Evaluation of physical and instrumentally determined sensory attributes of Atlantic salmon portions packaged in modified atmosphere and vacuum skin

Authors: Sherry Stephanie Chan, Maren Skare, Bjørn Tore Rotabakk, Morten Sivertsvik, Jørgen Lerfall, Trond Løvdal, Bjørn Roth
Published in: Lebensmittel-Wissenschaft und-Technologie, 00236438, 2021, ISSN 0023-6438
Publisher: Academic Press
DOI: 10.1016/j.lwt.2021.111404

Abstract

Fresh Atlantic salmon (Salmo salar) were slaughtered and stored on ice at 0 °C then portioned and packaged six to eight days later in modified atmosphere (CO₂:N₂ 60:40) packaging (MAP), vacuum skin packaging and open air. All fillet portions were stored in refrigerated conditions at 4 °C. Physical and instrumentally determined sensory quality parameters, including water holding properties, pH, colour, texture and microbiological shelf life, were examined for three weeks. The results showed that both MAP and vacuum skin packaging gave comparable quality in drip loss, water holding capacity, texture and microbiological shelf life. Both packaging groups displayed increased lightness and decreased redness and yellowness throughout storage after filleting. Fillets kept in MAP had consistently lower pH with a darker, more reddish, and yellowish colour than skin packaged fillets. Fillets stored in air had the shortest microbiological shelf life (<13 days) even when they were portioned later. It is concluded that the microbiological shelf life of MAP and skin packaged fillets at 4 °C was around 18–20 days with a limit of 10⁶ cfu/g and therefore effectively extends the microbiological shelf life of raw fillets by 1.5 times. Read more here…

Atlantic Salmon (Salmo salar) Performance Fed Low Trophic Ingredients in a Fish Meal and Fish Oil Free Diet

Authors: K. Kousoulaki, L. Sveen, F. Norén and Å. Espmark
Published in: Frontiers in physiology, 2022, ISSN 1664-042X
Publisher: Frontiers Research Foundation
DOI: 10.3389/fphys.2022.884740

Abstract

To evolve fish farming in an eco-efficient way, feed production must become less dependent on forage fish-based ingredients and make more use of low trophic level organisms, including microalgae, higher plants, as filter feeding organisms and other ingredients with low competition to established food value chains. Diets nearly free of fish meal and fish oil are not a novelty but are often composed of complex mixtures, containing supplements to meet the farmed animal’s nutritional requirements. Sustaining a growing aquaculture production, maintaining at the same time fish health, welfare, and profitability, and meeting strict environmental and food safety demands, is challenging and requires new technologies, great investments, and more knowledge. A benchmarking feeding trial was performed to demonstrate the main effects of four low trophic raw materials on Atlantic salmon (Salmo salar) growth, metabolism, skin health and fillet quality. To this end, a diet was produced to contain commercially relevant levels of fresh high quality organic FM and FO and was used as a control in the trial (FMFO). Heterotrophically produced Schizochytrium limacinum biomass was used to replace organic FO (HM diet). Spray dried cell wall disrupted biomass of the phototrophically cultured diatom Phaeodactylum tricornutum replaced partly FM and FO (PM diet). Black soldier fly (Hermetia illucens) larvae meal and tunicate (Ciona intestinalis) meal, were used to produce the diets BSFL and TM, respectively, replacing large parts of FM as compared to the FMFO. A fifth test diet was produced combining all test raw materials and removing all FM and FO (0FM0FO diet). All test ingredients were well accepted sustaining high growth rates (TGC values near 4) and feed efficiency (FCR values below 0.9) in salmon showing good gut health and normal metabolic responses. However, none of the treatments reached the growth performance of FMFO. Additional differences between test and control treatments were identified in dietary nutrient apparent digestibility, fish biometrics, blood metabolites and fillet and skin composition. Extensive raw material and dietary chemical characterisation was performed to provide insight on potential shortcomings in the novel low trophic level ingredients which can possibly be overcome combining complementary raw materials. Read more here…

Using telemetry sensors mapping the energetic costs in European sea bass (Dicentrarchus labrax), as a tool for welfare remote monitoring in aquaculture 

Authors: Sébastien Alfonso, Walter Zupa, Maria Teresa Spedicato, Giuseppe Lembo, Pierluigi Carbonara
Published in: Frontiers in Animal Science, 2022, ISSN 2673-6225
Publisher: Frontiers Media S.A.
DOI: 10.3389/fanim.2022.885850

Abstract

Physiological real-time monitoring could help to prevent health and welfare issues in farmed fishes. Among physiological features that can be of interest for such purposes, there is the metabolic rate. Its measurement remains, however, difficult to be implemented in the field. Thus, mapping the fish acceleration recorded by tag with the oxygen consumption rate (MO2) could be promising to counter those limitations and to be used as a proxy for energy expenditure in the aquaculture environments. In this study, we investigated the swimming performance (Ucrit) and the swimming efficiency (Uopt, COTmin), and we estimated the metabolic traits (standard and maximum metabolic rates, SMR and MMR, as well the absolute aerobic scope, AS) of European sea bass (Dicentrarchus labrax; n = 90) in swimming tunnel. Among all tested fish, 40 fishes were implanted with an acoustic transmitter to correlate the acceleration recorded by the sensor with the MO2. In this study, the mean SMR, MMR, and AS values displayed by sea bass were 89.8, 579.2, and 489.4 mgO2 kg−1 h−1, respectively. The Uopt and COTmin estimated for sea bass were on average 1.94 km h−1 and 113.91 mgO2 kg−1 h−1, respectively. Overall, implantation of the sensor did not alter fish swimming performance or induced particular stress, able to increase MO2 or decrease swimming efficiency in tagged fish. Finally, acceleration recorded by tag has been successfully correlated with MO2 and fish mass using a sigmoid function (R2 = 0.88). Overall, such results would help for real-time monitoring of European sea bass health or welfare in the aquaculture environment in a framework of precision livestock farming. Read more here…

Workshop: How outputs from EU projects can upgrade health management in Mediterranean aquaculture 

Authors: S. Zrnčić, F. Padros, S. Tavornapanich, N. Lorenzen, D. Volpai, I. Mladineo, A.Manfrin, A. Sitjà-Bobadilla, E. Brun
Published in: Bulletin- European Association of Fish Pathologists, 2022, Page(s) 41(5):178, ISSN 0108-0288
Publisher: FRS Marine Lab.
DOI: 10.48045/001c.35854

Abstract

Aquaculture of European sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) is an essential activity in the Mediterranean basin. Several EU Horizon 2020 and regional projects are focusing on the improvement of their farming performance. This workshop aimed at displaying, sharing and discussing projects’ achievements among interested colleagues engaged to work with fish diseases. The most innovative research outputs aiming to improve the European mariculture were presented during this workshop, including updates from EU Horizon 2020 projects MedAID, PerformFISH, ParaFishControl, FutureEUAqua and the Italy-Croatia Interreg project AdriAquaNet. Read more here…

FutureEUAqua – FUTURE GROWTH IN SUSTAINABLE, RESILIENT AND CLIMATE FRIENDLY ORGANIC AND CONVENTIONAL EUROPEAN AQUACULTURE

by Åsa Maria Espmark

Presented at AE2019 conference in Berlin, Germany 2019

European aquaculture production has reached 1.25 million tonnes of seafood annually, with a value of over 4 billion euro. Of this amount, 4% is certified as organic, amounting in 2015 to a total of approximately 50,000 tonnes (EUMOFA, 2017). In 2015, EU consumers spent 54 billion euro for buying fisheries and aquaculture products, reaching the highest amount ever recorded (EUMOFA, 2017). Nevertheless, Europe is still heavily dependent on external markets to cover this demand. The increased demand for aquaculture products has to be covered at the same time as food production need to be more sustainable, climate friendly and supporting the UN Sustainable goals. The newly started EU project FutureEUAqua aims to effectively promote sustainable growth in aquaculture that is resilient to climate changes, and environmental friendly organic and conventional aquaculture of major fish species in Europe. It is a well-documented assumption that aquaculture that will meet future challenges with respect to the growing consumer demand for high quality, nutritious and responsibly produced food. FutureEUAqua will promote innovations in the whole value chain, including genetic selection, ingredients and feeds, non-invasive monitoring technologies, innovative fish products and packaging methods, optimal production systems such as IMTA and RAS, taking into account socioeconomic considerations by the participation of a wide spectrum of stakeholders, training and dissemination activities. To achieve these ambiguous goals, 32 partners from R&D, industry and associations, originating from nine countries will collaborate in research, training, dissemination and contact with stakeholders through e.g. stakeholder events. FutureEUAqua will contribute with innovations that will arrive Technology readiness level (TRL) ranging from five to nine. Innovations will result from all research topics, including sustainable genotypes, feeds and farming management solutions; smart tools to monitor the farming environment that guarantee aquatic animal health and welfare, tailor-made aquaculture fresh/processed foods and packaging, IT tools and information packages to improve consumer’s awareness about aquaculture products and related markets.

 The results and innovations will have impacts by improving resilience and sustainability of aquaculture farming systems and practices. The results will have impact on a diversity of end users representing the whole value chain from breeding companies to processing plants and intelligent packaging, including e.g. digital farming solutions for improved animal health and welfare, retailers and customer care providers. We intend to gather stakeholders to contribute to the professional skills and competences of those working and being trained to work within the blue economy and support the implementation of the EU Common Fisheries Policy (CFP) and contribute to policymaking in research, innovation and technology.

POWER CALCULATIONS FOR OPTIMISATION OF THE EXPERIMENTAL DESIGN TO DETECT G X E: SALMON EXPERIMENTS IN FUTUREEUAQUA

by A. Kettunen and M. Lillehammer

Presented at AE2019 conference in Berlin, Germany 2019

Introduction
The objective of the WP1 in FutureEUAqua is to assess how the current breeding programmes for salmon, seabass, seabream and rainbow trout can respond to future demands for novel feed compositions, and to make further improvements to disease resistance, climate resilience and animal welfare. For Atlantic salmon (Salmo salar) we estimate the genotype by diet/climate interactions (GxE) in semi-commercial salmon production system and validate best selection methods in salmon breeding programs by comparing traditional BLUP selection with GS/MAS for production and robustness traits. Estimated correlations will be taken as indicators of the magnitude of re-ranking of genotypes across diets/environments. Power calculations are elementary part of the experimental design but unfortunately often de-prioritized, compromising the critical interpretation of the results. A priori power calculations of genetic studies are characterized with multiple uncertainties, such as true relationship structure, number of families and individuals at the time of registration and unknown heritability of the traits of interest. This said, we argue that by performing a range of power calculations it is possible to frame the true power of the experiment and improve the probability of executing scientifically solid experiments with given restrictions of resources. We demonstrate the optimisation of the experimental design in order to have adequate power to detect significant GxE (diet/climate aggregate) given FutureEUAqua WP1 resources. Read more on page 681 here…

THE ROLE OF INTERNET OF THINGS FOR HEALTHY FISH AND ENVIRONMENT IN THE EUROPEAN AQUACULTURE

Giuseppe Lembo*, Pierluigi Carbonara, Sebastien Alfonso, Walter Zupa, Maria Teresa Spedicato

Presented at the AE2019 conference in Berlin, Germany 2019

Introduction

The overall objective of the project FutureEUAqua is to promote sustainable growth of environmental friendly organic and conventional aquaculture to meet future challenges of the growing consumer demand for high quality, nutritious and responsibly produced food. In WP5 of the FutureEUAqua project we are committed to develop and test a multiplatform tracking system for simultaneously monitoring the activity and physiology of fish, as well as the main parameters of the environment where they are farmed, by using a wireless communication system. The study of aquatic animals (e.g. fish behaviour, condition, physiology) and the farming environment presents unique challenges to scientists because of the physical characteristics of water. However, scientific studies and efforts have increasingly turned to the use of electronic sensors, which have enhanced our knowledge on the performances of the farmed fish and the impacts on the surrounding aquatic system. In their most basic form, electronic sensors and tags may include radio or acoustic beacons transmitting signals, which can bring specific codes to identify animals, and allow them to be tracked using receivers that detect the transmitted signals (Hazen et al. 2012). Basic archival tags must be, instead, physically recovered in order to obtain the data. Because the strength of radio signals rapidly attenuate in seawater, acoustic transmissions is preferred for fish tracking in marine environment (Lembo et al., 2002), while radio transmission is commonly used in freshwater environment. More advanced tags incorporate sensors that measure and record a suite of environmental and/or biological parameters of fish (Cooke et al. 2016). Simple biomass estimators and logging stations, installed on the feeding barge and/or on the cages, can give full control over all water parameters and provide the information required to monitor/expand the production. Flexible sensors systems are conceived to log oxygen, temperature, salinity, sea current, pH, wind and CO2. In addition, sensor and camera systems may provide also information for estimating the biomass in the cages and developing reliable fish feeding strategies. Indeed, electronic sensors are significantly improving our understanding of fish behaviour and are emerging as key sources of information for improving aquaculture management practices. The wireless communication system to monitor the large scale demonstration activities foreseen in the project FutureEUAqua will both facilitate effective study design and replication, increasing the accuracy of data standardization, processing and interpretation (e.g., Huveneers et al. 2016), providing industry with the information needed to facilitate health/welfare and optimal management practices. Read more here (pages 779-780)…

EFFECTS OF NOVEL INGREDIENTS ON GROWTH PERFORMANCE IN EUROPEAN SEA BASS, Dicentrarchus labrax

A. Vasilaki, K. Kousoulaki , T.A. Samuelsen , G. Pyrenis , D. Kogiannou , K. Grigorakis , E. Fountoulaki , E. Mente and I. Nengas

Presented at the AE2019 conference Berlin, Germany 2019

Introduction
Limited availability of ingredients in aquaculture feeds is crucial in order to maintain the increasing demands of aquaculture industry Gamboa‐Delgado & Márquez‐Reyes 2018). However, to safeguard sustainable exploitation of natural resources, the use of capture fisheries-based fishmeal and fish oil needs to be reduced in conventional fish feeds (Tacon & Metian, 2015). Accordingly, sources with high quality protein and essential nutrients are imperative need otherwise fish performance (Kousoulaki et al., 2012), health status and final product quality (Kousoulaki et al., 2016) may be jeopardized when substituting dietary fish meal by alternative ingredients of lower nutritional value. The main objective of this study is to test ingredients and design formulations for commercially relevant tailored-made aqua feeds, ensuring high performance, maintaining, or enhancing nutritional value and environmental friendliness. Read more here (pages 1571-1572)…

Effective algorithmic operational framework for fish texture evaluation in industry: Achieving maturity

Authors: Dimitrios Dimogianopoulos; Kriton Grigorakis
Published in: Aquaculture and Fisheries, 1, 2020, ISSN 2468-550X
Publisher: Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.
DOI: 10.1016/j.aaf.2020.10.001

Abstract
Reliable, nondestructive fish freshness evaluation applicable during fish commercialization has been continuously pursued by scientists and industry. Taking into account that fish texture is primarily affected even at early stages of post-mortem storage, a relevant nondestructive testing framework for rapid textural assessment of fish freshness was developed in the past. Herein, an algorithm operating within the aforementioned framework and optimized for use in industrial environments is proposed. Sea bass (Dicentrarchus labrax) both freshly killed and stored on ice for 6 days have been used for comparative testing. The fish is part of a system, which is vibration-tested via a new testing protocol designed for easy implementation and robustness to noise. At the same time, a new closed-form analytical expression for the system response to the specific testing is computed and used along with experimental data, for obtaining specific mechanical (thus muscle-structural) characteristics of fish flesh. This computation is designed to only require readily available routines found in most relevant software. The algorithmic operational framework has been used in two different test setups (a custom-built test rig and a prototype device), with results following remarkably similar trends, clearly discriminating different textural (thus freshness) characteristics, and consequently validating the proposed approach. Read more here…

The combined effect of pulsed electric field treatment and brine salting on changes in the oxidative stability of lipids and proteins and color characteristics of sea bass (Dicentrarchus labrax)

Authors: Janna Cropotova; Silvia Tappi; Jessica Genovese; Pietro Rocculi; Marco Dalla Rosa; Turid Rustad
Published in: Heliyon, Vol 7, Iss 1, Pp e05947- (2021), 1, 2021, ISSN 2405-8440
Publisher: Londen: Elsevier Ltd.
DOI: 10.1016/j.heliyon.2021.e05947

Abstract
A combined effect of pulsed electric field application and salting in a brine with 5 and 10% w/w NaCl on oxidative stability of lipids and proteins, as well as color characteristics of sea bass samples, was assessed in the study. The applied intensity of the current was set at 10 and 20 A corresponding to 300 and 600 V cm−1, respectively. Pulsed electric field (PEF) treatment led to a significant (p < 0.05) increase in primary and secondary lipid oxidation products expressed as peroxide value, conjugated dienes and 2-thiobarbituric acid reactive substances in PEF-treated samples compared to untreated ones. Conjugated dienes, as unstable primary oxidation products, correlated with b∗-value (p < 0.05, R = 0.789), suggesting their contribution to the yellowness of the fish flesh due to fast decomposition and conversion into secondary oxidation products yielding yellow pigmentation.
However, none of the fish samples treated at the higher current intensity of 20 A exceeded the acceptable level of 5 meq active oxygen/kg lipid according to the requirements of the Standard for fish oils CODEX STAN 329–2017, suggesting acceptable oxidative status quality of sea bass samples after the treatment. PEF-treated fish samples also showed a significant increase in Schiff bases and total carbonyls on day 5 and day 8 of brine salting compared to non-treated samples, revealing a strong effect of electroporation on protein oxidation. Read more here…

GENETIC VARIATION FOR CLIMATE CHANGE RESILIENCE IN GROWTH OF ATLANTIC SALMON

Authors: B.S. Dagnachew, I. Thorland, B. Hillestad & A. Kettunen
Published in: Aquaculture europe 20 Abstacts, 2021, Page(s) 140-141
Publisher: European Aquaculture Society

Introduction

The presence genetic by environment interaction (GxE) tells that strains respond differently to changes in environmental/climate parameters. Existence of such variation may hinder the optimal realization of genetic gain and affects the competitiveness of aquaculture industry. However, estimates of GxE are lacking for many economically important traits (Sae-Lim et al, 2016), and need to be assessed to enable optimization of breeding programs towards development of robust genetic material for future conditions. Climate changes and increased water temperature may cause higher risk for certain disease outbreaks in aquaculture (Towers, 2015, Khaw et al., 2019), and consequently selective breeding for better robustness is of interest. The aim of this work is to assess the genetic variation for climate resilience in growth traits in A. salmon. Read more here on page 140-141…

Link to video

GROWTH PERFORMANCE OF GILTHEAD SEABREAM (Sparus aurata) FED LOW FISHMEAL ORGANIC DIETS

Author(s): A. Tampou1, S. Andreopoulou, I. Nengas, A. Vasilaki, Ι.Τ. Κarapanagiotidis, E. Mente
Published in: Aquaculture Europe 21 Abstracts, 2021, Page(s) 1267-1268
Publisher: European Aquaculture Society

Introduction

Organic aquaculture seems to be a very well promising sector in the global ecology and economy (FiBL & IFOAM, 2020). Organic aquaculture reflects a specific production approach driven by the growing public interest in sustainable utilization of resources (Mente et al., 2011, 2012, 2019; Lembo & Mente, 2019). In the context of sustainability, the search for ingredients that are characterized by low FIFO ratios is of much interest. The aim of this study is to examine the growth performance of sea bream (Sparus aurata) fed diets with a low FIFO mix of ingredients for organic aquaculture. Read more here…

MARKER ASSISTED SELECTION FOR RESISTANCE AGAINST VIRAL NERVOUS NECROSIS IN EUROPEAN SEABASS (Dicentrarchus labrax)

Author(s): M. L. Aslam, S. Vela-Avitúa, V. Bakopoulos, K. Papanna, L. Kottaras, A. Dimitroglou, L. Papaharisis, C. S. Tsigenopoulos, I. Thorland
Published in: Aquaculture Europe 21 Abstracts, 2021, Page(s) 81-82
Publisher: European Aquaculture Society

Introduction

Contagious diseases are a major threat in aquaculture due to losses caused by high mortalities and the reduced growth of surviving fish. Viral nervous necrosis (VNN) is an infectious disease caused by nervous necrosis virus (NNV, red-spotted grouper nervous necrosis virus, RGNNV in European sea bass) which is considered a serious concern for European seabass producers, with fry and juveniles being highly susceptible. The outbreak of VNN may cause up to 100% mortalities at larval and around 20% mortalities at advanced juvenile stages[1, 2]. Moreover, the surviving fish present poor growth rate and ultimately high economic losses for the producers.

Selection and breeding for resistance against infectious diseases is highly effective tool to prevent and/or diminish disease outbreaks. Currently available advanced selection methods with the application of genomic/marker(s) information could pace up response to selection. The genetic variation for resistance against VNN obtained from the challenge tested population was presented previously [3]. The aim of current study was to further look into the genomic architecture of the
trait and explore potential of marker assisted and/or genomic selection and obtain realized validation of QTL effects. Read more here on page 81-82…

PERFORMANCE OF NOVEL LOW TROPHIC RAW MATERIALS IN ATLANTIC SALMON (Salmo salar) DIETS

Authors: K. Kousoulaki, T. Larsson and L. Sveen
Published in: Aquaculture Europe 21 Abstracts, 2021, Page(s) 661-662
Publisher: European Aquaculture Society

Introduction

Many different raw materials are considered as candidates for replacing fish meal (FM) and fish oil FO) in diets for salmonids, particularly focusing on locally produced low trophic level organisms with higher sustainability and circular economy potential. However, most of these novel raw materials differ from fish , containing e.g., high levels of complex carbohydrates or fully saturated triglycerides, and their nutritional value and nutrient bioavailability must be investigated before their use in commercial feeds. Read more here…

GROWTH PERFORMANCE OF GILTHEAD SEABREAM (Sparus aurata) FED LOW FISHMEAL DIETS WITH INNOVATIVE INGREDIENTS

Author(s): Α. Tampou, S. Andreopoulou, Ι. Νengas, Κ. Kousoulaki, Α. Vasilaki, E. Mente
Published in: Aquaculture Europe 20 Abstracts, 2020, Page(s) 566-567
Publisher: European Aquaculture Society

Introduction

The constant demand of sea products forces the global fisheries and aquaculture to produce more. Aquaculture of carnivorous species rely on marine protein and oil, but during 2018, 18 million tons of wild fish have used for the production fishmeal and fish oil (FAO, 2020). This, nowadays, has led most of the research to focus on the replacement of fishmeal and fish oil with sustainable sources of protein and lipids. This study aims to evaluate the effect of dietary fishmeal replacement with alternative ingredients such as algae meal, insect meal and tunicate meal on growth performance of gilthead sea bream (Sparus aurata). Read more here…

Mapping the Energetic Costs of Free-Swimming Gilthead Sea Bream (Sparus aurata), a Key Species in European Marine Aquaculture

Authors: Sébastien Alfonso, Walter Zupa, Maria Teresa Spedicato, Giuseppe Lembo and Pierluigi Carbonara
Published in: Biology, 20797737, 2021, ISSN 2079-7737
Publisher: MDPI
DOI: 10.3390/biology10121357

Simple Summary

Assessment of the energetic costs of different living activities is of primary interest among fish biologists. However, assessing energy expenditure in free-swimming fish is challenging owing to the difficulty of performing such measurements in the field. Therefore, the use of implant fish with sensors that transmit signals that serve as a proxy for energy expenditure is a promising method to counter these limitations, allowing remote monitoring in tagged fish. The aim of this study was to correlate the acceleration recorded by the tag with the activities of the red and white muscles and the oxygen consumption rate (MO2), which could serve as a proxy for energy expenditure, in gilthead sea bream (Sparus aurata), a key species in European marine aquaculture. The acceleration recorded by the tag was successfully correlated with MO2. Additionally, through electromyographic analyses, we determined the activities of the red and white muscles, which are indicative of the contributions of aerobic and anaerobic metabolisms during swimming. Finally, the tag implantation did not affect the swimming performance, metabolic traits, and swimming efficiency of the sea bream. By obtaining insights into both aerobic and anaerobic metabolisms, sensor mapping with physiological indicators may be useful for the purposes of aquaculture health/welfare remote monitoring of gilthead sea bream.

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Study of the influence of pulsed electric field pre-treatment on quality parameters of sea bass during brine salting

Authors: Cropotova, J., Tappi, S., Genovese, J., Rocculi, P., Laghi, L., Dalla Rosa, M., & Rustad, T.
Published in: Innovative Food Science & Emerging Technologies, 2021, ISSN 1466-8564
Publisher: Elsevier BV
DOI: 10.1016/j.ifset.2021.102706

Absract

Pulsed electric field (PEF), as an emerging technique, has recently gained increased popularity in food processing and preservation. However, applications in the seafood industry are still scarce. In the present study, sea bass samples were subjected to PEF pre-treatment prior to brine salting to verify the possible acceleration of the brining rate, increasing the salt uptake and ensuring the homogeneous salt distribution in the muscle. The applied intensity of the current was set at 10 and 20 A (corresponding to a field strength of 0.3 and 0.6 kV/cm) prior to sea bass salting in brine with 5 and 10% salt concentration, respectively. The results have shown that PEF pretreatment could effectively shorten the brine salting time compared to control samples (from 5 to 2 days), or increase the salt uptake up to 77%, ensuring at the same time its homogenous distribution in the muscle. However, myofibrillar protein solubility was significantly reduced in PEF pretreated samples. At the same time, no significant differences in water holding capacity and water activity between PEF pre-treated and untreated samples were found during the whole salting period. Freezable water was influenced by PEF application, but the effect was significant only at the lowest salt concentration during the first period of the salting process.

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