Thanks to its many advantages, fermentation is back in demand.
If you grew up in the 1970s, you might remember when homemade yogurt became all the rage in the burgeoning health-food scene. As it was with many early health-food trends, yogurt’s healthy image was more anecdotal than backed by science. Today, however, we know that yogurt’s health-promoting benefits are a result of fermentation-the production of live cultures, which have been scientifically proven to promote healthy gut ecology.
The process of fermenting food is an ancient ritual, performed by humans for thousands of years. Its original purpose was to preserve food against spoilage. Many ethnic cultures still eat fermented foods, such as Japanese miso, tempeh, and natto; Korean kimchi; and Mexican pozol. Unfortunately, with the exception of yogurt, fermented foods are not commonly consumed in the Western diet.
Luckily for us, however, a number of food trends are converging to revitalize the art of fermenting foods. The “Do It Yourself” movement has encouraged consumers to make everything at home, such as cheese, jam, beer, and (again!) yogurt. The emergence of the raw food movement has also increased awareness of fermented foods because cultured vegetables are a component of raw food diets. Add to those trends our continued embrace of ethnic cuisine and the food journalist Michael Pollan-inspired shift towards “know what you eat,” and what you get is a culinary climate such that Sandor Katz’s 500-page manifesto called The Art of Fermentation became a New York Times bestseller.
From a chemistry standpoint, fermentation is a simple reaction: using microorganisms, it is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids. Lactobacillus species are the most commonly used microorganisms, used to make foods like yogurt and sauerkraut. In addition to the unique flavors produced by lacto-fermentation, there is also the probiotic benefit of the Lactobacillus species themselves.
But the probiotic benefit is not the only health reason to consume fermented foods and ingredients. Unlike fermented foods, whose main health benefit is their probiotic activity, the health benefits of fermented supplement ingredients are more often a result of the chemical reactions that occur during the fermentation process. For instance, fermentation actually “pre-digests” complex foods by breaking them down into more readily absorbable amino acids and simpler sugars. Certain foods may have excellent nutritional profiles, but are difficult for humans to digest. Cereal grasses are a good example. Cereal grasses are defined as the young grass stage of the wheat, barley, alfalfa, or oat plant. At this young, green stage, the cereal plant is much more nutrient dense than the mature plant, containing many times more B vitamins, minerals, chlorophyll, and antioxidants. However, the nutrients are encased in cellulose plant cell walls, and humans cannot digest cellulose. Fermentation of cereal grasses is an excellent way to break down cellulose. This is exactly what happens in the “second stomach” of a cow. Ruminants have a separate stomach chamber that breaks down plant materials with the help of
enzymes and bacteria.
Many cultures ferment grains, and studies also show that fermentation of grains increases levels of B vitamins1,2,3,4,5 and lysine.5,6 Fermentation also improves amino acid and vitamin composition2,5 as well as mineral bioaccessibility.4,5,7 Fermenting foods like beans, garlic, and tea has been shown to increase the potency of antioxidant compounds like polyphenols.8,9,10 In some cases, fermentation actually creates unique phytonutrients not present in the raw material.11
Fermentation can also eliminate “anti-nutrients” like phytic acid, a compound found in grains that blocks absorption of minerals,5,12,13,14 and lectins, toxins that interfere with digestion.14,15 Production of kimchi has even been shown to biodegrade pesticides.16
Another example of a beneficial consequence of fermentation is what happens when ginseng root is fermented. It is has been shown that ginsenosides from ginseng are transformed in the intestines of humans by colonic fermentation into an end-stage metabolite called Compound K. Compound K has been proposed to be the most bioavailable metabolite.17 Fermenting ginseng extract actually reproduces the fermentation environment in the colon, thus producing Compound K prior to consumption. Fermented extracts containing Compound K have been shown to have significantly higher and faster absorption in humans compared to non-fermented ginseng.18 Fermented ginseng extracts have also been shown to have the many adaptogenic qualities of ginsenosides, such as strong antioxidant,19 anti-stress,20 hepatoprotective,21 anti-allergy, and anti-inflammatory22 activities, as well as support for healthy glucose and lipid regulation.23
The focus of fermenting supplement ingredients is to promote an environment to maximize these chemical transformations; as such, a controlled fermentation process is necessary. Uncontrolled fermentation can have negative effects, such as loss of nutritional value and palatability as well as potential spoilage. Controlled fermentation, on the other hand, encourages the growth of particular microorganisms only to the point that achieves the desired effects, and then the fermentation is interrupted to stabilize the ingredients.
Fueled by both the increasing popularity of fermented foods and the science that goes beyond the probiotic health benefit of fermentation, the use of fermented supplement ingredients-from cereal grains and grasses, fruits and vegetables, and ginseng to soy-is the latest trend in new product development.
1. Capozzi V et al., “Biotechnological production of vitamin B2-enriched bread and pasta,” Journal of Agricultural and Food Chemistry, vol. 59, no. 14 (July 17, 2011): 8013-8020.
2. Chavan JK et al., “Nutritional improvement of cereals by fermentation,” Critical Reviews in Food Science and Nutrition, vol. 28, no. 5 (1989): 349-400.
3. Capozzi V et al., “Lactic acid bacteria producing B-group vitamins: a great potential for functional cereals products,” Applied Microbiology and Biotechnology, vol. 96, no. 6 (December 2012): 1383–1394.
4. Hemalatha S et al., “Influence of germination and fermentation on bioaccessibility of zinc and iron from food grains,” European Journal of Clinical Nutrition, vol. 61, no. 3 (March 2007): 342-348.
5. Haard N et al., “Fermented Cereals. A Global Perspective,” FAO Agricultural Services Bulletin no. 138 (1999).
6. Hamad AM et al., “Evaluation of the protein quality and available lysine of germinated and fermented cereal,” Journal of Food Science, vol. 44, no. 2 (March 1979): 456-459.
7. Famularo G et al., “Probiotic lactobacilli: an innovative tool to correct the malabsorption syndrome of vegetarians?” Medical Hypotheses, vol. 65, no. 6 (2005): 1132-1135.
8. Oboh G et al., “Changes in polyphenols distribution and antioxidant activity during fermentation of some underutilized legume,” Food Science and Technology International, vol. 15, no. 1 (February 2009): 41-46.
9. Sato E et al., “Increased anti-oxidative potency of garlic by spontaneous short-term fermentation,” Plant Foods for Human Nutrition, vol. 61, no. 4 (December 2006): 157-160.
10. Jeng KC et al., “Effect of microbial fermentation on content of statin, GABA, and polyphenols in Pu-Erh tea,” Journal of Agricultural and Food Chemistry, vol. 55, no. 21(October 2007): 8787-8792.
11. Ciska E et al., “Glucosinolate derivatives in stored fermented cabbage,” Journal of Agricultural and Food Chemistry, vol. 52, no. 26 (December 29, 2004): 7938-7943.
12. Reale A et al., “The importance of lactic acid bacteria for phytate degradation during cereal dough fermentation,” Journal of Agricultural and Food Chemistry, vol. 55, no. 8 (April 18, 2007): 2993-2997.
13. Leenhardt F et al., “Moderate decrease of pH by sourdough fermentation is sufficient to reduce phytate content of whole wheat flour through endogenous phytase activity,” Journal of Agricultural and Food Chemistry, vol. 53, no. 1 (January 12, 2005): 98–102.
14. Reddy NR, “Reduction in antinutritional and toxic components in plant foods by fermentation,” Food Research International, vol. 27, no. 3 (1994): 281–290.
15. Hamad AM et al., “Evaluation of the protein quality and available lysine of germinated and fermented cereal,” Journal of Food Science, vol. 44, no. 2 (March 1979):456-459,
16. Cho KM et al., “Biodegradation of chlorpyrifos by lactic acid bacteria during kimchi fermentation,” Journal of Agricultural and Food Chemistry, vol. 57, no. 5 (March 11, 2009): 1882-1889.
17. Hasagawa H, “Proof of mysterious efficacy of ginseng: basic and clinical trials: Metabolic activation of ginsenoside: Deglycosylation by intestinal bacteria and esterification with fatty acid,” Journal of Pharmacological Sciences, vol. 95, no. 2 (June 2004): 153-157.
18. Jin H et al., “Pharmacokinetic comparison of ginsenoside metabolite IH-901 from fermented and non-fermented ginseng in healthy Korean volunteers,” Journal of Ethnopharmacology, vol. 139, no. 2 (January 31, 2012): 664– 667.
19. Ramesh T et al., “Effect of fermented Panax ginseng extract (GINST) on oxidative stress and antioxidant activities in major organs of aged rats,” Experimental Gerontology, vol. 47, no. 1 (January 2012): 77-84.
20. Kitaoka K et al., “Fermented ginseng improves the first-night effect in humans,” Sleep, vol. 32, no. 3 (March 2009): 413-421.
21. Lee HU et al., “Hepatoprotective effect of ginsenoside Rb1 and compound K on tert-butyl hydroperoxide-induced liver injury,” Liver International, vol. 25, no. 5 (October 2005): 1069–1073.
22. Yang CS et al., “Compound K (CK) rich fractions from Korean red ginseng inhibit toll-like receptor (TLR) 4- or TLR9-mediated mitogen-activated protein kinases activation and pro-inflammatory responses in murine macrophages,” Journal of Ginseng Research, vol. 31, no. 4 (December 2007): 181-190.
23. Yuan HD et al., “Beneficial effects of IH-901 on glucose and lipid metabolisms via activating adenosine monophosphate–activated protein kinase and phosphatidylinositol-3 kinase pathways,” Metabolism-Clinical and Experimental, vol. 60, no. 1 (January 2011): 43–51.