No abstract

Citrus is the largest fruit crop worldwide. Meanwhile, oranges account for 60% of the total, with their main application in juice production. During orange juice production, only about 50% of the fresh orange weight is transformed into juice, with the remaining 50% comprised of residue (peel, pulp, seeds, orange leaves and whole orange fruits that do not reach the quality requirements). With the resulting tons of orange byproducts, there has been an initiative to research possible ways to reutilize and revalorize citrus waste. Orange pomace, the byproduct from juicing process, is currently used to extract the essential oils for fragrance and flavor, and a majority of the waste is used as cattle feed; however, these applications do not account for all of the waste or capture all of its potential value. Meanwhile, these byproducts are put into landfills at the owner’s expense, and contribute to global warming through carbon emissions. On the other hand, orange byproducts still contain many useful nutraceutical components, such as dietary fiber and phytochemicals, which could be utilized for value-added ingredients and new product development. Some research approaches in this area include the production of organic fertilizers and biofuels, or the extraction of essential oils, pectins, and antioxidant compounds. There is little information in the literature and in the food industry in terms of utilizing the orange pomace directly or with some simple treatments. Orange pomace may be used for food product development as a “clean-label”, non-synthetic preservative, which rationalizes this review.