The knowledge of solid loss kinetics of foods during digestion is crucial for understanding the factors that constrain the release of nutrients from the food matrix and their fate of digestion. The objective of this study was to investigate the solid loss of carrots during simulated gastric digestion as affected by pH, temperature, viscosity of gastric fluids, mechanical force present in stomach, and cooking. Cylindrical carrot samples were tested by static soaking method and using a model stomach system. The weight retention, moisture, and loss of dry mass were determined. The results indicated that acid hydrolysis is critical for an efficient mass transfer and carrot digestion. Internal resistance rather than external resistance is dominant in the transfer of soluble solids from carrot to gastric fluid. Increase in viscosity of gastric fluid by adding 0.5% gum (w/w) significantly increased the external resistance and decreased mass transfer rate of carrots in static soaking. When mechanical force was not present, 61% of the solids in the raw carrot samples were released into gastric fluid after 4 h of static soaking in simulated gastric juice. Mechanical force significantly increased solid loss by causing surface erosion. Boiling increased the disintegration of carrot during digestion that may favor the loss of solids meanwhile reducing the amount of solids available for loss in gastric juice. Weibull function was successfully used to describe the solid loss of carrot during simulated digestion. The effective diffusion coefficients of solids were calculated using the Fick’s second law of diffusion for an infinite cylinder, which are between 0.75 × 10⁻¹¹ and 8.72 × 10⁻¹¹ m²/s, depending on the pH of the gastric fluid.

中文翻译：

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模拟胃消化过程中胡萝卜的固体损失。

食物在消化过程中的固体损失动力学知识对于了解限制营养物质从食物基质中释放的因素及其消化命运至关重要。本研究的目的是研究模拟胃消化过程中胡萝卜的固体损失，其受 pH 值、温度、胃液粘度、胃中存在的机械力和烹饪的影响。通过静态浸泡方法和使用模型胃系统测试圆柱形胡萝卜样品。测定重量保留、水分和干重损失。结果表明酸水解对于有效的传质和胡萝卜消化至关重要。在可溶性固体从胡萝卜转移到胃液中，内部阻力而不是外部阻力占主导地位。w / w ) 显着增加了胡萝卜在静态浸泡中的外部阻力并降低了传质速率。当不存在机械力时，在模拟胃液中静态浸泡 4 小时后，生胡萝卜样品中 61% 的固体释放到胃液中。机械力通过引起表面侵蚀显着增加了固体损失。煮沸增加了胡萝卜在消化过程中的分解，这可能有利于固体的损失，同时减少了胃液中可用于损失的固体量。Weibull 函数成功地用于描述模拟消化过程中胡萝卜的固体损失。固体的有效扩散系数是使用菲克第二扩散定律计算的无限圆柱体，在 0.75 × 10^-11和 8.72 × 10 ^-11  m ² /s，取决于胃液的 pH 值。