Rice is a staple carbohydrate throughout much of the world. Previous work indicated that resistant starch (RS) content of rice consumed in India varied with rice variety and cooking method. This study quantified RS in 4 white rice varieties (jasmine, long grain, medium grain, and short grain) cooked in three manners (oven baked, conventional rice cooker, and pressure cooker), and analyzed for RS content immediately after preparation or after 3 days of refrigeration at 4°C. The rice varieties with the highest and lowest RS content were selected for a pilot- scale trial to characterize postprandial glycemic response and appetite ratings in healthy adults (n=21). Refrigerated long-grain rice cooked in a conventional rice cooker had the highest RS content (HRS, 2.55 g RS/100 g) and refrigerated short-grain rice cooked in a pressure cooker had the lowest RS content (LRS, 0.20 g RS/100 g). These rice samples were served reheated in the clinical trial. Glucose area under the curve (AUC) were significantly lower with HRS and LRS compared to glucose beverage; however, there was no difference between HRS and LRS. Glycemic indices did not differ significantly between HRS and LRS. Subjects reported an overall increased feeling of fullness and decreased desire to eat based on incremental area under the curve (iAUC) for both HRS and LRS compared to control. This study found that RS naturally occurring in rice had minimal impact on the postprandial glycemic response and appetite.
在許多國家之中，稻米是平日飲食中澱粉攝取的主要來源。印度的研究指出， 稻米因品種及烹煮方式不同，其抗性澱粉含量有明顯的差異。本研究利用四種 不同品種的稻米(jasmine、long grain、medium grain 及short grain)，並以三種不 同的烹煮方式(烤箱、電鍋及壓力鍋)處理後，來檢測其抗性澱粉含量的變化。 米樣品分別於烹煮後立即分析其抗性澱粉含量，以及4°C 冷藏保存三天後，進 行第二次定量分析。本研究根據四種稻米經過不同烹煮方式的抗性澱粉含量結 果，選取其中最高及最低含量的米樣品做為下一階段臨床試驗，給予21 位健 康受試者食用，用以探討稻米中抗性澱粉的含量多寡是否能影響人體之餐後血 糖及食慾。在所有米樣品中，發現使用電鍋烹煮再經過冷藏處理的長米(long grain)為最高的抗性澱粉含量(HRS, 2.55 g RS/100 g)。而以壓力鍋烹煮再經過冷 藏後的圓米(short grain)為最低含量(LRS, 0.20 g RS/100 g)。因此，受試者食用 加熱過的此兩種米樣品，並於兩小時內，定時檢測餐後血糖及食慾變化。結果 顯示，HRS 及LRS 餐後血糖之曲線下面積顯著低於葡萄糖，但比較HRS 及 LRS 對於餐後血糖的影響及其昇糖指數，皆無統計上的差異。此外，對於食慾 的影響，受試者表示食用HRS 及LRS 比葡萄糖有顯著地增加飽足感，並且有 效降低多食用的慾望。綜合研究結果表示，存在此四種稻米中的天然抗性澱粉 含量，對於人體餐後血糖及食慾之影響並非十分明顯。