Microorganisms are part of our food. However, knowledge of which microorganisms are found in food and in the production environment is still limited. A recent study, in which Matís participated, has provided new insight into this subject. The results will contribute to a better understanding of the effect of microorganisms on various aspects of food, such as shelf life, safety, quality and taste.
The study was part of the European project MASTER, which brought together 29 partners from 14 countries. One of the goals of the project was to create a database of microorganisms in food by sequencing genetic material from 2533 samples taken from various foods and their production environment. Matís was in charge of studying samples from Icelandic fish processing plants, but the research project covered all major food groups. This is the largest study ever conducted on the microbial composition of food and production environments, but a better understanding of these microbes could contribute to the improvement of people's health, as some microbes from food can become part of our microflora.
A total of 10899 food-associated microorganisms were identified in these samples, half of which were previously unknown species. The results showed that food-related microbes form an average of about 3% of the intestinal flora of adults and about 56% of the intestinal flora of infants.
"These results suggest that some of the microbes in our gut come directly from food, or that humans have historically acquired them from food, where they have later adapted and become part of the human gut flora," says Nicola Segata, a microbiologist at the University of Trento and the European Cancer Institute in Milan. Although 3% may seem like a low percentage, these microbes can have a major impact on the functioning of the intestinal flora. The database is therefore an important contribution to science and public health, as it will be useful for research on the effects of food-related microorganisms on our health.
Although few pathogenic microorganisms were identified in the food samples, there were several species that may be undesirable due to their effects on the taste or shelf life of foods. Knowledge of which microorganisms belong to certain foods can therefore be useful for producers, both large and small, to improve product quality. This information can also assist food control in defining which microorganisms should and should not be present in certain foods as well as tracking and certifying their origin. The results of the study were published last August 29 in the magazine Cell Press and the database is now accessible. Findings specifically related to seafood have also been published in the journal Heliyon, published by Cell Press. As mentioned above, the research is part of the European research project MASTER and was funded by Horizon 2020, Horizon Europe, the Italian Ministry of Foreign Affairs, the European Research Council, the Spanish Ministry of Science and Innovation, the Science Foundation of Ireland and the Irish Ministry of Agriculture, Food and Fisheries.
Anna Berg Samúelsdóttir, Matís, Alexandra Leeper, Sjávarklasinn, Clara Jégousse, Sjávarklasinn, Ólafur H. Friðjónsson, Matís, Elísabet Eik Guðmundsdóttir, Matís, Hörður Guðmundsson, Matís and Birgir Örn Smárason, Matís
Supported by:
Hringrásarsjóður
Contact
Anna Berg Samúelsdóttir
Project Manager
annab@matis.is
The main goal of the project "Microbes for the enrichment of aquaculture sludge" was to develop a method for treating side streams from aquaculture (sludge) with microorganisms so that the sludge can be used as fertilizer for agriculture.
Considering the rapid growth of aquaculture in Iceland, it is crucial for the sustainability of the industry to find solutions for side currents and thus strengthen the circular economy. The implementation of solutions that promote the use of side streams, and promote circulation, are in line with the United Nations' goals for sustainable development.
The legal framework for the use of fish farm sludge as fertilizer is both extensive and in parts quite complex, i.e. what is allowed and who grants permission. As an example of the requirements for using sludge as fertilizer, sludge must be applied to the pasture before December 1st if the area is to be used for grazing, animals can then be grazed on the area 5 months later or on April 1st at the earliest.
In the project, work was done to enrich nitrate in the sludge with microorganisms to increase the possibility of using the sludge as a fertilizer. An enrichment culture was established with the aim of enriching ammonia-oxidizing bacteria in the sludge. A chemical analysis of the sludge was also carried out to assess its nutrient content. The results of chemical measurements indicate that sludge can be ideal as a supplement or additive to, for example, biodegradable livestock manure. It is important to continue with a project that contributes to increasing the value of by-products such as sludge in order to keep nutrients within the circular economy. The use of sludge as fertilizer is beneficial for both aquaculture companies and Icelandic agriculture. _____
The primary objective of the project "Microorganisms for aquaculture sludge enrichment" was to develop a method for treating side streams from aquaculture (sludge) using microorganisms, thereby rendering the sludge suitable for use as agricultural fertilizer.
Given the rapid expansion of aquaculture in Iceland, finding solutions for side streams is imperative to sustain the industry and enhance circular economy practices. Implementing solutions that encourage side stream utilization aligns with the United Nations' sustainable development goals.
The legal landscape for utilizing fish farm sludge as fertilizer is extensive and, in certain aspects, complex, delineating what is permissible and who grants permission. For instance, applying sludge to pasture for grazing requires adherence to specific timelines, such as application before December 1st, with grazing permitted no earlier than 5 months later or on April 1st.
The project focused on enriching the sludge's nitrogen content with microorganisms. An enrichment culture was established to promote ammonia-oxidizing bacteria in the sludge, increasing its potential as a fertilizer. Chemical analysis of the sludge was conducted to evaluate its nutrient content. The results indicate that the sludge can serve as an ideal supplement or additive, for instance, with biodegradable livestock manure. Continuing projects that enhance the value of like sludge is crucial for maintaining nutrient cycles within the circular economy. The use of sludge as fertilizer is mutually beneficial for both aquaculture companies and Icelandic agriculture.
The sampling period covered by this report is from 1 November 2021 – 31 October 2022. A total of 108 samples were taken during the period, all for research within the Europlanet collaboration.
The development of Icelandic oat milk, protein powder from mackerel stream streams and value creation in algae processing are among the new projects of Matís and partners
Last week, Icelandic food producers and partners at Matís proved successful, with twelve projects that Matís received a grant from the Food Fund when the fund announced its first allocation. A few days earlier, Rannís had announced that a collaborative project led by Matís had received significant funding from the Market Plan for Social Challenges to work on the development of sustainable domestic fertilizers. There were also reports that the European Framework Program for Research and Innovation (H2020) had approved funding for projects in which Matís participates in the field of biotechnology. This great result clearly shows the strength and importance of Matís' collaboration with companies, institutions and entrepreneurs of all shapes and sizes, both domestically and abroad.
Matís' goal is to support research and innovation in the food and biotechnology industry, and these results show that collaboration with the company is a good option. Matís employs about 100 specialists in various fields when it comes to food production and biotechnology. These employees are proud to take part in these aforementioned research and innovation projects, and to have the opportunity to work with forward-looking companies, institutions and entrepreneurs in shaping the future. Below is a brief overview of the 14 projects that were completed last week.
The picture shows the distribution of new projects by Matís and partners around the country.
Icelandic Food Innovation Fund (is. Matvælasjóður)
Development of Icelandic oat milk: Sandhóll bú ehf. in Vestur-Skaftafellssýsla received a grant for the development of oat milk from domestic raw materials. Oat milk from Icelandic oats is a novelty in Iceland that will increase the value of domestic oat production, and replaces imported oat milk and therefore has, among other things, less carbon footprint than the imported product. Sandhóll enjoyed Matís 'loyal assistance in formulating the project and in writing the application, and Sandhóll will use Matís' services in the implementation of the project. Matís sincerely congratulates the couple at Sandhóll, Hellen M. Gunnarsdóttir and Erni Karlsson, on their grant.
Healing power of organic whey in a jar: Biobú ehf. received a grant for the development of cosmetics from organic whey. In 2009, a study was carried out at Matís where the bioactivity of whey was measured, but the study showed that whey has antioxidant properties. It has also been shown to lower blood pressure. Following on from these positive results, a study was started on the utilization of whey in face cream in collaboration with Bíóbú. Those projects were funded by Milk in Many Figures (MiMM) and the Agricultural Productivity Fund. Biobú now intends to continue this development and innovation project, so that valuable products will be produced and marketed from this underutilized raw material. Biobú enjoyed Matís' loyal assistance in shaping the project and in writing the application. Biobú will use Matís' services in the implementation of the project. Matís warmly congratulates the owners and staff of Biobú on the grant.
Protein powder from mackerel sidestreams: The herring processing plant in Neskaupstaður (SVN) received a grant to develop and produce fish protein hydrolysates from tributaries that are generated during the processing of mackerel and assess the feasibility of using them in starter feed for salmon farming, as well as for human consumption. Mackerel is one of the most important pelagic species in Iceland and more than 100,000 tonnes are processed in the country every year, with the associated amount of tributaries (heads, viscera and cuttings). Until now, these tributaries have only been used for the production of fishmeal and fish oil, and there are therefore great opportunities to increase their value. SVN is the owner of the project, but if the project achieves the desired results, it will be of significant importance for the pelagic sector as a whole, as well as for feed and aquaculture companies in this country. SVN has already made a significant investment to carry out this research and development work, and it is therefore particularly positive that the Food Fund also has faith in the project. SVN and Fóðurverksmiðjan Laxá are responsible for the project and enjoyed Matís' assistance in shaping the project and in preparing the application. SVN will use Matís 'services for the project, where Matís' employees in Neskaupstaður will play a key role. Matís sincerely congratulates the forward-thinking owners, management and staff of SVN on the grant.
Forest system - Weeds or underutilized food resource: Sýslið verkstöð ehf. in Hólmavík received a grant to explore the possibility of using a forest system in food. The county workshop received Matís 'assistance in shaping the project and will use the assistance of Matís' experts in the implementation. Matís sincerely congratulates Ásta Þórisdóttir, owner of Sýslið verkstöð, on the grant.
Processing of salmon products in Iceland: Where are the opportunities for filleting and by-products: Freysteinn Nonni Mánason received a grant to carry out a preliminary survey on the feasibility of increased processing of salmon products at Oddi in Patreksfjörður. Employees of Matís and the University of Iceland will play a guiding role in the project. Matís congratulates Freystein on his grant and this interesting project.
New antioxidants and stability of mackerel flour: The herring processing plant in Neskaupstaður (SVN), together with Skinney-Þinganes, Ísfélag Vestmannaeyja and Matís received funding to assess the stability of Icelandic mackerel flour and examine the properties and effectiveness of various antioxidants with a view to finding a suitable successor to ETQ, which was recently banned. The substance ETQ has been used in the Icelandic fishmeal industry for many years due to how effective it is in counteracting the development of fat in flour. Following the ban, fishmeal producers have encountered problems with the formation of heat in mackerel meal, which can be directly attributed to the development of fat in the meal. Heat generation in flour can significantly reduce the value of the flour due to damage to it, but there is also a risk of self-ignition in the flour. This is an extremely important project for the entire pelagic sector and society as a whole. Matís' experts are excited to start working on this important project. Matís' work on the project will largely be done in the company's branch in Neskaupstaður.
Oatmeal: The Agricultural University, in collaboration with Matís, received a grant to promote a new sector of Icelandic grain cultivation by identifying the best oat cultivars in terms of cultivation and quality. The foundation will be laid in the project to start targeted breeding of oats for Icelandic conditions. This type of grain cultivation will be introduced to farmers and the cultivation limits will be examined. Special attention will be paid to the Nordic countries in this connection. Matís congratulates the Agricultural University on the grant and the company's experts are excited to start the work.
Shark effect: Matís and Bjarnarhöfn Stykkishólmur received a grant to gain new knowledge about the complex changes that take place during shark chewing and drying and make it this special food it is, with the aim of reducing fluctuations in product quality, standardizing production and promoting to the possible export of this unique food. The best shark is popular with tourists and is often talked about on online media as the national dish of Icelanders. There is interest in buying sharks from Iceland, but there are difficulties in exporting due to traditional production methods and the product does not have an export license. It is likely that this interesting and timely project will open up new opportunities for value creation of underutilized raw materials. Matís congratulates Bjarnarhöfn on the grant and expects a successful collaboration in the coming year.
Valuable material from sideline algae processing: Matís, the University of Iceland, Thorverk, Þörungaklaustur, Ora and Síldarvinnslan in Neskaupstaður received funding to explore the possibility of increased processing to increase the value of algae, as well as the development of methods to extract them. Subsequently, it can be assumed that there will be great opportunities for innovation and, if successful, that the competitiveness of Icelandic producers will be strengthened, through the utilization of natural additives that are made in a sustainable way from organic raw materials. Matís congratulates partners on the grant.
Analysis of ringworms in fillets: Matís, University of Iceland, Marel, Vísir hf. and SFS received funding to evaluate the potential and feasibility of utilizing multispectral imaging (MSI) technology to detect ringworms in fillets. This is a huge interest for the fishing industry and the economy as a whole, and Matís' experts are proud and excited about the project, in addition to which they are grateful for the collaboration with these powerful partners.
Stress salmon fishing: Matís, Skaginn 3X and Arctic Fish received funding to develop and verify a new type of pump for pumping live salmonids. This pump will improve the handling of live fish, reduce stress and reduce the cost and quality of aquaculture companies. The project will largely be carried out in the Westfjords. Matís expects a lot from this interesting project.
Vegetable value chain: Matís, Háskóli Íslands and Samkaup received grants to improve quality, shelf life and reduce waste in the value chain of Icelandic vegetables. The aim of the project is to strengthen the vegetable sector in Iceland with new knowledge that supports the development of the sector, which means increased production, more employment opportunities and an increased supply of nutritious products. The opportunities are based on a larger domestic market share and exports. This is a very exciting project that Matís' experts are interested in starting in the new year.
Marketing plan for societal challenges
Matís, Atmonía ehf., Landbúnaðarháskólinn, Nýsköpunarmiðstöð, Landgræðslan and Landsvirkjun received grants to improve the utilization of domestic resources and by-products with the aim of producing sustainable fertilizers for Icelandic agriculture and land reclamation. The project will last for two years and will probably have a very large financial and environmentally friendly impact on Icelandic society. Matís congratulates partners on the grant.
H2020 - European Framework Program for Research and Innovation
Matís, together with a number of partners across Europe, received a € 7.5 million grant last week to analyze and develop bioactive ingredients from natural ingredients. Matís' project component will be based on the results of extensive research into the marine environment, including individual microbial communities of marine hotspots along the country's shores. The project will run for four years and Matís' share is 600 thousand Euros, or about 90 million ISK.
As you can see from the list above, there are exciting times ahead. In the coming months, the various funds, domestic and international, will be open to applications. If you are interested in increasing value, utilization and sustainability and creating jobs, we encourage you to contact Matís to discuss the possibility of collaboration. Matís is a key partner in research and innovation in the field of food and biotechnology in Iceland. We conduct research and innovation for your benefit.
When the public limited company Matís was founded in 2007, half of the company's income was secured through a service agreement with the state. The value of the agreement at the beginning was around ISK 700 million. (1200 million at today's exchange rate). However, it was a joint decision of Matís and the authorities to reduce the weight of this agreement and that instead the company should apply for a competition fund, which would further ensure that the projects being worked on are macroeconomically important as well as important for food producers in the country. Matís' annual income from a service agreement with the state is now almost 400 million, about 25% of the company's turnover, which is intended to ensure security services in the field of food safety and support research and innovation in food production in Iceland. About 75% of the revenue comes from domestic and foreign competition funds, as well as from direct sales of services and consulting.
Fisheries Project Fund, Ministry of Fisheries and Agriculture
Contact
Viggó Marteinsson
Research Group Leader
viggo@matis.is
Optimization of sample preparation - filtration and DNA extraction - for the analysis of sea water samples
Little is known about microorganisms or the diversity of microbial communities in Icelandic waters, but they play an important role in the marine ecosystem. It is necessary to study the microbiology of the ocean around Iceland with new and powerful methods based on molecular biology. In such work, the quality of the samples and sample preparation are very important. In this study, a preliminary survey of sea samples, sampling and sample handling was performed before large quantities of samples are taken. First, samples were taken from the marina in Reykjavík for preliminary study and then we continued with samples from the open sea. Yields were examined for DNA levels and how well the microorganisms' genes were amplified by PCR. The results showed that the best method was a purchased DNA isolation kit that isolated most of the DNA and was quantifiable by PCR. A cheaper and faster method with an automatic isolator and home-made substrates also proved to be very successful, as comparable results were obtained from PCR amplification, although lower DNA recovery was obtained. Based on these results, it is possible to set up procedures based on automatic DNA isolation of samples but the use of purchased isolation kits on more difficult samples. It is planned to use these results for sea samples from the Marine Research Institute's spring survey.
The knowledge on microbial diversity and community structure in Icelandic seawater is scarce at present despite their important role in ocean ecology. The agenda is to increase our knowledge in this field by applying recent and powerful analytical tools. In order to do that it is essential to have access to high quality samples and sample preparation procedures. In the present study sea sample preparation was studied with aim of comparing different methods and optimizes the workflow. Samples from a harbor in Reykjavík and open sea samples were used for this purpose. The results showed that an extraction method based on an Epicenter kit gave the best results regarding DNA recovery from the samples and suitability in a PCR amplification. However, a method based on semi ‐ automatic protocol and in house reagents proved to be more cost effective and showed comparable performance with PCR suitability of the samples although a lower DNA recovery was obtained. From these results it is now possible to establish an efficient work flow for microbial diversity analysis of sea samples using an automated method as a first choice with the option of more costly method for more challenging samples.
Margeir Gissurarson, Hannes Magnússon, Ragnheiður Sveinþórsdóttir, Cecilia Garate
Supported by:
AVS Research Fund
Contact
Margeir Gissurarson
Strategic Scientist
margeir.gissurarson@matis.is
Compilation of previous test results of capelin roes / Compilation of previous test results of capelin roes
In recent years and decades, various measurements and research on capelin roe in Iceland have been carried out at Matís ohf / Rannsóknastofnun fiskiðnaðarins. This is primarily a study of microorganisms, egg filling and water content. The report will cover microbial research carried out during the 1984 season, microbiological measurements in the period 2000-2008 and measurements of water content and egg filling 1984-2008.
In recent years and decades various studies and measurements have been carried out on capelin roes in Iceland at Matís ohf / Icelandic Fisheries Laboratories. They mainly include studies on microorganisms, roe-fill and water content. In this report, microbial studies on microorganisms from the capelin season 1984 are presented along with microbial measurements carried out during 2000-2008 and measurements of roe-fill and water content 1984- 2008.
María Guðjónsdóttir, Hannes Magnússon, Kolbrún Sveinsdóttir, Björn Margeirsson, Hélène L. Lauzon, Eyjólfur Reynisson, Emilía Martinsdóttir
Supported by:
AVS Research Fund, Rannís Technology Development Fund
Contact
Kolbrún Sveinsdóttir
Project Manager
kolbrun.sveinsdottir@matis.is
Effect of modified atmosphere packaging (MAP) and superchilling on the shelf life of fresh cod (Gadus morhua) loins of different degrees of freshness at packaging
The purpose of this experiment was to evaluate the effect of aerated packaging (MAP) and supercooling on the quality changes and shelf life of cod pieces of fresh raw material that was processed and packaged after 2 and 7 days of fishing. The experiment was carried out in collaboration with Samherji, Dalvík and Norðlenska, Akureyri in October and November 2007. The fish was stored whole in ice until packing at -0.2 ± 0.1 ° C (2 days from fishing) and -0.2 ± 0.2 ° C (7 days from fishing). The neck pieces were cut in half and then packed (350-550 g) in an airtight container. The composition of the gas mixture was as follows: 50% CO2, 5% O2 and 45% N2. Packaged cod pieces were stored in cold storage at -0.6 ± 1.4 ° C and samples were taken over a 3-week storage period and evaluated by sensory evaluation, microbial and chemical measurements. The age of the raw material during packaging had a clear effect on the sensory evaluation of the pieces. Packing after 2 days led to a prolongation of the freshness symptoms in front of storage. In addition, signs of damage appeared much later than in bites packed 7 days after fishing. The shelf life of pieces after packing on day 7 can be roughly estimated at 4-8 days, but at least 19 days in pieces packed on day 2. This short shelf life of pieces from day 7 can be explained by the development of microbial flora and the formation of volatile pesticides as well as the temperature profile of whole fish before packaging. The effect of different packing dates had a significant effect on the microflora. Thus, the total number of microorganisms was much smaller in pieces packed after 2 days than on day 7 (log 3.7 vs 5.4 / g). This difference can largely be attributed to the varying number of Photobacterium phosphoreum (Pp) in the flesh immediately after packing, but it was not detected during the previous packing on the 3rd day of the experiment (below log 1.3 / g) and on day 8 the number was only log 2.4 / g. On that day, the number of Pp was 1000x higher in pieces packed on day 7 and they were predominant throughout the storage period in this group. On day 8, the number of other pests (H2S-producing bacteria and pseudomonads) was somewhat higher (Δ log 0.6-0.7 / g) in this group compared to the group packed on day 2. These results confirm that P. phosphoreum is one of the main damaging microorganisms in gas-packed cod pieces but also in chilled, whole cod. The results of TVB-N and TMA measurements were in good agreement with microbial measurements, but especially Pp. Low Field Nuclear Magnetic Resonance (LF-NMR) technology was used to measure relaxation times in samples over the storage period. Significantly higher "relaxation times" were measured in chunks packed after 7 days of fishing than in chunks packed 2 days after fishing. It indicates greater binding of water molecules to the environment in the 7-day bites. This is in line with the generally higher water resistance and water content of those samples over the storage period. Overall, the results show the importance of using the freshest ingredients for MA packaging, thus ensuring higher quality and longer shelf life, which should result in a higher price for the product.
The aim of this study was to evaluate the effect of modified atmosphere packaging (MAP) and superchilling on the shelf life and quality changes of fresh loins prepared from Atlantic cod (Gadus morhua) of different freshness, ie processed 2 or 7 days post catch. The study was performed in cooperation with Samherji (Dalvík, Iceland) and Norðlenska (Akureyri) in October and November 2007. The average fish temperature during storage prior to processing on days 2 and 7 was -0.2 ± 0.1 ° C and -0.2 ± 0.2 ° C, respectively. Cod loins (350-550 g) were packed in trays under modified atmosphere (50% CO2 / 5% O2 / 45% N2), stored at -0.6 ± 1.4 ° C and sampled regularly over a three-week period for sensory, microbiological and chemical analyzes . The results show that the raw material freshness clearly influenced the sensory characteristics of packed loins. Processing 2 days post catch resulted in more prominent freshness sensory characteristics the first days of storage. In addition, sensory indicators of spoilage became evident much later compared to MApacked fillets from raw material processed 5 days later. The expected shelf life of the MA-packed cod loins could be roughly calculated as 4-8 days when processed 7 days post catch, but at least 19 days when the cod was processed 2 days post catch. This reduced shelf life of MAP products processed at a later stage was also explained by the temperature profile of the whole fish prior to processing, microbial development and volatile amine production observed. In fact, the day of packaging had a major effect on the microflora development, with lower total viable counts (TVC) in loins processed earlier in relation to time from catch (log 3.7 vs 5.4 / g). This difference could be linked to large variations in levels of Photobacterium phosphoreum (Pp) in the flesh at processing times, being below detection (log 1.3 / g) 2 days post catch but found to increase to log 2.4 / g in early processed loins 6 days later, in contrast to 1000-fold higher Pp levels in loins processed later. Pp was found to quickly dominate the microflora of loins processed 7 days post catch. Similarly, slightly higher levels (Δ log 0.6- 0.7 / g) of other spoilage bacteria, H2S-producing bacteria and pseudomonads, were found 8 days post catch in loins processed later. These results confirm that P. phosphoreum is one of the main spoilage organisms in cod, unprocessed as MA-processed. TVB-N and TMA production corresponded well to the microbial development, especially counts of P. phosphoreum. Low Field Nuclear Magnetic Resonance (LF-NMR) was used to measure the relaxation times of the samples during storage. The samples packed 7 days after catch showed significantly higher relaxation times than samples packed 2 days after catch. This indicates stronger bindings of the water molecules to their environment in samples packed at a later stage. This is in agreement with the generally higher water holding capacity and water content in the samples during storage. Finally, the results demonstrated that delaying processing of raw material is undesirable if it is intended to be MA-packed and sold as more valuable products.
María Guðjónsdóttir, Kolbrún Sveinsdóttir, Hannes Magnússon, Sigurjón Arason
Supported by:
Rannís Research Fund
Contact
Kolbrún Sveinsdóttir
Project Manager
kolbrun.sveinsdottir@matis.is
Shelf life tests on cod pieces: Effects of supercooling on salt and protein injected cod muscles
An integrated refrigeration study was performed on the effects of salting, protein injection and subcooling on the quality, chemical and physical properties of salt and protein injected cod muscles. The study shows that by injecting salt and protein into the muscle, utilization can be improved, drip reduced and the boiling efficiency of the muscle increased. On the other hand, the injection of salt and protein into muscles increases microbial growth and the formation of erratic alkalis, thus shortening the shelf life of the product. However, lowering the storage temperature could inhibit the growth of microorganisms and the formation of erratic alkalis. Decreased storage temperature, however, led to cell damage due to ice formation on the surface regardless of the salinity of the muscle. Therefore, it is not considered desirable to store fresh or lightly salted cod muscle at temperatures below -2 ° C. The effect of rinsing the samples in a brine bath after injection was also investigated. Such rinsing did not significantly affect the water and salinity or efficiency of the samples, but showed a reduction in the formation of erratic bases. It is therefore advisable to rinse fillets in brine after injection to prevent damage to the best extent possible. Sensory evaluation results showed that the properties of the muscle changed significantly with the injection of salt and protein into the muscle, but the injected groups lost their freshness characteristics until the fresh untreated control group.
A combined cooling experiment was performed on the effect of salting, protein injection and superchilling on the quality and physicochemical properties of brine and protein injected cod muscle. The study showed that brine and protein injections lead to increased processing and cooking yield, as well as decreased drip. Injection of salt and proteins increase on the other hand microbiological growth and the formation of volatile nitrogen bases, which in turn leads to shorter shelf life. By lowering the storage temperature this growth of microorganisms and volatile nitrogen bases could be decreased. If the storage temperature is kept too low this on the other hand led to cell damages due to ice crystallization on the muscle surface, independent on the salt content of the muscle. It is therefore not recommended to store fresh and light salted cod at temperatures below -2 ° C. The study also viewed the effect of brining the muscle after brine and protein injection. This brining had no significant effect on the salt or water content of the muscle but decreased the amount of volatile bases. It is therefore recommended that cod muscle is always washed in brine after injection to keep damaging processes at a minimum. Sensory analysis showed a significant difference between the characteristics of brine and protein injected samples to unprocessed cod muscle. The injected groups also lost their freshness characteristics earlier than the unprocessed control group.
Ásbjörn Jónsson, Guðrún Anna Finnbogadóttir, Guðjón Þorkelsson, Hannes Magnússon, Ólafur Reykdal, Sigurjón Arason
Supported by:
AVS Research Fund, (AVS-Fund)
Contact
Guðjón Þorkelsson
Strategic Scientist
gudjon.thorkelsson@matis.is
Dried fish as health food
One of the main goals of the project was to obtain basic information about the properties of Icelandic dried fish and that the information would be open and thus for the benefit of all dried fish producers in Iceland. The main conclusion of the project is that dried fish is a very rich protein source with 80-85% protein content. The amino acids were measured and compared with amino acids in eggs. The result is that dried fish proteins are of high quality. These results support the marketing of dried fish as both a healthy food and a national food. It is important to look at the salt content in dried fish better and try to reduce it to increase the health of dried fish, especially in hot-dried dried fish, as it was much higher than in other dried fish. Measurements of trace elements showed that their amount in dried fish is well within limits compared to the recommended daily allowance (RDS) except in selenium. Its amount in 100 g is three times the recommended daily dose. However, it is not considered harmful in any way.
The main object of this project was to provide information of the quality in Icelandic dried fish to be of benefit for all producers in Iceland. The main results showed that dried fish was a very rich source of proteins, containing 80-85% protein. Amino acids were measured and compared to the amino acids in eggs. It was concluded that the proteins in the dried fish were of high quality. This supports the marketing of dried fish in the health foods and traditional food markets. It is important to better analyze the salt content in dried fish and reduce it to improve balanced diet in dried fish, especially for indoor produced dried fish, which salt content is rather high. The trace elements in dried fish showed minimal content, except for selen where the content was threefold the recommended daily allowance (RDA). This is not hazardous for people in any way.
The value and safety of Icelandic seafood. Food safety and added ranking / Food safety and added value of Icelandic seafood. Risk profiling and risk ranking
In this project, basic work was carried out on risk assessment for cod, shrimp, redfish, haddock, halibut, herring, saithe and kúfisk. These species were mapped for risk and their risk composition was obtained and a semi-quantitative risk assessment was performed on them. This risk assessment used a calculation model that has been developed in Australia and is called Risk Ranger. The risk assessment used data on consumption habits (dosages, frequency, etc.), frequency and causes of foodborne illness. Thus, the risk associated with the consumption of these marine products was calculated, based on certain assumptions. The reliability of a risk assessment is entirely dependent on the data and information used in its implementation. According to the available measurement data and given assumptions, the above-mentioned seafood products are classified in the lowest risk category (level <32) - low risk, compared to healthy individuals. In international food markets, Icelandic seafood has a good reputation for health and safety. Concerns about food safety, however, are growing in many places, so it is a great challenge for Icelanders to maintain this good reputation in the future.
This report contains the preliminary results of a risk profiling and risk ranking study for the following species: cod (Gadus moruha), shrimp (Pandalus borealis), ocean perch (Sebastes marinus), haddock (Melanogrammus aeglefinus), Greenland halibut (Reinhardtius hippoglossoides) , saithe (Pollachius virens) and Iceland cyprine (Cyprina islandica). These species were surveyed with regard to terms of undesirable substances (Risk profiling and risk ranking, as well as semiquantitative risk assessment). An Australian software, Risk ranger, was used to compute the risk assessment. Various data, eg consumer behavior (daily intake, frequency etc.), and incidence and origin of food-borne diseases, were used. Thus, the risk of consuming these species was determined. The reliability of a risk assessment is dependent on the quality of the data which are used to carry it out. Based on the existing data and given prerequisites, it can be stated that the aforementioned species come under the lowest risk group (degree <32) - small risk, considering healthy individuals. Icelandic seafood products are renowned on the international food markets as being quality and safe food. However, in light of growing concern worldwide for food safety, it is a challenge for Icelandic seafood producers to maintain that good reputation.
