Tag: Quality

Reports

Effects of additives and different salting methods on the utilization and quality of farmed cod products / Effects of additives and different salting methods on yield and quality of farmed cod products

Published:

01/11/2011

Authors:

Kristín Anna Þórarinsdóttir, Aðalheiður Ólafsdóttir, Kolbrún Sveinsdóttir, Ásbjörn Jónsson, Hannes Magnússon, Kristján G. Jóakimsson, Sveinn K. Guðjónsson

Supported by:

AVS (R 11 006‐010)

Contact

Aðalheiður Ólafsdóttir

Sensory evaluation manager

adalheiduro@matis.is

Effects of additives and different salting methods on the utilization and quality of farmed cod products / Effects of additives and different salting methods on yield and quality of farmed cod products

The aim of the experiments was to examine the effect of salting methods and brine composition on the utilization and quality of products processed from farmed cod before freezing to death. Fillets were either injected or injected and pickled. The brine was of different salinity, in addition to which the use of polyphosphate and a mixture of citrate and ascorbate was examined. Changes in utilization, water content, water resistance and quality were monitored over a 9-month period in frost. The results of the project show that it is possible to increase salt uptake and weight changes of fillets by changing processing processes even though the fish has not died of freezing. There was a definite difference in efficacy symptoms in the first 3 months depending on whether the fillets were only injected or injected and pickled. With longer storage, the difference between the groups decreased. At the beginning of storage, factors that characterize fresh products were prominent, but as the storage period progressed, factors such as cold storage odor, freezing taste, craving and tableware odor became more prominent. The use of phosphate and a mixture of citrate and ascorbate appeared to be able to reduce the development to some extent according to the results for TBARS, but the effect was not found in color measurements or sensory evaluation. 

The aim of experiments was to investigate the effects of different salting methods and brine composition on yield and quality of products, processed from pre ‐ rigor farmed cod. Fillets were either injected or injected and brined. Different brine concentrations were used, as well as polyphosphates and a mixture of citrate and ascorbate. Changes in yield, water content, water retention and quality of the products were followed over 9 months period of frozen storage. Results show that it is possible to increase the salt uptake and weight changes of the fillets by altering processing procedures for the pre ‐ rigor fish. The curing characteristics of the products depended on salting methods, ie if the fillets were only injected or injected and brine salted before freezing, especially during the first 3 months. Longer storage time reduced the difference between the groups. At the beginning of the storage, freshness characteristics were strong but during storage attributes like frozen odor and taste, rancid taste and dish cloth odor become predominant. Oxidation was reduced by use of phosphate and the mixture of citrate and ascorbate, as indicated by lower TBARS ‐ values. However, the effect was neither detected in results from color measurements nor sensory analysis.

Report closed until 01.01.2015

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Reports

Quality of coastal fishing catches 2011

Published:

15/09/2011

Authors:

Jónas R. Viðarsson, Sigurjón Arason, Sveinn Margeirsson, Guðjón Gunnarsson, Garðar Sverrisson, Örn Sævar Holm, Þórhallur Ottesen

Supported by:

Ministry of Fisheries and Agriculture

Contact

Jónas Rúnar Viðarsson

Director of Business and Development

jonas@matis.is

Quality of coastal fishing catches 2011

At the end of the summer, the Ministry of Fisheries and Agriculture requested from Matís, Matvælastofnun and the Directorate of Fisheries that an assessment be made of the quality of coastal fishing catches. Matvælastofnun had already, in collaboration with the Directorate of Fisheries, launched an effort that dealt with catch treatment in general for all day-trip boats and that work was used in the project. A steering group was formed for the project and it decided that the focus would mainly be on a few principles that affect product quality, ie. icing and cooling, worms in the flesh, size and classification, bleeding and gutting, sorting and finishing in pots, color of redness and procedures in fish markets. Measurements and other data collection took place in June, July and August. Data were collected as follows:

• The Directorate of Fisheries and MAST measured the temperature of the catch when landing around the country.

• The fish markets increased the temperature measurements in their catch and provided the results with the project.

• MAST employees investigated various issues related to the handling of catch among small boat fishermen.

• Matís' employee interviewed the parties that handle the catch of coastal fishing boats the most.

• Matís employees visited the fish market to check procedures.

The results of the survey show that inshore fish vary in quality. Coastal fishing boats fish during the hottest season when fish are in poor condition for natural reasons, they tend to stay close to land where the fish are small, there are more worms and the color of the red is darker (kelp); they usually land uncut catches and the size distribution is large. Access to ice is limited in some ports, gutting services are generally no longer available and the transport of ungutted catch between parts of the country at this time of year can be detrimental to the raw material if the catch treatment has not been satisfactory. Ensuring the quality of the catch is therefore a problem for the coastal fishing fleet. The most influential factor in the quality of inshore fishing is cooling. In general, it can be said that the coastal fishing fleet performs well in comparison with the traditional day-trip boats in terms of cooling, and it is not possible to distinguish a significant difference between these fishing groups. The results of the audit also indicate that the cooling of coastal catches has improved from the previous year. It should be noted, however, that cooling needs to be further improved to meet the requirements set out in regulations. Classification and gutting are also factors that affect the quality of coastal fishing catches. It is important that fish markets and their customers find acceptable ways to ensure that buyers are given the size of fish they consider to be buying, but the authorities will need to consider changes to regulations on gutting to ensure the maximum quality of inshore catches. With regard to other factors influencing quality, it is most natural for market laws to prevail, ie. that price and quality go hand in hand, but in order for that to happen, it is necessary to increase the visibility of quality factors in the fish markets and increase promotion. Efforts were made to educate, measure and monitor day-trippers in the summer of 2011 and it is important that the government ensures that this path is continued next year.

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Reports

Addition of collagen to heavy salted and lightly salted, chilled and frozen cod fillets

Published:

01/05/2011

Authors:

Kristín Anna Þórarinsdóttir, Hannes Magnússon, Irek Klonowski, Ásbjörn Jónsson, Frank Hansen, Egil Olsen, Sigurjón Arason

Supported by:

NORA

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Addition of collagen to heavy salted and lightly salted, chilled and frozen cod fillets

The effect of added gelatin extracted from fish was investigated on the utilization, chemical composition and quality of chilled, frozen and salted cod fillets. The gelatin was mixed into brine which was then injected into the fillets. Salted fillets were pickled after injection, then salted dry for 3 weeks and finally dehydrated. For comparison, fillets were sprayed only with brine. The main results were that the effect of gelatin on utilization and chemical composition was insignificant. Changes were mainly due to increased salt content. Another issue was the damage processes in chilled products. Microbial growth and degradation formation were higher in the fillets injected with gelatin. However, no visual difference in fillet appearance could be detected by brine composition. 

The effects of added fish gelatin on yield, chemical composition and quality of chilled, frozen and salted cod fillets were evaluated. The gelatin was mixed with salt brine and injected to the fillets. Salted fillets were brined after injection, dry salted for 3 weeks and finally rehydrated. Fillets injected only with salt brine were used as control. Effects of added gelatin on yield and chemical composition were not significant. Alterations were primarily due to the increased salt content by injection. Conversely, the growth of microorganisms and degradation within chilled fillets was accelerated by addition of gelatin. However, no significant differences were observed in visual appearance of the fillets. 

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Reports

Small vessels - Optimizing catch value

Published:

01/12/2010

Authors:

Jónas R. Viðarsson, Sveinn Margeirsson, Sigurjón Arason

Supported by:

AVS (project R 011‐09)

Contact

Jónas Rúnar Viðarsson

Director of Business and Development

jonas@matis.is

Small vessels - Optimizing catch value

The catch of small boats has the potential to be the best raw material available, as it is hardly possible to think of a fresher fish than the catch of day-trippers fishing on line or hand gear. Improper handling can, however, have the effect that small-boat fish do not live up to the expectations placed on them, which in turn means that it is not possible to process the catch into the most valuable products. Often, however, relatively small changes in working methods are required to ensure that the catch is under the brand name as a fish of maximum quality. This report discusses the issues that most affect the quality and shelf life of small boat fish, measures and comparisons are made of various influencing factors, reports on the preparation of guidance and incentive material published in connection with the project, and finally proposals are made for improvements in the value chain of small boat fish. The main emphasis in the project was on the preparation and distribution of teaching and instructional material for seafarers. A booklet and leaflets were published and distributed to all small boat fishermen in the country, and it is expected that the result will be reflected in increased knowledge of the importance of good handling of fish. Interested parties can contact Matís and receive the brochure by post, but it is also available on the company's website, ie. www.matis.is/media/matis/utgafa/Mikilvaegi‐godrar‐medhondlunar‐a‐fiski.pdf

The catch of small day ‐ boats using handline or longline has the potentials of being the best available raw material for the production of high value seafood. Improper handling has however often resulted in poor quality of this catch, which makes the products unsuitable for high ‐ end markets. Generally speaking there is however only need for relatively small adjustments in handling procedures in order to allow fish from small day ‐ boats to live up to its potentials as top quality seafood. In this report are discussed various quality issues related to small day ‐ boats. Measurements and comparisons are made between quality factors. Work related to writing, publishing and distribution of an educational brochure and other quality inducing material is accounted for. And finally there are brought forth suggestions on how to improve the value chain of catch from small day‐ boats. The main focus of this project was awarded to publishing practical and easy to understand educational material for fishermen. A brochure and a one ‐ pager were published and distributed to every small vessel in the Icelandic fleet. Hopefully, this educational material will be widely used amongst fishermen and contribute to improved knowledge on the importance of proper handling of seafood. The brochure is available at Matís and online at www.matis.is/media/matis/utgafa/Mikilvaegi‐godrar‐medhondlunar‐a‐fiski.pdf

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Reports

Overview on fish quality research - Impact of fish handling, processing, storage and logistics on fish quality deterioration

Published:

01/11/2010

Authors:

Hélène L. Lauzon, Björn Margeirsson, Kolbrún Sveinsdóttir, María Guðjónsdóttir, Magnea G. Karlsdóttir, Emilia Martinsdóttir

Supported by:

AVS R&D Fund of Ministry of Fisheries in Iceland, Technology Development Fund and EU IP Chill-on (contract FP6-016333-2)

Contact

Kolbrún Sveinsdóttir

Project Manager

kolbrun.sveinsdottir@matis.is

Overview on fish quality research - Impact of fish handling, processing, storage and logistics on fish quality deterioration

The short shelf life of fish is a limiting factor in the export of fresh fish products from Iceland. The initial quality of raw materials, methods of cooling, processing, packaging and conditions during storage and transport are discussed, as well as the effects of all these factors on the freshness and shelf life of fish products. Temperature control is very important to maintain the quality of the fish. Pre-processed fillets have been used to lower the pre-packing temperature. However, care must be taken that the pre-cooling technology does not endanger the microbial condition of the product and thus causes it to be damaged earlier after packaging. The synergistic effects of supercooling and aerated packaging (MAP) can significantly extend the freshness period and shelf life of fish products. Furthermore, packaging methods are examined, including new, more environmentally friendly packaging. Finally, the effect of transport routes of fresh fish products on their final quality to consumers in the market is discussed. This report provides an overview of the research of the Fisheries Research Institute and Matís ohf over the past three decades on the subject. Furthermore, it is discussed how these results can benefit the fishing industry.

The limited shelf life of fresh fish products is a large hurdle for the export of fresh products from Iceland. The influence of raw material quality, cooling methods, processing, packaging and storage conditions on freshness and shelf life extension is discussed. Temperature control is important to maintain fish quality. Pre-cooling of fillets in process has been used to lower the temperature prior to packaging. However, the cooling technique applied should not compromise the microbiological quality of the product and render it vulnerable to faster spoilage postpackaging. Synergism of combined superchilling and modified atmosphere packaging (MAP) can lead to a considerable extension of the freshness period and shelf life of fish products. Further, alternative and environmentally-friendly packaging methods are considered. Finally, the impact of transportation mode of fresh fish products on their resulting quality is examined. This report provides an overview of the findings on fish research carried out at Matís (Icelandic Fisheries Laboratories) over the last three decades and further discusses their practicality for the fish processing industry.

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Reports

The effect of different cooling techniques on the quality changes and shelf life of whole cod (Gadus morhua)

Published:

01/08/2010

Authors:

Hannes Magnússon, Kolbrún Sveinsdóttir, Lárus Þorvaldsson, María Guðjónsdóttir, Hélène L. Lauzon, Eyjólfur Reynisson, Árni R. Rúnarsson, Sveinn H. Magnússon, Jónas R. Viðarsson, Sigurjón Arason, Emilia Martinsdóttir

Supported by:

AVS R&D Fund of Ministry of Fisheries in Iceland, the Technology Development Fund at the Icelandic Center for Research and EU (contract FP6-016333-2)

Contact

Kolbrún Sveinsdóttir

Project Manager

kolbrun.sveinsdottir@matis.is

The effect of different cooling techniques on the quality changes and shelf life of whole cod (Gadus morhua)

The purpose of the experiment was to investigate the effect of three different cooling methods on the shelf life of whole, gutted cod: (i) Cooling with crushed plate ice, (ii) cooling with liquid ice, (iii) pre-cooling with liquid ice and then cooling with crushed plate ice. Temperature processes were monitored with temperature sensors in all groups during the storage period. Samples were assessed by sensory evaluation, microbial and chemical measurements during the 10 days the fish was stored. The results of microbial and chemical measurements were generally in good agreement with the results of sensory evaluation. Comparison of experimental groups revealed that cod chilled with liquid ice had a shelf life of about two to three days shorter than the other two groups. The shelf life of the cod was considerably shorter than various previous studies have shown, especially in the group that was cooled with liquid ice (only 9-10 days). It is now clear that the cod that was cooled with liquid ice was vanished on board the fishing vessel compared to the other two groups. In addition, refrigerated storage after landing was not as good as might be considered, but the temperature fluctuated between 2-5 ° C. This could possibly explain the shorter shelf life of all groups compared to previous studies.

The aim of this experiment was to investigate the effect of three different cooling methods on the storage quality of whole, bled gutted cod: (i) Cooled with crushed plate ice, (ii) cooled with liquid ice, (iii) pre-cooled in liquid ice and then cooled with crushed plate ice. The temperature history of each group was studied using temperature loggers. The samples were analyzed with sensory, microbiological and chemical methods for up to 10 days from catch. The results from microbial and chemical measurements were generally in good agreement with the results from sensory evaluation. Comparison of the groups showed that the use of liquid ice instead of plate ice resulted in two to three days shorter shelf life than in the other two groups. The shelf life in this study was considerably shorter compared to previous studies with whole cod, especially in the experimental group where liquid ice was used for cooling (only 9-10 days). It is now known that the liquid iced group in this experiment was insufficiently iced on board the fishing vessel compared to the other two groups. Additionally, the ambient temperature in the cold room of the fish plant was relatively high and fluctuated between 2 - 5 ° C during the storage period. This could possibly explain the shorter shelf life of all groups compared to some earlier studies.

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Reports

Supply chain of Icelandic containerized fish to the UK / Supply chain of Icelandic containerized fish to the UK

Published:

01/04/2010

Authors:

Jónas R. Viðarsson, Sveinn Margeirsson

Supported by:

AVS

Contact

Jónas Rúnar Viðarsson

Director of Business and Development

jonas@matis.is

Supply chain of Icelandic containerized fish to the UK / Supply chain of Icelandic containerized fish to the UK

This report describes the progress and results of the project "value chain of Icelandic container fish to the UK" funded by the ACP Fund. The aim of the project is to promote improvements in the value chain of container fish with the aim of increasing the quality and value of the products. In the first part of the project, a statistical assessment is made of whether the price and quality of container fish go hand in hand, but the results from that analysis indicate that supply has a dominant effect on fish prices and that the effect of quality is completely overshadowed. One of the main preconditions for encouraging improvements in the container fish value chain is that it can be shown that increased quality has financial benefits. Therefore, attempts were made to increase the provision of information on the forthcoming supply, in addition to which the information that accompanied catches was added to the floor of the auction markets. This was done in the hope that it would boost buyers' awareness of quality and that it would have a positive effect on fish prices. However, this experiment did not yield the desired results. It is the project partner's opinion that the key to increasing the quality and value of container fish is to arouse more interest among sellers as well as buyers in quality. In this way, buyers will be more willing to pay a higher price for the best quality, thus creating a market-related incentive among sellers to deliver only the best possible quality. With this aim in mind, the project partners were responsible for the introduction of quality assessment in the classification of fish in the UK markets and it is hoped that this will be useful to buyers in identifying which exporters perform best. The website www.matis.is/gamafiskur was also launched, with the aim of disseminating information to everyone in the container fish value chain on the issues that are likely to affect quality and value.

This is a report on the progress and results from the project "supply chain of Icelandic containerized fish to the UK". The objective of the project is to contribute to improvements in the supply chain of containerized fish from Iceland with the aim to improve quality and value. Financial benefits are a necessary condition in order to motivate improvements in the supply chain of containerized fish. Experiments were therefore made where information on expected supply and labeling of bins at auction markets were improved. This however did not return the expected results ie it did not affect average prices. The key to increasing quality and value of Icelandic containerized fish is to raise awareness for quality amongst suppliers and processors. Processors need to identify the suppliers that are supplying the best fish and they also need to reward them with higher prices. This would create a market-based incentive for suppliers to supply only top-quality fish. In order to contribute to this an intake quality score system has been implemented at Fishgate and Grimsby Fish Market, collecting data on the performance of individual suppliers. Also, a web-based supply chain guide www.matis.is/supplychainguide has been published, where relevant information for each link in the supply chain will be gathered.

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Reports

Bacterial diversity in the processing environment of fish products

Published:

01/03/2010

Authors:

Eyjólfur Reynisson, Sveinn Haukur Magnússon, Árni Rafn Rúnarsson, Viggó Þór Marteinsson

Supported by:

Tækniþróunarsjóður, AVS

Contact

Viggó Marteinsson

Research Group Leader

viggo@matis.is

Bacterial diversity in the processing environment of fish products

The report seeks to address the diversity and species composition of micro-organisms in fish processing environments. The research work began with the installation and development of methods for scanning microbial composition using molecular biological methods, and then at a later stage, work began on examining selected environments from the fishing industry. Two fish processing plants were visited, each twice where an evaluation was made of the processing and approx. 20 samples taken in each trip. A diverse community of bacteria was found, where known harmful bacteria were usually in a high proportion along with various other species. Microbial counts showed high levels of bacteria on the surface of production lines during processing with few bacterial groups in excess but also numerous other species in smaller quantities. The main groups of bacteria found belong to Photobacterium phosphoreum, which was in the highest proportion overall throughout the study, along with Flavobacterium, Psychrobacter, Chryseobacter, Acinetobacter and Pseudoalteromonas. All of these species are known fish bacteria that live in the redness and intestines of live fish. This is the first known project where molecular biological methods are used to scan the bacterial ecosystem of fish processing plants. A knowledge base has therefore been laid here for bacterial ecosystems in different conditions in fish processing, which will be used permanently in research and development of improved processing processes and storage methods for fish.

In this report we seek answers on diversity and species composition of bacteria in fish processing environment. The study initiated method development to screen microbial systems using molecular methods followed by analysis of samples from 2 fish processing plants. This research shows the presence of a diverse microbial community in fish processing environment where known spoilage microorganisms are typically in high relative numbers along with various other bacterial species. Total viable counts showed the presence of bacteria in high numbers on processing surfaces during fish processing where few species typically dominated the community. Photobacterium phosphoreum was the most apparent species followed by genera such as Flavobacterium, Psychrobacter, Chryseobacter, Acinetobacter and Pseudoalteromonas. All these species are known fish associated bacteria that live on the skin and in the digestive tract of a living animal. To our knowledge, this is the first study where molecular methods are used to screen microbial communities in fish processing plants. This research has therefore contributed a database on bacterial diversity in fish processing plants that will be used in the future to improve processing and storage methods in the fish industry.

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Reports

24-hour detection of undesirable microbes in food / 24-hour detection of undesirable microbes in food

Published:

01/12/2009

Authors:

Eyjólfur Reynisson, Sveinn Haukur Magnússon, Árni Rafn Rúnarsson, Viggó Þór Marteinsson

Supported by:

Tækniþróunarsjóður, AVS

Contact

Viggó Marteinsson

Research Group Leader

viggo@matis.is

24-hour detection of undesirable microbes in food / 24-hour detection of undesirable microbes in food

The aim of the project was to develop and establish methods for rapid detection of undesirable bacteria in agricultural and marine products as well as other foods. With traditional methods as used today, results are obtained after 3 and up to 7 days, but with the methods developed in this project, it is possible to get results in a few hours or within 24 hours. The method is based on real-time PCR methodology and specific amplification of the genetic material of pathogenic bacteria and other undesirable bacteria. Diagnostic methods have been developed for major pathogens (Salmonella, Campylobacter, Listeria monocytogenes, Vibrio parahaemolyticus) in milk, meat and fish products as well as for specific spoilage bacteria in food. The results of the project will improve services to the food industry in Iceland by detecting unwanted microorganisms much earlier so that it is possible to intervene in production processes and thereby increase consumer safety in agricultural and fish products.

The aim of this project was to develop and set up new methods for rapid identification of undesirable bacteria in food and feed. With today's conventional and accredited culture methods results can be expected after 3 and up to 7 days. With the new methods to be taken in use and was developed in this project, the time of diagnostic procedure will decrease to few hours or to one working day. The detection methods are based on real ‐ time PCR technology and a specific amplification of genetic material of the undesired bacteria. Diagnostic methods for the most common pathogens (Salmonella, Campylobacter, Listeria monocytogenes, Vibrio parahaemolyticus) in meat‐, milk and fish products were developed through as well as quantitative assays for the main spoilage bacteria in fish. The results of the project will be used to improve the service for the Icelandic food industry on the domestic‐ and overseas markets by having rapid diagnostic methods for bacterial contamination at hand.

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Reports

Comparison of properties of farmed cod and wild cod in loose freezing / Effects of freezing on muscle properties of wild and farmed cod fillets

Published:

01/12/2008

Authors:

Valur Norðri Gunnlaugsson, María Guðjónsdóttir, Guðrún Anna Finnbogadóttir, Kristján Jóakimsson, Sigurjón Arason

Supported by:

AVS R26-06 / AVS R&D Fund of Ministry of Fisheries in Iceland

Contact

Valur Norðri Gunnlaugsson

Research Group Leader

valur.n.gunnlaugsson@matis.is

Comparison of properties of farmed cod and wild cod in loose freezing / Effects of freezing on muscle properties of wild and farmed cod fillets

A comparison was made of the effects of freezing on different cod fillets. The raw material was farmed pre rigor cod and wild pre and post rigor cod. It was also investigated how fillets sprayed with brine came out of the freezer. The results showed that freezing did not in any way reduce the quality of these products. They performed well in quality assessment, emissions did not increase in samples and there was little or no change in the chemical content of these samples. The products all came out well from the freezing, whether it was farmed fish or wild fish and what treatment he received during the slaughter process.

The research was part of the project "Processing and quality control of farmed cod, more specifically a summary for work component 6.

In this project phase the aim was to look at effect of freezing on cod fillets from wild and farmed cod in different rigor stages. The goal was also to evaluate effects of brine injecting on the quality of the product after freezing and thawing. The results indicated that the freezing process did not affect the quality of those products. The quality assessment and chemical measurements did not indicate negative changes during freezing and thawing. All the samples got good results, both farmed and wild cod samples and the brine injection did not affect the quality of frozen products.

Report closed until December 2011 / Report closed until December 2011

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