By Tyas Rahmah Kusuma

FoodScience 2014

Fermented foods have always been well known to have positive influence on our health. In Indonesia, there are various types of fermented foods. One of the most popular type of Indonesian fermented food is oncom. This particular food is commonly made from the by-products of tofu production (deproteinated soy or soy meal). However, it can also be made from other by-products such as peanut meal (deproteinated peanuts). Oncom is often consumed as an alternative protein source due to the fact that oncom is relatively cheaper than other traditional protein-rich foods such as tempe and tofu. Oncom is often used in Sundanese (West-Javanese) cuisines. Due to its pungent aroma, oncom is often fried first before it is incorporated into cuisines.

In addition to its relatively high protein content, oncom may positively influence our health in more ways than one. Several studies have been done to evaluate the potential health benefits that oncom might possess. An in vivo study in 2000 was done in order to evaluate the effect of oncom on plasma cholesterol level of rats. The results of the study showed a significantly lower plasma cholesterol of rats subjects. This effect is attributed to the protein, dietary fiber and isoflavone content of oncom.

Genistein is an isoflavone that is contained in soy beans. This compound has been associated with antioxidant activity, anti-cancer activity, and other positive biological effects. In oncom, genistein can be found in abundance. Thus, oncom may have the potential to exhibit those biological effects. This fact was proven by a study done in 2012 where the antioxidant and anti-cancer activity of ethanol extract of oncom was evaluated. This particular extract was found to contain genistein in it. The results of the study showed that – although much less compared to vitamin C – ethanol extract of oncom exhibited antioxidant activity. Furthermore, the said extract also exhibited anti-cancer property by selective cytotoxic activity against MCF-7 cells (breast cancer).

A recent in vitro study has found that oncom water extract exhibits an immunostimulatory effect by promoting the innate immune system. In this study, TNF-α and IL-6 – cytokines produced by the macrophage cells – production was promoted in RAW 264.7 cells (macrophage) that were treated with oncom water extract (unpublished data). Further analysis showed that this promotion of cytokine production was caused by the upregulation of those cytokines gene expressions.

Despite the health benefits mentioned previously, there are still a lot of health-benefitting potentials that oncom might offer. For example, oncom might have a positive influence to our gut health due to its dietary fiber content. Therefore, further researches need to be done in order to explore more potential health benefits.

References
Matsuo, M. (2000). Plasma cholesterol reduction by defatted soy ontjom (fermented with Neurospora intermedia) in rats fed a cholesterol-free diet. Journal of Nutritional Science and Vitaminology, 46(1), 30–33.
Mustarichie, R., Moektiwardoyo, M., Levita, J., Muhtadi, A., Subarnas, A., & Udin, L. Z. (2012). the Research Evidence of Antioxidant and Anti-Cancer Activity of Genistein Content in the Indonesian Traditional Food (Oncom) Ethanol Extract. Int. Res J Pharm. App Sci. International Research Journal of Pharmaceutical and Applied Sciences (IRJPAS) Www.irjpas.com Int. Res J Pharm. App Sci, 2(25), 65–7365.