Aim: Diets, which produce a low glycaemic response, are relevant to prevention and management of obesity and diabetes. The aim was to investigate the effect of rice products and cooking-storing methods on postprandial blood glucose and the changes in satiety and palatability.
Methods: The randomised, cross-over experimental trial investigated the glycaemic responses, satiety and palatability (Visualised Analogue Scale (VAS)) scores of 28 healthy participants after consumed three rice samples (140g±0.3g), freshly cooked medium-grain-white, freshly cooked parboiled, and reheated parboiled (24-hour storage at 4 ºC and reheated to 65 ºC), in each study visit. Postprandial blood glucose was recorded at 0, 15, 30, 45, 60, 90 and 120 minutes after rice consumption. Satiety (VAS score) was reported at 0, 30, 60, 90, and 120 minutes. Palatability (VAS score) was reported immediately after consumption. Glycaemic responses, satiety, and palatability among three rice samples were compared using repeated-measure-analysis of variance (ANOVA).
Results: The overnight cold-stored and reheated parboiled rice resulted in a significantly lower blood glucose concentration trajectory (42%, P=0.01) than freshly cooked medium-grain white rice and 12% lower (P=0.01) than freshly cooked parboiled rice. Longer chewing time (6.34 seconds/10 g) was observed in reheated parboiled rice compared with freshly cooked medium-grain white (P=0.026) and higher palatability (visual appeal 2-fold higher (P=0.001), smell 1-fold higher (P=0.047), taste 1.5-fold higher (P=0.018), and overall palatability 2-folder higher (P=0.002)). No significant differences in satiety were observed (P>0.05).
Conclusion: The effect of reheating on the glycaemic response, chewing time and palatability shown in the present study may be considered a positive effect with regard to glycaemic regulation. Reheated parboiled rice replacing freshly cooked medium-grain white or parboiled rice in the habitual diet may reduce glycaemic overload in the daily diet.
There is no conflict of interest in this study.