Helbig Elizabete, Días Alvaro Renato Guerra, Tavares Rafael Aldrighi, Schirmer Manoel Artigas, Elias Moacir Cardoso
Universidade Federal de Pelotas - Departamento de Ciência e Tecnologia Agroindustrial. Pelotas, RS, Brasil.
Arch Latinoam Nutr. 2008 Jun;58(2):149-55.
Starch is an important energy source and can represent more than 60% of the calories of the human diet. The starch fraction resistant to enzymatic digestion is called resistant starch. When rice is parboiled, the starch retrogrades with the formation of type 3-resistant starch (retrograded), which presents beneficial effects on the health, since it acts as a prebiotic. In the present study three types of rice were selected, with high, medium and low amylose contents, with the objective of evaluating the effects of conventional and parboiled rice on glycemia in Wistar rats. The samples with high and medium amylose contents were soaked for 6 h at 65 degrees C, and the low amylose sample for 7 h at 70 degrees C. The samples were subsequently autoclaved for 10 minutes at 0.7kgf x cm(-2). Six male Wistar rats were used for each treatment. Seven experimental diets were elaborated, formulated according to AIN-93M, the control diet and diets substituting the carbohydrate source with conventional or parboiled rice. Resistant starch was determined in the diets and glycemia monitored using glucose paper strips, the sample being blood obtained from the distal part of the rat's tail. For the glycemic curve, glycemia was measured in the fasting state and during 90 minutes post-prandial. The results indicated there were no significant differences between the diets formulated with high, medium and low amylose, parboiled or conventionally prepared, with respect to fasting or post-prandial glycemia in Wistar rats.
淀粉是一种重要的能量来源,在人类饮食热量中所占比例可超过60%。抗酶消化的淀粉部分称为抗性淀粉。大米进行预煮时,淀粉会发生回生,形成3型抗性淀粉(回生淀粉),它对健康具有有益作用,因为其可作为益生元。在本研究中,选取了直链淀粉含量高、中、低的三种大米,目的是评估常规大米和预煮大米对Wistar大鼠血糖的影响。直链淀粉含量高和中等的样品在65℃下浸泡6小时,直链淀粉含量低的样品在70℃下浸泡7小时。随后将样品在0.7kgf x cm(-2)压力下高压灭菌10分钟。每种处理使用6只雄性Wistar大鼠。根据AIN-93M精心配制了七种实验日粮,即对照日粮以及用常规大米或预煮大米替代碳水化合物来源的日粮。测定日粮中的抗性淀粉,并使用葡萄糖试纸监测血糖,样品为从大鼠尾巴远端采集的血液。对于血糖曲线,在空腹状态和餐后90分钟内测量血糖。结果表明,就Wistar大鼠的空腹或餐后血糖而言,用直链淀粉含量高、中、低的大米配制的预煮或常规制备的日粮之间没有显著差异。