Tempeh (also written as Tempe) is a soybean cake originally from Java in Indonesia. It is made by a natural culturing and controlled fermentation process (by soaking and cooking soybeans and inoculated with the Rhizopus Oligosporus fungus) and incubated for approximately 24 hours that binds soybeans into a cake form.
Tempeh is rich in vitamins from the B group, vitamin A, nicotinic acid, folic acid, pantothenic acid, biotin, and fibers and minerals such as calcium and iron, phosphorus, magnesium, potassium, zinc and manganese. Tempeh is also low in fat and completely cholesterol-free.
By the enzymatic action during the fermentation process, the nutrients are better digestible, components such as oligo and polysaccharides (raffinose and stachyose) and phytines are degraded. The result is a product with a digestibility coefficient of 86%, which is rich in high-quality protein with all essential amino acids. 
Tempeh has a neutral taste, but because it absorbs other flavors well, it is suitable as an ingredient for different dishes. It is widely used in Indonesian cuisine and can serve well as a part of vegetarian or vegan dishes.
Research has shown that tempeh is a remedy for diarrhea; it makes pathogenic micro-organisms, it is difficult to attach to the intestinal wall. 
References: http://www.tempeh.info/nl/  http://en.wikipedia.org/wiki/Tempeh  http://www.telegraaf.nl  http://www.wageningenur.nl  http://www.whfoods.com