Valorization of agro-industrial waste in composite films for sustainable packaging applications

Abstract

The increase in general awareness about environmental hazards caused by petrochemical plastics has substantially increased the necessity of eco-friendly substitutes for plastics. Conventional plastics in addition to being non-biodegradable are also derived from depleting non-renewable resources. Therefore, the production of packaging films utilizing agro-industrial waste has gained widespread attention as a sustainable alternative to conventional non-degradable plastic. The underutilized compounds from agro-industrial waste such as by-products of fruit and vegetable industries or the waste from sugar industries can serve as a great alternative for plastics owing to their low cost, availability and abundance of raw materials. They possess significant physical and chemical properties which make them good sources for producing biopolymers as well as cellulosic fillers. The processing and production of food products by agro-industries generate waste or by-products such as husks of various grains, leaves, gums, bagasse, offal and seeds, which contain an ample amount of plant-derived fibrous proteins such as pectin, starch and cellulose. They also have nutritional properties and peculiar sensory properties which are obliged to the bioactive compounds found in them. Therefore, these waste materials can be reutilized for recycling along with high value-added purposes which will reduce environmental stress and empower sustainable greener approaches. This review will provide a discussion on the usage of agro-industrial wastes for fabricating sustainable composite films with several reinforcements. Additionally, the significance of waste-derived biopolymers as films having value-added functional packaging properties over conventional packaging films will also be discussed. This usage of agro-industrial waste material in turn would aid in the circular economy flow, waste reduction along with generation of high-end usage and recycling of waste.