It’s simple, basic and desi. Fermented rice is an integral part of the Indian diet for centuries. People from the rice eating states have their own dishes with fermented rice. In rural India, farmers start their day with overnight soaked leftover fermented rice. On the other hand idli, dosa, uttapam, selroti are popular breakfast items. No, the list does not end yet. People celebrate festivals with various types of pitha, haria, and other rice alcohol.
Fermented rice is there in all most every Indian culture irrespective of socioeconomic differences. This traditional food started getting scientific attention in the last two decades. Extensive research is being conducted worldwide.
By the way, do you know there are more than 5000 fermented foods consumed worldwide? Yes, you read it right! It’s FIVE THOUSAND. (1)
Rice fermentation can be of two types –
- Acid fermentation (eg- idli, dosa, panta/ pokhal bhat, etc) or,
- Alcohol fermentation (fermented rice liquor – Haria, apong, jau, etc)
Here in this blog, we will discuss the health benefits of fermented rice as well as how many ways you can ensure its goodness in your daily diet.
7 Benefits of fermented rice –
Fermentation is probably the first food biotechnology that people have figured out. Fermentation is a process where we create a favorable condition so that microorganisms can grow over a food substrate. Generally, rice, wheat, pulse, fish, meat, fruits; vegetables are used as the substrate.
Sometimes you don’t need to add any culture or starter (active microorganism eg- yeast) to the substrate to initiate the process. Fermentation takes place spontaneously gathering bacteria from the air. This is what happens when you make the rice batter for idli, dosa, or even keep the leftover rice overnight. In some cases, you need to add the starter/ culture to encourage the growth of the microorganisms. Eg- rice alcohol.
The bacteria start growing to utilize the carbohydrate (sugar) of the food. With time and controlled room temperature, the growth rate of microorganisms increase and bring many changes in food, like –
- Nutritional changes – change in quantity and quality of nutrients and anti-nutritional factors
- Functional changes – formation of many active compounds which provide multiple health benefits
- Sensory changes – the colour, texture, aroma, taste of the food altered
Each of these three changes ensure multiple health benefits as follows –
Nutritional changes –
1.Rice carbohydrate become available and easily digestible –
Rice contains approx 70% carbohydrates. Starch (the carbohydrate) in rice favors the growth of microbes. (3) These microbes either come from nature spontaneously or by adding a culture. These microbes start creating metabolites and enzymes which further encourage the growth of the microbes and prevent the growth of the pathogens (a microorganism that may cause disease). Most common microorganism developed in rice is lactic acid bacteria (LAB), lactobacilli, bifidobacteria, yeast, and molds. (4)
These lactic acid-producing bacteria produce glycoside hydrolase enzyme which converts the polysaccharide or indigestible form of complex carbohydrate into its simpler form. The yeast and molds help to break down the starch into maltose and glucose by producing amylolytic (carbohydrate splitting) enzymes.
Therefore the form of carbohydrates in fermented rice turned into an easily digestible form and become light on the stomach. Research shows that the carbohydrate content of rice gets reduced after fermentation. (2)
2. Increase the protein and reduce the fat content
Lactic acid bacteria present in rice during fermentation enhance the concentration of essential amino acid. (2) On the other hand, yeast present in fermented rice releases proteolytic (protein breaking) enzymes which increase protein availability.
Fermentation reduces the fat content in rice. The microorganisms produce lipolytic (fat splitting) enzyme which breaks down the fat into small chain fatty acids and becomes more available for absorption.
3. Fermentation improve the fibre, vitamins and mineral content of the rice
Isn’t this sound like dream come true? Yes, the study shows the fiber and micronutrient content increase to many folds after fermentation.
The complex fiber and micronutrients get released from their bind form and become more available for absorption. Vitamin B1, b2, folic acid, vitamin C, A, E-content increased. Bioavailability of zinc, iron, and calcium improved. In addition, it also boosts the good gut bacteria to synthesize vitamin B12 and vitamin K. (1)
Table 1 : How fermentation change the nutritive value of white rice flour – (2)
4. Reduce the anti-nutritional factors
Rice contains anti-nutritional factors like lectin, trypsin inhibitors, phytate, etc which inhibits the absorption of micronutrients in our body. Fermentation helps to reduce these anti-nutritional factors and as mentioned earlier, improve the availability of micronutrients like calcium, iron, etc. (1)
5. Fermentation improve your gut health
Once you eat sugar or any ultra-processed food like biscuits, instant noodles, pasta, bhujia, etc., it not only gives you empty-calorie, sugar, and salt but also encourages the growth of bad bacteria which thrive on the sugar in the gut. Fermented rice just does the opposite.
Fermented rice contains multistrain probiotics, which create a favorable environment for native gut bacteria and prevent the growth of pathogens (disease-producing microorganisms). This keeps the gut microbiome healthy and reduces inflammation. (1)
6.Improve epithelial lining and boost immunity –
Regular consumption of fermented rice helps to improve your gut health. The good bacteria of your gut helps in proper digestion, absorption, produce different metabolites like short-chain fatty acids (butyrate) which gives a positive effect on your epithelial lining of the gastrointestinal tract and also helps to improve immunity.(5), (6)
7. Fermented rice as a functional food
You must be thinking what is functional food, right?
A food become functional food when –
- the element which may cause health hazard in the food is eliminated or replaced, and/or,
- the concentration of any present nutrient increases, and/ or,
- any component which has a beneficial effect get added to the food and/ or,
- bioavailability/ stability of the food improved (7)
Fermented rice is a functional food for many reasons. After fermentation, rice gets enriched with various antimicrobial, antioxidant substances, metabolites like phenolics, flavons, vitamin E, phytosterol, linoleic acid, anthocyanins, proanthocyanins etc. (8) (9)
These body-friendly bacteria play an important role in reducing cholesterol, improve peristalsis, transit time and prevent diarrhea. Regular consumption of fermented rice also helps to takes care the lactose intolerance. Fermented rice has the property to suppress cancer of the colon, liver, stomach, bladder, and esophagus. (10), (11)
Sensory changes –
8. Add variety and reduce cooking time –
When rice gets fermented, it may involve acidic fermentation or, alcoholic fermentation, or both. Generally, we do some pre-treatment of rice like soaking, grinding, or boiling which relaxes the tight starch structure of the rice grain and slowly dilutes the antinutritional factors.
When we make the rice batter with or without dal and allow fermenting, carbon-di-oxide and other gases start forming inside the batter. This brings changes in the texture. Food becomes soft and spongy. The release of metabolites like glycosides, esters, fusel alcohol, acids, etc brings a change in the taste and aroma of the fermented rice. (1)
Rice fermentation does not only bring changes in the sensory attributes like- texture, taste, aroma, etc but also significantly reduces the cooking time.
How to use fermented rice in the Indian diet?
As mentioned earlier, fermented rice is a part of the Indian diet for centuries. All most every community has its own time-tested recipe of fermented rice. Two types of fermentation generally take place on rice –
- Acid fermentation – Here yeast and bacteria use rice starch and sugar to produce lactic acid and other metabolites.
- Alcohol fermentation – Here generally yeast or bacteria or any starter/ culture is added to the rice where the microorganism use starch and sugar of the rice to produce ethanol and carbon dioxide.
In both types of fermentation generally room temperature is maintained for a specific time. Sometimes the choice of the container also makes a difference in the outcome of the final product.
Fermented rice as food –
Table 2: Fermented rice dishes (acid fermentation) popular in various part of India and their health benefits – (1)
|Fermented Rice item||What is it?||Where it is popular?||Main ingredient||Fermentation time||Beneficial for|
|Idli||Savoury rice cake||Across India||Rice, Urad dal – 4:1||8-12 hrs||Weight loss, high BP, heart disease, constipation (12), (1)|
|Dosa||Crispy flat pancake||Across India||Rice, Urad dal – 2:1||8-12 hrs||Pre diabetes, diabetes, Rheumatoid arthritis, neural disorder, gluten intolerance (12), (13)|
|Uttapam||Thick slightly crisp pancake||South India||Rice, Urad dal – 3:1||5-6 hrs||Pre diabetes, diabetes, reduce cholesterol, heart disease, weight loss (14).|
|Dhokla||Soft, spongy, rice cake||South & West India||Rice, Urad dal/ chana dal – 4:1||5-8 hrs||Pre diabetes, diabetes, reduce cholesterol, heart disease, weight loss (15), (16)|
|Appam/ Chitou||Flat , thin pancake||Kerala, Odisha||Rice, Urad dal||5-6 hrs||Heathy snack (17)|
|Pitha||Rice pancake with sweet/ savory filling||Bengal, Odisha, Jharkhand, Bihar||Rice, Urad dal||8-12 hrs||Festive food|
|Adai & Vada||Fluffy donut||South India||Rice, chana dal, moong dal, tur dal, urad dal||5-8 hrs||Adults and children as healthy snack (18)|
|Selroti||Spongy rice bread||Hill area – Himachal Pradesh, Darjeeling, Sikkim, Nepal, Bhutan||Rice, wheat flour (3:1), sugar, butter/ fresh cream||3-4 hrs||Protecting dyslipidemia, cardiac disorder (21)|
|Ambeli||Slurry drink||Central India||Rice, ragi, buttermilk||14-16 hrs||Adults and children for containing easily digestable protein (12), (19)|
|Sour rice/ Panta bhat/ pokhalo/ Pakhala/ Pazhaya Soru/ Pazhaya sadam||Overnight left cooked rice||Bengal, Odisha, Assam, Chattisgarh, Tamil Nadu||Rice, Curd/ Buttermilk is optional||8-14 hrs||Restore healthy microbes, good for duodenal ulcers, infectious ulcerative colitis, Crohn’s disease, irritable bowel syndrome, candida infection, celiac disease, etc. (17), (22)|
|Babru||Flat rice bread||Lahaul, Spiti in Himachal Pradesh||Rice Flour||3-4 hrs||Improve digestibility (20), (19)|
|Sez||Slurry cooked rice – probably a mix of acid & alcohol fermentation||Himachal Pradesh||Rice, use a starter called balam. Keep the mixture in earthen pot & kept in dark||Minimum 24 hrs –||Festive food|
Easiest way to add prebiotic and probiotic in diet –
Try sour rice. It needs no cooking skills. Take some extra rice in a container (preferably earthen pot). Add some drinking water. Make sure the rice is soaked in water. Put the lid on. Leave it overnight at room temperature. Next day morning eat the rice (at least 2-3 spoons) along with the water. You may feel like adding some lemon juice, salt, onion, green chili with it. Some may use curd or buttermilk too. Go by your tradition.
Fermented rice as beverages –
Table 2: Fermented rice beverages (alcohol fermentation) popular in various part of India and their health benefits – (1)
|Fermented Rice item||Where it is popular?||Main ingredient & starter||Fermentation time||Alcohol percentage||Beneficial for|
|Haria||Bengal, Jharkhand, Odisha||Low grade boiled scorched|
Bhakhar (Microbes+ Plant residue)
|3-5 days – Keep the mixture in earthen pot & kept in dark, dilute with water, sieve and serve||3-4% v/v||Protect from dysentery diarrhea, amebiasis, |
acidity. Rich in antioxidants (23), (24), (25)
|Apong||North east India||Rice, ash of paddy husk & straw |
Ipoh or epop (plant parts + old ferments)
|20 days||7.5 – 18.5%||preventing formation of kidney stone (26), (27)|
|Jau||North east India||Cooked boiled rice Amao or angkur (microbes + plant parts)||3-5 days||18% v/v||keeps the body relaxed and may prevent jaundice and urinary disorders (26)|
|Judina||North east India||Glutinous variety of rice Umhu or humao (rice + plant parts)||3-4 days||16% v/v||It has anti-inflammatory, anti-allergic, antioxidant, anti-bacterial, anti-fungal, anti-spasmodic, hypolipidemic, neuroprotective, anti-diabetic |
hepatoprotective, hypotensive, and antiaging, potentialities (29) (30)
|Zutho||Nagaland||Rice flour |
Khekhrii or grist (dust of sprouted unhulled rice)
|2-3 days||5% v/v||boost immunity, control insulin level, , prevent loss of appetite, lower LDL level, helps in wound healing, and prevent infection (26) (31)|
|Bhaati Jaanr||North east India||Glutinous rice |
Marcha (rice dust + plant parts + old marcha)
|2-8 days||5.9% v/v||for sick & postnatal women to regain physical strength (28)|
|Rice Jann||Uttaranchal & Himachal Pradesh||Cooled boiled Rice Balam or balma (microbes + plant parts)||6-10 months||10% V/V||energy rich refreshing drink and known to provide protection against cold (31)|
- Be aware of the difference between food spoilage and fermentation
The difference is very basic. When food gets spoiled, a growth of unwanted pathogens makes the food off-flavor, off-taste, and off-texture. Sometimes these pathogens may create serious health hazards like severe diarrhea, vomiting, stomach ache, headache, etc. So stay alert. Any type of change from usual sensory attributes should be taken seriously. If needed don’t think much to discard the food in total.
- Fermented rice foods and beverages contain a high level of histamine (an organic nitrogenous compound). People having histamine intolerance should avoid fermented foods and beverages.
- Fermented foods are also rich in potassium. Therefore patients suffering from chronic kidney disorder and not on dialysis should also avoid fermented foods and beverages.
Fermented rice is one of the best functional food in the regular Indian diet. It is healthy for most people. So feel free to add the fermented rice dish as per your tradition. Fix your dose of natural probiotic and prebiotic ensuring fermented rice in your daily diet. Start taking your dosa, idli, dhokla, or even panta bhat seriously. You will be fine.