Tag: Chilling

Reports

Comparison of packing of fresh fish products in boxes and pots for export by ship / Packing of fresh fish products in boxes and tubs intended for sea transport

Published:

01/07/2016

Authors:

Magnea G. Karlsdóttir, Ásgeir Jónsson, Gunnar Þórðarson, Björn Margeirsson, Sigurjón Arason, Aðalheiður Ólafsdóttir, Þorsteinn Ingi Víglundsson

Supported by:

AVS Fisheries Research Fund (R 034‐14)

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

Comparison of packing of fresh fish products in boxes and pots for export by ship / Packing of fresh fish products in boxes and tubs intended for sea transport

The aim of the study was to find the best and most cost-effective method of packing fresh fish products for shipping with a view to maximizing the shelf life of a product, which is one of the key factors in the marketing of fresh fish products. Experiments were carried out with the transport of fresh fish products in containers with ice scrapers and compared with the transport in foam plastic boxes with regard to temperature control, product quality and transport costs. Different product groups were compared that were packed in different packaging and stored at different storage temperatures. The purpose of these experiments was to simulate the environmental conditions during the transport of fresh fish products, with a view to evaluating the effect of pre-cooling before packaging and packaging methods on the shelf life of the products. The results clearly indicate that refrigeration of products before packaging as well as low and stable storage temperatures are among the most important factors that increase the shelf life of fresh fish products. Different packaging solutions also affected the shelf life of fresh fish products, although the effect was not as decisive as the effect of temperature. The results indicate an increased likelihood of longer shelf life if fresh fish products are packed in tanks with sub-chilled sludge compared to traditional packaging in a foam plastic box with ice. To estimate the amount of ice scraper required to maintain an acceptable temperature, a heat transfer model was developed. An economic analysis of different packaging and transport was carried out in the project and this work shows significant savings with the use of tanks for transporting fresh fish products in comparison with foam plastic boxes. Pots can replace a foam plastic box to a considerable extent and be a cost-effective option for some companies. The economic analysis showed that larger parties could take advantage of this method, as they can fill entire containers for export. But the method is no less useful for smaller processes, which do not have the capacity to make large investments in equipment to ensure adequate cooling for the packaging of products for export of fresh raw materials. The results are a good contribution to discussions about fresh fish products in foreign markets.

The goal of the study was to find the best and most efficient method of packaging fresh fish for sea transport with the aim of maximizing the storage life of the product, which is a key element in the marketing of fresh fish. Experiments were made with the transport of fresh fish in tubs with slurry ice and compared with transport in expanded polystyrene boxes with regard to temperature control, product quality and shipping cost. Different product groups were compared, using different temperature conditions and packing methods to find the best outcome for fresh fish quality and storage life. Experimental results clearly indicate that the pre ‐ cooling for packaging and low and stable storage temperature play a major factor to maximize storage life of fresh fish products. Different packaging solutions are also a factor, though the effect was not as dramatic as the effects of temperature. The results indicate an increased likelihood of extended shelf life if fresh fish is packed in a tub with a slurry ice compared to traditional packaging in expanded polystyrene boxes with ice. In order to estimate the necessary amount of slurry ice to maintain acceptable temperature, a thermal model was developed. Economic analysis of different packaging and transport was also carried out and the results showed substantial savings with the use of tubs for the transport of fresh fish products in comparison with the styrofoam boxes.

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Reports

Effects of bleeding methods on the quality and storage life of cod and saithe products

Published:

01/02/2014

Authors:

Magnea G. Karlsdóttir, Nguyen Van Minh, Sigurjón Arason, Aðalheiður Ólafsdóttir, Paulina E. Romotowska, Arnjótur B. Bergsson, Stefán Björnsson

Supported by:

AVS (R 11 087‐11)

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Effects of bleeding methods on the quality and storage life of cod and saithe products

The aim of the project was to examine the effect of different bleeding methods on the quality and shelf life of different cod and saithe products. By identifying ideal conditions for bleeding, gutting and bleeding, it is possible to prevent product defects due to blood and at the same time increase the stability of the products in transport and storage. The fish were either bloodied in the hands and in the machine. Bleeding took place in slush or sea and the effects of different bleeding times were examined. The effect of waiting time on tires before bleeding was also assessed, as well as bleeding and gutting the fish in one step or two steps (gutting performed after bleeding). The products studied in this project were chilled and frozen cod and saithe products, as well as salted cod products. Of the variables studied in this project, their importance differed in terms of which fish species were involved and what the final product was. When comparing comparable sample groups of cod and saithe, it is seen that different conditions are suitable for each species. This supports the theory that it is probably not possible to transfer the best bleeding method of cod to saithe and vice versa. Bleeding time and type of bleeding agent (sludge vs. seawater) had a decisive effect on the stability of the cod and saithe products examined. Cod products, both chilled and frozen, from raw material soaked in sludge generally resulted in improved quality and stability compared to if soaked in seawater. In contrast to cod, the bleeding of saithe into the sea generally resulted in a stable end product. The way the fish were bled and gutted also had a decisive effect on the final products. In the case of frozen cod products, raw and gutted raw material in one step generally yielded a more stable product compared to raw material that was gutted after bleeding had occurred (two steps). Salted products, on the other hand, were much more stable in storage if the raw material was gutted after bleeding. Different results were also obtained for saithe depending on the final product involved. Bleeding and gutting of saithe in a machine had a positive effect on the shelf life of chilled products compared to if made by hand. Machine bleeding and gutting, on the other hand, resulted in a much more unstable product in the cold. The results of the project show that the effects of different bleeding methods are quite dependent on the raw material as well as the final product involved.

The main objective of the project was to study the effects of different bleeding methods on quality and storage life of various cod and saithe products. Products defects due to blood residues can be prevented by optimizing bleeding protocols, and hence increase the quality and storage life of the products. For this, fishes were either bled and gutted by hand or by machine. The bleeding (blood draining) was carried out with seawater or slurry ice, and the effects of different bleeding times in the tanks were also investigated. Moreover, the effects of waiting time (on deck) before bleeding, as well as the procedure of bleeding technique (bleeding and gutting in one procedure vs. gutting after blood draining) were investigated. The various products evaluated were chilled and frozen cod and saithe products, and salted cod products. The importance of the different parameters investigated in this project varied considerably with regard to fish species and the final products. Comparison of parallel treatments groups of cod and saithe demonstrated that optimum bleeding procedures are different for each species. Waiting time on deck and bleeding media (slurry ice vs. seawater) significantly affected the storage life of the cod and saithe products. Cod products, both chilled and frozen, from fish bled in slurry ice generally resulted in improved quality and storage life compared to fish bled in seawater. In contrast to cod, bleeding or saithe in seawater resulted however in more stable products. The procedure during bleeding and gutting also had great impact on the storage life of the various products studied. Shorter storage life of salted cod products was generally observed when the raw material was bled and gutted in one step compared to when gutting was performed after bleeding (two steps). Rather conflicting results were, however, observed for saithe and were depending on the type of final product. Bleeding and gutting of saithe by machine improved the storage life of chilled products compared to when the saithe was bled and gutted by hand. The machine procedure had, however, negative effects on the storage life of the frozen saithe products. Overall, the results of this project indicate that the effects of different bleeding methods are highly relative to fish species as well as the final product of interest.

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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

Muscle spoilage in Nephrops

Published:

01/09/2010

Authors:

Guðmundur H. Gunnarsson

Supported by:

AVS Research Fund and NORA

Muscle spoilage in Nephrops

The project worked with the lobster industry in Iceland to identify the causes and define solutions to reduce muscle necrosis in lobster. Such myocardial infarction had increased greatly in recent years for no apparent reason. Initially, it was thought that the probable cause of the muscular dystrophy was a Hematodinium infection in the strain, but such an infection has caused considerable shocks in the Scottish lobster strain. It was confirmed that there was no association between Hematodinium infection and myocardial infarction. Subsequently, the emphasis of the project had to be changed. Extensive morphological studies of lobster were able to link muscle necrosis to enzyme activity in lobster hepatopancrea. Based on these results, a solution was defined to reduce the incidence of myocardial infarction. With improved cooling and treatment with enzyme inhibitors, muscle lobster necrosis has been significantly reduced.

This project was carried out in close association with the Icelandic Nephrops fishing and processing industry. The aim was to define reasons and propose solutions to reduce muscle spoilage in Nephrops. Such muscle spoilage had increased significantly during the last few years without any know reason. The original hypothesis of the project was that there might be a correlation between infection of the parasite Hematodininum and muscle spoilage. Such parasitic infection has resulted in lower quality products in the Scottish Nephrops industry for the last decade. In the project it was confirmed that such infection is not the underlying factor for muscle spoilage. This resulted in a change of direction in the project. Based on morphological analysis of Nephrops it was observed that the muscle spoilage was correlated with enzyme activity in the hepatopancrea. Based on this observation it was possible to propose a code of practice to reduce the onset of muscle spoilage. The code of practice is based on improved chilling and use of enzyme inhibitor during the storage of the Nephrops from catch to frozen product.

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Reports

Processing and quality control of farmed cod

Published:

01/04/2009

Authors:

Kristín Anna Þórarinsdóttir, Valur Norðri Gunnlaugsson, 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

Processing and quality control of farmed cod

The report is a summary of the results of the project "" Processing and quality control of farmed cod "which was carried out in collaboration between HG and Matís. Ways were sought to develop traditional methods for the production of fresh, frozen and lightly salted products so that they could be used for farmed fish. The aim of the project was to provide products from farmed cod with valuable and varied products that met the quality requirements of the market. Processing of farmed cod must be carried out before death. Otherwise there is a risk that the formation will be so great that the products will in the worst case be unsaleable. Chilled and loose-frozen products are of comparable quality to products made from wild cod. However, the properties are not the same and this is reflected in the taste and texture properties, among other things. Wild cod is coarser and often juicier, but farmed cod has a more meaty and stuttering texture and is sweeter in taste. Processing for death solidification means that traditional salting processes for farmed fish cannot be used. In light salting, methods such as injection and prolongation of the pickling time can be used to reduce the negative effects of lethal stiffness on uptake during normal course of action. Salting and temperature conditions need to be very well controlled to minimize the risk of microbial growth as very low salinity is used in the production of lightly salted (2% salt) products.

This report summarizes the results from the project "Processing and quality control of farmed cod" where processing and salting methods for farmed cod were developed in co-operation of HG (HradfrystihusidGunnvor Ltd) and Matís ohf. The main difference in processing of farmed and wild cod is that farmed cod has to be processed before rigor mortis. Otherwise there is a high risk of gaping and quality defects in products that are not accepted by markets. Chilled and IQF products processed from pre-rigor farmed cod were of similar quality as products from wild cod. However, farmed cod products have different properties, they have a sweeter taste and more "meaty" and firmer texture than products from wild cod which are softer and juicier. Processing of farmed cod before rigor retards weight increase and salt uptake during light salting. The effects of rigor can be reduced using brine injection and increasing brining time from traditional processed for farmed cod. Salting conditions and temperature must be carefully controlled during the process to avoid microbial growth at the low salt levels used in production of light salted (2% NaCl) products.

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Reports

Effect of chilling on lamb tenderloin

Published:

01/01/2007

Authors:

Ásbjörn Jónsson, Óli Þór Hilmarsson, Valur Norðri Gunnlaugsson

Supported by:

Agricultural Contracts Executive Committee

Contact

Óli Þór Hilmarsson

Project Manager

oli.th.hilmarsson@matis.is

Effect of chilling on lamb tenderloin

In recent years, cooling in slaughterhouses has increased significantly. Therefore, cooling in meat is faster. The speed of cooling has a great influence on the quality of meat. The refrigeration must follow the process of freezing to death in such a way that the meat quality is as high as possible, and it is therefore important to control the refrigeration process. Too fast cooling or freezing of lamb shortly after slaughter can cause cooling in the meat and the result is stiffer meat. The main objective of the project was to study the texture properties (tenderness) in lamb meat at different refrigeration temperatures and time in the slaughterhouse. Temperature measurements were performed in dilka carcasses in the slaughterhouse of slaughterhouses at different air temperatures. Samples were taken from the vertebral body dilka carcasses after varying lengths of presence in the meat hall, and they were frozen. Texture measurements were then performed on the samples to assess the effect of cooling on the muscle. The results of this study showed that meat stored in a meat hall and frozen the same day (after 4-5 hours) was stiffer than meat that had a longer cooling time in a meat hall. The project was carried out by Matís employees and funded by the Agricultural Contracts Executive Committee.

In recent years chilling in abattoirs has increased significantly and, furthermore, chilling in meat has become more rapid. The chilling rate has great effects on the quality of meat. The chilling has to correlate with rigor mortis to gain the best quality of the meat. A too rapid chilling or freezing of the meat shortly after slaughtering will cause cold shortening in the meat and the result is tough meat. The main object of the project was to study the textural properties of lamb meat at different chilling conditions and time in abattoirs. Samples were taken from the M. longissimus after different storage in the chilling room, and frozen. Measurements of textural properties were performed on the samples to estimate the impact of chilling of the muscle. The results indicated that meat stored for a short time in the chilling room and then frozen the same day (after 4 -5 hours) was tougher than meat stored for longer time in the chilling room. The project was done by employees of Matís and sponsored by the Ministry of agriculture.

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