FNS  Vol.2 No.8 , October 2011
Influence of Processing on Dietary Fiber, Tannin and in Vitro Protein Digestibility of Pearl Millet
Abstract: From the nutritional point of view, data on dietary fiber content, tannin and in vitro protein digestibility of processed millet is of importance, because millets are never eaten raw. Effects of commonly used traditional methods on dietary fiber, tannin content and %IVPD of two locally available pearl millet varieties (Kalukombu and Maharashtra Rabi Bajra) were investigated. The millet was subjected to various processing methods like milling (whole flour, semi refined flour and bran rich fraction) roasting, boiling, pressure cooking & germination respectively. Processing had little effect on the total dietary fiber (TDF) content in both varieties; however the bran rich fraction showed highest TDF content of around 29%. Tannins effectively lowered upon boiling and pressure cooking respectively, but significantly increased (P ≥ 0.05) upon germination. Although the % IVPD of the millet (45.5 – 49.3 g/100g) was low, it significantly increased upon milling (bran rich fraction), roasting and germination respectively.
Cite this paper: nullF. Pushparaj and A. Urooj, "Influence of Processing on Dietary Fiber, Tannin and in Vitro Protein Digestibility of Pearl Millet," Food and Nutrition Sciences, Vol. 2 No. 8, 2011, pp. 895-900. doi: 10.4236/fns.2011.28122.

[1]   F. O. Sade, “Proximate, Antinutritional Factors and Functional Properties of Processed Pearl Millet (Pennisetum glaucum),” Journal of Food Technology, Vol. 7, No. 3, 2009, pp. 92-97.

[2]   S. A. Sehgal and A. Kwatra, “Nutritional Evaluation of Pearl Millet Based Sponge Cake,” Journal of Food Science and Technology, Vol. 43, No. 3, 2006, pp. 312-313.

[3]   M. Malik, U. Singh and S. Dahiya, “Nutrient Composition of Pearl Millet as Influenced by Genotypes and Cooking Methods,” Journal of Food Science and Technology, Vol. 39, No. 5, 2002, pp. 463-468. doi:10.1016/S0733-5210(03)00016-X

[4]   K. G. Duodu, J. R. N. Taylora, P. S. Beltonb and B. R. Hamaker, “Factors Affecting Sorghum Protein Digestibility,” Journal of Cereal Science, Vol. 38, No. 2, 2003, pp. 117-131.

[5]   J. S. Hughes, E. Acevedo, R. Bressani and G. B. Swanson, “Effects of Dietary Fiber and Tannins on Protein Utilization in Dry Beans (Phaseolus Vulgaris),” Food Research International, Vol. 29, No. 3-4, 1996, pp. 331-338. doi:10.1016/0963-9969(96)00027-0

[6]   A. M. Maha Ali, A. H. El Tinay and A. H. Abdalla, “Effect of Fermentation on the in Vitro Protein Digestibility of Pearl Millet,” Food Chemistry, Vol. 80, No. 1, 2003, pp. 51-54. doi:10.1016/S0308-8146(02)00234-0

[7]   A. G. H. Ilham and A. H. El Tinay, “Effect of Fermentation on Tannin Content and in-Vitro Protein and Starch Digestibility of Two Sorghum Cultivars,” Food Chemistry, Vol. 53, No. 2, 1995, pp. 149-151. doi:10.1016/0308-8146(95)90780-B

[8]   P. Shawrang, A. A. Sadeghi, M. Behgar, H. Zareshahi and G. Shahhoseini, “Study of Chemical Compositions, Anti-Nutritional Contents and Digestibility of Electron Beam Irradiated Sorghum Grains,” Food Chemistry, Vol. 125, No. 2, 2011, pp. 376-379. doi:10.1016/j.foodchem.2010.09.010

[9]   E. N. Fombang, J. R. N. Taylor, C. M. F. Mbofung and A. Minnaar, “Use of γ-Irradiation to Alleviate the Poor Protein Digestibility of Sorghum Porridge,” Food Chemistry, Vol. 91, No. 4, 2005, pp. 695-703. doi:10.1016/j.foodchem.2004.06.042

[10]   Anon, All India Coordinated Pearl Millet Improvement Project, Annual Report 2009-2010, Mandor, 2010.

[11]   G. Asp, C. G. Jonson, H. Hollment and M. Slijestrom, “Rapid Enzymatic Assay of Soluble and Insoluble Dietary Fiber,” Journal of Agricultural Food Chemistry, Vol. 33, No. 3, 1983, pp. 476-82. doi:10.1021/jf00117a003

[12]   Association of Official Analytical Chemists (AOAC), “Official Methods of Analysis,” 10th Edition, Washington D.C., 1970, pp. 154-170.

[13]   W. R. Akeson and M. A. Stahmann, “A Pepsin-Pancreatin Digest Index of Protein Quality,” Journal of Nutrition, Vol. 83, No. 2, 1964, pp. 257-261.

[14]   N. Raghuramulu, M. Nair and S. Kalyansundaram, “A Manual for Laboratory Techniques,” National Institute of Nutrition, Indian Council for Medical Research, Jami-Osmania, Hyderabad, 1983.

[15]   P. Ramulu and P. Udayasekhara-Roa, “Effect of Processing on Dietary Fiber Content of Cereals and Pulses,” Plants for Human Nutrition, Vol. 50, No. 3, 1997, pp. 249-257. doi:10.1007/BF02436061

[16]   S. Mahadevamma and R. N. Tharanathan, “Processing of Legumes: Resistant Starch and Dietary Fiber Content,” Journal of Food Quality, Vol. 27, No. 4, 2003, pp. 289-303. doi:10.1111/j.1745-4557.2004.00620.x

[17]   R. H. Mathers, “Fermented Foods, Legumes: Chemistry, Technology and Human Nutrition,” Marcel Dekker, New York, 1989, pp. 161-163.

[18]   L. Dykes and L. W. Rooney, “Sorghum and Millet Phenols and Antioxidants,” Journal of Cereal Science, Vol. 44, No. 3, 2006, pp. 236-251. doi:10.1016/j.jcs.2006.06.007

[19]   V. D. Pawar and G. S. Parlikar, “Reducing the Polyphenols and Phytate and Improving the Protein Quality of Pearl Millet by Dehulling and Soaking,” Journal of Food Science and Technology, Vol. 27, No. 3, 1990, pp. 140-143.

[20]   S. B. Ahmed, S. A. Mahgoub and B. E. Babiker, “Changes in Tannin and Cyanide Contents and Diastic Activity during Germination and the Effect of Traditional Processing on Cyanide Content of Sorghum Cultivars,” Food Chemistry, Vol. 56, No. 2, 1996, pp. 159-162. doi:10.1016/0308-8146(95)00157-3

[21]   C. M. McDonough and L. W. Rooney, “The Millets,” In: K. Kulp, Ed., Handbook of Cereal Science and Technology, Culinary and Hospitality Industry Publications, New York, 2000, pp. 177-200.

[22]   S. Chopra and A. Sankhala, “Effect of Soaking and Sprouting on Tannin Phytate and in Vitro Iron in Under-utilized Legumes—Hosed Gram (Dolichos Biflorus) and Moth Bean (Phaseolus Aconitifolius),” Journal of Food Science and Technology, Vol. 41, No. 5, 2004, pp. 547-550.

[23]   E. Haslam, “Chemistry of Vegetable Tannins,” Academic press, New York, 1966.

[24]   E. E. Maeda, C. N. Sule and M. J. Samuel, “Effect of Sprouting on Bean Nutritional Quality,” In: S. Sefa-Dedeh, Ed., Proceedings of Seminar on Development of High Protein- Energy Foods from Grain Legumes, University of Ghana, Legon, 1991, pp. 62-74.

[25]   M. L. Price, S. V. Socoyoc and L. G. Butler, “A Critical Evaluation of the Vanillin Reaction as an Assay for Tannin in Sorghum Grain,” Journal of Agricultural and Food Chemistry, Vol. 26, No. 5, 1978, pp. 1214-1218. doi:10.1021/jf60219a031

[26]   B. A. K. Chibber, E. T. Mertz and J. D. Axtell, “In Vitro Digestibility of High-Tannin Sorghum at Different Stages of Dehulling,” Journal of Agricultural and Food Chemistry, Vol. 28, No. 1, 1980, pp. 160-161. doi:10.1021/jf60227a035

[27]   R. M. Saunders, M. A. Connor, R. H. Edwards and G. O. Kohler, “Enzymatic Processing of Wheat Bran: Effects on Nutrient Availability,” American Association of Cereal Chemists, Vol. 49, 1972, pp. 438-442.

[28]   S. M. Aisha Fageer, E. E. Babiker and A. H. El Tinay, “Effect of Malt Pre-Treatment and/or Cooking on Phytate and Essential Amino Acid Content and in Vitro Protein Digestibility of Corn Flour,” Food Chemistry, Vol. 88, No. 2, 2004, pp. 261-265. doi:10.1016/j.foodchem.2004.01.040

[29]   K. Vijayakumari, M. Pugalenthi and V. Vadivel, “Effect of Soaking and Hydrothermal Processing Methods on the Levels of Antinutrients and in Vitro Protein Digestibility of Bauhinia Purpurea L. Seeds,” Food Chemistry, Vol. 103, No. 3, 2007, pp. 968-975. doi:10.1016/j.foodchem.2006.07.071

[30]   U. Singh and R. Jambunathan, “Studies on Desi and Kabuli Chichpea (Cicer arietinum L) Cultivars: Levels of Protease Inhibitors, Levels of Polyphenolic Compounds and in Vitro Digestibility,” Journal of Food Science, Vol. 46, No. 5, 1981, pp. 1364-1367. doi:10.1111/j.1365-2621.1981.tb04176.x

[31]   G. Ravindran, “Seed Protein of Millets; Amino Acid Composition, Proteinase and in-Vitro Protein Digestibility,” Food Chemistry, Vol. 44, No. 1, 1992, pp. 13-17. doi:10.1016/0308-8146(92)90251-V

[32]   S. K.Sathe, V. Iyer and D. K. Salunkhe, “Functional Properties of the Great Nothern Bean (Phaseolus Vulgaris, L.) Proteins. Amino Acid Composition, in Vitro Digestibility and Application to Cookies,” Journal of Food Science, Vol. 47, No. 1, 1982, pp. 8-11. doi:10.1111/j.1365-2621.1982.tb11014.x

[33]   A. Shaturvedi and G. Sarojini, “Malting of PEARL MILLET (Pennisetum Typhoideum)—Its Effect on Starch and Protein Digestibility,” Journal of Food Science and Tech- nology, Vol. 33, No. 4, 1996, pp. 342-344.

[34]   V. J. Bhise, J. K. Chavan and S. S. Kadam, “Effects of Malting on Proximate Composition and in Vitro Protein and Starch Digestibilities of Grain Sorghum,” Association of Food Scientists and Technologists, Vol. 25, No. 6, 1988, pp. 327-329.