Lumpfish (Cyclopterus lumpus) used as cleaner fish: Characterization and suitability for human consumption

Farmed lumpfish (Cyclopterus lumpus) is frequently used as cleaner fish in Norwegian salmon aquaculture. During the period in the net cage, the lumpfish feed on salmon lice. After a time, the fish stop eating the lice and are then withdrawn from the net cage without further exploitation. In this study, the nutritional value of lumpfish was characterized to assess its suitability as a human food. The lumpfish were collected from two separate salmon aquaculture facilities and analyzed for proximate composition, amino acids, fatty acids, vitamins, minerals, environmental pollutants, and heavy metals. The water and protein content were approximately 90 and 6%, respectively. The protein contained all essential amino acids. The fat content ranged from 0.9 to 3.7% with a high level of the long chain polyunsaturated fatty acids EPA (eicosapentaenoic acid; 20:5n-3) and DHA (docosahexaenoic acid; 22:6n-3). Lumpfish may be a good source of B12 and D3 vitamins, however, the content of several minerals was low. The environmental pollutants and heavy metals were below the EU maximum levels, making the lumpfish safe for human consumption. Overall, our results indicate a potential to exploit the lumpfish, even after its time as a cleaner fish.publishedVersio

СРАВНИТЕЛЬНЫЙ АНАЛИЗ ОБРАЗОВАНИЯ КРИСТАЛЛОВ В ВЫСЫХАЮЩЕЙ КАПЛЕ В НОРМЕ И ПРИ ПАТОЛОГИИ

The facies of a drying drop of blood plasma of healthy and sick donors were studied. The resulting pathological structures in facies indicate certain pathological processes occurring in the patient’s body. A comparative analysis of the features of crystal formation was carried out with solutions of physiological concentrations of NaCl, glucose and protein. The method may be promising in the use of crystallography for the rapid diagnosis and prediction of a number of pathological conditions.Исследованы фации высыхающей капли плазмы крови здоровых и больных доноров. Обнаруженные в результате патологические структуры в фациях свидетельствуют об определенных патологических процессах, происходящих в организме пациентов. Сравнительный анализ особенностей образования кристаллов проведен с растворами физиологических концентраций NaCl, глюкозы и белка. Метод может быть перспективным в использовании кристаллографии для быстрой диагностики и прогнозирования ряда патологических состояний

A simulated e-commerce cold chain for fresh cod (Gadus morhua L.) products: Applicability of selected TTIs and effects of pre-treatment and packaging

The objective of this work was to study 1) the applicability of two selected time and temperature integrators (TTIs) and 2) the quality effects of different pre-treatments and packaging of fresh cod in a simulated e-commerce cold chain of 16 days. TTIs enables consumers to evaluate the product quality based on its time and temperature history. The first 6 days, the fish was either stored as gutted or gutted and filleted, representing “from business to business” (B2B), while the remaining days “from business to consumer” (B2C) value chain, the fish was packaged and stored at 4 °C in modified atmosphere (MA) or in air. One TTI recorded the temperature, and the other TTI was based on an enzymatic reaction. In B2B, the product core temperature was app. −0.5 °C. In the B2C, shelf life of 7–10 and 5–7 days for MA- and air-packaged products were obtained, respectively. Time for filleting, 1 or 6 days post-mortem for the MA products, did not influence the shelf life in the B2C. The TTI recording the temperature showed a good coherence with the reference temperature, while the reaction based TTI was inconsistent with the actual shelf life. To ensure consistency, the TTI could have been activated earlier. From a consumer's point of view, the information generated by the TTIs is beneficial to avoid the purchase of products of poor sensory quality.publishedVersio

Sammenlignende in vitro fordøyelse av fiskemuskel og kjøtt

Man vet at det gir positive helseeffekter å spise sjømat. Helsemyndigheter i mange land anbefaler at man spiser fisk minst to ganger i uken. Dette knyttes mot at fisk og fiskefett har en forebyggende effekt mot hjerte- og karsykdommer. I tillegg har det blitt observert at høyt fiskeinntak kan også føre til optimal utvikling av hjerne og nervesystem hos nyfødte, forsinket demensutvikling og forebygging mot noen kreftformer. Fiskekjøtt inneholder like mye protein som dyrekjøtt og er like god kilde for de essensielle aminosyrene. Rådene er imidlertid å begrense inntaket av rødt kjøtt og bearbeidet kjøtt. Oppbygging og den kjemiske sammensetning til muskel er ganske forskjellig hos fisk og kjøtt. Ofte hevdes det at det er tyngre å fordøye kjøtt enn fisk noe som knyttes gjerne mod det høye kollageninnholdet i kjøtt. Dette kan bidra til at fisk er sunnere enn kjøtt. Formålet med denne oppgaven var å sammenligne fordøyelsen av fiskemuskel og dyrekjøtt. I denne studien ble brukt filet fra sei (Polachius virens) og ytrefilet fra storfe (Bos Taurus). Flere interessante resultater ble funnet i oppgaven. I magesekkfasen med bruk av pepsin ved pH 4,0 var liten eller ingen frigjøring av protein eller nedbrytning av protein. Først når pH ble senket til 2,0 økte løseligheten av protein samtidig med at mengden TCA-løselig protein økte kraftig. Det ble ikke dannet frie aminosyrer i løpet av pepsinhydrolysen verken ved pH 4,0 eller 2,0. Ved høy konsentrasjon av fordøyelsesenzymer foregikk nedbrytningen av rå produkter i hovedsak i magesekkfasen. Ved lavere konsentrasjon foregikk nedbrytning av protein i større grad også i tarmfasen. Dersom man ønsker å studere nedbrytningshastighet av forskjellige typer mat vil bruk av redusert enzymkonsentrasjon anbefales. Resultatene viste at rå produkter ble brutt ned raskere i magefasen enn varmebehandlede produkter. De varmebehandlede produktene brytes i større grad ned i tarmfasen enn de rå produktene. Analyse av frie aminosyrer ble bare gjennomført på rå produkter og resultatene viste at disse dannes i tarmfasen. Forsøkene i oppgaven både med bruk av rå og varmebehandlede produkter viste at proteinene i seimuskel ble lettere brutt ned enn proteiner i storfekjøttet. Sannsynligvis skyldes dette et høyere innhold av bindevev i kjøtt enn i fisk. Dette ble også bekreftet ved analyse av aminosyreinnholdet i kjøtt og fisk. Resultatene fra aminosyreanalysene bekreftet at fisk er en god kilde for taurin sammenlignet med kjøtt

Desalting of dried salt-cured cod (Gadus morhua L.) without water renewal - 3D imaging of volume change

Desalting of dried salt-cured cod without water renewal with stirring every 12 h, and in stagnant water, was explored. Products of about 450 g were desalted for 96 h, followed by refrigerated storage in 120 h. During the desalting and subsequent storage, the change in weight, volume, salt-, and water content was calculated. Two different methods for calculation were applied, namely calculating the changes time by time, and by calculating the kinetic constants, k1 and k2, which express the total mass variation by pressure gradients, and the overall pseudo-diffusional and hydrodynamic mechanisms, respectively. A positive correlation between the change in weight, volume, and water content was observed, and these variables correlated negatively with the change in salt content. By calculating changes time by time, a significant difference in weight and salt content of the surface between the two desalting regimens was observed only after 96 h. The kinetic constants did, however, show a significant difference between the two desalting regimens for weight, salt, and water. A positive correlation between the volume and weight was observed irrespective of the desalting regimens. This indicates a future potential in applying an improved 3D imaging as an indicator of the weight changes during the desalting process.publishedVersio

Effects of Long-Term Feed Deprivation on the Development of Rigor Mortis and Aspects of Muscle Quality in Live-Stored Mature Atlantic Cod (Gadus Morhua L.)

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Gender-specific responses of mature Atlantic cod (Gadus morhua L.) to feed deprivation

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Rapport/Report 42/2016 – English summary

-Se kapittel 1 for sammendragThe aim of this study has been to evaluate new and improved systems for efficient landing of fish in Hovden, Vesterålen and Havøysund, Finnmark. The new fish on shore landing systems and technologies were evaluated in terms of how the data were registered and logged throughout the entire fish landing process. The fish factories in this study report several important reasons for implementing the new lines. Most importantly, efficient landings of fish lead to a higher quality of both fish and the by products resulting in improved profit

Desalting of dried salt-cured cod (Gadus morhua L.) without water renewal - 3D imaging of volume change

Desalting of dried salt-cured cod without water renewal with stirring every 12 h, and in stagnant water, was explored. Products of about 450 g were desalted for 96 h, followed by refrigerated storage in 120 h. During the desalting and subsequent storage, the change in weight, volume, salt-, and water content was calculated. Two different methods for calculation were applied, namely calculating the changes time by time, and by calculating the kinetic constants, k1 and k2, which express the total mass variation by pressure gradients, and the overall pseudo-diffusional and hydrodynamic mechanisms, respectively. A positive correlation between the change in weight, volume, and water content was observed, and these variables correlated negatively with the change in salt content. By calculating changes time by time, a significant difference in weight and salt content of the surface between the two desalting regimens was observed only after 96 h. The kinetic constants did, however, show a significant difference between the two desalting regimens for weight, salt, and water. A positive correlation between the volume and weight was observed irrespective of the desalting regimens. This indicates a future potential in applying an improved 3D imaging as an indicator of the weight changes during the desalting process