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When you are going to explore the culinary of Indonesia especially in Java island, of course there is a moment you will find Tempe, a popular and indigenous side dish of Indonesia. Tempe was originally made by ancestor of Indonesia around 20th century when the food technology was not evolved like today. The availibility of soya bean and mold starter culture, then tempe is ready to made through controlled fermentation. We can find so many types of tempe that will be processed in various way. For example tempe gembus that is made from tofu pulp and tempe bongkrek that is made from coconut pulp. Till today, Tempe is not only popular in Java Island but also almost in around of Indonesia even in many countries. As a result, we can find so many stages or version to make tempe from various workman.

Generally tempe was made from stages like boiling the soya bean, soaking, peeling, washing. slicing, cooling, inoculation, packaging with old banana leaves or perforated plastic, and incubation. Microbes that are involved are coming from species of mold like Rhizopus oryzae, Rhizopus oligosporus, Rhizopus chinensis, and Rhizopus arrhizus (Rahayu 2015). From these mold that has been inoculated to ready-soya bean, we expected the fermentation condition will stimulate to release some enzymes like protease and lipase. The enzymes will degrade the complex protein of soya to be more easy to be absorb. Not only that, soya bean fermentation will result much various nutrition and functional compund like GABA (Gamma Amino Butyric Acid), antioxidant enzyme like Superoxide dismutase (SOD), and also isoflavon that has been trusted its benefit to maintain the health. Even if the making process looks easy, but we should apply the ideal stages because it was very risky to produce unwanted tempe. If we use too many mold starter culture so the fermentation process will not perfect, and it would give effect to the sensory taste

Like told before, we can not stop to talk about benefit compounds in tempe that exist from the activity of the microbes. During fermentation, there are chemical and biochemical changes of macro compunds like protein, carbohydrate, and lipids, also micro compounds like vitamins and minerals. Proteins will be hydrolyzed by proteases into peptides and amino acids. This changes generally lead to increase the bioavailibility (Rahayu 2015). But the kind of the microbe was so various. Nuraida (2015) said the reality showed that is not only spesies from Rhizopus that is abundant in tempe. The making process of tempe was not 100% applied a sterile stages since handling of raw material or personal hygiene of the workman. Therefore we can find also the bacteria like Bacillus, Klebsiella, Enterobacteria, and another. Klebsiella pneumoniae take a roll to synthesis of vitamin B12. Another microbe also take a roll to reduce the amount of saponin and phytat, an antinutrition compound in soya bean. BSN (2012) said that the fitase enzyme that is produced by mold will degrade phytat acid (which binds minerals) into phosphorus and inositol. This degrade will make the minerals becoming more available to be use by body. Meanwhile this fermentation process on tempe will increase the degree of unsaturation of fat. Due of this process, there is an increasing number of unsaturated fatty acid in tempe. These unsaturated fatty acids has an impact to decreasing the amount of serum cholesterol which can neutralize the negative impact of sterol in the body.

The perfect fermentation will release a sensory satisfaction and also the compund that contribute to decrease the deseases risk. Isoflavon is still the special compound of tempe. There were many researches that have been published about its efficacy. For instance its potential to decrease the risk of cancer, antiaging, antiatherosclerosis, and antidiabetic. The international diabetic federation 2017 showed that the amount of diabetic sufferers in Indonesia increases every year and totally there are ten millions people who are diabetic. This reality was heartbroken so the research that has been discovered about isoflavon efficacy is expected to open the public insight to be more aware with diabetes through lifestyle improvement (especially in dietary habit).

Diabetes mellitus is one of non communicable desease (NCD) which intimately tangent to modern society. Diabetes is divided to type 1 (DTP1) and type 2 (DTP2). DTP1 occurs when the pancreatic B-cell can not produce insulin as usual that has a role to decrease the blood glucose. Meanwhile DTP2 occurs when the receptor at surface of cell is resistant to receive the signal of insulin. As a result, the blood-glucose keep increase because the cell cannot absorb it. DTP2 is related to unhealthy lifestyle like to many exposed to free radical. Free radical will cause stress oxidative that affect the stability of the insulin receptor that is made from protein. Even if our body has natural antioxidant that is supllied from enzymes or vitamins, but it can not enough to handle the exessive stress oxidative.

Soy bean and their products are rich in isoflavones, a non-nutritional component from class of poliphenols and is a type of flavonoid, which has properties as an antioxidant. Genistein is naturally present in abundant soy isoflavones followed by daidzein which does not have OH group on C5 (when compared with genistein) (Fig. 1). Soy isoflavones conjugated with glucose as glycosides. The main structure of the isoflavone aglikon is composed of two aromatic rings associated with heterocyclic piran ring. When in the large intestine, genistein will go through the metabolic pathway to being dihydrogenistein (DHG) or 6’-hidroxy-O-demestilangolensin (6-OH-O-Dma), while the daidzein will be reduced to being dihydrodeidzein (DHD) and then converted to (O-Dma) or equol (Gilbert et al. 2013). We will talk more about genistein isoflavone below to improve the function of pancreatic B-cells to produce insulin.