Chemical Composition and Functional Characteristics of Dietary Fibers from Pingguoli Pear (Pyrus Bretschneideri Rehd. cv. Pingguoli Pear)

In this study, apple–pear pomace dietary fibers were treated with acid, alkali, cellulase, and hemicellulase. The effects of these treatments on the chemical constitutions, structural characteristics, functional properties, and the quality of apple–pear pomace dietary fibers were investigated. The results showed that the purity of apple–pear pomace dietary fibers was 79–83%, and the fiber contained cellulose, hemicellulose, pectin, and lignin. Their monosaccharide structures included mannose, glucosamine, ribose, rhamnose, glucuronic acid, galacturonic acid, galactosamine, glucose, galactose, xylose, arabinose, and fucose. The scanning electron microscopy showed that all the apple–pear pomace dietary fibers were beehive shaped, but their functional and physico-chemical properties were different. Using the main constituents and the functional and physico-chemical properties as indicators, through a principal component analysis, we determined the main constituents and characteristics of four apple–pear pomace dietary fibers.