Effect of cooking and storage temperature on resistant starch in commonly consumed Indian wheat products and its effect upon blood glucose level

• Published in: Frontiers in nutrition (Lausanne) 2023-11, Vol.10, p.1284487-1284487
• Main Authors: Kaur, Prabhjot, Kaur, Harpreet, Aggarwal, Renuka, Bains, Kiran, Mahal, Amrit Kaur, Gupta, O P, Singla, Lachhman Das, Singh, Kulvinder
• Format: Article
• Language: English
• Subjects: amylopectin; amylose; dietary fibre; glycemic index; Nutrition; resistant starch; wheat products
• ISSN: 2296-861X; 2296-861X
• DOI: 10.3389/fnut.2023.1284487

The health benefits provided by resistant starch have been well documented; however, few studies are available on the resistant starch content of wheat products in India. Moreover, few studies have examined the efficacy of resistant starch in wheat products in improving glucose levels. This study was conducted to evaluate the effect of cooking and storage temperature on the formation of resistant starch in Indian wheat products and its effect on blood glucose levels in humans and rats. Wheat products were prepared by common cooking methods including roasting ( ), boiling ( ), Shallow frying ( ), and Deep frying ( ). They were then stored at different temperatures including freshly prepared within 1 h (T1), stored for 24 h at room temperature (20-22°C) (T2), kept at 4°C for 24 h (T3) and reheated after storing at 4°C for 24 h (T4). The products were then analyzed for proximate composition (moisture, crude protein, crude fat, ash crude fibre, and carbohydrates). The effect of different cooking methods and storage temperatures on Resistant, non-resistant and total starch, total dietary fibre (soluble and insoluble), starch digestion rate (rapidly and slowly digestible starch), amylose and amylopectin content were analysed using standard operating procedures. The effect of products found to have higher resistant starch was studied on the post prandial blood glucose response of 10 healthy individuals using change in by analysing their glycemic index and glycemic load of wheat products. Further, the effect of resistant starch rich on the blood glucose level of rats was also studied. Tukey's test in factorial CRD was used to assess the effect of cooking and temperature on various parameters. The amount of resistant starch was found to be high in (boiling, 7.74%), followed by (shallow frying, 4.94%), (roasting, 2.77%) and (deep frying 2.47%). Under different storage temperatures, it was found high in products stored at 4°C (T3), followed by products stored at room temperature (T2), reheated products (T4) and lesser in freshly prepared products (T1). The glycemic index and glycemic load were found low in (43, 32.3) and (41.1, 28.6) stored at 4°C (T3) compared to others. The resistant starch content found in stored at T3 was found to be more effective at reducing blood glucose levels in rats from 291.0 mg/100 mL to 225.2 mg/100 mL in 28 days of study compared to freshly prepared (T1) and stored at room temperature (T2). Cooking methods including boiling, roasting an