RoseMarie Pierce, B.Sc. Pharm., “The Holistic Pharmacist”
Modern science has begun to reveal the age-old health benefits of fermented soy foods.
The Nutrition Committee of the American Heart Association states that “there is increasing evidence that consumption of soy protein in place of animal protein lowers blood cholesterol levels and may provide other cardiovascular benefits” (http://circ.ahajournals.org/cgi/content/ full/ 102/ 20/2555).
Recent findings of the American Cancer Society reveal that breast cancer kills three times as many American women as Japanese women. In addition, colon and prostate cancer in Japan is significantly lower than in North America.
Given this expanding list of benefits, informed Westerners are eagerly incorporating various forms of soy into their diets, hoping to experience a wide range of health benefits, including: potential anti-cancer properties; menopausal symptom relief: osteoporosis protection: and cardiovascular health.
Thousands of soy-based products can now be found in the North American marketplace as manufacturers take advantage of this new health trend. However, the traditional Asian diet contains mainly fermented, organic, non-GMO soy food, rather than the hyper-processed soy products lining the supermarket shelves of North America. These highly processed soy products can be made from isolated soy proteins, soy protein concentrate, soy flour or texturized vegetable protein and include items such as soy baby formulas, vegetarian meat substitutes, veggie cheese and soy milk.
History of the Soybean
The soybean was cultivated in China prior to 3000 B.C., where it was considered one of the five sacred grains along with barley, wheat, millet and rice. However, it was most likely not used initially as a food. Agricultural literature of the period refers frequently to the soybean and its use in crop rotation. The soybean did not serve as a food until the discovery of fermentation techniques, sometime during the Chou Dynasty (1134-246 B.C.). Thus, the first soy foods were fermented products including tempeh, natto, miso and shoyu (soy or tamari sauce). Natto, a food particular to Japan, is a form of fermented soybean that dates back 1,000 years. The soybeans are cooked and wrapped in a pipe made from straw, then left to ferment. As with most fermented soy food, it is rich in vitamins, minerals especially calcium and potassium, fiber and proteins. Meanwhile, the Chinese were discovering that a puree of cooked soybeans could be precipitated with nigari (magnesium chloride) or calcium sulfate to make bean curd (tofu). The use of fermented and precipitated soy products, such as tofu, soon spread to other parts of the Orient, notably Japan and Indonesia.
The humble soybean (Glycine max) has been a source of human nourishment for centuries, yet only in the past two decades has it made inroads into Western cultures and diets. Have we, in North America, been missing the key factor to delivering soy’s health-giving benefits – fermentation?
What is Fermentation?
A traditional food-preparation technique dating back to ancient times, fermentation has been intentionally used to provide improved shelf life, nutritional enrichment, attractive flavor, enhanced food safety and promotion of health. A diet high in fermented food has been linked to longevity and prolonged good health in cultures such as the Bulgarians and Hunzas.
Food fermentation processes employ a wide range of microbes (yeast, molds and certain friendly bacteria) to achieve the desired chemical change to the food or beverage. Depending on what product is intended, different microbes can be employed, such as mold to make blue cheese, yeast to make beer, bacteria to make yogurt.
In the soybean fermentation process, end results such as miso, tempeh, natto, shogu (soy or tamari sauce), and fermented soy powder are produced by a host of friendly bacteria. The bacteria’s active enzymes break down or predigest the complex sugar molecules and the hard-to-digest proteins, significantly improving digestive and nutritive value. There are specific complex carbohydrates (sugars), which are troublemakers in the digestive system, especially in those people suffering from Crohn’s Disease, Ulcerative Colitis, IBS and Celiac Disease. Fermented soy is considered safe for the Specific Carbohydrate Diet (SCD), a strict grain-free, lactose-free, and sucrose-free dietary regimen intended for those suffering from Crohn’s Disease, Ulcerative Colitis, Celiac Disease, and IBS.
Considered to be one of the best vegetable sources of essential amino acids, the whole soybean contains 38 to 40% proteins. Yet soybeans, unless fermented, are very difficult to digest partly due to the high amount of protein enzyme inhibitors and indigestible sugar structures. Improving the digestibility of soy protein is a major factor in the fermentation process, in rendering the proteins more digestible and easier to assimilate than those in the whole soybean. The isoflavones (phytoestrogens naturally occurring in soy) are converted by the bacteria into their “free” forms for improved absorption and more effective usage within the body. Soy fermentation also yields an array of other health-promoting nutrients, including the minerals calcium, iron, magnesium, potassium, selenium, copper and zinc.
Modern Methods to Support Health-Conscious Consumers
Fermented soy’s outstanding potential can now be fully realized through modern technological methods. These methods include: certification for organic growing and processing; modern food processing and fermentation techniques; and genetic ID testing.
1. The organic integrity of the soybean can becertified through every step of its growth and production. The certification process is performed by independent, third party regulators of organic food systems such as QAI (Quality Assurance International Organic Certification) and OCIA (Organic Crop Improvement Assoc.). These certifying agencies can inspect the land and production practices of farmers, the post-harvest facilities preparing the product, and the processing and handling facilities transforming the product.
2. Soybeans can be quick dried, pressure-cooked, ground, fermented with lactobacillus acidophilus bacteria and freeze dried. Then a sample batch can be sent to an independent laboratory for certificate of analysis, heavy metal testing and a microbiological profile.
3. Genetic ID testing can now identify genetically modified organisms (GMO’s) to provide assurance of Non-GMO soy foods. Many top scientists around the world are expressing their concerns regarding genetically manipulated crops/food ingredients. Some scientists have signed a document calling for a moratorium on genetically-manipulated crops. For more information please see the following website: http://www.twnside.org.sg/title/world-cn.htm.
Modern fermentation methods render the same natural ratio of protein, fat and carbohydrate as cooked, fermented soybeans. These methods provide the bioavailability, potency and nutritional advantages of fermentation in a convenient powder-based form.
By successfully emulating the healthy food preparation and consumption habits of the Far East, namely a moderate intake of traditional (organic) and often-fermented soy products, we may be able to reap the benefits of a traditional Asian diet. This may mean the prevention of some forms of cancer, heart disease, osteoporosis and menopausal symptoms.
Steps to Obtain the Most Benefit from Soy Products
First, learn which soy products and ingredients to use and which to avoid. Fermented products such as tofu, tempeh, miso, natto, tamari, shoyu and fermented whole soybean powder, when organic, are the healthiest forms of soy. Genetically manipulated soy ingredients should be avoided whenever possible. In the U.S. and Canada, almost all soy that is not referred to on the label as organic has been genetically manipulated. It is best to avoid hydrolyzed soy protein and eliminate the use of all soy formulas and foods in infants and very young children.
Second, learn about the benefits of traditional soy products and the benefits of other legumes (beans). There are other legumes that can play a very important part of a healthy diet. Societies that use significant amounts of soy also use other legumes as part of a more balanced diet.
Third, locate health food stores or natural food markets in your area, which sell organic fermented soy products and other products with organic fermented soy ingredients.
Fourth, learn how to prepare soy dishes. It is relatively easy to cook with tofu, tempeh, miso, tamari, shoyu, soymilk, and natto. Fermented soy powder can be made into nutritional shakes and smoothies or included in pancake mix, muffins, breads and other baked goods. Cookbooks and recipes can make using soy even easier. The following is a good website for ordering cookbooks: http://www.soyinfo.com/cookbook.shtml#soy
RoseMarie Pierce, B.Sc.Pharm, earned her degree in Pharmacy from Dalhousie University in 1972. After extensive studies in herbal and nutritional medicine, RoseMarie integrated these disciplinary practices with her pharmacy education to become Canada’s first Holistic Pharmacist.