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Promising Agro-Wastes for Food Packaging

L. Susmita Devi, Avik Mukherjee and Santosh Kumar*

Department of Food Engineering and Technology, Central Institute of Technology Kokrajhar, Kokrajhar, BTR, Assam, India

Abstract

The agricultural sector produces a substantial amount of waste, typically left unused, and these wastes are a growing risk to human health, food security, and the environment. Transforming these waste materials into valuable products holds the potential to be advantageous for both the environment and significant cost savings. Agro- and food wastes originating from various sources have the potential to serve as a primary resource for creating value-added products, extracting food-related compounds, and producing biopolymers for sustainable food packaging. The increasing consumer demand has spurred the development of new eco-friendly food packaging, leading the packaging industry to focus on creating sustainable, renewable, biodegradable, and environment-friendly packaging materials from agro-based resources. Moreover, these agro-based materials hold immense potential for replacing petrochemical-based plastics in the packaging sector due to their abundant availability and biodegradable nature. Various agro-wastes, and their potential for extraction of different natural biopolymers, and bioactive compounds are discussed in detail in this chapter. In addition, the applications of agro-waste-based biopolymers and bioactive compounds in biodegradable sustainable food packaging systems have also been discussed. The chapter also delves into future considerations, particularly in the realm of enhancing the effectiveness and efficiency of agro-waste packaging systems, while simultaneously addressing the inherent production challenges. This article holds particular significance within the context of the biorefinery concept, which is dedicated to the conversion of agricultural waste into a diverse range of valuable products.

Keywords: Solid waste, sustainable packaging, biopolymers, organic compounds, eco-friendly

1.1 Introduction

Rapid urbanization, population growth, and industrialization generate a vast amount of agro-waste every year [1]. Agro-wastes are the residue left after processing and producing different agro-products, such as fruits, vegetables, muscle foods, and dairy products that are liquids, slurries, or solids in nature [2]. These wastes are generally left untreated or unutilized and are either burned on-site, disposed of by dumping, or unplanned landfilling, leading to climate change by increasing greenhouse gas emissions causing a threat to the environment and human health [3, 4]. The lack of efficient waste management techniques creates a huge challenge for mankind to deal with such massive food and agro-wastes. Most of the food wastes are generated during production, harvesting, transportation, industrial processing, and consumption [5]. Agro-wastes have the potential to be used as raw materials for value-added products, renewable energy production, extraction of food compounds, and packaging material manufacturing [6]. Agro-industry byproducts are also composed of numerous bioactive compounds such as carbohydrates, proteins, and lipids that can be extracted and used to produce biodegradable food packaging [7]. Agro- and food wastes are rich in nutrients and organic compounds that can be processed to recover valuable products including biopolymers [8]. The biopolymers are directly extracted either by chemical synthesis or by genetically modified organisms from agro-industrial wastes and can be converted into biodegradable packaging materials. However, the treatment methods or downstream processing of such waste are usually complex, expensive, and time-consuming and cause secondary pollutants due to their heterogeneous nature [3]. On the other hand, waste generated from the food industries is extremely nutritious in nature, making substrates for microbial fermentation and enzyme production [9]. The oil industries also produce a large number of residues known as oil cakes that contain high concentrations of fats, oils, greases, suspended solids, and dissolved solids, contributing to air, water, and solid waste pollution [8]. Such environmental problems can be reduced or minimized if these wastes are utilized for the extraction of biopolymers and other valuable products.

Food packaging serves as a vital part of the food system that protects food and food products from degradation and damage, maintains food safety and hygiene, enhances shelf life, and reduces food waste and food losses [10]. A wide variety of synthetic plastic materials are being used in food packaging that raise environmental pollution concerns [11]. The food packaging sector consumes the largest amounts of synthetic plastics globally, and it is the primary contributor to synthetic plastic waste [12]. Waste generated from food packaging accounts for about 66% of total packaging waste, and thus, there is a growing prerequisite for sustainable and biodegradable packaging materials that have the desired physical, mechanical, and barrier properties for food packaging applications. Biopolymers derived from bioresources, i.e., agro- and food wastes have shown potential for use as food packaging (Figure 1.1). Extraction and purification of the biopolymers from agro-wastes to produce a food packaging material can replace petrochemical-based synthetic plastics in the food packaging industry [1]. The growing market for food delivery services is expected to boost packaging material consumption in the future, and a sustainable approach to materials development requires agro- and food waste-based materials to fill the gap between industrial supply and consumer demand [13]. The major benefits of agro-waste valorization include nontoxicity, improving ecosystems, encouraging circular economy, increasing employment, and biocompatibility with other materials [14, 15]. This chapter presents a summary of the potential uses of agro-wastes for the extraction of biopolymers for technological applications. Furthermore, the chapter summarizes existing information concerning various waste types of agro-wastes and their treatment for extracting valuable compounds for applications in the sustainable food packaging sector.

Figure 1.1 Utilization of agro- and food wastes in sustainable food packaging [16].

1.2 Current Global Status of Agro-Wastes

Solid waste generation increases with the growing population, urbanization, industrialization, living standards, disposable incomes, and consumption of goods and services [17]. In the last century, China, India, and Africa have experienced significant increases in agro-waste generation alongside rapid population growth and economic development. In India, agro-waste remains the predominant form of solid waste, with annual production ranging from 350 to 990 million tonnes (Mt). India produces more than 130 Mt of paddy straw each year, of which half is used as animal feed and the other half is dumped, making it the second-largest producer of agricultural waste in the world after China [18]. Approximately 34% of Asia's biomass residues are burned in the field, and open-field burning of crop residues contributes significantly to greenhouse gas emissions in countries like China and India [19]. Managing these solid wastes is a worldwide problem because waste collection, transportation, segregation, treatment, and disposal are complex processes and have detrimental effects on the environment. Additionally, inappropriate solid waste management results in several environmental pollutions and health problems including waterborne diseases, respiratory illnesses, soil pollution, and groundwater contamination [20]. Thus, it is important to identify efficient ways of utilizing and managing agro-residues. These agro-wastes can be utilized in different food sectors, however, lack of knowledge about their characterization and processing methods hinders their applications in the food sector [19]. The global economy is planning an integral waste management strategy, which is based on the concept of biorefinery and on the reduction, reuse, and recycling of waste with the goal of recovering resources derived from wastes as renewable resources [21]. Agriculture being one of the largest sectors with the highest waste production becomes an essential part of the bioeconomy, which promotes the conversion of agro-wastes into value-added products such as bioenergy, bioproducts, feed, and foods [22]. The increasing global population accelerates over utilization of natural resources and generates a large amount of waste, which is expected to double by 2050 to 4 billion tonnes at the current rate of production and consumption [23]. Agro-residues obtained after harvesting grains are used in different applications such as animal feed, raw material for animal bedding, loose-fill insulation, fuels, composites, bioplastics, biorefineries, and as raw material in the paper and pulp industry, as an absorbent of uranium residues, and as a substrate for solid state for microbial growth [1, 24].

The global population has increased from 3.7 billion to 8.0 billion during 1970-2022, and it is predicted to reach 8.5 billion, 9.7 billion, and 11.2 billion by 2030, 2050, and 2100, respectively. As a result, ensuring food security in the future would be a formidable challenge, and fulfilling the high demand of a growing...