Ragi - A Super Grain & Potential Need of its Fortification

schedule 6 min read
Topic(s): Malnutrition

Micronutrient deficiencies particularly that of iron early in life is often linked with adverse outcomes in growing infants and later life. In India, in most of the regions, ragi is used as one of the complementary foods for infants due to its quality of being a powerhouse of nutrients such as proteins, iron, calcium, phosphorus, and many more. Along with the positive attributes of ragi, the various processes involved in making it in a consumable form, reduces its nutrient densities, thereby resulting in the decreased bioavailability of various nutrients. Micronutrient fortification in such scenario has proven beneficial in increasing the benefits of the major cereal by contributing to bridge the nutrient and energy gap created by processing methods as well as eliminate the potential contaminants present as part of crop harvesting.

Worldwide, finger millet or ragi as it is commonly referred to in India is the 4th most important millet after sorghum, pearl millet, and foxtail millet. In India, ragi is the principal food grain for the rural population especially in south Indian states including Tamil Nadu. It has superior quality protein, essential amino acids, vitamin A, B complex vitamins, iron, calcium, and phosphorus. Ragi is a gluten-free food, commonly used in the preparation of nourishing porridges for growing children.

Nutritional Benefits of Ragi       
From the nutritional perspective, ragi has been perceived as a potential “super cereal” or “super grain” because it is substantially high in minerals and micronutrient density compared to the other major cereals such as rice and wheat.  Ragi is a powerhouse of nutrients because of the high content of macronutrients such as carbohydrates (65%–75%), protein (5%–11.3%), fat (5.2%), dietary fiber (18%) and micronutrients such as minerals (2.5%–3.5%) including calcium (344%) and iron (3.9%). Of the total amino acids, ragi contains about 44.7% essential amino acids. Further, tryptophan, cystine, and methionine that are deficient in major cereals are present in a good amount in ragi. Tryptophan helps fight anxiety, depression, and insomnia at the same time controls weight gain by reducing excess appetite. Owing to its high nutritional value, ragi exhibits anti-diabetic, anti-diarrheal, anti-inflammatory, antioxidant and antimicrobial properties.

Impact of Processing on Nutritional Benefits of Ragi    
Ragi is processed in many different ways to render it edible and to develop food formulations that are nutritious and more attractive in appearance, consistency, flavor, and taste. Ragi can be de-braned, flaked, sprouted, milled, popped, or puffed. However, during some of these processing methods, nutrient-rich parts of the grain (germ, aleurone layers, seed coat) are displaced resulting in loss of nutrients such as calcium, dietary fiber, polyphenols and so on.
Most mothers use common household methods to process malting of ragi to use as one of the complementary foods. These processes include steeping, sprouting, drying, toasting and milling into flour. However, these processing methods come with some drawbacks such as steeping for <10 h may not be enough to sufficiently hydrate the grains; sprouting may be hampered if grains are wrapped tightly; milling can increase the fiber content of the infant food formulations and may also impart bitterness to the prepared food. Also, losses of nutrients such as proteins, iron, calcium, and phosphorus have been reported during some of the cooking processes. Besides this, there are also concerns with the nutrient quality of packed ragi powder available in the market, there may be uncertainties in it being safe for consumption by infants. Weed infestation is a serious threat to ragi cultivation further may make the purity of packed ragi questionable.

Antinutrients in Ragi and its Impact on Nutrient Bioavailability
In addition to nutrients, ragi also contains antinutrients such as tannins, trypsin inhibitors, phytate, phenolic compounds etc., which may lower nutrient digestibility and absorption. According to a study, about 50% of the iron in the diet is bound to tannins and about 41% of phytate is bound to phosphorus as phytic phosphorus. Further, antinutrients such as phytates, phenols, and tannins negatively influence in vitro protein digestibility.  Therefore, majorly cereal- or millet-based foods have poor nutrient bioavailability specifically iron, increasing the risk of iron deficiency and anaemia despite of inherently high nutrient content of the cereal.  Such foods when fortified with micronutrients have the potential to increase the nutrient density and bioavailability by neutralizing the effect of anti-nutrients and containing nutrient enhancers like vitamin C for increasing iron absorption. This results in reduced risk of multi-micronutrient deficiencies and improved the overall health of children. Data from the clinical study by Prieto & Detzel conducted in India and from the Feeding Infants and Toddlers Study conducted in various countries, establishes significantly higher mean iron intake in children who consume iron-fortified infant cereal than non-consumers, thereby lowering the risk of iron deficiency and iron deficiency anaemia.

Conclusion        
Although ragi is rich in macro- and micronutrients, the rigorous process of processing coupled with the inherent presence of anti-nutrients negatively impact the absorption of key nutrients like iron, resulting in the decreased bioavailability of the nutrients and thus resulting in creating a nutrient gap. Therefore, fortified ragi may be a potential strategy to bridge the gap created by non-fortified ragi. This helps in retaining the benefits of ragi as well as enhancing its nutritional benefits and making it safe for the consumption by infants of quality feed by eliminating the contaminants.

References

  1. Chandra D, Chandra S, Pallavi, et al. Review of finger millet (Eleusine coracana (L.) Gaertn): A power house of health benefiting nutrients. Food Sci Human Wellness. 2016;5:149–155.
  2. Patel I, Patel K, Pinto S, et al. Ragi: A powerhouse of nutrients. Res Rev J Dairy Sci Technol. 2016;5(3):36–47.
  3. Kumar A, Metwal M, Kaur S, et al. Nutraceutical value of finger millet [Eleusine coracana (l.) Gaertn.], and their improvement using omics approaches. Front Plant Sci. 2016;7(943):1–14.
  4. Sajilata G, Singhal RS, Kulkarni PR. Weaning foods: A review of the Indian experience. Food Nutr Bull. 2002;23(2):208–226.
  5. Utta DP, Pradesh VE, Singh TK. Chemical composition of Finger millet of food and nutritional security. Int J Food Sci Microbiol. 2015;3(6):092–098
  6. Sarita, Singh E. Potential of millets: Nutrients composition and health benefits. J Sci Innovative Res. 2016;5(2):46–50
  7. Finn K, Callen C, Bhatia J, et al. Importance of dietary sources of iron in infants and toddlers: Lessons from the FITS study. Nutrients. 2017;9(733):1–9.
  8. Prieto, Alberto & Detzel, Patrick. Association between feeding types and haemoglobin concentrations in India. 2015.