Soy milk is a white liquid made from water and soy beans.
There are different techniques of making it.
In the Japanese way of making soy milk, uncooked soy beans are soaked in water overnight. In the morning they are drained, then mashed with some boiling water, so that they look like gloopy mashed potatoes. More boiling water is added, and the mash is simmered for at least 10 minutes. This not only helps to break down the beans further; the cooking time also destroys a protein in the bean which would otherwise make soy’s much-vaunted protein unavailable to our digestive systems. An anti-foaming agent is often added to stop it from boiling over. After the cooking, the mixture is then strained.
In the Chinese way of making it, the liquid is strained first, then boiled.
What comes through the strainer is soy milk; the moosh that stays in the strainer is called in Japanese “okara.”
The “okara” can be used in baked goods, for livestock feed, or as compost for the garden or fields.
It’s a Western practice to aim for soy milk that tastes like cow’s milk – though not many people will feel that we’ve succeeded. The Chinese version has more of a vegetable flavour.
The Chinese mostly use soy milk to make bean curd (tofu), though sometimes they will drink it served warmed in small bowls for breakfast. In Northern China, you dip a shao bing into it; in Taiwan, pieces of a steamed sponge yellowish cake called “ma la gao.”
In the West, where soy milk is treated as a non-dairy alternative for milk, including drinking straight up and pouring on cereal, the most delicately flavoured soy beans are used.
Every brand of soy milk will taste very different from all the others. In the search for one you like, old hands say, expect to dump a few down the sink.
Soy milk is sold either in cartons or bottles in the dairy chiller section of supermarkets, or in shelf-stable tetra-paks.
Soy milk will not curdle when boiled, but a skin will form on the surface.