The health benefits of these remarkable, delicious healthy foods are outstanding. Tofu is valued chiefly for its high protein, which ranks from a low of 4 percent on a wet basis (in the silk style) to a high of 15 percent (in the extra firm or dense style).
Tofu has one of the lowest ratios of calories to protein food in any known plant food. One gram of useable protein is accompanied by only twelve calories. Tofu is 95 percent digestible. It is an excellent weaning or geriatric food. Its Net Protein Utilisation (or NPU, an index of how much of a protein can actually be assimilated by the body, as compared to eggs, the standard 95) is 65. This is exactly the same as chicken and only slightly lower than beef at 67. 250 gms of tofu supplies up to 25 per cent of the adult RDA for protein, 20 percent of the iron, and 20 percent of the phosphorus.
Fresh tempeh has even more protein than tofu, with 19.5 percent, or about as much as beef and chicken (in quantity), and 50 percent more than a hamburger. Tempeh has the highest quality protein (measured in PER) of any soy food, 2.43, compared to milk at 2.81; a wheat-soy tempeh has a PER of 2.79. Because tempeh is fermented, it is easy to digest, rated at 86 percent, and has a NPU of 56 (plain soybean) and 76 (for wheat-soy).
One strong attraction tempeh has for vegetarians is its high level of the essential vitamin B12, commonly thought unavailable in the vegetable world. 250gms of tempeh may contain as much as 160 percent the adult RDA for B12. Tempeh contains only 157 calories per 100 grams, making it excellent for dieters.
As with tofu, the protein content of miso varies with the style and recipe, ranging from as high as 20 percent to an average of 13. Miso contains vitamin B12 and is rich in enzymes and lactic acid bacteria (as in yogurt). As a concentrated protein source, miso's NPU is 72, so that, 100 grams supplies more useable protein than an equal weight of a hamburger. Miso, which is usually 12 percent salt, reduces salt intake while adding flavour to the diet. Like tofu, miso has one of the lowest ratios of calories to protein, with as little as 11 calories per gram of protein.
Soy foods clearly have the nutritional profile to become the daily protein backbone of the meatless or conventional diet. Foods such as tofu, tempeh, and miso, consumed in normal quantities along with grains, vegetables, and other foods, can supply excellent and sustainable nutrition.