Reports

Desalting experiments

Published:

21/03/2024

Authors:

Cecile Dargentolle, Hildur Inga Sveinsdóttir, Sigurjón Arason and Kolbrún Sveinsdóttir

Supported by:

AVS Research Fund

Contact

Kolbrún Sveinsdóttir

Project Manager

kolbrun.sveinsdottir@matis.is

This report is closed. 

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Reports

Measurements of the characteristics of foal meat

Published:

03/07/2019

Authors:

Eva Margrét Jónudóttir, Guðjón Þorkelsson, Aðalheiður Ólafsdóttir, Óli Þór Hilmarsson, Kolbrún Sveinsdóttir

Supported by:

Agricultural Productivity Fund

Contact

Eva Margrét Jónudóttir

Project Manager

evamargret@matis.is

Measurements of the characteristics of foal meat

Domestic horsemeat sales are only about half of production, and while meat consumption is growing with increased economic growth, this does not apply to horsemeat. Horses are generally not bred specifically for meat production, but the meat is a by-product of equestrian breeding and drug production from mare's blood. The popularity of equestrianism and the production of medicines are unlikely to decline in the next few years, so there is every reason to make horsemeat high and thus prevent further marketing problems in the future. Horse meat has been in a marketing campaign abroad in recent months, especially in Asia, but information is lacking about its characteristics. The main goal of the project was to gather and disseminate information that supports and facilitates the way of marketing and sales of horsemeat. Products from three foals slaughtered on 03.12.18 were examined. Thermostat was placed in the refrigerator and in the innermost muscles of the body. Acid syringes were inserted into their spinal muscles after slaughter. All carcasses were deboned in the slaughterhouse at Hella and weighed according to the division into muscle, processing material, bones and fat. Each muscle was divided into 4 parts. The first was in color measurement, the second in chemical measurement, the third in sensory evaluation and the fourth in surgical measurement and measurement of southern shrinkage. In addition, samples were sent for analysis of bacterial counts as well as Listeria bacteria. It took about 17 hours for acidity to fall into the spinal muscles after slaughter and it took about 24 hours in the refrigerator after slaughter for the carcass to reach a perfect ambient temperature at 5 ° C. Measurements on cooked muscle confirm that foal meat is tender meat. Sequence of increasing surgical force (viscosity) is: Puffs <ball steak <arch muscle <hip stitch <thigh tongue <vertebral muscle <lump <outer thigh <brisket <inner thigh muscle. Southern atrophy during cooking was about 25%. Listeria moinocytogenes was never measured and all samples were below microbial criteria. Flavor was generally low or not measurable but increases proportionally more with increasing intramuscular fat as it lasts during storage. According to color measurements, foal meat is similarly light but slightly redder and yellower than lamb and there was a nuance difference between the muscles. After 14 days of storage, the meat became slightly redder / yellower. Muscles used as whole muscle by carcass are only 34.7% of total dead weight. The raw material is 28.9%, which tells us that the proportion of what is normally used by the drop weight is 63.6%. Horse meat has everything to offer in order to be sold as a high-quality meat product, and there should be nothing to prevent it from making better use of this valuable resource.

The main objective was to gather and disseminate information that will support marketing of equine meat. Meat and offals from three foals were analyzed. Temperature was monitored in chiller and carcasses after slaughter and pH loggers were placed in the loin muscle (m. Longissimus dorsi). Yield was measured by cutting the carcasses into muscles, triminngs, fat and bone the day after slaughter. Each muscle was cut into 4 parts.The first was used for measuring CIELAB L, a, b * color. The second was analyzed for nutritional value. The third was cooked and analyzed for sensory properties and the fourth cooked and analyzed for Warner Bratzler shear force and cooking loss. In addition, samples were submitted for analysis of bacterial numbers as well as Listeria bacteria. It took about 17 hours for the pH to drop in the loin muscles after slaughter and it took about 24 hours for the carcasses to reach chiller temperature of 5 ° C. Shear force analysis confirmed the tenderness of foal meat. Cooking loss was about 25%. Listeria monocytogenes was not detected, and all samples were within acceptable limits for microbial counts. Generally, rancid flavor was little or not detected but increased proportionally with increasing intramuscular fat and storage time. Foal meat is similar to or lighter but more reddish and yellow than lamb met and there are slight differences between muscles. After 14 days of storage, the meat became slightly redder / yellower. Whole muscles were only 34.7% of carcass weight. Meat trimmings were 28.9%. The total yield was therefore 63.5%. Foal meat is a high-quality meat product and there are opportunities to market as such, and also to develop new products from the trimmings.

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Reports

New technology to increase the value of catfish catches

Published:

01/07/2018

Authors:

Gunnar Þórðarson, Sigurjón Arason

Supported by:

AVS Fisheries Research Fund (R 025-11), Rannís

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

New technology to increase the value of catfish catches

The purpose of the project was to adapt processing to supercooled raw materials, to ensure the homogeneity of raw materials with the aim of improving product quality, increasing utilization and minimizing fillet defects. In the project, a new type of skinning machine was developed and then tested under real conditions. Comparison of supercooled and traditional (frozen) ingredients. Supercooled raw material is stiffer than conventional, and the same can be said for fillets cooled after filleting to ensure packing in fresh packages at low temperatures, preferably below 0 ° C. Traditional skinning machines have not been able to handle such raw material, but the new machine has already been put into use and is proving successful. A comparative experiment was carried out between super-chilled haddock that was six days old and traditional raw material from the same catch. Subsequently, a comparative study was conducted on cod, made from super-chilled and conventional raw materials. Utilization, fillet quality and defects were compared, as well as product division after cutting into fillet pieces, as well as temperature processes during processing in both groups. The results were very good for supercooled raw materials, both in terms of quality, utilization and temperature of products.

The purpose of the project was to customize processing of sub-chilled raw materials to ensure uniformity of raw materials with the aim of improving product quality, increasing utilization and minimizing fillet defects. A new skinning machine for demersal fish was designed and tested in this project, especially to work with sub-chilled raw material. Sub-chilled raw material is more rigid than traditional raw material and can withstand more handling and give better quality of the finished product. Sub-chilled raw material also provides lower product temperature in packed fresh fish production, at 0 ° C or even below it. Traditional skinning machines have not been able to handle sub-chilled fillets. A comparative experiment with six-day old haddock where sub-chilled raw material were compared with traditional one, from same catch, were processed. Built on that outcome a follow-up, a comparative study of cod was processed with sub-chilled and traditional raw material. In both experiments a comparison of yield, fillets quality, fillets defects and temperature throughout the production into final packaging were recorded. The results were excellent in favor of sub-chilled raw material, both in terms of quality, yield and temperature of products.

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Reports

Raw material process in shrimp factories

Published:

01/01/2013

Authors:

Gunnar Þórðarson, Albert Haraldsson, Albert Högnason, Ásbjörn Jónsson, Minh Van Nguyen, Sigurjón Arason

Supported by:

Westfjords Growth Agreement

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

Raw material process in shrimp factories

Shrimp processing has been very successful in improving the utilization of raw materials, and the utilization has decreased from 20% to over 40% in just over twenty years. The use of poly ‐ phosphate (PP) has been important in this process, but these substances have been used together with salt and citric acid as excipients in the pre-processing of the shrimp. Utilization has been the best in the processing of thawed raw materials, but utilization has been significantly poorer in fresh shrimp. In Kampa shrimp processing, fresh shrimp are divided into two main categories; deep-sea shrimp and deep-sea shrimp caught in Ísafjarðardjúpur or Arnarfjörður. Ocean prawns have given better utilization than deep-sea prawns, which in most cases are smaller. The main purpose of this project was to compare the activity of these substances on thawed and fresh shrimp to improve utilization for the latter category. A study was set up to measure weight gain with differently strong blends and different times on fresh shrimp. Three experiments were performed, the first with both deep-sea shrimp and deep-sea shrimp, and the second two with only deep-sea shrimp. Studies were conducted from October 2011 to June 2012. The results of these studies strongly indicated that the pickling time of fresh shrimp needed to be shortened compared to thawed, but a traditional mixture gave the best results. This project was to test snail equipment from 3X Technology, Rotex, and compare the result with the traditional Kampa method, with 660 l. kerum. A new and cheaper method was introduced before this part of the study was carried out and it was therefore decided to cancel that part of the project. Instead, it was decided to focus on chemical research into the uptake of PP substances and what effect this would have on utilization in shrimp processing. Extensive research was started, but its scope is more than enough for a small project like this. Further research is therefore needed to complete this project, but the results obtained from this project are a good basis for further research. The result of the project is improved utilization for pelleting of deep-sea shrimp and deep-sea shrimp, which yields approx. one percentage point during processing.

The shrimp industry has achieved great success in improving the utilization of raw materials with the yield going from about 20% to over 40% in just over twenty years. Use of polyphosphates (a „poly ‐ phosphate„ (PP)) has been important in this process, but these materials have been used along with salt and citric acid as an excipient in the preliminary raw material method for shrimp. Best result has been in processing defrosted (frozen raw material) material with lesser yield using fresh material (unfrozen raw material). Kampi shrimp factory are mainly using two types of fresh raw material, in ‐ fjord shrimp from Arnarfjordur and Isafjardardjup, and deep water shrimp from fresh ‐ fish trawler fishing north of Iceland. The in ‐ fjord shrimp is generally smaller than the deep ‐ water shrimp. The main purpose of this project was to find a way to gain yield in processing the fresh material, and to transfer success in processing the defrosted shrimp to the fresh material. To do so a different strength of ingredients in pre ‐ maturing fluid in raw material method was used along with different time of maturing. The effect of this experience was recorded. Three experiments were conducted, the first with both in ‐ fjord shrimp and deep water shrimp, but the latter two with deep water shrimp only. Studies were conducted from October 2011 to June 2012. Results of these studies strongly indicated that a shorter time should be used for fresh material to gain better yield, but traditional combination of ingredients for maturing blend gave the best result. The second objective of this project was to test Rodex equipment from 3X Technology for raw material processing and compare the results with the traditional method Kampi uses, with 660 l. tubs. Before the test was conducted a new and cheaper method was introduced to this market, making the Rotex equipment unrivaled in this business. The project management team then decided to cancel this part of the project and to focus instead on chemical absorption studies for PP materials and the impact it would have on the utilization of the shrimp. Extensive studies were begun, but their scope is more than can be accomplished in a small project like this one. An advanced project will be needed to complete this study but the attainment of this study is an important input for further research in this area. The yield in fresh shrimp processed in Kampi have improved for about two percentage points as a result of this project, by using different maturing method for the raw material.

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Reports

Lumpfish production in the Westfjords

Published:

15/01/2012

Authors:

Gunnar Þórðarson, Óskar Torfason

Supported by:

Westfjords Growth Agreement

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

Lumpfish production in the Westfjords

From the year 2012, it will be obligatory to bring all grayling catch ashore according to the new regulation of the Ministry of Fisheries, no. 1083/2010. The project "Grayling, value from underutilized raw materials" is intended to strengthen the economy in the Westfjords by developing the processing of grayling products for export. The most suitable methods must be found for handling the raw material on board boats, in land processing, during transport and storage. Revenues increase in coastal areas and the more so as more and more of the grayling's by-products are sold. It is important that product development takes place to maximize revenue. Utilization of by-products of grayling contributes to increased employment in the coastal areas of the Westfjords. The occupation is related to handling catches, gutting, cleaning, packing, freezing and transport. 

From the year 2012 it will be required to bring the whole lumpfish catch to shore, under a new regulation from the Minister of Fisheries and Agriculture, No. 1083/2010. The project "Lumpfish, the value of underutilized species" is intended to support economic activity in the West-fjords by developing processing methods for lumpfish export. The aim is also to find the most suitable methods for handling the raw material on board the fishing vessels, at the processing side, and through storage and transport. Income will increase at coastal areas by more product landed and more extra production and export. Further product development is important to maximize revenue. Utilization of lumpfish by‐products contributes to increased employment in West‐fjords costal areas. Jobs related to handling of catch, gutting, cleaning, packing, freezing and transportation.

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Reports

Effect of post ‐ slaughter time intervals on yield and quality of farmed cod

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

Effect of post ‐ slaughter time intervals on yield and quality of farmed cod

The purpose of the experiment was to investigate whether the waiting time (0, 2, 4 hours) from slaughter to processing had an effect on weight uptake during injection and the properties of frozen fillets. In addition, changes in thawed fillets during refrigerated storage were assessed. Changes in weight, chemical content, water resistance, microbial growth and levels of degradable substances were monitored, as well as the fillets were sensitized. For comparison, untreated fillets were used. Weight gain was greater as the waiting time became longer. Salting increased the water resistance of the fillets and reduced shrinkage during thawing and boiling compared to untreated fillets. The injected fillets were therefore also juicier. Higher water resistance of injected fillets is explained by the fact that a higher proportion of water was inside the muscle cells in the injected fillets, while the extracellular fluid was higher in untreated fillets and proportionally more water was loosely bound. The number of micro-organisms was higher in injected fillets, as expected, as the injection spreads micro-organisms throughout the muscle instead of being found only on the surface of the muscle after filleting. Damage symptoms therefore became more pronounced in injected fillets as the storage of thawed fillets progressed over a 2-week period, despite the fact that the fillets were not initially considered more relaxed. Desalination of salted fillets was higher according to TBA values, but its effect was not noticeable on sensory evaluation. Higher salt content was thought to increase the death stiffness of the injected fillets and give a rubberier and stiffer texture compared to untreated fillets. The appearance of injected fillets was poorer, they were a bit darker and more uneven than untreated fillets.

The aim of the experiment was to evaluate the effect of post ‐ slaughter time intervals on injection yield and characteristics of frozen cod fillets. In addition, to evaluate changes in thawed fillets during chilled storage. Weight gain by injection was higher as the waiting time was longer. Salting increased water retention during storage and cooking in comparison to untreated fillets. Therefore, the injected fillets were also juicier. The higher water retention of injected fillets was explained by a higher percentage of water within the muscle cells while the ration of intercellular fluid was higher in untreated fillets. Spoilage became more pronounced in injected fillets over 2 weeks of chilled storage of the fillets after thawing. Oxidation was higher in salted complex as expressed by higher TBARS ‐ values, but the effect was not observed in sensory analysis. Higher salt content seemed to increase rigor contraction in injected fillets and result in a more rubbery texture of the injected fillets, which were also slightly darker and more heterogeneous than untreated fillets.

Report closed until 01.01.2015

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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

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

Catfish. Catch, markets, utilization and chemical content / Atlantic wolffish. Icelandic catch volumes, markets, yield and chemical content

Published:

01/01/2010

Authors:

Kristín Anna Þórarinsdóttir

Catfish. Catch, markets, utilization and chemical content / Atlantic wolffish. Icelandic catch volumes, markets, yield and chemical content

The report is a brief overview of the state of the knowledge available today on the catch volume, life pattern, utilization and chemical content of catfish caught in Iceland. The Marine Research Institute has been working on research into the distribution and life pattern of catfish in the sea around Iceland. Statistics Iceland's statistics show developments in, among other things, fishing and the disposal of catfish catches. Knowledge of the variability in the processing properties and chemical content of the fish is limited and nothing was found about the stability of catfish products during storage. The research based on utilization and chemical content is based on older data from IFL (now Matís ohf) from around 1980. They show that, as with other species, the condition of the fish is highly dependent on the time of spawning and the time of year. What makes catfish different from more common species such as cod is that it loses teeth during spawning and guards its eggs which inhibits food acquisition.

This report is a broad literature review about catch volumes, reproduction, yield and chemical content of Atlantic wolffish caught in Icelandic waters. The Icelandic Marine Institute has investigated the distribution, growth, maturity and fecundity of the fish and the Icelandic Statistics collects and produces statistics on fish catch, manufactured products and exports. Information about the variability in yield and chemical content of wolffish are limited and knowledge about the stability and degradation process of wolffish products is limited.

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Reports

Injection and brining of tilapia fillets

Published:

01/12/2009

Authors:

Kristín Anna Þórarinsdóttir, Kolbrún Sveinsdóttir, Þóra Valsdóttir, Irek Klonowski, Aðalheiður Ólafsdóttir, Hannes Magnússon, Arnljótur Bjarki Bergsson, Ragnar Jóhannsson, Emilia Martinsdóttir

Supported by:

Tækniþróunarsjóður Rannís / Technology Development Fund, RANNIS - Icelandic Center for Research

Contact

Kolbrún Sveinsdóttir

Project Manager

kolbrun.sveinsdottir@matis.is

Injection and brining of tilapia fillets

The aim of the project was to investigate the effect of spraying and pickling on the utilization, shelf life and properties of tilapia fillets. Three product categories were produced: chilled products, frozen products (with insignificant changes in salt content) and lightly salted, frozen products. During the processing of chilled products, red fillets were injected with a weak brine (1% salt) containing a reduced cod base (2% brine protein). Lightly salted fillets were initially sprayed with 4% brine, then pickled overnight. Part of the fillet was frozen after pickling but a similar amount was injected with the protein solution after pickling. Utilization increased during spraying and pickling, there was a significant difference in weight changes in frozen fillets and lightly salted fillets due to differences in the salt content of these two product categories. The waterproofness of fillets was poorer after freezing than after storage in the refrigerator. The shelf life of products was short and possible reasons for this are discussed in the report. Microbial growth and degradation processes were largely independent of injection and brine.

The objective of the project was to study effect of injection and brining on the yield, storage life and characteristics of tilapia fillets. Three different product groups were produced: chilled. Frozen (with small salt changes) and lightly salted products. During processing of chilled products fillets with skin were injected with brine containing minced cod (2%) protein in brine. Lightly brined fillets were initially injected with 4% brine and then brined overnight. A part of the fillets was frozen after brining but similar part was injected with protein solution after brining. The yield increased with injection and brining, distinct difference was in the weight changes of frozen and lightly salted fillets because of the difference of the salt content of these two product groups. Water holding capacity of the frozen fillets was lower than for chilled fillets and the storage life was very short. Microbial growth was mostly not depending on the injection and brining.

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