Healthy and functional ingredients from fruit processing byproducts: a review focusing on fruit peels

Fresh and processed fruits represent a large segment in the nutritional and functional food sector and are highly popular among the health-conscious consumers. And the food processing operations are striving to meet that increasing demand for nutritious food products. Consequently, the fast-growing fruit processing businesses across the world have been generating great quantities of waste by-products including peels, pomace, husk, pods, stems and seeds which are usually discarded as waste. Although such fruit waste by-products are rich in nutrients and some functional ingredients, the inappropriate utilization and disposal is creating huge environmental problems. Hence, effective utilization of these by-products is essential. At present small amounts of certain fruit wastes are used as fertilizer or animal feed. However, a better economical and scientific approach to benefit from such waste by-products is to use them as sources of functional and nutritional ingredients. Moreover, the notion of resource optimization from the processing wastes could be a practical step towards achieving sustainable food production systems. This review focuses on the various scientific aspects and potential approaches for the utilization of fruit processing waste by-products, with special reference to fruit peels, in the food and nutraceutical applications.