Fermentation of food takes place through controlled microbial growth. In the past, food was fermented to preserve it and to increase its shelf life. Food fermentation takes place by two methods.
- Wild Ferments: Food ferments naturally by the action of microorganisms that are already present in raw food or the environment.
- Culture Dependent Ferments: Foods that can be fermented by the addition of starter culture. Starter cultures can be obtained from previous fermented batch (backslopping) or commercially available starters.
Common Fermented Foods
Fermented foods around the world, include:
- Yogurt (made from milk)
- Kefir (made from milk)
- Kimchi (fermented cabbage with seasoning)
- Sauerkraut (fermented cabbage)
- Kombucha (fermented tea)
- Tempeh (Indonesian fermented soybeans)
- Natto (Japanese fermented soybeans)
- Miso (fermenting soybeans with salt and koji)
- Cheese (made from milk)
- Sourdough bread
Benefits of Fermented Foods
- Fermentation is a biological method of food preservation. Fermentation of food produces organic acids such as acetic acid and lactic acid. Acidic environment is unfavorable for the growth of many pathogenic and spoilage microorganisms.
- Taste and texture of fermented foods improve when compared to starting materials.
- It promotes human health. Clinical studies have revealed strong associations between consumption of fermented dairy foods and weight maintenance, reductions in risk of cardiovascular disease, type 2 diabetes.
- Fermented food consumption can alter mood and brain activity.
- Fermented foods provide living microorganisms to the gastrointestinal (GI) tract.
Can You Purchase Fermented Foods at Stores?
Adding it to the diet is easy. You can find naturally fermented foods at grocery stores and fermentation is also easy and safe to do at home.
All fermented foods are not equal. For instance, cheese and yoghurt both are fermented products but it is the only yoghurt that will provide live microbes. Similarly, live cultures are also found in kefir (yogurt-like drink), kimchi, and sauerkraut (Korean pickled vegetables).
When shopping for pickled vegetables always check labels, if ingredients contain vinegar then it does not contain live microbes. Always look for the word “naturally fermented” on the label.
Fermented foods are produced with microorganisms, but not all fermented foods contain live microorganisms when consumed. Heating and processing, kills the live microbes. Shelf-stable products stored at room temperature, such as jarred sauerkraut and pickles, do not contain live microorganisms. However, refrigerated versions of sauerkraut and pickles may contain live microorganisms. Similarly, the live cultures present in sourdough do not survive the baking process.
Difference between Fermented Foods and Probiotics
Both fermented and probiotic foods are made with microorganisms. However, not all fermented foods are considered as probiotics. WHO definition of a probiotic is “Live microorganisms which when administered in adequate amounts confer a health benefit on the host”. For example, both yogurt and cheese are fermented foods, but only yogurts that contain enough live and active cultures (probiotics).
Yogurt
Yogurt is one of the sources of probiotics. Milk helps make yougart with fermented by probiotics, mainly lactic acid bacteria and bifidobacteria.
Health benefits of eating yoghurt,
- Improved bone health
- Improved digestive health and gut microbiome, kills harmful bacteria
- Helps relieve the symptoms of irritable bowel syndrome (IBS)
- Suitable to lactose intolerants, because lactose in the milk changes to lactic acid.
- Beneficial for people with high blood pressure
- In children, yogurt may help reduce diarrhea caused by antibiotics
However, not all yogurt contains live probiotics. During processing, live bacteria dies. For this reason, make sure to choose yogurt with active or live cultures.
Kefir
Kefir is a fermented probiotic milk. It is made by adding kefir grains to the milk (traditionally made with cow’s milk or goat’s milk). Kefir grains are cultures of lactic acid bacteria and yeast. Kefir tastes sour like yogurt but it has a thinner consistency.
- Kefir is more probiotic than yoghurt
- Kefir contains probiotics “Lactobacillus kefiri”, which protect against harmful bacteria
- Improved bone health and lower risk of osteoporosis
- Help with some digestive problems
- Like yogurt, kefir is also well tolerated by people who are lactose intolerant
See Also: Gut Microbiome: Crucial for Health
Sources
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