Vegetables: Wastes, Byproducts, and Utilization

Food waste is generated in abundant amounts in agricultural lands during production, harvest, sorting, or as industrial waste during product development, or in households during the preparation of meals. The waste is produced throughout the supply chain from harvesting to its final consumption, which needs to be utilized in the best possible way, without having invested huge amounts in it and without creating environmental hazards, supporting the concept of a circular economy. The FAO has estimated the global volume of food wastage at 1.6 billion tons of food waste, which also accounts for 1.3 billion tons of “wastage of edible portions.” Most of the food wastage ends up in landfills and gets completely rotten, contributing to greenhouse gas emissions from these dumping grounds. Since vegetable wastes are perishable in nature, actions to utilize these wastes need to be quick. Recent research has documented the generation of renewable energy by bioconversion as one of the proficient means of utilizing these vegetable wastes, in addition to strategies like farm animal nutrition, production of nutraceuticals deriving fibers from various vegetables, or derivation of bioactive compounds like antioxidants, minerals, 78 polyphenolic compounds, and so forth. The use of modern techniques like pulsed electric fields, hydrostatic pressure, and radiation are widely being used to put the waste to its best use, though every advantage comes with certain drawbacks, which need to be understood before putting it into use. India is indubitably the largest global agricultural powerhouse. A growing population will exacerbate further food insecurity. Diet habits are changing with the growing population, which leads to alteration in the production and processing of foods to meet the increased demands. The processing of food generates 25–30% waste of the absolute product. The FAO has estimated the global volume of food wastage at 1.6 billion tons of food waste, which also accounts for 1.3 billion tons of “wastage of edible portions.” According to MOHUA, it has been estimated that India produces about 42.0 million tons of municipal solid waste (MSW) annually. The per capita waste generation in major Indian cities ranges from 0.2 kgs to 0.6 kgs. Out of the total municipal waste collected, on average, 94% is dumped on land, and 5% is composted, which results in environmental hazards. The waste is produced throughout the supply chain from harvesting to its final consumption, which needs to be utilized in the best possible way. The Sustainable Development Goals (SDGs) also accentuate food security and sustainability, which emphasizes designing a better way to ensure sustainable consumption and production patterns. Vegetable waste majorly contains potential bioactive compounds, which can be further processed and utilized in different industries such as the health industry (pharmaceutical), food industry, and textile industry. This chapter describes the nature of the waste generated from vegetables, modern techniques of processing, the bioactive components, and the potential techniques to minimize and utilize its byproducts.