Fermentation is one of the oldest forms of food preservation technology in the world. Many families around the world, especially in rural communities have prepared and consumed indigenous fermented foods such as beer, porridge, condiments, cheese and wine. They are staples to the diet and strongly linked to culture and tradition, and some are served at weddings and funerals as part of rituals. For instance, in many African countries cassava products gari and fufu are a major component of the diet of more than 800 million people and in some areas constitute over 50% of the diet; sorghum and millet are fermented to make daily porridge (ting, incwacwa) and beer; and in Asian countries from Indonesia to Japan soy is a fundamental ingredient to the diet and has spread globally as health foods.
The warm, dark and wet process
Fermentation is a relatively efficient, low energy preservation process, which keeps food safe
& preserved for long-term storage, decreasing the need for other forms of preservation such as refrigeration. It is therefore ideal to use in remote areas where access to sophisticated equipment is limited.
The process happens naturally because it relies on microbes found in the environment. This is called spontaneous fermentation. This magic trick results in food cooking itself using no outside energy source. The final product has live bacteria that replenish the gut microbiome.
There are many forms of fermentation. Here are some of the fermented foods:
Alcoholic: beer, wine
Non-alcoholic: teas, vinegar-based drinks, kombucha or buttermilk
Drinks: Coffee, cacao, tea and wine
Grains: Sorghum, Millet & Maize (Ting, incwancwa, mageu, beer, ogi), sourdough
Dairy: cultured dairy: Cheese, maas, kefir, yoghurt
Non-dairy: coconut milk
Soya: nato, miso, tempeh, tofu
Pastes: seasoning, condiments, curries, stews, pickles and sweets
Condiments: ketchup, relish, salsa, chutney & hot sauce
Vegetables: Sauerkraut, Kimchee, beets, radishes, tomato, onion, garlic, green beans, olives
Roots: Cassava, yams and plantain
Meat & Fish
The natural live bacteria develop and improve palatability, flavour and nutrition than before by:
Creating new layers of flavour e.g. in aged cheese, beer and vegetables
Increasing acidity close to succulent tartiness in vinegar and sour milk
Turning hard-to-eat raw vegetables such as cabbage, carrots, beet, marrow into a treat without any cooking
Dairy milk when soured is made tastier with increased shelf life. It is better digested because lactose (milk sugar) is turned into lactic acid by bacteria that feed on it. Most people who are lactose-intolerant produce inadequate amounts of lactase in the gut, the enzyme that digests lactose.
Raw milk is fermented spontaneously or with a bacterial culture, whereas pasteurised milk is fermented with a bacterial culture because pasteurisation reduces the natural bacteria in milk
Good bacteria in fermented food act as antibiotics by destroying the harmful germs in food and the gut
Fermenting foods increased vitamins and mineral content of foods
Fermentation decreased anti-nutrients such as phytates in grains and legumes, optimised protein and carbohydrates digestion
Fermentation reduces mycotoxin levels. Mycotoxins are toxic compounds that are naturally produced by certain types of moulds (fungi) on foodstuffs such as cereals, dried fruits, nuts and spices.
Fermentation lowers carbohydrate contents of food
Because the fermented foods are predigested, they are used in indigenous communities as weaning foods and nourishment during ill health
Fermented foods increase gut microbial diversity, improve immune responses and reduce inflammation.
Fermented foods give better satiety and have been linked to a reduction in blood pressure, bad cholesterol and sugar levels
They are also linked to a reduction in anxiety and depression.
The Impact of Westernised Diets
With modernisation, diets have transitioned from indigenous, local and wholesome diets to overly processed, fast and glamorously packaged foods. This included the adoption of pasteurised milk from the 20th century and a tremendous abandonment of raw milk and its by-products such as sour milk and raw milk cheeses.
This resulted in a loss in traditional food cultures and powerful probiotics & enzymes along with the beneficial bacteria. Traditional food fermentation represents a valuable cultural heritage in many regions of the world that should not be lost and has the valuable potential of previously undiscovered strains.
The future of fermented foods
Although fermentation of foods has been in use for thousands of years for the preservation and improvement of a range of foods, the microbial and enzymatic processes responsible for the transformations were, and still are, largely unknown.
Now science looking back at ancient techniques to understand healthy probiotics. During the past decade, there’s been increasing scientific interest in studying gut microbes in westernised and non-westernised populations. The results have shown that urbanisation plays an important role in human health and disease, especially in non-communicable diseases. Research is interested in understanding which features of the human lifestyle and biology change as people move to cities.
Improving the understanding of fermented products
For fermented products such as cheese, bread, beer and wine, which are produced on a commercial scale, a good understanding of the microbial processes has been developed. For most products, knowledge of the processes involved is poor.
Understanding the fermentation processed is not intended to standardise the processes and lose the huge diversity in microprobes and recipes. There is tremendous scope and potential for the use of micro-organisms towards meeting the growing world demand for high-quality food.
Fermented foods, such as yoghurt, kefir, fermented cottage cheese, fermented vegetables, vegetable brine drinks, kombucha, and other fermented non-alcoholic drinks, have gained increasing popularity on the market shelves and consumers’ baskets. When shopping especially in supermarkets, take note that some of these ‘fermented’ products available in stores, such as some sauerkrauts are pasteurised, thereby killing the live bacteria.