-agar
-(I also put a grounded pill with probiotic bacteria in, but made the mistake to mix it with the agar-agar, which has to be added before boiling, so it died, but this can be an idea too, to add in more kinds of bacteria)
1. Soak the beans in water a little less than 24 hours before boiling (say before you go to bed the day before if doing it in the afternoon), make sure there are no stones or clay, remove beens that look bad.
2. Remove beens that are still dry (don't know why this is, but often several beens are all dry still)
3. Put some in a mixer, perhaps 1/4 beans and the rest water, mix well.
4. Put a sil over a big saucepan, and some thin fabric in it, pour you mixture in it, let it drip and then press out as much milk as you can.
5. repeat 3 and 4 until you are out of beans.
6. Mix the agar-agar and salt with water, pour it in the soymilk, and add the sugar, while stirring.
7. Put on the lamp in your oven if you live in a colder climate, if not, don't bother.
8. Let the soymilk boil up, and boil a little bit while stirring occasionally, it is easy for it to boil over and to get burnt in the bottom, so watch it.
9. Let it cool down to bodytempterature. Meanwhile, prepare jars or plastic containers, for example by putting some water in them, and microwave them until they boil and get desinfected by the water and steam, from now on you have to be very carful about hygene, you don't want to grow some bad bacteria.
10. When the milk has cooled down to body temperature, add the cultured product of your choice and stirr. Pour up in your containers and put in the oven with the lamp on or if you live where it is warm (+30), whereever. Leave it for approximately 24 hours.
11. Because of the agar-agar, it will be more like pudding than youghurt now, so clean a handmixer (or other mixer if you don't have one) well, and mix the soyghurt for a few seconds. (I quite liked the pudding as well and ate some of it like that instead, but it didn't go well with cereal or fruit)
12. Serve! with cereal, apple pieces, bananapieces, crispbreadpieces, nuts, treacle... whatever you like.
(before I made a similar, but didn't use soymilk, but just mixed boiled soybeans whole and used, it tasted a bit more bean-like, but I liked that too, possibly it is healthier?)
(Reading a bit more on wikipeadia: "L. Plantarum expresses
and secretes oxalate decarboxylase
, which breaks down oxalates and prevents renal calcium oxalate stone
does that mean eating it can help you absorb more iron? If I remember right oxelates is one of the things that obstruct absorbtion, and it says it combines with calcium and iron to form crystals or similar that you then pee out.
Googled it: seems oxelate's effect on iron absorbtion is contested, but it might have a positive effect in that it might help prevent kidney stones.)