The present study aims to evaluate the effect of polishing on the quality attributes of the indigenous rice varieties of Assam namely Aghuni bora and Kajoli chakua. In the study procured paddy varieties were processed using standard protocols into unpolished, 5% polished and 10% polished forms. Standard analytical procedures were followed to evaluate the physical, chemical and sensory quality of the rice samples. Cooking characteristics of the rice varieties were also evaluated in terms of their water uptake ratio, grain elongation ratio and cooking time. Data obtained were analysed statistically to determine significant differences (p<0.05). The findings revealed a progressive reduction in kernel dimensions and mass. The Thousand kernel weight decreased from 19.62 to 15.64 g in Aghuni bora and from 20.68 to 15.22 g in Kajoli chakua. The Bulk density of the samples increased from 0.63 to 1.29 g ml-1 in Aghuni bora and from 0.71 to 1.36 g ml-1 in Kajoli chakua across polishing. The lightness value showed an increasing trend from 65.99 to 72.78 in Aghuni bora and from 65.40 to 69.81 in Kajoli chakua, while a* and b* values decreased, indicating a loss of natural pigmentation. An improvement in cooking quality in terms of water uptake ratio and a decrease in cooking time was evident from 16.00 to 10.12 min in Aghuni bora and from 17.33 to 9.80 min in Kajoli chakua. A significant reduction in protein, fat, crude fibre, ash and mineral contents with increased polishing were also observed. The study concludes that with milling up to 5.00%, an optimal balance could be achieved between nutritional retention, cooking efficiency, sensory acceptability and reduced processing losses.
Tiwari, M., Bordoloi, P.L., Barooah, M.S., 2026. Effect of milling on quality attributes and nutritional security of indigenous rice varieties of Assam. Research Biotica 8(2), 49-57. DOI: 10.54083/ResBio/8.2.2026/49-57.
Cooking quality, Degree of milling, Indigenous rice varieties, Physico-chemical properties, Sensory quality
Achary, V.M.M., Reddy, M.K., 2021. CRISPR-Cas9 mediated mutation in GRAIN WIDTH and WEIGHT2 (GW2) locus improves aleurone layer and grain nutritional quality in rice. Scientific Reports 11(1), 21941. DOI: https://doi.org/10.1038/s41598-021-00828-z
Akhter, K.T., Shozib, H.B., Islam, M.H., Sarwar, S., Islam, M.M., Akanda, M.R., Siddiquee, M.A., Mohiduzzaman, M., Rahim, A.T.M.A., Shaheen, N., 2023. Variations in the major nutrient composition of dominant high-yield varieties (HYVs) in parboiled and polished rice of Bangladesh. Foods 12(21), 3997. DOI: https://doi.org/10.3390/foods12213997
Akter, S., Begum, R., Dipti, S.S., Alim, M.A., Shuchy, S.I., Shozib, H.B., Hasan, M.R., 2025. Effect of Degree of Milling (DOM) on physicochemical and nutritional quality of selected rice variety (BRRI Dhan78). International Journal of Food Science 2025(1), 6034633. DOI: https://doi.org/10.1155/ijfo/6034633
Antonini, E., Zara, C., Valentini, L., Gobbi, P., Ninfali, P., Menotta, M., 2018. Novel insights into pericarp, protein body globoids of aleurone layer, starchy granules of three cereals gained using atomic force microscopy and environmental scanning electronic microscopy. European Journal of Histochemistry 62(1), 2869. DOI: https://doi.org/10.4081/ejh.2018.2869
AOAC, 2005. Official Methods of Analysis, 18th Edition. Association of Official Analytical Chemists (AOAC) International, Maryland, USA.
Bani, C., Cappa, C., Restani, P., Sala, M., Colombo, F., Mercogliano, F., Di Lorenzo, C., 2024. Physicochemical and nutritional quality of pigmented rice and bran: Influence of milling and cooking. LWT 208, 116653. DOI: https://doi.org/10.1016/j.lwt.2024.116653
Bhattacharya, K.R., 2011. Rice Quality: A Guide to Rice Properties and Analysis. Woodhead Publishing, London. pp. 61-99.
Bualuang, O., Tirawanichakul, S., Tirawanichakul, Y., 2011. Study of drying kinetics and qualities of two parboiled rice: Hot air and infrared radiation. In: Proceedings of the TIChE International Conference. pp. 1-6.
Chatterjee, L., Das, P., 2019. Chemical properties of six indigenous rice varieties of Assam. International Journal of Chemical Studies 7(1), 2515-2519.
Chen, B., Qiao, Y., Wang, X., Zhang, Y., Fu, L., 2023. Extraction, structural characterization, biological functions and application of rice bran polysaccharides: A review. Foods 12(3), 639. DOI: https://doi.org/10.3390/foods12030639
Deepa, G., Singh, V., Naidu, K.A., 2008. Nutrient composition and physicochemical properties of Indian medicinal rice - Njavara. Food Chemistry 106(1), 165-171.
Donmez, D., Pinho, L., Patel, B., Desam, P., Campanella, O.H., 2021. Characterization of starch-water interactions and their effects on two key functional properties: Starch gelatinization and retrogradation. Current Opinion in Food Science 39, 103-109. DOI: https://doi.org/10.1016/j.cofs.2020.12.018
Du, Z., Jia, Y., Hu, P., Xu, H., Jiao, G., Tang, S., 2025. The impact of OsERF34 on rice grain-processing traits and appearance quality. Plants 14(11), 1633. DOI: https://doi.org/10.3390/plants14111633
Elancheran, E., Anupama, B.S., Sumalatha, N., Sakhare, S.D., 2026. Degree of milling on proso millet: Exploring the impact on engineering, physicochemical, thermal and microstructural properties of fractions. Journal of Food Process Engineering 49(4), e70462. DOI: https://doi.org/10.1111/jfpe.70462
Ficiciyan, A., Loos, J., Sievers-Glotzbach, S., Tscharntke, T., 2018. More than yield: Ecosystem services of traditional versus modern crop varieties revisited. Sustainability 10(8), 2834. DOI: https://doi.org/10.3390/su10082834
Fraser, B.M., Verma, S.S., Muir, W.E., 1978. Some physical properties of fababeans. Journal of Agricultural Engineering Research 23(1), 53-57. DOI: https://doi.org/10.1016/0021-8634(78)90079-3
Gondal, T.A., Keast, R.S.J., Shellie, R.A., Jadhav, S.R., Gamlath, S., Mohebbi, M., Liem, D.G., 2021. Consumer acceptance of brown and white rice varieties. Foods 10(8), 1950. DOI: https://doi.org/10.3390/foods10081950
Gujral, H.S., Singh, J., Sodhi, N.S., Singh, N., 2002. Effect of milling variables on the degree of milling of unparboiled and parboiled rice. International Journal of Food Properties 5(1), 193-204. DOI: https://doi.org/10.1081/JFP-120015601
Handoko, D.D., Mardiah, Z., Septianingrum, E., Indrasari, S.D., 2021. Physicochemical properties of some improved Indonesian red rice flour varieties. IOP Conference Series: Earth and Environmental Science 828(1), 012023. DOI: https://doi.org/10.1088/1755-1315/828/1/012023
Harlan, J.R., 1975. Geographic patterns of variation in some cultivated plants. Journal of Heredity 66(4), 182-191. DOI: https://doi.org/10.1093/oxfordjournals.jhered.a108610
Iwai, T., Takahashi, M., Oda, K., Terada, Y., Yoshida, K.T., 2012. Dynamic changes in the distribution of minerals in relation to phytic acid accumulation during rice seed development. Plant Physiology 160(4), 2007-2014. DOI: https://doi.org/10.1104/pp.112.206573
James, C.S., 1995. Analytical Chemistry of Foods, 19th Edition. Blackie Academic & Professional, London.
Juliano, B.O., 1971. A simplified assay for milled-rice amylose. Cereal Science Today 16(10), 334-340.
Juliano, B.O., Bechtel, D.B., 1985. The rice grain and its gross composition. In: Rice: Chemistry and Technology, 2nd Edition, Volume 2. (Ed.) Juliano, B.O. American Association of Cereal Chemists (AACC), St. Paul, MN. pp. 17-57.
Kalita, T., Hazarika, J., 2022. Morphological study, nutritional value and phytochemical estimation of four indigenous rice (Oryza sativa L.) varieties of Assam, India. Food Research 6(1), 196-203. DOI: https://doi.org/10.26656/fr.2017.6(1).080
Lamberts, L., De Bie, E., Vandeputte, G.E., Veraverbeke, W.S., Derycke, V., De Man, W., Delcour, J.A., 2007. Effect of milling on colour and nutritional properties of rice. Food Chemistry 100(4), 1496-1503. DOI: https://doi.org/10.1016/j.foodchem.2005.11.042
Leardkamolkarn, V., Thongthep, W., Suttiarporn, P., Kongkachuichai, R., Wongpornchai, S., Wanavijitr, A., 2011. Chemopreventive properties of the bran extracted from a newly-developed Thai rice: The Riceberry. Food Chemistry 125(3), 978-985. DOI: https://doi.org/10.1016/j.foodchem.2010.09.093
Li, H., Yan, S., Yang, L., Xu, M., Ji, J., Mao, H., Song, Y., Wang, J., Sun, B., 2021. Starch gelatinization in the surface layer of rice grains is crucial in reducing the stickiness of parboiled rice. Food Chemistry 341, 128202. DOI: https://doi.org/10.1016/j.foodchem.2020.128202
Li, J., Yang, S., Zhong, Z., Xia, T., Zhou, W., Tu, Z., Chen, Z., Wang, H., Dai, Z., Jin, G., Du, Y., 2025. Effects of degree of milling on bran layer structure, physicochemical properties and cooking quality of brown rice. Food Chemistry 462, 140847. DOI: https://doi.org/10.1016/j.foodchem.2024.140847
Mackill, D.J., Khush, G.S., 2018. IR64: A high-quality and high-yielding mega variety. Rice 11(1), 18. DOI: https://doi.org/10.1186/s12284-018-0208-3
Mohapatra, D., Bal, S., 2014. Rice colour measurement for various milling fractions. Journal of Grain Processing and Storage 1(1), 28-33.
Monks, J.L.F., Vanier, N.L., Casaril, J., Berto, R.M., de Oliveira, M., Gomes, C.B., de Carvalho, M.P., Dias, A.R.G., Elias, M.C., 2013. Effects of milling on proximate composition, folic acid, fatty acids and technological properties of rice. Journal of Food Composition and Analysis 30(2), 73-79. DOI: https://doi.org/10.1016/j.jfca.2013.01.009
Mudoi, T., Das, P., 2019. A study on phytochemicals and mineral content of indigenous red rice of Assam, India. International Journal of Current Microbiology and Applied Sciences 8(4), 1-12. DOI: https://doi.org/10.20546/ijcmas.2019.804.001
Nádvorníková, M., Banout, J., Herák, D., Verner, V., 2018. Evaluation of physical properties of rice used in traditional Kyrgyz cuisine. Food Science and Nutrition 6(6), 1778-1787. DOI: https://doi.org/10.1002/fsn3.746
Nitisewojo, P., 1995. Prinsip analisis makanan, 2nd Edition. Penerbit Universiti Kebangsaan, Bangi, Malaysia. p. 101.
Ojediran, J.O., Okonkwo, C.E., Olayanju, T.A., Hussain, S.Z., Olaniran, A.F., Adewumi, A.D., 2020. Effect of polishing duration on physical, milling, cooking and sensory properties of a novel mix‐colored Nigerian parboiled rice. Cereal Chemistry 97(6), 1172-1182. DOI: https://doi.org/10.1002/cche.10337
Olayanju, A.T., Okonkwo, C.E., Ojediran, J.O., Hussain, S.Z., Dottie, E.P., Ayoola, A.S., 2021. Interactive effects and modeling of some processing parameters on milling, cooking and sensory properties for Nigerian rice using a one-step rice milling machine. Heliyon 7(4), e06739. DOI: https://doi.org/10.1016/j.heliyon.2021.e06739
Ponnappan, S., Thangavel, A., Sahu, O., 2017. Milling and physical characteristics of pigmented rice varieties. International Journal of Food Chemistry 1(1), 24-29. DOI: https://doi.org/10.11648/j.ijfc.20170101.15
Qadir, N., Wani, I.A., 2023. Physical properties of four rice cultivars grown in Indian temperate region. Applied Food Research 3(1), 100280. DOI: https://doi.org/10.1016/j.afres.2023.100280
Rahmawati, R., Pujilestari, S., Amelia, J.R., 2023. Physical characteristics of local light-brown waxy sorghum with varying levels of polishing. Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) 12(3), 632-640. DOI: https://doi.org/10.23960/jtep-l.v12i3.632-640
Ravindra Babu, V.R., Shreya, K., Dangi, K.S., Usharani, G., Nagesh, P., 2013. Evaluation of popular rice (Oryza sativa L.) hybrids for quantitative, qualitative and nutritional aspects. International Journal of Scientific and Research Publications 3(1), 2250-3153.
Razavi, S.M.A., Farahmandfar, R., 2008. Effect of hulling and milling on the physical properties of rice grains. International Agrophysics 22(4), 353-359.
Reddy, C.K., Kimi, L., Haripriya, S., Kang, N., 2017. Effects of polishing on proximate composition, physico-chemical characteristics, mineral composition and antioxidant properties of pigmented rice. Rice Science 24(5), 241-252. DOI: https://doi.org/10.1016/j.rsci.2017.05.002
Sandhu, R.S., Singh, N., Kaler, R.S.S., Kaur, A., Shevkani, K., 2018. Effect of degree of milling on physicochemical, structural, pasting and cooking properties of short and long grain indica rice cultivars. Food Chemistry 260, 231-238. DOI: https://doi.org/10.1016/j.foodchem.2018.03.092
Singh, N., Sodhi, N.S., Kaur, M., Saxena, S.K., 2003. Physico-chemical, morphological, thermal, cooking and textural properties of chalky and translucent rice kernels. Food Chemistry 82(3), 433-439. DOI: https://doi.org/10.1016/S0308-8146(03)00007-4
Sow, S., Ranjan, S., 2021. A review on agronomic biofortification for improving food and nutritional security. Research Biotica 3(2), 139-144. DOI: https://doi.org/10.54083/ResBio/3.2.2021.139-144
Subedi, U., Karki, R., Ojha, P., Mishra, A., Shrestha, M.B., Dongol, D.M.S., 2018. Degree of milling effect on cold water rice quality. Journal of Nepal Agricultural Research Council 4(1), 7-17. DOI: https://doi.org/10.3126/jnarc.v4i1.19685
Thomas, R., Wan-Nadiah, W.A., Bhat, R., 2013. Physicochemical properties, proximate composition and cooking qualities of locally grown and imported rice varieties marketed in Penang, Malaysia. International Food Research Journal 20(3), 1345-1351.
Thongbam, P.D., Raychaudhury, M., Durai, A., Das, S.P., Ramesh, T., Ramya, K.T., Ngachan, S.V., 2012. Studies on grain and food quality traits of some indigenous rice cultivars of North-Eastern Hill Region of India. Journal of Agricultural Science 4(3), 259-268. DOI: https://doi.org/10.5539/jas.v4n3p259
Tiwari, A., Kesarwani, K., Ghosh, T., Rai, S., 2020. Declining nutrients from our plates. Research Biotica 2(4), 135-140. DOI: https://doi.org/10.54083/ResBio/2.4.2020.135-140
Tumanian, N.G., Papulova, E.Y., Chizhikova, S.S., Kumeiko, T.B., 2021. Impact of degree of polishing on technological and biochemical grain quality traits of rice varieties of Russian breeding. IOP Conference Series: Earth and Environmental Science 624(1), 012177. DOI: https://doi.org/10.1088/1755-1315/624/1/012177
Wang, L., Wang, M., Lv, R., Guo, M., Ye, X., Ding, T., Liu, D., 2019. Modelling the physical properties change of canned glutinous rice porridge during cooking. RSC Advances 9(10), 5521-5529. DOI: https://doi.org/10.1039/c8ra07790h
Wiset, L., Srzednicki, G., Driscoll, R.H., Nimmuntavin, C., Siwapornrak, P., 2001. Effects of high temperature drying on rice quality. Agricultural Engineering International: The CIGR Journal of Scientific Research and Development 3(1), 1-10.
Yang, L., Luo, Y., Xiao, X., Li, Y., Zhao, J., Pei, H., Song, S., Zhang, Y., 2023. Research on rice grain damage behavior with experimental and finite element modeling. Journal of Food Process Engineering 46(8), e14369. DOI: https://doi.org/10.1111/jfpe.14369
Yildirim, A., 2021. Moisture diffusivity, hardness, gelatinization temperature and thermodynamic properties of ultrasound assisted soaking process of cowpea. Journal of Food Process Engineering 44(11), e13863. DOI: https://doi.org/10.1111/jfpe.13863
Yu, X.R., Zhou, L., Xiong, F., Wang, Z., 2014. Structural and histochemical characterization of developing rice caryopsis. Rice Science 21(3), 142-149. DOI: https://doi.org/10.1016/S1672-6308(13)60176-6
Zaupa, M., Calani, L., Del Rio, D., Brighenti, F., Pellegrini, N., 2015. Characterization of total antioxidant capacity and (poly)phenolic compounds of differently pigmented rice varieties and their changes during domestic cooking. Food Chemistry 187, 338-347. DOI: https://doi.org/10.1016/j.foodchem.2015.04.055
Zhang, Y., Li, F., Huang, K., Li, S., Cao, H., Xie, J., Guan, X., 2023. Structural changes of starch under different milling degrees affect the cooking and textural properties of rice. Food Chemistry: X 17, 100627. DOI: https://doi.org/10.1016/j.fochx.2023.100627
Zhu, S.M., Hu, F.F., Ramaswamy, H.S., Yu, Y., Yu, L., Zhang, Q.T., 2016. Effect of high pressure treatment and degree of milling on gelatinization and structural properties of brown rice. Food and Bioprocess Technology 9(11), 1844-1853. DOI: https://doi.org/10.1007/s11947-016-1770-6
