Not fresh, yet healthy6 min read . Updated: 12 May 2014, 07:45 PM IST
Fermented foods can be the deciding factor between good gut health and lackadaisical digestion
What’s not fresh and yet is really good for you? We are talking fermented foods—foods that have been kept around for a while, smell weird but are packed with nutrients. Fermentation has been used to preserve food in the absence of refrigeration, canning, preservatives and irradiation. But with the advent of modern techniques of preserving food, fermentation took a back seat. Here, we explore some facts about fermented foods and their health benefits.
How did it all start?
According to the 2012 book, The Art Of Fermentation: An In-Depth Exploration Of Essential Concepts And Processes From Around the World by Sandor Ellix Katz, “Fermented foods were not exactly human inventions; they are natural phenomena that people observed and then learned how to cultivate." In each geographic location, this depended on the plants and crops that grew in abundance and the different microbial communities that thrived in that environment. Places with difficult winters fermented foods during summer for winter and those with tropical weather conditions used fermentation as a way to save food that would otherwise spoil quickly in the hot weather.
Fermentation is the process where sugar/ starch in the food is broken down into alcohol or acid. Yeast fermentation involves a breakdown of sugar into alcohol, while bacterial fermentation converts carbohydrates to lactic acid. A few strains of organisms multiply quickly, outnumbering the other bacteria by producing bacteriocins which prevent the growth of other closely related bacteria, thereby preventing the food from spoiling. Food scientist and fermentation expert Keith Steinkraus writes in his 1995 book, Handbook Of Indigenous Fermented Foods—Second Edition, Revised And Expanded: “The process of acidic fermentation: (1) they render foods resistant to microbial spoilage and the development of food toxins, (2) they make the foods less likely to transfer pathogenic microorganisms, (3) they generally preserve the foods between the time of harvest and consumption, and (4) they modify the flavour of the original ingredients and often improve the nutritional value."
The process of fermentation takes 2-21 days, depending on the food used and the temperature of the surroundings.
The end point depends on the effect or the taste one is looking for. For example, idli batter takes around 8-10 hours to double in volume in moderate Indian weather.
Common fermented foods
Fermented foods are all around us. Dahi or yogurt is the most quintessentially fermented food found throughout the country. Rice and urad dal (black gram) batter is kept regularly in most south Indian kitchens to ferment, quietly harnessing the power of yeast to make fluffy idlis and crisp dosas.
Black or purple carrots, which make an appearance in winters in north India, are used to make a fermented drink called kanji, which gets its kick from coarsely ground mustard seeds. Baton carrots are added to a pot of water in which spices (ground mustard, chilli powder, black salt) are added and kept on a sunny windowsill to ferment for five-six days, after which the drink is ready.
Pakhalabhaat in Odisha, called panta bhaat in West Bengal, is a rice porridge where leftover rice is covered with water and left overnight to ferment. This lightly fermented rice is eaten the following morning with salt, lime and chillies. A similar preparation in rural Tamil Nadu is called pazhedhu saadham, which means old rice. Rice is immersed in water overnight to prevent spoilage and the next day, it is mixed with buttermilk and salt, and mashed to make a gruel.
Kerala’s toddy is made by fermenting the sap of palm trees. The sap turns into toddy, a drink with 4% alcohol, within 2 hours. If left for over 2 hours,the toddy turns into vinegar. Toddy is used instead of yeast in appams and other such dishes from this region.
Fermented foods eaten raw, such as sauerkraut, kimchi and yogurt, are rich in probiotics. A 2006 paper published in the Journal Of Applied Microbiology lists some of the beneficial effects of probiotics—they improve gut health and immune system, synthesize and increase the bioavailability of nutrients, reduce symptoms of lactose intolerance, decreasing the prevalence of allergy in susceptible individuals; and reduce risk of certain cancers.
New Delhi-based food and nutrition consultant Sangeeta Khanna, who blogs on healthy food at Healthfooddesivideshi.com, says that clients for whom such fermented foods have been made a part of their daily diet, notice better digestion and bowel movement, and alleviation and even disappearance of allergies.
Irritable bowel syndrome is mostly tackled by supplementing probiotics and prebiotics. Probiotics are live good bacteria present in fermented foods like yogurt but die when exposed to heat (cooking). Prebiotics are the insoluble fibre found in food that reach the colon unchanged. It acts as food for the probiotic bacteria in the colon. One can see improved skin and hair if there is improvement in the gut flora.
A study published online in 2006 in the European Journal Of Clinical Nutrition found that batters for idli and dosa with a rice-urad dal ratio of 2:1 and 3:1, respectively, had increased levels of iron and zinc.
A document published on “Guidelines For the Use of Iron Supplements To Prevent And Treat Iron Deficiency Anemia" on the World Health Organization website recommends germination and fermentation of cereals and legumes to improve bioavailability of iron by reducing the phytate levels. Phytate is an anti-nutrient that prevents absorption of many vital nutrients such as iron.
According to Mumbai-based Shonali Sabherwal, chef, macrobiotic nutritionist and author of The Beauty Diet—Eat Your Way To a Fab New You and The Love Diet, fermented foods strengthen the inner ecosystem. They help combat candidiasis, a common condition caused by overgrowth of yeast in the system due to poor eating habits and erratic lifestyle, which weakens the immune system and gives rise to health issues ranging from the common cold, migraine, allergies, skin problems and lethargy to bloating. Eating fermented foods helps break down meals daily for compromised digestive systems, and also helps strengthen the digestive system in general. They provide beneficial digestive enzymes, and also a good strain of beneficial bacteria in the gut, says Sabherwal.
How much is enough?
Sabherwal allocates 10% of the calories to fermented foods as a part of the daily diet prescribed for her clients. She recommends miso soup, pressed salad (see box for recipe), idlis and sauerkraut. Khanna, who is a stickler for local produce and all things desi, recommends kanji, seasonal pickles of radish or leafy greens pickle, yogurt, buttermilk, soaked poha with yogurt, panta bhaat or fermented rice gruel in summers.
Nandita Iyer is a nutrition expert who blogs on Saffrontrail.com
Consume 2-3 times a week
uHalf a cup sliced cucumber
uHalf a cup sliced cabbage
uHalf a cup red radish
uOne fourth a cup celery
uOne fourth a cup red onion
u1 tsp salt (sea salt or rock salt)
Mix all the vegetables with sea salt in a large bowl, and gently press and mix the vegetables until they wilt. Place a heavy lid on the vegetables and press down with a heavy weight. Allow to stand for 45 minutes to let water release from the vegetables. Discard the water and rinse with fresh filter water and eat.
—Shonali Sabherwal, chef and macrobiotic nutritionist, Mumbai.