1Heat 2 quarts of soy milk on medium heat in a saucepan until the temperature of the milk reaches 110˚F. Note: I measure out the milk in the jars before heating it, because a 1/2 gallon box of soy milk usually has a bit more milk in it than what fits in the jars, and I hate wasting anything! If the temperature of milk goes up above 110˚F, let it cool back down to 110˚F before adding starter culture. Once soy milk reaches 110˚F, remove from heat and whisk in the contents of the packet of starter culture. Quickly and carefully dump out the hot water from the jars and fill them with the cultured soy milk. You may want to use a ladle so you don't lose any milk when pouring. Seal jars with the sterilized plastic lids, but not too tightly.
2Incubate jars for anywhere from 8-24 hours until cultured soy milk is thickened to a yogurt consistency. Soy yogurt will look a bit clumpy and watery compared to store-bought yogurt, hence why I strain it to produce labneh. At this point you can refrigerate the yogurt or continue on to make labneh. See below...
1Place a sieve over a bowl and line it with a lightly dampened coffee filter or several layers of cheese cloth (or possibly a nut bag would work too). Note: Chemex style coffee filters are perfect for this because they unfold into a large square.
2Pour 1 quart of the yogurt into the coffee filter and you will immediately see the whey being sieved from the yogurt. I sieve 1 quart at a time but you could set up another sieving apparatus and do them simultaneously if you wish. Fold the edges of the coffee filter or layered cheesecloth over the top of yogurt and return it to the fridge to complete sieving. Pour off whey if it fills bowl enough to touch the sieve. Save whey for other uses if you wish (google it).
3Let it sieve for anywhere from 2-12 hours until desired consistency is reached. Transfer labneh to a bowl, using a rubber spatula to scrape off any labneh that sticks to the coffee filter. Labneh will still look a little clumpy at this point. Whisk labneh until it is smooth if you wish to eliminate clumps. The clumps melt right out in your mouth but may not look as appealing as when whisked smooth.
4Yogurt and labneh should keep refrigerated for up to a month, but we usually eat it within the week it was made. Use your nose if you are unsure. Cultured milk lasts longer than milk.
5That's it! After you make your own soy labneh I doubt you will ever return to those over-processed non-dairy yogurts from the store.
2 glass quart sized wide-mouth mason jars
2 plastic wide-mouth mason jar screw caps
incubator--see details/options outlined below
large coffee filter or cheesecloth
Notes on milk: I use soymilk made with only organic soybeans and filtered water, because I'm trying to get away from all of the thickeners, flavors and other additives found in most non-dairy milks and packaged yogurts. I've tried to culture our own homemade soy milk, and while it came out very thick, the flavor was very strong and very beany. So we reserve the homemade stuff solely for making tofu. WestSoy and EdenSoy both make an unsweetened version with only soybeans and water. I have not tried to culture other non-diary milks like almond, rice or coconut, so I do not know how they will turn out using this method.
Notes on culture: I use Cultures for Health direct set vegan yogurt stater culture. It comes in singles use packets, which will culture up to 2 quarts of milk at a time. I like this company and their cultures have not failed me yet. Unfortunately non-dairy milks do not reculture well, and a new starter culture will need to be used with each new batch of yogurt.
Notes on incubation: Being my frugal self, I have not purchased a yogurt maker, although the Yogotherm looks tempting and does not require electricity. For now I use a seedling heating mat, which we already had and use to hatch seedlings for the garden. First I wrap the jars in a towel and then in a thick blanket. Then I place that whole bundle on the seedling mat and wrap the mat around the whole thing and secure it there with a bungee cord. Sounds more complicated than it actually is. I usually incubate for about 12 hours, but have let it go longer, up to 24 hours, if the yogurt did not look cultured enough. Another method I've heard of but have not tried is to fill a cooler with boiling water and place sealed jars inside to incubate. You can get creative and think of your own ways to incubate in your home. Always place your incubator in the warmest part of your house. If you have a yogurt maker, follow the manufacturer's instructions for incubation.