Glycemic Index of Selected Indian Rice Varieties

Abstract

Aims: For prevention and management of type II diabetes among rice eating population, consumption of rice with lower Glycemic Index (GI) is highly desirable as low GI food decreases plasma glucose levels and plasma insulin demand. As there is paucity of information on the GIs of commonly consumed rice varieties in India, the aim of this study was to determine GI of selected five rice varieties, and to find relationship of GI with their cooking and eating quality traits.
 Study Design, Place and Duration: In vivo experiment was conducted at PG&RC, PJTS Agricultural University, Hyderabad, India, during March, 2017 to February, 2018. During this period, cooking and eating quality traits of selected rice varieties were determined in ICAR- Indian Institute of Rice Research, Hyderabad, India.
 Methodology: GIs were determined by feeding10 fasted human subjects a fixed portion of foods and subsequently measuring plasma glucose of their blood samples at specific interval of time and GIs were calculated using standard formula. Cooking and eating quality traits were determined using standard procedure.
 Results: The estimated GI values were 56.38(SEM 1.57), 59.23(SEM 1.02), 71.73 (SEM 1.75), 87.40 (SEM 1.90), and 94.05 (SEM 1.21), respectively for Sampada, Dhanrasi, DRR Dhan 42, DRR Dhan 43, and Jarava. Alkali spreading value (ASV), Gel consistency (GC), and Water uptake (WU) values of these five varieties ranged from 4 to 6, 22 mm to 54.5 mm, and 80 ml/ 100 g to 255 ml/100 g, respectively.
 Conclusion: Two varieties were identified with moderate GI values (Sampada, 56.38 ± 1.57; Dhanrasi, 59.23± 1.02). These varieties can prove to be a healthier option to incorporate in nutritional therapeutic diet. It is also concluded that lower ASV, higher GC, and lower WU, are good predictors for lower GIs of rice varieties. These relationships may be used for screening of low GI rice cultivars in breeding programme.

Cooking quality of rice is a potential predictor to identify low starch digestibility rice

“…A similar positive association was also reported by Azam et al . (2020) where they concluded that lower WU upon cooking is a good predictor for low GI rice. The strong correlation may be explained as WU mainly involves hydrothermal processing of rice which can be held responsible for altering the effects of starch and non‐starch components on starch digestion (Khatun et al ., 2019).…”

“…Rice typically falls into the category of foods with GI ranging from 55–69 to >70. Foods low in GI (<55) slow down the pace at which starch is hydrolyzed, thus helping in decreasing levels of plasma glucose, insulin response and plasma insulin demand (Azam et al ., 2020).…”

“…The amylose content is considered as most important factor among ECQs as it is directly related to water absorption and affects grain texture and organoleptic qualities. Apart from AC, other ECQs parameters associated with starch physical and chemical characteristics like Gel consistency (GC), Alkali spreading value (ASV) and water uptake (WU) are considered vital intrinsic quality components which take a lead role in deciding starch digestibility of rice (Panlasigui et al ., 1991; Azam et al ., 2020).…”

Effect of processing on resistant starch content of Indian rice varieties (Sona Masuri and Mogra) and its impact on postprandial blood glucose levels

“…GI was calculated by using IAUC. (Azam et al, 2020). Variation caused in RS due to the proportion of amylose to amylopectin in grains may decrease total GI in foods after cooking.…”