Comparison of Quality Changes in Eurasian Perch (Perca fluviatilis L.) Fillets Originated from Two Different Rearing Systems during Frozen and Refrigerated Storage.

Nima Hematyar,Marketa Prokesova,Jan Mraz,Frantisek Vacha,Vlastimil Stejskal,Martin Krizek,Hanne Søndergård Møller,Eva Dadakova,Sabine Sampels,Zuzana Linhartová,Trine Kastrup Dalsgaard

doi:10.3390/foods10061405

Abstract

The current knowledge on how different Eurasian perch rearing systems impact the final fillet quality is scant. Therefore, two domestic storage conditions were investigated—10 months frozen (−20 °C) and 12 days refrigerated (+4 °C) storage conditions—in order to determine (i) how the choice of rearing system affects fillets quality during different processing conditions and (ii) if oxidative changes and other quality parameters were interactive. For the proposed idea, proteome analysis, oxidative changes, and some quality parameters were considered in this study. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicated a higher loss of protein in the frozen fillets from ponds (PF) than the fillets from recirculating aquaculture systems (RAS) (RF). Western blot showed a higher protein carbonyls level in RF compared to PF, which was confirmed by the total protein carbonyls during frozen storage. PF indicated less liquid loss, hardness, and oxidation progress than RF in both storage conditions. The biogenic amines index (BAI) in the fillets from either origin showed acceptable levels during storage at +4 °C. Furthermore, the n-3/n-6 ratio was similar for both fillets. The deterioration of fillets during frozen storage was mainly caused by formation of ice crystals followed by protein oxidation, while protein oxidation was the main concern during refrigerated storage confirmed by principal component analysis (PCA) analysis.

Highlights

The production of Eurasian perch (Perca fluviatilis L.) in aquaculture was 585 tons in 2016 [1]
In line with our results, [8,36] reported a significantly higher amount of mono-unsaturated fatty acids (MUFA) in the fillet from cultivated pike perch and intensive farmed perch compared to fillets from a pond system and higher levels of polyunsaturated fatty acids (PUFA) in wild perch compared to the cultivated perch
This study indicated an impact of rearing conditions on fish fillet quality and the progress of lipid and protein oxidation during short- and long-term storage

Summary

Introduction

The production of Eurasian perch (Perca fluviatilis L.) in aquaculture was 585 tons in 2016 [1] (https://www.fishbase.in/search.php, accessed on 12 June 2021). Due to the high market price of Eurasian perch (Perca fluviatilis L.) fillet, it is considered a valuable commercial fish species [2]. Through the last two decades, recirculating aquaculture systems (RAS) have been expanded for different of European inland aquaculture [3]. In this rearing system, stable temperature (23 ◦ C), uniform photoperiod (12L:12D), high stocking density (up to 60 kg m-3), and commercially formulated feeds are used [4]. Fish reared in ponds with fluctuating temperatures have different growth rates and they grow on more natural feed like zooplankton and chironomids, which are responsible for different colors in fish fillets [6]

Methods

Discussion

Conclusion