Preserving Abundance:
Innovative Strategies for Extending Shelf Life and Minimizing Food Waste.
The rapid increase in the global population (around 9.7 billion by 2050 estimated by the United Nations) urges a significant challenge to meeting the demands for fresh and wholesome food products.
Food and Agriculture Organization (FAO) estimates that 811 million people lack reliable access to food and 132 million face food insecurity worldwide. Further, variations in the climate and extreme weather events such as floods, and droughts lead to reduced availability and access to food. According to the Zero Hunger Sustainable Development Goal (SDG 2) the primary objective is to diminish hunger by 2030 through continuous and adequate access to nutritious foods regardless of economic and environmental factors. The limited shelf life of fresh foods is considered one of the major barriers to achieving this objective. Hence, we are seriously positioned to mitigate these challenges through sustainable approaches towards safeguarding food security despite climatic and economic vulnerabilities.
Traditional knowledge and practices that are centuries-old practices create a healthy balance between humans and the environment. Some of the traditional practices include crop rotation, seasonal and underutilized crop-eating, food preservation techniques like sun drying, fermentation, salting, pickling, and smoking, cooking techniques like root-stem cooking and nose-tail cooking, traditional storage methods like the use of clay pots and underground storage, and community sharing. Adopting these knowledge and practices offers sustainability, maximum retention and bioavailability of nutrients, and community resilience to food insecurity. However, adopting traditional practices alone may result in certain challenges including reduced efficiency in the mainstream food systems, lack of market access and commercialization, insufficient institutional support, and gaps in knowledge preservation and transfer.
Edible coating and films: Preserving the future of Food Security.
Several novel technologies for food preservation and minimizing food wastage have evolved as a result of the advancement in the fields of biotechnology, materials science, and digital technology. The postharvest loss of fresh fruits and vegetables is primarily associated with the factors that accelerate the microbial spoilage of fresh fruits and vegetables including high temperature and relative humidity. Novel packaging methods like controlled atmosphere packaging, modified atmospheric packaging, and intelligent packaging methods terminate the favorable factors for microbial spoilage, their application is limited due to their high cost.
Edible coatings and films are one such novel technology that can be safely consumed along with fresh products. This packaging method extends the shelf life of fresh commodities considerably by minimizing the exchange of moisture and gases. Since these packaging are biodegradable, they are considered as an innovative and green solution for conventional petroleum-based polymer packaging materials.
Natural biopolymers are used in the formulation of edible coating and films. Starch and protein are responsible for providing the structure for the packaging and improving the barrier properties against oxygen. Lipid is also an important constituent of edible coatings and films that act as a moisture barrier. Further, substances like plasticizers are added to improve film flexibility and reduce brittleness. Although numerous research has been carried out in developing edible films and coating using economically important starches worldwide, only a few research has been conducted in Sri Lanka in this field. Sri Lanka is known for its rich biodiversity. In Sri Lanka, around 240 plant species have been identified as underutilized crops, with numerous functional properties that have a high potential to be utilized in various food applications.
Dioscoreayams, Lasia spinosa, and Nelumbo nucifera, Maranta arundinacea (arrowroot)are some of the root and tuber crops in Sri Lanka where their extensive utilization in the food industry is limited. In contrast to the conventional starch sources, arrowroot (Maranta arundinacea L.) starch, exhibited excellent film-forming ability and gel-forming ability with improved mechanical and thermal properties. A recent study determined the application of arrowroot starch based edible coating on the post-harvest quality of tomatoes. Tomato is a highly perishable food commodity with a significant amount of post-harvest losses. The study demonstrated that the application of arrowroot starch based edible coating enriched with clove essential oil extended the postharvest shelf life of tomatoes for 48 days while securing the post-harvest quality. Thus, the findings of the research show a promising potential for the effective utilization of an underutilized starch arrowroot in the formulation of edible coating and films.
Waste Not: Transforming Food Waste into Food Security.
Growing consumer demand for natural food additives has encouraged researchers to find alternative plant-based compounds in place of synthetic food additives.
Numerous research studies have reported and concluded that plant-based compounds are rich in bioactive compounds. Functional properties including antioxidant activity and antimicrobial activity of the packaging could be enhanced by incorporating natural bioactive compounds. The previous study concluded that clove essential oil-enriched arrow-root starch-based edible coating resulted in a significant reduction of aerobic plate count and yeast and mold count during the tested period. In addition, the incorporation of clove essential oil revealed an increased antioxidant activity of tomatoes during the storage period.
Food by-products (i.e. peels, seeds, pomace, etc.) which has been generated in substantial amounts (approximately 1.3 billion tons of food) during food manufacturing are discarded as waste annually worldwide. Managing food waste is an expensive and crucial process as it imposes a huge burden on the environment.
These food by-products are often rich in essential nutrients such as dietary fiber, vitamins, minerals, antioxidants, and phytochemicals. Hence, these by-products can be used as a valuable source for nutrient enrichment of food products. Moreover, food by-products have also been considered rich sources of antioxidants and antimicrobial compounds and possess a high thermal stability. Hence, the application of the bioactive compounds extracted from food waste extends to diverse food applications and innovative packaging systems to extend the shelf life of food products. This approach also would be a cost-effective option and a sustainable approach to minimize waste generation
Food security is a critical challenge that should not be disregarded and requires a steady attention and action. Sustainable methods that benefit the environment are vital in the process of ensuring food security.
Key References
Lakshan, N.D., Senanayake, C.M., Liyanage, T. and Lankanayaka, A. (2024). Clove essential oil emulsions-loaded arrowroot starch-beeswax-based edible coating extends the shelf life and preserves the postharvest quality of fresh tomatoes (Solanum lycopersicum L.) stored at room temperature. Sustainable Food Technology. [online] doi:https://doi.org/10.1039/d4fb00033a
Dr. Chathuri Senanayake,
Senior Lecturer,
Department of Biosystems Technology,
Faculty of Technology,
University of Sri Jayewardenepura.