Effect of cooking on glycemic index, antioxidant activities, α‐amylase, and α‐glucosidase inhibitory properties of two rice varieties

Abstract

This study was designed to investigate the influence of cooking on the glycemic index (GI), amylose, and amylopectin contents of two rice varieties. Two rice varieties (foreign long rice and ofada) were sourced for, divided into two, one portion cooked and the other used raw. The sugar, starch, amylose, and amylopectin contents as well as glycemic indices, antioxidant properties, and the ability of the rice to inhibit carbohydrate‐hydrolyzing enzymes (α‐amylase and α‐glucosidase) were determined. In addition, polyphenol content was determined. The results revealed that cooking caused a significant increase in starch content of the rice varieties. In the same vein, cooking increases the amylopectin content but has no effect on the amylose content. In addition, cooking shows no effect on polyphenol content but significantly increases radical scavenging ability of rice varieties used in this study. Furthermore, cooking lower the α‐amylase and α‐glucosidase inhibitory properties of two rice varieties except for foreign rice. However, the inhibitory effect of both cooked and raw foreign and ofada rice on α‐amylase and α‐glucosidase coupled with their low GI may explain their important role in controlling blood glucose level.

Evaluation of Various Starchy Foods: A Systematic Review and Meta-Analysis on Chemical Properties Affecting the Glycemic Index Values Based on In Vitro and In Vivo Experiments

“…In total, the meta-analysis involved fifty-seven articles, as exhibited in Figure 1 . According to the Cochrane Collaboration tool, eleven trials [ 6 , 24 , 29 , 32 , 33 , 37 , 38 , 42 , 48 , 51 , 54 ] were categorized as being at a low risk of bias, while forty-four were categorized as unclear [ 17 , 19 , 20 , 21 , 22 , 23 , 25 , 27 , 28 , 30 , 31 , 34 , 35 , 36 , 39 , 40 , 41 , 43 , 44 , 45 , 46 , 47 , 49 , 50 , 52 , 53 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 ], and two were categorized as being at a high risk of bias [ 18 , 26 ]. Details about the risk of bias are supplied in Figure 2 and Figure 3 .…”

“…Fifty-seven studies, involving 936 participants, were published from 2002 to 2019. Twenty-six studies [ 9 , 10 , 11 , 12 , 17 , 18 , 20 , 21 , 26 , 31 , 35 , 39 , 43 , 44 , 45 , 46 , 47 , 49 , 54 , 55 , 56 , 57 , 59 , 60 , 61 , 62 ] used an in vitro experiment, while thirty-two studies involved in vivo experiments. Only one study used both in vitro and in vivo data experiments [ 11 ].…”

“…The study design used in this research was the completely randomized design. Among fifty-seven included studies, forty-eight were selected for discussion of the relationship between chemical properties and GI value [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 ]. The remaining studies were used for the selection of low-GI carbohydrate-based foods [ 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 ].…”

Antioxidant activities and glycemic indices of ice creams enriched with orange ( Citrus sinensis ) and shaddock ( Citrus maxima ) peels and effects on rat lipid profiles

“…The GI of 25 mg of samples uses 5‐ml stomach solution (KCl–HCl buffer pH 1.5), 2.5‐ml α‐amylase solution, 500‐µl sodium acetate pH 4.75, 5 µl of α‐glucosidase solution, DNSA solution (200 µl) and reads at an absorbance of 540 nm according to the method of Adedayo et al (2018). The sum of area under curve for each sample was divided by the sum of area under curve for standard glucose and multiplied by 100.…”

Effects of Different Processing Methods and Internal Components on Physicochemical Properties and Glycemic Index of Adzuki Bean Powder

“…The structure and digestibility of starchy food can be affected by different processing methods, such as milling (i.e., wet and dry milling) and cooking (e.g., steaming, extrusion), and could further influence the glycemic response [8][9][10]. The use of different milling methods could result in a different content of damaged starch.…”