Fermented Soy: Tempeh

To be honest, any research I have done about soy has only confused me all the more. There are a wealth of research articles about soy consumption and cancer, many of them conducted on cohorts of women using surveys about the frequency and amount of soy consumption.

One thing that I found particularly interesting in my quest to understand the link, if there is one, between soy and cancer, is the difference between the intake of soy products in the United States and the traditional soy consumption in, for example, Japan. Unlike the processed soy products citizens the United States consume, (protein bars, protein powders, tofu, soy burgers, fake meats, soy milk…) soy was traditionally consumed in much smaller quantities and in a fermented form. Fermentation generally leads to a more digestible product regardless of the substrate or original food. This is because fermentation is actually the organism (usually a fungus like yeast) using the sugars and other compounds in the food to grow and in this process ends up “digesting” and changing the compounds that are present. On the Easy Vegetarian Diet website they list some of the nutritional qualities of tempeh that are not found in unfermented tofu. In addition to more B vitamins, important for the production of certain hormones and maintenance of proper brain function, the fermentation process decreases the phytate content of the soy product thus making the iron and calcium easier for the body to absorb.

Whether or not a soy product has been fermented, it is always advisable to eat the food as a whole. In the case of soy beans that means eating edamame, whole cooked soy beans or Tempeh. These whole soy products not only have the phytonutrients that are helpful in preventing heart disease but also still have fiber. Tempeh actually hails from Indonesia and is one of the Indonesians largest sources of soy consumption along side tofu. It is a cake of soy beans (sometimes mixed with other legumes and grains) held together by a matrix of the fungus growing on it. The fungus most commonly used are Rhisopus Oligosporus and Rhysopus Olyzae.

As with all foods, moderation is the key. Whole soy products can provide calories, phytonutrients, and fiber but should not be consumed in excess. I would recommend no more than one serving per day. To get the most nutrition out of the soy you eat, try

Works Cited

Haron, Hasnah, et al. "Absorption of calcium from milk and tempeh consumed by postmenopausal Malay women using the dual stable isotope technique."International journal of food sciences and nutrition 61.2 (2010): 125-137.

Sandberg, Ann-Sofie. "The effect of food processing on phytate hydrolysis and availability of iron and zinc." Nutritional and toxicological consequences of food processing. Springer US, 1991. 499-508.

“Tempeh: The Perfect Vegetarian Protein.” Easy Vegetarian Diet, Web. 16 Nov. 2015.

http://www.thekitchn.com/how-to-make-tempeh-cooking-lessons-from-the-kitchn-202369