Tempe is vital for the adequate nutrition of many Javanese, whose diet is rice based and contains little animal food. Rice is high in protein, but these proteins are low in the essential amino acid lysine. Soya beans have plenty of lysine, but even after the beans are cooked much of this protein is physically and chemically locked up and cannot be digested. The mould used in tempe fermentation produces enzymes which break up and ‘pre-digest’ the protein and make it accessible to human digestion. Indeed, as
Nutritionists and cooks must agree that tempe has a lot going for it. It contains about 40 per cent protein—more than any plant or animal food—carbohydrates without starch, unsaturated oil without cholesterol, all eight essential amino acids, Vitamin A and several B-complex vitamins, iron, calcium, zinc, phosphorus and magnesium. It can be frozen at almost any stage in its manufacture or preparation.
Tempe is traditionally made from whole, dry soya beans which are washed, soaked until soft, partially dehulled, and boiled for a short time; this eliminates their pungent ‘beany’ flavour. The beans are then cooled to lukewarm, and inoculated with a starter culture of mould (Rhizopus oryzae or R. oligosporus). A small amount of tempe from a previous batch may serve as a starter, or a concentrated culture (ragi, sometimes grown on hibiscus leaves) may be used. The beans are then divided into portions which are traditionally wrapped in banana leaves (preferable to plastic bags) and left to ferment until they have reached the required stage of ripeness.
The origin of tempe is unclear. It has certainly been made for centuries, possibly even millennia. One theory has it that Chinese traders visiting Java showed the inhabitants how to make soy sauce, whose starter, koji, is prepared from soya beans by a comparable process. It is only in the 20th century that tempe became popular outside Java, though even now it is rarely found except where there has been migration from Java on some scale.
Tempe is now used in an increasing variety of ways by Indonesians. Its firm consistency allows it to be sliced, marinated in water and garlic, and then deep-fried. It may be boiled in a sauce, often made with kecap; or steamed in banana leaves; or chopped small after being cooked and added to meat and vegetable stews or vegetable salads.
Tempe can be used at any of four stages in the fermentation process. Tempe koro is given four to six hours’ less ripening time than normal tempe, giving a stiff underripe cake. Normal tempe (sometimes called tempe murni, pure tempe) ripens from 24 to 48 hours and is the most commonly used and the most versatile. Tempe semangit is two or three days older than this, and tempe busuk (rotten tempe) three to five days. The mould gives the tempe a flavour and texture reminiscent of cheese. Tempe murni resembles camembert, while tempe busuk is like mature stilton, being more crumbly and ammoniac in smell; its enzymes also have a marinating, tenderizing effect on other foods when it is combined in mixed dishes.
Tempe and similar products in Indonesia are also made from other vegetables. velvet beans yield tempe bengkuk, winged beans tempe kecipir, wild tamarind seeds tempe lamtoro, and mung beanstempe kacang hijau. See also oncom, a product similar to tempe made from groundnut presscake.
The Javanese are very competitive about various tempes and their place of origin, but it is the tempe murni produced in the town of Malang in E. Java which is usually the most acclaimed, although the kind in C. Java which still uses banana leaves can sometimes be of comparably high quality.
© the Estate of Alan Davidson 1999, 2006, 2014 © in the Editor’s contribution to the second and third editions, Oxford University Press 2006, 2014.