Sigurjon Arason - Academia.edu (original) (raw)

Papers by Sigurjon Arason

Trends in Food Science & Technology, 2018

Background: The continuous high expectations on the world's fisheries to provide products for hum... more Background: The continuous high expectations on the world's fisheries to provide products for human consumption is leading to increased overexploitation of fishing stocks. This unsustainable exploitation desperately calls for other suitable resources that can relieve the pressure on the fisheries. The utilization of Calanus finmarchicus has been proposed as a suitable alternative. There is, however, still a question of both ecological and economical sustainability of such exploitation. Scope and approach: This review describes currently utilized marine resources, and compares the suitability of C. finmarchicus as a useful alternative for those resources. Additionally, the review describes the life history and chemical composition of C. finmarchicus. Current utilization of C. finmarchicus is also described, along with industrial methods used to derive various products from Calanus, as well as a discussion of other potential products from the resource. Key findings and conclusions: C. finmarchicus can potentially be considered an alternative marine resource as it has a unique lipid composition, is rich in antioxidants, and contains diverse enzymes. However, the question of sustainable catching remains unanswered and must be addressed before C. finmarchicus can be considered for utilization.

Freezing and frozen storage has proven to be an effective method to preserve and prolong the stor... more Freezing and frozen storage has proven to be an effective method to preserve and prolong the storage life of seafood products. Production of frozen products provides all year around product availability although the catching is seasonal. There are several factors that can affect the quality and stability of frozen fish products, including the state of the raw material, processing methods and storage conditions. The aim of the study was to explore how the physicochemical properties of frozen herring fillets are affected regarding the state of the raw material during processing as well as storage conditions. Atlantic herring was processed and frozen pre- and post-rigor and stored at stable (-25 °C) and abused storage conditions. To investigate the storage stability and physical properties of the fillets, thawing drip, cooking yield and colour were evaluated, as well as proximate composition, fatty acid composition, pH and lipid degradation of the light and the dark muscle. The study d...

Eitt meginmarkmið verkefnisins var að afla grunnupplýsinga um eiginleika íslensks harðfisks og að... more Eitt meginmarkmið verkefnisins var að afla grunnupplýsinga um eiginleika íslensks harðfisks og að upplýsingarnar yrðu opnar og þannig öllum harðfiskframleiðendum á Íslandi til hagsbóta. Megin niðurstaða verkefnisins er að harðfiskur er mjög ríkulegur próteingjafi með 80-85% próteininnihald. Amínósýrurnar voru maeldar og bornar saman við amínósýrur í eggjum. Niðurstaðan er að harðfiskprótein eru af miklum gaeðum. Þessar niðurstöður styðja við markaðssetningu á harðfiski sem baeði heilsusamlegum mat og þjóðlegum mat. Mikilvaegt er að skoða saltinnihald í harðfiski betur og reyna að minnka það til að auka hollustu harðfisks sérstaklega í inni-heitþurrkuðum harðfiski þar sem það var mun haerra en í öðrum harðfiski. Maelingar á snefilefnum leiddu í ljós að magn þeirra í harðfiski er vel innan marka miðað við ráðlagðan dagskammt (RDS) nema í selen. Magn þess í 100 g er á við þrefaldan ráðlagðan dagskammt. Það er þó ekki talið skaðlegt á nokkurn hátt.

The aim of the study was twofold. Firstly, to explore the influence of time and temperature durin... more The aim of the study was twofold. Firstly, to explore the influence of time and temperature during frozen storage on lipid deterioration of red fish. That was done by comparing the effect of temperature fluctuation and abuse during frozen storage, as can be expected during transportation, on the physicochemical characteristics and lipid stability of redfish fillets. Secondly, to investigate the effect of 4 days postcatch and 9 days postcatch, and seasonal variation on the quality and storage stability of frozen red fish. Storage temperature and storage time affected the physical- and chemical properties in redfish, e.g free fatty acids, TBARS and TVB-N. Season of capture affected both the nutritional value and stability of golden redfish. The light muscle of fish caught in November was richer in EPA and DHA than in the fish caught in June. The fish caught in November was also more unstable through frozen storage, due to a more unsaturated nature of the fatty acids present, indicatin...

The effects of seawater and slurry ice bleeding methods on the sensory, microbiological and chemi... more The effects of seawater and slurry ice bleeding methods on the sensory, microbiological and chemical quality changes of cod fillets during chilled storage were examined in this study. The results from sensory evaluation showed that slurry ice bleeding method prolonged the shelf life of cod fillets up to 13-14 days compared to 10-11 days for fish bled in seawater. Slurry ice bleeding method also led to a slower microbial growth and biochemical developments, resulting lower total plate count (TPC), H2S-producing bacteria count, total volatile basic nitrogen (TVB-N), trimethylamine (TMA), free fatty acid (FFA) content and higher phospholipid content (PL) compared to those of samples bled in seawater. The results of principle component analysis revealed that TPC, H2S-producing bacteria, TVB-N, TMA and FFA were in significant correlation. They were also in negative correlation with sensory evaluation (Torry score), PL and water holding capacity (WHC).

Ágrip á íslensku: Markmið verkefnisins var að þróa hraðvirka greiningaraðferð til að meta gaeði s... more Ágrip á íslensku: Markmið verkefnisins var að þróa hraðvirka greiningaraðferð til að meta gaeði salts sem notað er til saltfiskframleiðslu. Takmark verkefnisins var að lágmarka gulumyndun í saltfiski. Tilraunir með að nota þorskalýsi sem staðgönguefni til að meta þránun fitu af völdum málma sýndu lofandi niðurstöður og nauðsynlegt er að yfirfaera niðurstöður fyrir þorskalýsi yfir á þorskflök. Niðurstöður benda til þess að járn hafi meiri áhrif á þránun fitu en við kopar. Þránun maeldist í fitu við allt að 5 ppm járnstyrk í salti. Nauðsynlegt er að skoða áhrif kopars og járns á oxun próteins í fiski.

EFNISYFIRLIT 1 INTRODUCTION 2 MATERIALS AND METHODS 2.1 Measurement devices 2.2 Numerical heat tr... more EFNISYFIRLIT 1 INTRODUCTION 2 MATERIALS AND METHODS 2.1 Measurement devices 2.2 Numerical heat transfer modelling 3 RESULTS AND DISCUSSION 3.1 Temperature control in chill chains-air vs. sea transport 3.2 Precooling 3.3 Packaging

The designations employed and the presentation of material in this information product do not imp... more The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the author(s) and do not necessarily reflect the views or policies of FAO. The designations employed and the presentation of material in the map(s) do not imply the expression of any opinion whatsoever on the part of FAO concerning the legal or constitutional status of any country, territory or sea area, or concerning the delimitation of frontiers.

Food Chemistry, 2020

This study aimed to evaluate the shelf-life of mechanically filleted well-fed Atlantic mackerel d... more This study aimed to evaluate the shelf-life of mechanically filleted well-fed Atlantic mackerel during frozen storage at-25 °C and effect of treatment with antioxidants (sodium erythorbate and a polyphosphate mixture) and different antioxidant application methods (dipping, spraying and glazing). Both physicochemical measurements and sensory analysis were applied. Antioxidant treatments prolonged shelf-life of mackerel. Sensory analysis indicated that untreated fillets had a shelf-life of less than 2.5 months, while all antioxidant treated fillets exceeded that. The most effective treatment, dipping fillets into a sodium erythorbate solution, yielding a shelf-life of 15 months. Physicochemical methods used to evaluate degradation of lipids in the fillets were free fatty acids (FFA), lipid hydroperoxides (PV) and thiobarbituric acid reactive substances (TBARS). They did not correlate with sensory results and might therefore be a questionable choice for evaluation of oxidation and development of rancid flavour and odour in complex matrixes such as Atlantic mackerel.

International Journal of Refrigeration, 2021

Abstract Cooling experiments using flake ice and chilled brine/seawater were carried out on ungut... more Abstract Cooling experiments using flake ice and chilled brine/seawater were carried out on ungutted and gutted cod. Core temperatures of the fish loins and tails were measured during the cooling process. The study aims were to investigate different approaches to chilling gutted and ungutted whole fish and compare controlled brine chilling with traditional flake ice chilling. Experiments were conducted in controlled environment using fish in three weight categories, around 2.5, 4 and 9 kg. The experimental results were used as design parameters for newly developed onboard industrial chilling processes using different approaches to superchill whole gutted cod (slurry ice and refrigerated seawater/brine). Industrial chilling processes were evaluated by mapping temperature profiles onboard three wet-fish trawlers using different chilling systems and methods. Temperature measurements were then used to generate a model to estimate chilling time and the convective heat transfer coefficient between 2, 4 and 6 kg fish and cooling medium. The chilling time of equal weight fish from +8°C to 0°C proved to be 30-50% shorter with refrigerated brine chilling compared to flake ice chilling. The difference between chilling gutted and ungutted cod was apparent, as expected, due to a greater surface area between gutted fish and the cooling medium. The chilling time difference between gutted and ungutted fish was less with flake ice chilling than with refrigerated brine chilling. Comparison of the model results with onboard measurements indicate that the thermal conductivity of the fish is limiting to the energy transfer and efficiency of the onboard chilling systems rather than the heat transfer coefficient.

Processes, 2020

The study aimed to provide insight into the lipid quality of pelagic fishmeal and fish oil proces... more The study aimed to provide insight into the lipid quality of pelagic fishmeal and fish oil processing of mackerel and herring cut-offs, and the effect of temperature changes in the cooker (85–95 °C) during production. Samples were collected after each processing step at a traditional processing line where water and lipid content, free fatty acids (FFA), phospholipids (PL) and fatty acid composition (FAC) were measured. Results showed that the standard procedures at 90 °C included ineffective draining and concentration steps. Moreover, the solid streams entering the driers variated in chemical composition, suggesting that processing each stream separately could be beneficial for maintaining the lipid quality. The cooking temperature affected the lipid removal from the fishmeal processing, where lowering the temperature to 85 °C resulted in a lower lipid content of the final fishmeal, along with lower FFA and PL values. Hence, the fishmeal and fish oil factories could save energy by l...

Journal of the American Oil Chemists' Society, 2017

Packaging Technology and Science, 2020

Insulated food containers of different sizes are commonly used to preserve the quality of perisha... more Insulated food containers of different sizes are commonly used to preserve the quality of perishable fresh fish products during transport and storage. The aim of the study was to explore the effects of packaging solutions with various depths on the quality of iced and superchilled farmed Atlantic salmon (Salmo salar). Insulated containers of different depths (32, 42, and 60 cm) and 17-cm deep expanded polystyrene (EPS) boxes were used to simulate transport and storage of the fish. The fish quality was evaluated after 4, 10, and 14 days of storage, where measurements on drip loss, texture, cooking yield, sensory evaluation, water and lipid distribution, and characteristics analysis in the fish muscle by nuclear magnetic resonance (NMR) spectroscopy were performed. Increased container depth from 32 to 42 cm increased the drip loss of superchilled salmon from 2.4% to 3.1% after 10 days of storage at −1 C. Iced storage of salmon for 10 days in EPS boxes resulted in less drip loss (0.5%) compared with superchilled salmon (1.5%) stored in EPS. The NMR analysis, sensory evaluation, texture analysis, and cooking yield did not reveal any major differences between salmon stored in containers of different depths. Iced storage increased pressure marks as compared with non-iced, superchilled storage in insulated containers. The results indicate that transport of whole salmon in reusable insulated plastic containers with a depth of 60 cm is possible without major quality changes observed for up to 10 days.

Journal of Food Composition and Analysis, 2020

Fishmeal and oil have traditionally been used for aquaculture feed but are being replaced by chea... more Fishmeal and oil have traditionally been used for aquaculture feed but are being replaced by cheaper ingredients. Fish side-streams are now predominantly used in the production of fishmeal and oil and can account for up to 50 % of the raw material. However, due to the increased competition there is a need to look for alternative high-value products from marine side-streams. The aim of the study was to assess the suitability of zooplankton rich side-streams in a pelagic processing plant (side-stream after heading and gutting, and foam from processing water) for further processing, collected in the summers of 2016-2018, and to investigate the effect of catching variables on the chemical composition and lipid quality of these side-streams. The side-stream after heading and gutting was rich in the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), peaking late August, as well as in the monounsatured fatty acid cetoleic acid, C22:1n11. The foam collected from the processing water was rich in monosaturated fatty acids but low in longchain omega-3 fatty acids. Lipid quality was dependant on the length of the time from catching to processing, with longer time resulting in higher oxidation of lipids. Due to its high lipid content and beneficial fatty acid composition the zooplankton-rich side-stream after heading and gutting is a promising new source of the beforementioned fatty acids and can be recommended to be processed further for human consumption.

Journal of Food Processing and Preservation, 2018

Fish is highly perishable, and thus the cold-chain plays an important role in the global trade of... more Fish is highly perishable, and thus the cold-chain plays an important role in the global trade of fish products. Interruption of the cold-chain during transportation and storage can lead to quality loss and reduced shelf-life of frozen fish (Gormley, Walshe, Hussey, & Butler, 2002; Romotowska, Gudjonsdottir, Karlsdottir, Kristinsson, & Arason, 2017). Frozen fatty fish such as herring is recommended to be stored at temperatures below −24°C and under stable conditions (Johnson, Nicholson, Rogger, & Stroud, 1994). However, during transportation and storage, temperature fluctuations commonly occur (Gutiérrez, Oliveira, Melo, & Júnior, 2017) and the temperature sometimes goes up to −12°C, or even to −8°C due to unstable ambient conditions, the position of the fish in the freezer or container and the duration of transportation (Keller, 2006). Temperature fluctuations affect the ice crystal formation, growth and recrystallization processes and may change the product appearance over time (Gormley et al., 2002; Jiang & Lee, 2004). Furthermore, temperature fluctuations lead to an increase in the amount of unfrozen water in the product. This can be linked to increased physicochemical deterioration due to enzymatic activity and lipid oxidation (Romotowska et al., 2017).

Journal of Food Engineering, 2018

Influence of processing additives, packaging and storage conditions on the physicochemical stabil... more Influence of processing additives, packaging and storage conditions on the physicochemical stability of frozen Tra catfish (Pangasius hypophthalmus) fillets

Food Science & Nutrition, 2019

In some countries, fish is brined or partially boiled (blanching) in brine before drying to inact... more In some countries, fish is brined or partially boiled (blanching) in brine before drying to inactivate enzymes and inhibit growth of bacteria. While smoking is commonly conducted either by hot smoking or cold smoking method depending on fish species and type of products desired, smoking changes the appearance, taste, and odor of the product, in addition to increasing the shelf life (Cyprian et al., 2015). Earlier studies report fish muscle protein to be less stable than ones originating from mammals (Baylan et al., 2015; Poulter, Ledward, Godber, Hall, & Rowlands, 1985). Fish drying or smoking process is therefore believed to have a consequence on muscle protein solubility and aggregation, thereby affecting the protein structure in the intracellular and extracellular matrix (Nguyen,

Food Research International, 2019

Fast and non-destructive prediction of the quality characteristics of food products during frozen... more Fast and non-destructive prediction of the quality characteristics of food products during frozen storage are of great value both for the food industry and the consumers. The current study investigated the potential of using low field Nuclear Magnetic Resonance (NMR) along with multivariate chemometric methods to predict various important physicochemical quality parameters in Atlantic mackerel during frozen storage, as affected by season of catch, freezing method and temperature, as well as frozen storage duration. The obtained results clearly showed that transverse relaxation data obtained by low field NMR can be effectively used to simultaneously predict multiple quality characteristics of the mackerel fillets through storage, including water and lipid content, water holding capacity, lipid oxidation (peroxide value (PV), and thiobartituric reactive substances (TBARS)) and lipid hydrolysis (free fatty acids (FFA)) content within the muscle. The NMR data could furthermore be used to predict variations in the muscle due to season of catch, the frozen storage duration of the mackerel samples when all samples were used, and whether the fish had been headed and gutted or stored whole, which freezing equipment had been used, and the frozen storage temperature for mackerel samples caught at the end of July. Simplified monitoring and optimization of these quality parameters in frozen mackerel with a fast and nondestructive analytical technique like low field NMR is thus of great value for the fishing industry. processing. Romotowska, Karlsdóttir, Gudjónsdóttir, Kristinsson, and Arason (2016) showed that seasonal and geographical variation, as well various handling and processing treatments had a significant effect on the quality and stability of frozen mackerel, especially on the lipid composition and degradation processes. However, the use of conventional quality analysis methods for assessment of water and lipid content, water holding capacity (WHC), lipid oxidation and hydrolysis products are expensive to perform, are time consuming, and make use of dangerous organic solvents. Faster and safer alternative methods are thus needed to make the industry monitor these quality changes in a more effective way. Relaxation time measurements by low field Nuclear Magnetic Resonance (NMR) has shown to be an effective method to assess structural changes in muscle tissue as affected by choice of raw materials, handling and treatments. Earlier studies have found strong correlations between the relaxation time parameters to various