Reports

Functionality testing of selected Chill ‐ on technologies during a transport ‐ simulation study of palletized cod boxes: qPCR for fish spoilage bacteria, SLP model and QMRA to evaluate pathogen growth in spiked cod

Published:

01/11/2010

Authors:

Hélène L. Lauzon, Björn Margeirsson, Kolbrún Sveinsdóttir, Eyjólfur Reynisson, María Guðjónsdóttir, Emilia Martinsdóttir (Matís); Radovan Gospavic, Nasimul Haque, Viktor Popov (WIT); Guðrún Ólafsdóttir, Tómas Hafliðason, Einir Guðlaugsson, Sigurður Bogason (UoI)

Supported by:

EU IP Chill ‐ on (contract FP6‐016333‐2)

Contact

Kolbrún Sveinsdóttir

Project Manager

kolbrun.sveinsdottir@matis.is

Functionality testing of selected Chill ‐ on technologies during a transport ‐ simulation study of palletized cod boxes: qPCR for fish spoilage bacteria, SLP model and QMRA to evaluate pathogen growth in spiked cod

In this study, tests were carried out on technical solutions developed in the EU project Chill ‐ on, where a simulation experiment was set up to simulate the actual transport of fish from Iceland to Europe. The temperature fluctuations experienced by the fish were aimed at mimicking transport from Iceland to France by ship. Pallets of cod fillets in foam plastic boxes were transported to the Westman Islands by ship and back to Matís in Reykjavík. Samples from these pallets were then compared with control samples that had been stored in Matís' refrigerated conditions. Cod nuggets were also packed in consumer packs (trays) immediately after processing and then after 6 days and were stored in subcooled or refrigerated conditions. Microbial growth experiments were also performed in which Listeria monocytogenes, Escherichia coli and Salmonella Dublin were added to cod necks stored in foam boxes in conditions similar to the storage and transport processes during export. Temperature measurements, sensory evaluation, microbial and chemical measurements were used to present data to test and verify the QMRA / SLP models and quantification of Pseudomonas bacteria using qPCR technology.

The aim of the cod wet trials and the corresponding shelf life study was to include scenarios to test and demonstrate the functionality of some Chill ‐ on technologies in a simulated cod supply chain. Temperature fluctuations were induced according to the actual scenario in the supply chain of cod from Iceland to France via sea freight. The study included sample groups created at the point of processing after packaging in EPS boxes. The reference group was stored at Matís under superchilled conditions. Simulation trials for downward distribution were performed at Matís upon receipt of the pallets shipped to the Westman Isles from Reykjavik (Iceland ‐ Europe freight simulation) and compared with the reference group. Repackaging of loins in retail trays was performed on days 0 and 6 with storage under superchilled and chilled conditions, respectively. In addition, a pathogen challenge trial was performed by spiking loins (5 kg) with Listeria monocytogenes, Escherichia coli and Salmonella Dublin, followed by storage in EPS boxes under temperature conditions simulating export and distribution. Temperature recordings along with microbial, chemical and sensory analyzes from the groups evaluated provided necessary data to test and validate the QMRA / SLP models and the quantitative molecular (qPCR) method to estimate counts of pseudomonads.

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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

Íslenskt bygg til matvælaframleiðslu / Icelandic barley for food production

Published:

01/12/2008

Authors:

Ólafur Reykdal (editor / editor), Jónatan Hermannsson, Þórdís Anna Kristjánsdóttir, Jón Óskar Jónsson, Aðalheiður Ólafsdóttir, Emilia Martinsdóttir, Birgitta Vilhjálmsdóttir, Jón Guðmundsson, Guðmundur Mar Magnússon.

Supported by:

The Agricultural Productivity fund

Contact

Ólafur Reykdal

Project Manager

olafur.reykdal@matis.is

Íslenskt bygg til matvælaframleiðslu / Icelandic barley for food production

The project "Increased value from Icelandic barley" was carried out in the years 2006 to 2008 in collaboration with Matís ohf, the Agricultural University of Iceland, barley producers and food companies. Measurements were made of nutrients, contaminants and microorganisms in the building. The hygienic beta-glucans, which are water-soluble fiber, attracted special attention. The safety of the barley was satisfactory according to measurements of microorganisms and contaminants. Tests on baking barley bread took place in companies and it was shown that Icelandic barley is well suited for baking products. Sensory evaluation and consumer surveys were conducted on barley bread and similar breads without barley. The barley bread had its own characteristics and received generally good reviews. Barley malt was produced and then used as a raw material in brewing. It was possible to produce beer of satisfactory quality, but the main problem with the malt production was the low germination rate of the barley. Draft quality requirements for Icelandic barley for the production of baked goods and barley malt were compiled.

The project “Increased value of Icelandic barley” was carried out during the years 2006 to 2008 in cooperation between Matis ohf, Agricultural University of Iceland, barley producers and food manufacturers. Nutrients, contaminants and microbes were measured in Icelandic barley. The water soluble dietary fiber, beta-glucan, was of special interest. The safety of Icelandic barley was sufficient according to measurements of contaminants and microbes. Barley was tested for bread baking and the result was that Icelandic barley can be used for bread making. Breads with and without barley were tested by sensory evaluation and consumer testing. Barley breads had special sensory properties and were well accepted. Malt was produced from Icelandic barley and used for production of beer. The beer was of good quality but the main problem with the malt production was low proportion of sprouting barley. Quality criteria were drafted for Icelandic barley for production of bakery products and malt.

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