Matís Staff

List of Employees

Margrét Geirsdóttir

Project Manager

Group: Bioactive Compounds

Phone: +354 4225089 /

Email: mg@matis.is

Bibliography / Orcid website

LinkedIn

Focus Areas:

Functional properties, Enzymes, Functional Food, Peptides, Protein, Bioactive properties, Collagen

Peer-reviewed Articles:

  • A. Tzachor, SP van den Oever, HK Mayer, M. Asfur, A. Smidt‐Jensen, M. Geirsdóttir, S. Jensen, BO Smárason. Photonic management of Spirulina (Arthrospira platensis) in scalable photobioreactors to achieve biologically active unopposed vitamin B12 - (2024). Discover Food, Volume 4, article no. 69. doi.org/10.1007/s44187-024-00152-1

  • Qian Zhang, Ru Liu, Margrét Geirsdóttir, Shiyu Li, Tumi Tomasson, Shanbai Xiong, Xiuchen Li, María Gudjónsdóttir. Thermal-Induced Autolysis Enzymes Inactivation, Protein Degradation and Physical Properties of Sea Cucumber, Cucumaria frondosa - (2022). Processes , 10(5), 847, 10(5), 847. 10.3390/pr10050847

  • Asaf Tzachor, Asger Smidt-Jensen, Alfons Ramel, Margrét Geirsdóttir. Environmental Impacts of Large-Scale Spirulina (Arthrospira platensis) Production in Hellisheidi Geothermal Park Iceland: Life Cycle Assessment - (2022). Marine Biotechnology , 24, 991–1001 .

  • Margrét Geirsdóttir, H. Hlynsdottir, Guðjón Þorkelsson, Sjöfn Sigurgísladóttir. Solubility and viscosity of herring (Clupea harengus) proteins as affected by freezing and frozen storage - (2007). Journal of Food Science, 72(7), 376-380.

  • Guðjón Þorkelsson, Sjöfn Sigurgísladóttir, Margrét Geirsdóttir, Ragnar Jóhannsson, F Guérard, A Chabeaud, P Bourseau, L Vandanjon, P Jaouen, M Chaplain-Derouiniot, M Fouchereau-Peron, O Martinez-Alvarez, Y Le Gal, R Ravallec-Ple , L Picot, JP Berge, C Delannoy, G Jakobsen, I Johansson, I Batista, C.Pires. Mild processing techniques and development of functional marine protein and peptide ingredients In: Improving seafood products for the consumer - (2008). Cambridge, Woodhead Publishing Ltd., , 363-398.

  • Margret Geirsdottir, Hordur G. Kristinsson, Sjofn Sigurgisladottir, Patricia Yuca Hamaguchi, Gudjon Thorkelsson, Ragnar Johannsson, Magnus Mar Kristjansson. Enzymatic hydrolysis of blue whiting (Micromesistius poutassou); functional and bioactive properties - (2011). Journal of Food Science, 76(1), C14-C20.

  • Jamnik, P., Istenic, K., Kostomaj, T., Wulff, T., Geirsdóttir, M., Almgren, A., Jónsdóttir, R., Kristinsson, HG, Undeland, I .. Bioactivity of cod and chicken protein hydrolysates before and after in vitro gastrointestinal digestion - (2017). Food Technology and Biotechnology, 55(3), 360-367.

  • Jonsdottir, R., Geirsdottir, M., Hamaguchi, PY, Jamnik, P., Kristinsson, HG, Undeland, I .. The ability of in vitro antioxidant assays to predict the efficiency of a cod protein hydrolyzate and brown seaweed extract to prevent oxidation in marine food model systems - (2016).  Journal of the Science of Food and Agriculture, 96(6), 2125-2135.

    • RITASKRÁ / Publications

    REVIEWED ARTICLES / Articles in peer-reviewed journals:

    2017:

    Jamnik P, Istenič K, Koštomaj T, Wulff T, Geirsdottir M, Almgren A, Jonsdottir R, Kristinsson HG, Undeland I. 2017. Bioactivity of Cod and Chicken Protein Hydrolysates before and after in vitro Gastrointestinal Digestion. Food Technology and Biotechnology 55 (3).

    2015:

    Jónsdóttir R, Geirsdóttir M, Hamaguchi PY, Jamnik P, Kristinsson HG, Undeland U. 2015. The ability of in vitro antioxidant assays to predict the efficiency of a cod protein hydrolyzate and brown seaweed extract to prevent oxidation in marine food model systems. Journal of the Science of Food and Agriculture 96 (6) · 2125-2135.

    Jónsdóttir R, Geirsdóttir M, Hamaguchi PY, Jamnik P, Kristinsson HG, Undeland U. 2015. The ability of in vitro antioxidant assays to predict the efficiency of a cod protein hydrolyzate and brown seaweed extract to prevent oxidation in marine food model systems. Journal of the Science of Food and Agriculture 96 (6) · 2125-2135. https://doi.org/10.1002/jsfa.7328

    2014:

    Kristinsson H, Lanier TC, Halldórsdóttir SM, Geirsdóttir M, Park JW. 2014. Fish Protein Isolate by pH Shift In Suirmi and Surimi Seafood, 3ed. Ed Jae Park, pp: 169-192. CRC Press, New York. https://doi.org/10.17113/ftb.55.03.17.5117

    2011:

    Margret Geirsdottir, Hordur G. Kristinsson, Sjofn Sigurgisladottir, Patricia Yuca Hamaguchi, Gudjon Thorkelsson, Ragnar Johannsson, Magnus Mar Kristjansson. 2011. Enzymatic hydrolysis of blue whiting ( Micromesistius poutassou); functional and bioactive properties. Journal of Food Science. 76 (1), C14-C20. Article

    2007:
    Margrét Geirsdóttir, H. Hlynsdottir, Guðjón Þorkelsson and Sjöfn Sigurgísladóttir. 2007. Solubility and viscosity of herring ( Clupea harengus) proteins as affected by freezing and frozen storage. Journal of Food Science, 72, no. 7 .: 376-380. Read the article  Article

    2002:
    Thorarinsdottir KA, Arason S., Geirsdottir M., Bogason SG and Kristbergsson K. 2002. Changes in myofibrillar proteins during processing of salted cod ( Gadus morhua) as determined by electrophoresis and Differential Scanning Calorimetry. Food chemistry, 77(3), 377-385.

    BOOK CHAPTERS

    Kristinsson H, Lanier TC, Halldórsdóttir SM, Geirsdóttir M, Park JW. 2014. Fish Protein Isolate by pH Shift In Suirmi and Surimi Seafood, 3ed. Ed Jae Park, pp: 169-192. CRC Press, New York.

    Guðjón Þorkelsson, Sjöfn Sigurgísladóttir, Margrét Geirsdóttir, Ragnar Jóhannsson, F Guérard, A Chabeaud, P Bourseau, L Vandanjon, P Jaouen, M Chaplain-Derouiniot, M Fouchereau-Peron, O Martinez-Alvarez, Y Le Gal, R Ravallec-Ple , L Picot, JP Berge, C Delannoy, G Jakobsen, I Johansson, I Batista, C.Pires. 2008. Mild processing techniques and development of functional marine protein and peptide ingredients In: Improving seafood products for the consumer. Edited by T. Börresen. Cambridge, Woodhead Publishing Ltd.  More about the book.

    LECTURE AT CONFERENCES / Oral presentations:

    2011:

    Margrét Geirsdóttir, Patricia Hamaguchi, Óli Þór Hilmarsson, Irek Klonowzki, Hörður G. Kristinsson. Surimi seafood from byproducts containing omega-3 fatty acids. Presentation: 41 st WEFTA Meeting, 27-30 September 2011, Gothenburg, Sweden.

    Kolbrún Sveinsdóttir, Rósa Jónsdóttir, Margrét Geirsdóttir, Emilia Martinsdóttir. Innovative consumer-oriented product development of enriched seafood. Presentation: 41 st WEFTA Meeting, 27-30 September 2011, Gothenburg, Sweden.

    S. Crynen, MR Marshall, HG Kristinsson, P. Hamaguchi, H. Sveinsdottir, M. Geirsdóttir. Antioxidant properties of peptides derived from cod muscle myosin by enzymatic hydrolysis with trypsin, chymotrypsin and elastase. IFT Annual meeting and food expo, New Orleans, 2011. Poster presentation.

    H. Sveinsdottir, P. Hamaguchi, H. G Kristinsson, M. Geirsdottir. Bioactivity of marine derived peptides analyzed with a cellular antioxidant assay. IFT Annual meeting and food expo, New Orleans, 2011. Poster presentation.

    2009:
    Sigrún Mjöll Halldórsdóttir, Patricia Y. Hamaguchi, Margrét Geirsdóttir, Guðjón Þorkelsson, Hörður G. Kristinsson and Arnljótur B. Bergsson. Antihypertensive properties of protein from whey and whey. Agricultural Research Council 2009, 12 - 13 February, 6th year, p. 375-379. Read the article.

    2006:
    Margrét Geirsdóttir. Targeted foods and new foods. Paper presented at the food day of the Icelandic Food and Nutrition Association (MNÍ), Lofteiði, 20 October 2006.

    2005:
    Ragnar Jóhannsson, Margrét Geirsdóttir, Guðjón Þorkelsson, I. Batista, C. Pires. 2005. Functional properties of proteins from seafood by-products. Paper presented at the 2nd SEAFOODplus Conference, in Granville, France, October 5, 2005.

    Margrét Geirsdóttir, Guðjón Þorkelsson, Ragnar Jóhannsson, DE Ramsøy, B. Gundesen, NK Sørensen. 2005. Properties of fish proteins isolated in a pilot plant. Paper presented at the 35th WEFTA meeting in Antwerp, Belgium, 19-22. September 2005.

    Kári Óalfsson, Margrét Geirsdóttir. Is there power in Icelandic sea edema? Paper presented at IFL's Autumn Meeting, Grand Hotel 23.09. 2005.

    2003:
    Margrét Geirsdóttir, Harpa Hlynsdóttir. 2003. Protein solubility of herring proteins as affected by by freezing and frozen storage. Paper presented at TAFT 2003 - The First Joint Trans-Atlantic Fisheries Technology Conference Reykjavík 11-14 June.

    Margrét Geirsdóttir, Guðjón Þorkelsson. 2003. Proteins and peptides from fish novel components from fish by-products. Paper presented at the conference "Valuable products from by-raw materials" at the Institute of Technology, November 7, 2003.

    2002:
    New products. Paper presented at a seminar on increasing the value of pelagic fish. Smáraskóli, Kópavogur, 5 September 2002.

    2000:
    Margrét Geirsdóttir & Guðmundur Stefánsson. Shelf life of industrially produced herring fillets as affected by handling and packaging. 30th WEFTA meeting, 19 - 22 June 2000, Tórshavn, Faroe Islands


    REPORTS:

    2018:

    Björnsdóttir B, Geirsdóttir M, Guðmundsdóttir EE, Þorkelsson G, Jónsdóttir R, Þórðarson G, Groben R, Knobloch S, Hauptmann AL, Vang J, Gunnarsdóttir I, Jóhannsson R, Schönemann-Paul LD, Smáradóttir SE. 2018. Biorefining and Biotechnology Opportunities in the West Nordic Region. Matís Report, 03-18. 55p.

    2015:

    Margrét Geirsdóttir. Full utilization of proteins from Lumpfish. Matís Report 12-15, 130 p. Closed report. Report summary

    2013:

    Margrét Geirsdóttir. Peeling and marketing of surimi and surimi product from bone marrow. Matís Report 03-14, 17p. Closed report.

    2009:
    Margrét Geirsdóttir. Isolation, purification and investigation of peptides from fish proteins with blood pressure decreasing properties / Isolation, purification and research on blood pressure lowering peptides from fish proteins. Matís Report 36-09, 34 s.

    2008:
    Arnljótur B. Bergsson, Margrét Geirsdóttir, Rósa Jónsdóttir, Þóra Valsdóttir, Hörður G. Kristinsson, Guðjón Þorkelsson. 2008. A brief summary of processing fish proteins. Matís report 36-08. Closed report.

    Guðjón Þorkelsson, Margrét Geirsdóttir, Ragnar Jóhannsson, Sigurður Hauksson, Sjöfn Sigurgísladóttir, Arnljótur Bjarki Bergsson, 2008. Fish protein as a dietary supplement. Matís report 11-08, 18 p.

    2007:
    Margrét Geirsdóttir, Guðmundur Óli Hreggviðsson, Lárus Freyr Þórhallsson, Rósa Jónsdóttir, Patricia Hamaguchi, 2007. Isolation, purification and research into blood pressure lowering peptides from fish proteins. Matís Report 48-07, 46 p.

    Lárus Freyr Þórhallsson, Margrét Geirsdóttir, Guðmundur Óli Hreggviðsson, Sigurður Vilhelmsson, Guðjón Þorkelsson. 2007. Antihypertensive effect (Ace-inhibiting activity) in Icelandic seafood - installation of measurement methods. Matís Report 10-07, 15 p.

    2006:
    Margrét Geirsdóttir (editor). 2006. Protein Isolation from Herring. IFL report 39-06, 110 pages.

    Margrét Geirsdóttir, Katrín Ásta Stefánsdóttir. 2006. Processing properties of blue whiting flour. IFL report 29-06, 40 pages.

    2005:
    Margrét Geirsdóttir, Katrín Ásta Stefánsdóttir. 2005. Icelandic sea cucumber. IFL report 28-05, 15 pages.

    Kristín Anna Þórarinsdóttir, Þóra Valsdóttir, Katrín Ásta Stefánsdóttir, Margrét Geirsdóttir, Ragnar Jóhannsson. 2005. The effects of protein isolate in chilled and frozen haddock fillets. IFL report 25-05, 64 pages.
     
    Margrét Geirsdóttir, Katrín Ásta Stefánsdóttir. 2005. Measurements of bioactive substances in Icelandic seafood - Installation of measurement methods. IFL report 23 - 05, 8 p.

    Helga Gunnlaugsdóttir, Margrét Geirsdóttir, Arnheiður Eyþórsdóttir, Hjörleifur Einarsson, Guðjón Þorkelsson. 2005. Bioactive substances in Icelandic seafood: Summary. IFL report 05 - 05, 20 pages.

    2004:
    Margrét Geirsdóttir, Ragnar Jóhannsson. 2004. Blue whiting as a target food. IFL report 11-04, 25 pages.

    2003:
    Margrét Geirsdóttir. 2003. Stability of frozen herring as a raw material for food processing. IFL report 15-03, 52 pages.

    Gústaf Hjálmarsson, Margrét Geirsdóttir, Páll G. Pálsson. 2003. Developing methods to tenderise bones in herring fillets. IFL report 03-03, 28 p.

    2002:
    Margrét Geirsdóttir. 2002. Stability of frozen cod products. IFL report 11-02, 54 pages.

    2001:
    Guðmundur Stefánsson, Margrét Geirsdóttir. 2001. Developing a Process for Automated Tuna Head Meat Recovery: Individual Progress report for the Period 01.04.00 to 31.10.00. IFL project report 07-01 to the EU, 5 pages.

    2000:
    Margrét Geirsdóttir and Guðmundur Stefánsson. 2000. Capelin protein. IFL project report 05-00 to RANNÍS, 11 pages.

    POSTERS

    S. Crynen, MR Marshall, HG Kristinsson, P. Hamaguchi, H. Sveinsdottir, M. Geirsdóttir. Antioxidant properties of peptides derived from cod muscle myosin by enzymatic hydrolysis with trypsin, chymotrypsin and elastase. IFT Annual meeting and food expo, New Orleans, 2011. Poster presentation.

    H. Sveinsdottir, P. Hamaguchi, H. G Kristinsson, M. Geirsdottir. Bioactivity of marine derived peptides analyzed with a cellular antioxidant assay. IFT Annual meeting and food expo, New Orleans, 2011. Poster presentation.

    P.Hamaguchi, M.Geirsdottir, A. Vrac, HG Kristinsson, H. Sveinsdottir, OH Fridjonsson, GO Hreggvidsson. In-vitro antioxidant and antihypertensive properties of Icelandic sea cucumber ( Cucumaria frondosa). IFT Annual meeting and food expo, Chicago, 2010. Poster presentation.

    Rósa Jónsdóttir, Margrét Geirsdóttir, Patricia Y. Hamaguchi, Hörður G. Kristinsson. Inhibition of hemoglobin-mediated lipid oxidation in washed cod muscle by bioactive compounds from marine source. Poster at the International Marine Ingredients Conference, Oslo, Norway, 20-21 September 2010.

    Rósa Jónsdóttir, Patricia Y. Hamaguchi, Margrét Geirsdóttir, Hörður G. Kristinsson. Bioactive compounds from Icelandic marine source. Poster at the International Marine Ingredients Conference, Oslo, Norway, 20-21 September 2010.

    Margret Geirsdottir, Rosa Jonsdottir, HordurG. Kristinsson, Patricia Yuca Hamaguchi, Annabelle Vrac. Comparison of bioactive properties of cod and chicken protein hydrolysates. Poster at the IFT Annual Meeting, Chicago, July 2010.

    CONFERENCE PROGRAM / Conference proceedings:

    2003:
    Margrét Geirsdóttir, Harpa Hlynsdóttir. 2003. Protein solubility of herring proteins as affected by by freezing and frozen storage. In: First Joint Trans-Atlantic Fisheries Technology Conference TAFT Meeting Reykjavík, 11-14 June, pp. 269-271.
     

    GENERAL ARTICLES IN NEWSPAPERS AND MAGAZINES / Articles in non-refereed journals

    2005:
    Margrét Geirsdóttir. Marine proteins: Something fishy. Interview in Innovate, the newsletter of the Nordic Innovation Center. Innovate no. 4 - 2005, 8-11.

    Margrét Geirsdóttir: Bioactive peptides. Article in Morgunblaðið March 30, 2005.

    2004:
    Margrét Geirsdóttir. 2004. Processing of bioactive peptides. Food is on the human side. Publications of the Icelandic Food and Nutrition Association (MNÍ) .16 (1): 18.

    Margrét Geirsdóttir. 2004. Bioactive peptides. Ægir, 97 (7): 36-37.

    2002:
    Harpa Hlynsdóttir, Margrét Geirsdóttir. 2002. Surimi: Is it something for the Icelandic fishing industry? Ægir, 95 (10): 16–18.
     

    TEACHING / Teaching:

    Part-time teaching at the United Nations Fisheries Academy
    Part-time lecturer at the Department of Food Science at the University of Iceland from 1999-2002 in practical teaching in food chemical analysis.
    Part-time teaching at the Fish Processing School spring semester 2000/2001.