Apple

Abstract

Apple is used for the production of a variety of products, among the most important are apple juice, cider, vinegar, jam, sauce, fresh apple slices, dry, and canned apple. The highest share of apple, apart from fresh eating apples, is used for the production of apple fruit juice and concentrated juice. Apple juice production generates approximately 25% of by-products such as apple pomace, apple peel, and apple seed. Applications of apple processing by-products are still mostly focused on applications of apple pomace. Apple pomace is traditionally used as a crude feed, or for composting. Owing to the high carbohydrate content, apple pomace, as a low-cost agroindustrial waste, can be used as a substrate in a number of microbial processes for the production of various value-added products such as organic acids, enzymes, ethanol, etc. The application of apple pomace in the production of biscuits and related products has been reported. Much research has been devoted to the study of the extraction of apple pomace, mostly due to the high content of different polyphenolic groups. Yet apple pomace is still mostly used for the production of pectin and this represents one of the most practical and the most widespread approaches for valorization.