Dietary Fiber in Wine

Indigestible polysaccharides are major constituents of dietary fiber. Polysaccharides in wine are usually studied in relation to sensory properties but a nutritional approach is also appropriate for this wine fraction. Grape pomace is rich in dietary fiber, and a significant amount of this fiber may pass into wine during the winemaking process; however, food composition tables report zero dietary fiber content for wines. The objective of this work was to ascertain whether dietary fiber is a common constituent of wine. Soluble dietary fiber was determined in several red and white wines from different Spanish regions by using a newly developed four-step analytical method: concentration of wine, enzymatic treatment, dialysis, and dietary fiber determination. Significant amounts of soluble dietary fiber were found in wine; dietary fiber content was higher in red wine (0.94 to 1.37 g/L) than in white wine (0.19 to 0.39 g/L).