This research aimed to explore the effect of nonthermal (High-Pressure Processing) and thermal (High-Temperature Short-Time) pasteurization applied to a fruit and vegetable based smoothie on the bioaccessibility of (poly)phenols and their biotransformation by human gut microbiota. Untreated and pasteurized smoothies were subjected to an in vitro gastrointestinal digestion and colonic fermentation. Native (poly)phenols and their gut-related metabolites were analyzed by LC-MS. Both pasteurization techniques showed a protective effect against degradation of (poly)phenols along the gastrointestinal tract. Thermal processing led to a more than 2-fold higher (poly)phenol bioaccessibility (44%) compared to the untreated (17%) and nonthermally treated (21%) smoothies. Native (poly)phenols were almost completely converted (83-87%) into low-molecular-weight catabolites by the gut microbiota in all smoothies. However, thermal treatment favored the generation of gut-related metabolites after colonic fermentation for 48 h compared to untreated and high pressure-treated smoothies, mainly due to the improved bioaccessibility observed after in vitro gastrointestinal digestion.

Keywords: (Poly)phenols; Fruit and vegetable based smoothies; Gastrointestinal bioaccessibility; High-Pressure Processing; Human gut metabolism; Thermal Processing.

本研究旨在探讨非热（高压处理）和热（高温短时间）巴氏杀菌对基于水果和蔬菜的奶昔中多酚生物可及性及其在人体肠道菌群中的生物转化的影响。未经处理和经过巴氏杀菌处理的奶昔接受了体外胃肠消化和结肠发酵过程。通过LC-MS分析了天然多酚及其与肠道相关的代谢物。两种巴氏杀菌技术都表现出对整个胃肠道中多酚降解的保护作用。热加工导致多酚生物可及性比未经处理（17%）和平压处理过的（21%）奶昔高出两倍以上，达到44%。所有奶昔中的天然多酚几乎完全转化为低分子量代谢物，转化率为83-87%，这是肠道菌群作用的结果。然而，热处理在结肠发酵48小时后更有利于生成与肠道相关的代谢产物，这主要归因于体外胃肠消化过程中观察到的生物可及性的提高。

关键词：多酚；基于水果和蔬菜的奶昔；胃肠道生物可及性；高压处理；人体肠道代谢；热加工。