State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, People's Republic of China.
Institute of Environment Science and Engineering, School of Civil and Environment Engineering, National University of Sciences and Technology, Islamabad, Pakistan.
Crit Rev Biotechnol. 2022 Dec;42(8):1284-1303. doi: 10.1080/07388551.2021.2002805. Epub 2021 Dec 2.
Orange peel waste (OPW), a discarded part of orange fruit, is a rich source of essential constituents that can be transformed into highly value-added bioproducts. OPW is being generated in million tonnes globally and returns to the environment without complete benefit. Thus, a high volume of annually produced OPW in the industry requires effective valorization. In this regard, limited data is available that summarizes the broader spectrum for the sustainable fate of OPW to produce value-added bioproducts. The main objective of this treatise is to explore the sustainable production of bioproducts from OPW. Therefore, this review covers all the aspects of OPW, from its production to complete valorization. The review encompasses the extraction technologies employed for extracting different valuable bioactive compounds, such as: essential oil (EO), pectin, and carotenoids, from OPW. Furthermore, the suitability of bioconversion technologies (digestion/fermentation) in transforming OPW to other useful bioproducts, such as: biochemicals (lactic acid and succinic acid), biopolysaccharides (xanthan and curdlan gum), and bioenergy (biomethane and bioethanol) is discussed. Also, it includes the concept of OPW-based biorefineries and their development that shall play a definite role in future to cover demands for: food, chemicals, materials, fuels, power, and heat. Lastly, this review focuses on OPW-supplemented functional food products such as: beverages, yogurts, and extruded products. In conclusion, insights provided in this review maximize the potential of OPW for commercial purposes, leading to a safe, and waste-free environment.
橙皮废料（OPW）是橙子果实的废弃部分，是丰富的必需成分来源，可以转化为高附加值的生物制品。全球每年产生数以百万吨计的 OPW，却没有得到充分利用而返回环境。因此，工业界每年大量产生的 OPW 需要得到有效利用。在这方面，可用于总结 OPW 生产高附加值生物制品的可持续命运的综合数据有限。本文的主要目的是探索 OPW 生产生物制品的可持续途径。因此，本综述涵盖了 OPW 从生产到完全利用的各个方面。综述包括从 OPW 中提取不同有价值的生物活性化合物（如精油（EO）、果胶和类胡萝卜素）的提取技术。此外，还讨论了生物转化技术（消化/发酵）在将 OPW 转化为其他有用生物制品（如生化物质（乳酸和琥珀酸）、生物多糖（黄原胶和结冷胶）和生物能源（生物甲烷和生物乙醇））方面的适用性。还包括基于 OPW 的生物炼制厂及其发展的概念，它们将在未来发挥明确的作用，以满足对食品、化学品、材料、燃料、电力和热量的需求。最后，本综述重点介绍了添加 OPW 的功能性食品产品，如饮料、酸奶和挤压产品。总之，本文提供的见解最大限度地提高了 OPW 在商业用途方面的潜力，实现了安全和无废物的环境。
