Microwave Heating: A Game-Changer for Sustainable Agriculture

Fresh produce is an excellent source of essential vitamins, minerals and antioxidants. Over the past few decades, consumers have become inclined to eat these products because of their potential preventive effects against some chronic diseases. In addition, increasing safety and traceability are important issues for all those involved in the supply chain (from farm to fork). Therefore, the quality of a food product has a significant impact on its acceptance by consumers. Crops are metabolically active and perishable and are subject to quality degradation due to ripening and senescence processes. These processes are often associated with the development of spoilage microorganisms and other undesirable phenomena that must be controlled to maintain quality and extend shelf life during storage. High water activity and the presence of nutrient factors associated with these foods can also promote pathogen growth. There is important economic value in fruits and vegetables with better sensory and nutritional attributes. It is therefore important that appropriate preservation practices are used because otherwise, there will be a crucial loss of nutritional and quality attributes, as well as negative economic impacts throughout the supply chain, from grower to consumer. Furthermore, the volume of internationally traded agricultural products has increased with food globalization. This has lengthened the distance and duration of transportation. As a result, prolonged exposure to suboptimal storage conditions can degrade product quality, leading to loss and waste. So, extending the shelf life of products and using more advanced technology to control quality over longer distances have become key issues. Proper postharvest handling can (1) slow biological processes caused by senescence and ripening, (2) reduce or inhibit the development of physiological disorders, and (3) cut microbial growth and contamination. This handling includes storage time and temperature management, relative humidity, chemical and/or physical treatments, and packaging. Today, there is a great deal of research into the effects of new physical and chemical post-harvest technologies to maintain the quality, nutritional value and safety of fresh produce (from harvest to consumer). These technologies have been shown to preserve key quality and nutritional attributes of fruits and vegetables, either alone or in combination with appropriate storage temperature management. The Wonders of Microwave Heating The University of Foggia (Italy) published in 2022, an in-depth collection of research?conducted in recent years on the main applications of new physical and chemical technologies for preserving the quality and reducing the loss and waste of fresh fruits and vegetables. Among these new methods, microwave heating stands out for reducing the microbial load, thus helping to preserve the freshness and quality characteristics of fruits and vegetables. In general, heating processes such as hot water and hot air treatments, high temperatures/short time treatments, and radio frequency can cause a reduction in the content of essential nutrients and flavor-related compounds due to the application of heat and its slow distribution in plant tissues by conduction or diffusion processes.? Microwave heating has been used to achieve a rapid and effective temperature increase without a temperature gradient as an alternative to conventional heating. With this technique, fruits and vegetables are treated for a short time to control microbial growth during the minimal processing of the product, minimizing quality losses and at the same time guaranteeing the lowest environmental impact and the absence of residues in the treated product. A study published by the Islamic University of Science and?Technology (India) in 2020 summarizes the advantages of using microwave heating to reduce microbial load: Compared to conventional heat treatment, microwave heating shows lower energy consumption with materials having improved sensory attributes.? The recovery rate and final moisture content are reduced due to microwave heating with hot air. Microwave cooking is able to (1) preserve antioxidant activity and bioactive constituents in vegetables, and (2) improve the in vitro protein digestibility of foods by reducing antinutritional factors. Microwave heating results in minimal color changes, antioxidant activity and bioactive compounds due to the inactivation of enzyme activity and shorter processing time. Closing Remarks In order to improve the safety of the products and thus extend their shelf life, physical treatments such as microwaving were found to be helpful. Application of this technique by the end user could increase the satisfaction of those involved in the supply chain and thus improve the quality of the process. However, this requires portable tools that can be used on industrial lines or in the field. At the same time, new technologies are being explored to extend shelf life and enable continuous monitoring of product quality at all stages of the supply chain. Author:?Jorge Luis?Alonso G. (with ChatGPT)?Maximizing Agribusiness Profits with Expert Postharvest Storage Strategies | Horticultural Writing Specialist.?This article was written exclusively for the business platform Postharvest. Cover photo by?Byju?s - Microwave, Electromagnetic Spectrum, What is Electromagnetic Spectrum?