Interactions Between Pre-harvest, Post-harvest Handling and Welfare of Fish for Sustainability in the Aquaculture Sector

Abstract

Fish and other aquatic products are nutrient-dense and a relatively accessible source of animal protein that transcends various social and cultural norms. The demand for fish has been steadily rising and now significantly outweighs the supply due to the world’s acceptance of fish and its products. However, because of their biological makeup and the presence of autolytic enzymes, fish are highly perishable and require careful welfare handling techniques to prevent spoilage. Furthermore, the presence of enzymes and microbes speeds up the rate of fish product spoilage, increases post-harvest waste and lowers the quality of fish products, which could result in foodborne illness if consumed. However, to make fish available for consumption, several processes must be carried out, including feed withdrawal (fasting), air exposure, crowding within the equipment, handling, sorting and loading. The quality and nutritional value of fish products are ultimately determined by these pre- and post-harvest procedures. It is interesting to note that pre- and post-harvest practices are emerging welfare concerns in fish farming that have a significant impact on the productivity of these aquatic products, their shelf life and fish sustainability in the aquaculture industry. The texture and colour of the flesh, an increase in lactic acid production and a decrease in muscular pH are all signs of compromised welfare and the beginning of spoilage during pre- and post-harvest handling activities of fish. This hastens the onset of rigor mortis and spoilage, which lowers the market value and acceptability of these fish products. Beyond pre-harvest and post-harvest, fish slaughtering procedures must be welfare-friendly and stress-free to maintain the texture, colour and appearance of the fish. It is interesting to note that the majority of fish slaughtering techniques have reportedly been found to be inhumane, which has a negative impact on the quality of fish products. Therefore, humane treatment and slaughter of fish products during pre- and post-harvest activities contribute significantly to increasing fish productivity, enhancing livelihood opportunities for fish farmers, boosting return on investment, reducing societal malnutrition and achieving fish sustainability along with higher foreign exchange earnings.