Tempeh

Tempeh, or tempe in Javanese, is a traditional food made by natural culturing and controlled fermentation of soybeans by two strains of Rhizopus molds: Rhizopus oryzae or Rhizopus oligosporus, that cover the beans with their mycelia to form a cake. It is a staple source of protein in Java made from whole soybeans. The retention of the whole bean and the fermentation process give tempeh a higher content of protein, dietary fiber, and vitamins, plus firmer texture and stronger flavor compared to tofu. Its rich nutritional value makes tempeh used worldwide in vegetarian cuisines, partly as meat analogue, while long before it was referred to as “Javanese meat.”

Tempeh is made by soaking, de-hulling, and partly cooking the whole soybeans, and then lowering the pH, usually with vinegar, to create favorable environment, and mixing with fermentation starter containing the spores of the Rhizopus fungus. This mix is then allowed to ferment for 18 to 36 hours at a temperature around 30°C (86°F).

To produce good quality tempeh you need a starter with millions of the Rhizopus spores and contain no contaminating, coliform or pathogenic bacteria. It is often extended with sterile rice flour or starch to standardize the spore count. In Indonesia tempeh starter is either a piece of the previous batch tempeh, or dried starter made by incubating a handful of cooked and inoculated soybeans between two hibiscus leaves for a few days until black spores covering the soybeans and then drying them in the sun. To use the spores, the hibiscus leaves are then rubbed above the soybeans to be inoculated. These types of starters are vulnerable to other molds or bacteria contaminations, but the climatic conditions in Indonesia are so ideal for tempeh fermentation that the contamination is not troublesome. In Western countries pure cultures are used to insure consistent quality and to minimize failed batches.

Tempeh keeps well frozen for several months and refrigerated for about 10 days. As with other fermented products, a little mold on the surface of tempeh is harmless.

Since whole soybeans are used, tempeh is fiber-rich. It is also a generous source of calcium, B-vitamins and iron. Fermentation makes the protein in tempeh more digestible, and the Rhizopus culture greatly reduces the oligosaccharides associated with gas and indigestion. In traditional tempeh making, the starter culture often contains beneficial bacteria that produce B12 vitamin.

Tempeh has a smoky, nutty, meaty, and mushroom-like flavor. In Indonesia it is usually consumed with rice or as a snack. Its tender, chunky and chewy consistency makes it an excellent addition to a variety of foods. Tempeh on the grill is delicious; frozen can be well grated to replace ground beef, as in tacos; fresh is suitable for marinades and deep fried; and dried provides an excellent stew base for backpackers. Tempeh can also be used in chili, stir fry, soups, salads, spaghetti sauces, sandwiches, and casseroles. Vegetarians use it as a substitution for breakfast meats, such as sausage and bacon.

Fermented Soybean Products

Some soy foods are made by fermenting soybeans. In the process soybeans are inoculated with some microbes, mostly done with a starter, to push the process in the desired direction. These fermented soybean products contains higher amounts of calcium and vitamin K2.

There are many fermented soybean products in the Asian, especially East Asian cuisines; miso, tempeh and natto are among the many.

Miso

Miso is a traditional Japanese seasoning produced by fermenting, most typically, soybeans, with salt and the fungus kōjikin, resulting a thick paste used for sauces, spreads, and pickling vegetables or meats. A Japanese soup called Misoshiru use this high in protein, vitamins and minerals fermented soybean product as a mix.

Miso is a source of Lactobacillus acidophilus. This fermented soybean product also contains lecithin, a kind of phospholipid that is effective in the prevention of high blood pressure. Some experts suggest that miso can help treat radiation sickness. However miso contains salt, which is essential to animal life in small amount but may cause a variety of health problems in excess.

Tempeh

Tempeh, or tempe in Javanese, is made by fermenting soybeans with Rhizopus molds strains, Rhizopus oryzae or Rhizopus oligosporus that binds the soybeans into a cake form. This fermented whole soybean product is chunky, tender and is consumed daily in Indonesia as part of the main meal, or as a snack.

Tempeh's fermentation process and its retention of the whole bean give it a high content of protein, which is more digestible, dietary fiber, and vitamins. The Rhizopus culture also greatly reduces oligosaccharides that are associated with gas and indigestion. In traditional tempeh making, the starter culture often contains beneficial bacteria that produce vitamins such as B12. Tempeh is also a generous source of minerals such as calcium and iron. Its nutritional value makes this fermented soybean product used worldwide in vegetarian cuisine, partly as meat analogue; while traditionally it is referred to as “Javanese meat.”

Nattō

Nattō is a traditional Japanese food made from soybeans fermented with Bacillus subtilis. A popular breakfast food, protein-rich nattō, together with miso, formed a vital source of nutrition in feudal Japan. There are also other traditional Bacillus subtilis fermented soybean food products in many other Asian countries.

Nattō contains large amounts of Vitamin K, and a much larger amount of polyamine than any other food. Vitamin K involves in the formation of calcium-binding groups in proteins, assisting the formation of bone and preventing osteoporosis, while polyamine suppresses excessive immune reactions. According to a study, fermented soybean products also contain a very important Vitamin for the skin, PQQ.

Some substances in nattō is said to be good for reducing blood clotting and avoiding thrombosis, as in heart attacks, pulmonary embolism, or strokes. This fermented soybean product may also prevent amyloid-type diseases such as Alzheimer.