Previously, we have prepared a version of the dynamic in vitro rat stomach system (DIVRS-II or Biomimic Rat II). It was constructed and tested by showing similar digestive behaviors with those occurred in vivo. In the present work, a 3D-printed plastic mold was employed to create highly repeatable silicone rat stomach model. It has been seen to have shortened the time to handcraft a model like that used in DIVRS-II. The maximum mechanical force of the current stomach model generated by rolling extrusion is found to be more stable probably due to the more uniform wall thickness of the new model. Then the effects of the simulated gastric secretion patterns and contraction frequency of the system on the in vitro digestibility of casein powder suspensions were investigated. The results have shown that the location of the gastric secretion injection has an impact on experimental digestibility. The position of rolling-extrusion area, established at the central part of glandular portion (stomach B), displayed the highest digestibility compared to that at the other locations. Furthermore, the extent of digestion was positively correlated with the contraction frequency of the model stomach system, with the maximum frequency of 12 cpm giving the highest digestibility. This highest digestibility is almost the same as the average value found in vivo. The better digestive performance produced by optimizing the gastric secretion pattern and contraction frequency may be both resulted from the improved mixing efficiency of the food matrix with digestive juice. This study shows that it is possible to achieve what in vivo in a simulated digestion device, which may be used for future food and nutrition studies in vitro.

以前，我们已经准备了动态体外大鼠胃部系统的版本（DIVRS-II或Biomimic Rat II）。它的消化和消化行为与体内相似，从而进行了构造和测试。在当前的工作中，使用3D打印的塑料模具来创建高度可重复的硅胶大鼠胃模型。人们已经看到，缩短了手工制作类似于DIVRS-II中所用模型的时间。发现通过滚动挤压产生的当前胃模型的最大机械力更加稳定，这可能是由于新模型的壁厚更均匀。然后模拟的胃分泌模式和系统的收缩频率对体外的影响研究了酪蛋白粉末悬浮液的消化率。结果表明，胃分泌物注射的位置对实验消化率有影响。与其他部位相比，位于腺体中央部位（胃B）的滚动挤压部位的消化率最高。此外，消化程度与模型胃系统的收缩频率呈正相关，最大频率为12 cpm可提供最高的消化率。最高的消化率几乎与体内的平均值相同。通过优化胃液分泌方式和收缩频率而产生的更好的消化性能，可能都归因于食物基质与消化液混合效率的提高。这项研究表明，有可能在模拟消化设备中实现体内目标，该设备可用于未来的体外食品和营养研究。