Dorra Sfayhi Terras, Farah Dridi, Nesrine Hadjyahia, Wafa Allouch, Youkabed Zarroug
Field Crop Laboratory (LR16INRAT02), National Institute of Agronomic Research of Tunisia, University of Carthage, Rue Hedi Karray, Ariana 2049, Tunisia.
Foods. 2022 Apr 6;11(7):1062. doi: 10.3390/foods11071062.
The objective of this study was to determine the influence of two types of dryers (hot air oven and vacuum dryer) and the yellow berry percentage (1.75%, 36.25%, 43.25%) on the drying process and phytochemical content of bulgur. Results showed that the Midilli model successfully described the moisture diffusion during drying at 60 °C in all bulgur samples, where an increase in yellow berry percentage generated an increase in moisture content. Effective diffusion coefficient (D) increased significantly ( ≤ 0.05) from 7.05 × 10 to 7.82 × 10 (m.s) and from 7.73 × 10 to 7.82 × 10 (m.s) for the hot air oven and vacuum dryer, respectively. However, it decreased significantly with a decrease of yellow berry percentage. It was concluded that the vacuum dryer provided faster and more effective drying than the hot air oven. Total polyphenol (TPC), total flavonoid (TFC), and yellow pigment contents (YPC) of bulgur were investigated. TPC ranged between 0.54 and 0.64 (mg GAE/g dm); TFC varied from 0.48 to 0.61 (mg QE/g dm). The YPC was found to be between 0.066 and 0.079 (mg ß-carotene/100g dm). Yellow berry percentage positively and significantly affected the TPC, TFC, and YPC contents due to the hard separation of the outer layers from the starchy grain during the debranning step.
本研究的目的是确定两种干燥机（热风烘箱和真空干燥机）以及黄粒小麦百分比（1.75%、36.25%、43.25%）对碎粒干燥过程和植物化学成分的影响。结果表明，Midilli模型成功描述了所有碎粒样品在60℃干燥过程中的水分扩散情况，其中黄粒小麦百分比的增加导致水分含量增加。热风烘箱和真空干燥机的有效扩散系数（D）分别从7.05×10显著增加（≤0.05）到7.82×10（m²/s）和从7.73×10增加到7.82×10（m²/s）。然而，随着黄粒小麦百分比的降低，有效扩散系数显著下降。得出的结论是，真空干燥机比热风烘箱提供更快、更有效的干燥。对碎粒的总多酚（TPC）、总黄酮（TFC）和黄色色素含量（YPC）进行了研究。TPC范围在0.54至0.64（mg GAE/g干物质）之间；TFC在0.48至0.61（mg QE/g干物质）之间变化。发现YPC在0.066至0.079（mg β-胡萝卜素/100g干物质）之间。由于在脱皮步骤中淀粉粒外层的硬分离，黄粒小麦百分比对TPC、TFC和YPC含量有正向且显著的影响。
