Short Chain Fatty Acid Production from Brussels Sprouts, Red Cabbage, and White Cabbage Following In vitro Digestion and Fecal Fermentation

White cabbage, red cabbage, and brussels sprouts, belonging to the Brassica genus, are widely consumed vegetables and serve as important dietary fiber sources. The aim of this study was to compare the dietary fiber characteristics of these cabbage cultivars and to evaluate their fermentation behavior in the gut, with a particular focus on short chain fatty acid (SCFA) production. Free sugar contents of each cabbage cultivar, specifically the levels of glucose, fructose, and sucrose, were measured by high performance liquid chromatography (HPLC). Lyophilized red cabbage, white cabbage, and brussels sprouts were subjected to in vitro upper gastrointestinal digestion to obtain dietary fiber fractions, which were subsequently characterized using Gas Chromatography /Mass Spectrometry and spectrophotometry. The obtained dietary fibers were then subjected to in vitro fecal fermentation assay using fecal material collected from three healthy donors. SCFA production and total gas formation were monitored at 0, 6, 12, 24, and 48 h of fermentation. The results showed that total free sugar contents of the samples were statistically (P < 0.05) different from each other with white cabbage having the highest free sugar content (3.6%, wet basis), followed by red cabbage (2.9%, wet basis), and brussels sprouts (2.3%, wet basis). Uronic acid and glucose were the dominant monosaccharide moieties of dietary fibers across all cabbage cultivars. However, dietary fibers of brussels sprouts were distinguished by significantly (P < 0.05) lower glucose but higher galactose and arabinose contents, suggesting a higher proportion of soluble dietary fiber. Accordingly, dietary fibers from brussels sprouts exhibited a faster fermentation rate than those from white and red cabbage. Interestingly, dietary fibers from all cabbage cultivars produced acetate and butyrate at levels comparable to inulin, a well-known butyrate-promoting prebiotic, though fermentation occurred at a slower rate. Collectively, these findings demonstrate that dietary fibers from white cabbage, red cabbage, and brussels sprouts can stimulate microbial SCFA production in a species-specific manner, highlighting their potential physiological relevance for human gut health.