Editorial: Improving fish from catch to the consumer: Post harvest handling, processing, packaging, transportation and storage

Theofania Tsironi

Agricultural University of Athens, Department of Food Science and Human Nutrition, Laboratory of Food Process Engineering, Iera Odos 75, Athens, 11855, Greece

Aquaculture is the fastest growing food producing sector, accounting for almost 50% of the animal protein consumed globally, with the expectation that it will rise to 65% by 2030, due to the increasing emphasis on fish products as important components of a healthy diet.However, EU production is stagnating with approximately 60–65% of European demand for fish products being imported (EUMOFA, 2021).The reason for this is complex and the sector faces a number of challenges.

Fish and seafood are perishable products with high commercial value if their shelf life could be extended by appropriate handling, processing and packaging methods (Tsironi et al., 2020; Tsironi & Taoukis, 2018).Another critical issue for fish consumption nowadays is the consideration of fish as a time-consuming meal, resulting in the development of convenient, ready-to-cook or ready-to-eat products based on fish and seafood (Corbo et al., 2009; Du et al., 2020).Microbial activity is the main spoilage factor that affects quality of fish and seafood during storage and limits shelf life (Gram & Huss, 1996).Spoilage begins immediately postmortem and for this reason, fresh fish and seafood must be chilled appropriately after catching and stored in ice to prevent quality deterioration, ensure safety and decrease postharvest losses.Conventional food preservation methods (i.e.marination, canning and salting) are used for microbial control and shelf life extension of fish and seafood.However, the consumer currently demands safe and high quality foods, more natural, with the minimum addition of preservatives, and at the same time nutritious and healthy.Mild processing methods have been introduced as alternatives to traditional treatment for foods, which may prolong shelf life without affecting food quality and sensory properties (Qian et al., 2018; Tsironi et al., 2019; Tsironi &Taoukis, 2017; Wu et al., 2017).Optimized packaging systems can nowadays incorporate IoT devices (e.g.sensors, RFID) to assist food packaging and transportation in real-time (Tsironi & Taoukis, 2018;Vanderroost et al., 2014; Ye et al., 2022).Sustainability is also affected by high levels of loss and this is one factor behind the elevated production and transport costs of this product category.Rapid quality control at any stage of the supply chain by novel, reliable techniques,coupled with validated predictive shelf life models is critical for effective operations and higher safety and quality level of fish and seafood (Lan et al., 2022; Tsironi et al., 2017).

A multidisciplinary approach in the research focusing on the farmed fish and seafood can address these challenges and increase the availability of high quality and safe fish and seafood, while establishing more diverse ways to process and market these products.The aim of this special issue is to provide a summary of the recent advances and challenges at the postharvest stages of fish and seafood, affecting the safety and quality of the final food products, towards a more resilient and sustainable aquaculture.

Rowan (2022) addresses key developments, trends, challenges and opportunities surrounding digital transformation of fisheries and aquaculture across the supply chain.This viewpoint article addresses how digital transformation can help support and meet expansion needs of the fisheries/aquaculture industries that includes exploiting and harnessing ICT, IoT, Cloud-edge computing, AI, machine learning, immersive technologies and blockchain.

Theodorou and Tzovenis (2021) develop a working framework for the shellfish aquaculture of Greece to be used as a tool by the sector’s decision makers to advance strategies for risk elimination or avoidance.The framework is supported by data sets regarding development, production, profits and losses, retrieved by surveys through distributed questionnaires or interviews during site-visits, as well as by collecting data from national and international authorities.

In the study by Ntzimani et al., (2021), slurry ice is introduced as an alternative cooling medium for fish during harvesting and transportation, to retain flesh quality and extend shelf life, compared with conventional flake ice, resulting in 2–6 days shelf life extension of whole sea bass stored at 0◦C based on microbial growth, proteolytic enzyme activities and sensory evaluation.

The hurdle technology principles were implemented on eel fillets by Giannakourou et al.(2020), by combining two mild preservation techniques, namely tissue impregnation with bioactive compounds, followed by a water activity reduction step (through osmotic dehydration in hypertonic solutions).Shelf life of treated eel fillets exhibit a 2 to 3-fold shelf life improvement at 4◦C in terms of microbial growth.

The effect of frozen storage on the quality of silver carp emulsion sausages from washed mince is evaluated by Rahmanifarah et al.(2021),as an approach to reduce the use of sodium nitrite, which is associated with health risks.Based on this study, sausages from washed minces show lower TVB-N and lipid oxidation compared to sausages from unwashed mince, but also lower sensory and consumer-liking properties,indicating that further research should focus on the development of new fish-based products and optimization of processing conditions.

Thomas et al.(2021) evaluate the effect of modified atmosphere packed gilthead seabream skin, gills and intestines bacterial microbiome.In this study, Next Generation Sequencing analysis is applied for the accurate identification of microbial taxa in different fish tissues,including also uncultivable organisms and those present at low levels,providing the systematic and detailed evaluation of the spoilage mechanism of packed fish products.

Taking into account that fish texture is primarily affected even at early stages of post-mortem storage, a nondestructive testing method for rapid textural assessment of fish freshness is introduced by Dimogianopoulos and Grigorakis (2020), in the form of an algorithmic operational framework, and optimized for use in industrial environments for European sea bass.

Updated knowledge regarding the biogenic amine content of fresh fish, cephalopods, crustaceans and shellfish, as well as cured, fermented,dried and packaged fishery products is provided by Arulkumar et al.(2021).In this study, the first results of the control strategies that are currently in the epicenter of research interest are also presented.

Theodorou et al.(2021) demonstrate the high nutritional profile of the pearl oyster, supporting its suitability as a potential new Mediterranean seafood source for human consumption, considering the seasonal variation of the product, meat yield and biochemical composition from specimens collected in western Aegean Sea.

Power et al.(2022) outlines how omics technologies can generate novel tools for integration into seafood processing and quality control.Deployment of omics for identification of potential microalgal products of relevance to seafood quality and safety is also considered.

A novel method is introduced by Jeyaprabha et al.(2022) in the feeding trail for freshwater fishOreochromis mossambicusfingerlings, fed with bio encapsulatedChironomuslarva withKappaphycus alvarezii(Rhodophyta-red seaweed) for improving the quality of the final product.

Special thanks to the authors and the reviewers for contributing to this endeavor, with a sincere hope that it will advance the scientific literature in the field of aquaculture and seafood industry.