Department of Biological and Agricultural Engineering, University of California Davis, Davis, CA 95616-5294, USA.
J Sci Food Agric. 2013 Sep;93(12):2900-8. doi: 10.1002/jsfa.6160. Epub 2013 May 8.
Rice structure is important to rice grain and starch breakdown during digestion. The objective of this study was to determine the gastric emptying and rice composition during gastric digestion of cooked brown and white medium-grain (Calrose variety) rice using the growing pig as a model for the adult human.
Brown and white rice did not show significantly different gastric emptying rates of dry matter or starch, but brown rice had slower protein emptying (P < 0.05). Moisture content was greater and pH was lower in the distal stomach compared to the proximal stomach (P < 0.0001), and varied with time (P < 0.0001). The mechanism of physical breakdown for brown and white rice varied. Brown rice exhibited an accumulation of bran layer fragments in the distal stomach, quantified by lower starch and higher protein content.
The quantity of gastric secretions observed after a brown or white rice meal may be related to the meal buffering capacity, and are accumulated in the distal stomach. The delayed rate of protein emptying in brown rice compared to white rice was most likely due to the accumulation of bran layers in the stomach.
稻米结构对于稻米在消化过程中的颗粒和淀粉分解很重要。本研究的目的是利用生长猪作为成年人类模型，确定煮熟的棕色和白色中粒（Calrose 品种）稻米在胃消化过程中的胃排空和稻米成分。
棕色和白色稻米的干物质或淀粉胃排空率没有显著差异，但棕色稻米的蛋白质排空速度较慢（P<0.05）。与近端胃相比，远端胃的水分含量更高，pH 值更低（P<0.0001），且随时间变化（P<0.0001）。棕色和白色稻米的物理破碎机制不同。棕色稻米在远端胃中出现糠层碎片的积累，表现为淀粉含量降低和蛋白质含量升高。
进食棕色或白色稻米后观察到的胃分泌物的量可能与膳食缓冲能力有关，并在远端胃中积累。与白色稻米相比，棕色稻米中蛋白质排空速度较慢，这很可能是由于胃中糠层的积累。
