Effects of soluble and insoluble fractions of fruit pomaces on short-chain fatty acid generation by fecal microbiota in vitro

OpenAlex İngilizce

This study investigated the dietary fiber composition, monosaccharide profile, and prebiotic potential of fruit pomaces (apple, apricot, peach, and grape). Insoluble fiber (IF) was predominant in all samples, with apple (74.37%) and grape pomace (74.06%) having the highest IF contents. The highest soluble fiber (SF) was detected in peach pomace (18.71%), while grape pomace had the lowest (6.55%). Monosaccharide analysis showed that glucose was the major sugar in both SF and IF fractions, followed by arabinose, galactose, mannose, xylose, and rhamnose. Fucose was not detected. Apricot and apple pomaces exhibited the highest levels of neutral sugars and uronic acids, suggesting a richer presence of pectic substances and hemicelluloses. Despite grape pomace having the highest phenolic content and antioxidant capacity, its low SF content limited SCFA (short-chain fatty acid) production during in-vitro fecal fermentation. In contrast, apple pomace—with a more balanced SF/IF profile and richer monosaccharide diversity—induced significantly higher acetate, propionate, and butyrate levels (P<0.05). These results highlight the importance of not just fiber quantity, but also solubility and sugar composition, in determining the prebiotic efficacy of fruit pomace fibers. Among the pomaces evaluated, apple pomace displayed compositional characteristics that may warrant further investigation for potential prebiotic applications.