Luminescence spectroscopy coupled with molecular rotors was used in the TNO Intestinal Model-1 (TIM-1) to monitor in situ changes to luminal viscosity of three maize starch samples varying in the amylose-to-amylopectin ratio (AM: AP): normal, high amylose (AM) and high amylopectin (AP). The fluorescence intensity (FI) of Fast Green (FG), a proven micro (and bulk) viscosity probe, was monitored throughout digestion to track changes in the gastric viscosity. The FI of FG and the viscosity imparted by the starch followed a power-law relationship. The emission of the MR was unaffected by the composition of TIM-1 secretion fluids nor pH. Hence, direct measurements of digesta FI are sensitive to changing viscosity during the simulated digestion. The viscosity was highest for AP, followed by normal starch, and high AM had the lowest viscosity. In the TIM-1 gastric compartment, from highest to lowest FI, and thus viscosity was high AM > high AP > normal maize starches. We conclude the validity of the proposed method to facilitate the measurement of luminal viscosity, in vitro, when the microviscosity represents bulk viscosity (i.e., when the increase in bulk viscosity is a result of molecular crowding and the surrounding environment around the rotor is homogeneous). Careful consideration is required when foods are heterogeneous as molecular rotors report only on their local non-uniform environment.

在TNO肠模型1（TIM-1）中使用了结合分子转子的发光光谱技术来监测三个玉米淀粉样品的直链淀粉与支链淀粉比例（AM：AP）：正常，高直链淀粉（AM）和高支链淀粉（AP）。快速绿色（FG）是一种经过验证的微量（和整体）粘度探针，其荧光强度（FI）在整个消化过程中均得到监测，以跟踪胃黏度的变化。FG的FI和淀粉赋予的粘度遵循幂律关系。MR的发射不受TIM-1分泌液的成分或pH的影响。因此，直接测量消化物FI对模拟消化过程中的粘度变化很敏感。AP的粘度最高，其次是普通淀粉，高AM的粘度最低。在TIM-1胃室中，从最高到最低FI，因此粘度为高AM>高AP>普通玉米淀粉。我们得出结论，建议的方法的有效性，以促进体外腔内粘度的测量，当微粘度表示本体粘度（即，当在体积粘度的增加是分子聚集的结果和所述转子周围的周围环境是均匀的）。当食物是异质食物时，需要仔细考虑，因为分子转子仅报告其局部不均匀环境。