Food Loss and Waste Reduction

Technical Solutions for Cleaner Production

Laxmikant S. Badwaik, Cristóbal Noé Aguilar, A. K. Haghi, Laxmikant S. Badwaik, Cristóbal Noé Aguilar, A. K. Haghi

• Publisher: Apple Academic Press
• Year: 2021
• ISBN:
  9781000168952
• Edition: 1
• Topic: Biowissenschaften
• Subtopic: Wissenschaft Allgemein

Focusing on the crucial sustainability challenge of reducing food loss at the level of consumer society, this volume provides an in-depth, research-based overview of this multifaceted problem. It considers the myriad environmental, economic, social, and ethical factors associated with the enormous amount of food waste, which also end up wasting water, air, electricity, and fuel, which are necessary for food processing.

This book uniquely examines the social and cultural views of food waste management, shedding new light on the topic by emphasizing the consumer/household perspective throughout. Drawing on a wide variety of disciplines, the book presents philosophical reflections, practical examples and case studies, and potential solutions to the problem of increasing food waste.

CHAPTER 1 Application of Hydrogels in Food Packaging to Protect Food Loss

ANURAG SINGH* and DHRUV THAKUR
Department of Food Science and Technology, National Institute of Food Technology Entrepreneurship and Management (NIFTEM), Sonipat, Haryana, India
*Corresponding author. E-mail: [email protected]

ABSTRACT

Hydrogels are three-dimensional, hydrophilic, polymeric networks capable of absorbing large amounts of water or biological fluids which may be prepared either by natural or synthetic sources. The issue of food loss and waste (FLW) has been receiving increased attention lately. This interest is valid as about one-third of food produced around the world is either wasted or lost as stated by the Food and Agriculture Organization. Packaging plays a vital role in minimizing the wastage of food by increasing its shelf life and protecting it from external factors. One of the important advances in this field is the use of hydrogels as a packaging material. Since synthetic hydrogels are mostly non-biodegradable and are toxic in nature, natural polymers are majorly used for preparing hydrogels as they are biodegradable and can be used as edible packaging also. Majorly used natural polymers for preparing hydrogels are polysaccharides, proteins and lipids. The chapter discusses various aspects related to the use of these hydrogels in food packaging in order to reduce the food loss.

1.1 INTRODUCTION

In 1936, a paper on methacrylic polymers was published by researchers from DuPont. Poly(2-hydroxyethyl methacrylate), for example, pHEMA has been mentioned in this paper and it was described as a difficult, fragile, and vitreous plastic and was obviously not deemed important. Poly-HEMA was largely overlooked until 1960 after that article. In the presence of water or other solvents, Wichterle and Lim discussed polymerization of HEMA and cross-linking agents. They acquired smooth, water-growing, elastic, and clear gel instead of brittle polymers. As we understand them today, this development has resulted in the contemporary field of hydrogels. After that, over the years, the number of formulations for hydrogel has steadily increased.¹ Hydrophilic group macromolecules such as –OH, –COOH, –SO₃H, –CONH, and –CONH₂ make up hydrogels, which are integrated and incorporated in the plastic backbones. Some physical properties of hydrogels, when fully hydrated, are similar to that of living tissue and natural rubber. Hydrogels are now regarded omnipresent in biomedical, medicinal, and usable food markets across a wide spectrum. Hydrogels are made either from artificial polymers such as pHEMA or natural ones like polysaccharides (cellulose), lipids (waxes) as well as proteins (milk proteins).^2–9

Hydrogels are three-dimensional, hydrophilic, polymeric networks capable of absorbing large amounts of water or biological fluids.¹⁰ Scientists have described hydrogels in various ways over the years. Mostly used definition states hydrogel is a water-swollen, cross-linked network of polymers, generated with the help of one or more monomers. Due to their outstanding promise in a broad spectrum of applications, hydrogels have earned significant attention over the previous 50 years. Because of their high water content, they are quite comparable to natural tissue in terms of their flexible nature.¹¹ They have a strong water affinity, but their chemically or physically crosslinked structure prevents them from dissolving.⁹ Hydrogels can degrade and eventually break up and dissolve or become stable chemically. These are referred to as physical or reversible gels when the networks are held together by molecular and/or secondary forces, such as ionic, binding, and hydrophobic forces.¹² Hydrogels’ competency of imbibing water is because of the hydrophilic groups linked to a polymeric base, whereas because of the cross-links of network chains it is resistant to dissociation.¹¹ Hydrogels are more similar to living tissue in their physical properties than any other group of synthetic biomaterials. In general, the relatively high amount of water and smooth, rubbery texture give them a close, superficial connection to a living soft tissue.¹³

Hydrogels can be developed in various forms, including plates, nanoparticles, microparticles, films, and coatings. Thus, they find many different applications in various industries.¹⁴ For physical and chemical hydrogels, there are many distinct macromolecular structures. They include crosslinked networks of linear homopolymers, linear copolymers, and block or graft copolymers; multivalent ion polyion, polyion–polyion or H-bonded complexes; hydrophilic networks stabilized by hydrophobic domains; and interpenetrating polymer network (IPN) or physical blends. Physical forms include (1) solid molded form, (2) pressed powder matrices, (3) microparticles, (4) coatings, (5) membranes or sheets (6) encapsulated solids, and (7) liquids.¹²

To demonstrate proper physical and chemical properties, preparation of a function-specific hydrogel requires various scientific approaches. Mostly used techniques for producing hydrogel networks are solution and suspension polymerization. They provide molecular structural control, response to stimuli, mechanical strength, biodegradation, and solubility.¹ Earlier, much attention was given to synthetic polymeric materials. But with time, natural materials have grasped the attention of researchers towards them as a result of their amazing properties. Another major factor for their growth is the negative effects of synthetic plastic materials on environment, health, and ecology.¹⁵

1.2 BRIEF OVERVIEW OF FOOD WASTAGE IN INDIA

Food wastage as defined by the Food and Agriculture Organization (FAO) is “wholesome edible material intended for human consumption, arising at any point in the food supply chain that is instead discarded, lost or degrade.”¹⁶ In recent years, the issue of food loss and waste (FLW) has received increasing attention as a central feature of the challenges and inefficiencies, which characterize the global food system and consequently its social, economic, and environmental implications. According to FAO of the UN, an approximate one-third of food produced around the world is either wasted or lost. This is unfair in an era in which almost 1 billion people go hungry. FLW is a misuse of the labor, water, power, land, and other natural resources that were used for its production.

India is the world’s second-largest population. Government announced in 2012 that nearly 22% of the Indian population lived below the poverty line. According to estimates from the FAO in the report “The State of World Food Security and Nutrition, 2017,” 190.7 million people in India are undernourished. This accounts for 14.5% of the Indian population, making India the home of the world’s largest undernourished population. However, the UN reports that almost 40% of India’s food is wasted or lost which every year costs 1 lakh crore rupees. It is predicted that food production in India will double in the next 10 years; but a cause for concern is postharvest loss of about 35–40% of the total annual output accounting to 58,000 crore.¹⁷

One of the ways of minimizing the food loss and wastage is by the use of efficient packaging. To avoid handling and in transit losses, fresh-produced items require appropriate packaging. Lack of novel methods of packaging results in a decline in the quality of food, which also contributes to food waste.¹⁶ Hence, an overall improvement in packaging methods is required which will help in controlling the food wastage of the country. Not only does it help in controlling food wastage, but also provides other functions like containment of food and protection from the external environment. These functions help in proper preservation of food and thus improve the shelf life.

We feel proud because we produce one of the largest quantities of foods in the world but we should also be worried to be the first among all in the wastage as...