Tempeh

Tempeh (/ˈtɛm.peɪ/), or tempe (Indonesian), is a traditional soy product originally from Indonesia. It is made by a natural culturing and controlled fermentation process that binds soybeans into a cake form, similar to a very firm vegetarian burger patty. Tempeh is unique among major traditional soy foods in that it is the only one that did not originate in the Sinosphere.
It originated in today's Indonesia, and is especially popular on the island of Java, where it is a staple source of protein. Like tofu, tempeh is made from soybeans, but tempeh is a whole soybean product with different nutritional characteristics and textural qualities.^[1] Tempeh's fermentation process and its retention of the whole bean give it a higher content of protein, dietary fiber, and vitamins. It has a firm texture and an earthy flavour which becomes more pronounced as the tempeh ages.^[2][3] Because of its nutritional value, tempeh is used worldwide in vegetarian cuisine; some consider it to be a meat analogue.

History

Tempeh being sold in Java, early 

 

20th century

Tempeh originated in today's Indonesia, probably on the island of Java. The earliest known reference to tempeh appeared in 1815 in the Serat Centhini [The Book of Centini]. ^[4] Three detailed, fully documented histories of tempeh, worldwide, have been written, all by Shurtleff and Aoyagi (1985, 1989, and 2001).

Production

Sliced tempeh

 

Tempeh begins with whole soybeans, which are softened by soaking and dehulled, then partly cooked. Specialty tempehs may be made from other types of beans, wheat, or may include a mixture of beans and whole grains.
A mild acidulent, usually vinegar, may be added in order to lower the pH and create a selective environment that favors the growth of the tempeh mold over competitors. A fermentation starter containing the spores of fungus Rhizopus oligosporus is mixed in. The beans are spread into a thin layer and are allowed to ferment for 24 to 36 hours at a temperature around 30 °C (86 °F). In good tempeh, the beans are knitted together by a mat of white mycelia.
Under conditions of lower temperature, or higher ventilation, gray or black patches of spores may form on the surface—this is not harmful, and should not affect the flavor or quality of the tempeh.^{[citation needed]} This sporulation is normal on fully mature tempeh. A mild ammonia smell may accompany good tempeh as it ferments, but it should not be overpowering. In Indonesia, ripe tempeh (two or more days old) is considered a delicacy.

Nutrition

The soy carbohydrates in tempeh become more digestible as a result of the fermentation process. In particular, the oligosaccharides that are associated with gas and indigestion are greatly reduced by the Rhizopus culture. In traditional tempeh making shops, the starter culture often contains beneficial bacteria that produce vitamins such as B12^[5][6] (though it is uncertain whether this B12 is always present and bio-available).^[7] In western countries, it is more common to use a pure culture containing only Rhizopus oligosporus which makes very little B12 and could be missing Klebsiella pneumoniae which has been shown to produce significant levels of B12 analogs in tempeh when present. Whether these analogs are true, bio-available B12, hasn't been thoroughly studied yet.^[8] The fermentation process also reduces the phythic acid in soy [needs citation], which in turn allow the body to absorb all the minerals that soy provides.

Preparation

Fried tempeh for snack. Product of Bandung, West Java, Indonesia

Battered and fried tempeh

Sautéed tempeh with green beans, an Indonesian dish

Tempe mendoan

In the kitchen, tempeh is often prepared by cutting it into pieces, soaking in brine or salty sauce, and then frying. Cooked tempeh can be eaten alone, or used in chili, stir frys, soups, salads, sandwiches, and stews. Tempeh has a complex flavor that has been described as nutty, meaty, and mushroom-like. Tempeh freezes well, and is now commonly available in many western supermarkets as well as in ethnic markets and health food stores. Tempeh performs well in a cheese grater, after which it may be used in the place of ground beef (as in tacos). When thin sliced and deep fried in oil, tempeh obtains a crisp golden crust while maintaining a soft interior—its sponge-like consistency make it suitable for marinating. Dried tempeh (whether cooked or raw) provides an excellent stew base for backpackers.

Types

Name	Description
tempe bacem	tempeh boiled with spices and palm sugar, and then fried for a few minutes to enhance the taste. The result is damp, spicy, sweet and dark-colored tempeh.
tempe bongkrèk	made from or with coconut press cake (see below)
tempe bosok (busuk)	rotten tempeh, used in small amounts as a flavoring
tempe gembus	made from okara
tempe gódhóng	tempeh wrapped in banana leaves
tempe goreng	deep-fried tempeh
tempe mendoan	thinly sliced tempeh, battered and deep fried quickly resulting in limp texture
tempe kedelai	simply tempeh, made from soybeans
tempe kering	raw tempeh cut into little sticks, deep fried then mixed with spices and sugar, often mixed with separately fried peanuts and anchovies (ikan teri), this can be stored up to a month if cooked properly.
tempe murni	tempeh made in plastic wrap without any additives such as grated raw papaya (lit. pure soybean cake)
tempe oncom	also onchom; made from peanut press cake; orange color; Neurospora sitophila

A new form of tempeh based on barley and oats instead of soya was developed by scientists at the Swedish Department of Food Science in 2008. It can be produced in climatic regions where it is not possible to grow soya beans.^[9]

Tempe bongkrèk

Tempe bongkrèk is a variety of tempeh from Central Java, notably Banyumas regency, that is prepared with coconut. This type of tempeh occasionally gets contaminated with the bacterium Burkholderia gladioli, and the unwanted organism produces toxins (Bongkrek acid and toxoflavin) from the coconut, besides killing off the Rhizopus fungus due to the antibiotic activity of bongkrek acid.
Fatalities from contaminated tempe bongkrèk were once common in the area where it was produced.^{[citation needed]} Thus, the sale of tempeh bongkrèk is prohibited by law nowadays; clandestine manufacture continues, however, due to the popular flavor. The problem of contamination is not encountered with bean or grain tempeh, which have a different composition of fatty acids that is not favorable for the growth of B. gladioli but encourages growth of Rhizopus instead. When bean or grain tempeh has the proper color, texture and smell, it is a very strong indication that the product is safe. Tempe bongkrèk which is yellow is always highly toxic due to toxoflavin, but tempe bongkrèk with a normal coloration may still contain lethal amounts of bongkrek acid.

Tempe mendoan

A variation of tempeh cooking method, often found in Purwokerto. The origin of the word mendoan is from Banyumas regional dialect, which means "to cook instantly in very hot oil", that results in semi-raw cooking^{[clarification needed]} and soft texture. The tempeh is dipped into spiced flour dressing before frying it in hot oil for a short time. Tempe Mendoan may seem like half-cooked soft fried tempeh, unlike common crisp fully deep fried tempeh.