Flokkur: Greinar
Food quality and safety issues continue to dominate the press, with most food companies spending large amounts of money to ensure that the food quality and assessment procedures in place are adequate and produce good and safe food. This holds true for companies and laboratories responsible for the processing of fish into various products, those responsible for researching safe new products, and departments within other companies supporting these functions.
Fishery Products brings together details of all the major methodologies used to assess the quality of fishery products in the widest sense. Subject coverage of this important book includes chapters on assessment of authenticity, and several chapters on quality assessment using various methods, such as:
- Texture measurement
- Electronic nose and tongue
- NMR
- Colour measurement
This timely volume will serve as a vital tool for all those working in the processing of fishery and aquaculture products: including laboratory personnel working in regulatory bodies, food quality control personnel, food scientists, food technologists, nutritionists, seafood trade bodies, seafood labelling regulatory bodies, government food protection agencies and environmental health personnel. Libraries in research establishments and universities where food science, food technology, nutrition, aquaculture, fisheries and biological sciences are studied and taught should have copies of this important publication on their shelves.
Food quality and safety issues continue to dominate the press, with most food companies spending large amounts of money to ensure that the food quality and assessment procedures in place are adequate and produce good and safe food. This holds true for companies and laboratories responsible for the processing of fish into various products, those responsible for researching safe new products, and departments within other companies supporting these functions.
Fishery Products brings together details of all the major methodologies used to assess the quality of fishery products in the widest sense. Subject coverage of this important book includes chapters on assessment of authenticity, and several chapters on quality assessment using various methods, such as:
- Texture measurement
- Electronic nose and tongue
- NMR
- Colour measurement
This timely volume will serve as a vital tool for all those working in the processing of fishery and aquaculture products: including laboratory personnel working in regulatory bodies, food quality control personnel, food scientists, food technologists, nutritionists, seafood trade bodies, seafood labelling regulatory bodies, government food protection agencies and environmental health personnel. Libraries in research establishments and universities where food science, food technology, nutrition, aquaculture, fisheries and biological sciences are studied and taught should have copies of this important publication on their shelves.
The focus in this article is on the relation between consumer preference and objective description of the product profile of salmon. A consumer study of eight salmon products was carried out in Iceland, Denmark, the Netherlands, and Ireland. In addition, objective sensory profiling using a trained sensory panel was performed on the products, which varied according to storage method, storage time, origin, and species. For five out of eight samples, no significant differences in overall liking between the countries were found in the consumer study. However, the consumers gave the samples significantly different descriptions. There was a strong correspondence between the consumer descriptions and the sensory profile.
Quantitative descriptive analysis (QDA) was used to analyse the sensory quality of eight cod products, different with regard to origin (wild/farmed), storage time (short/extended) and storage method (fresh/frozen/packed in modified atmosphere). At the same time, 378 consumers in four European countries tasted and scored the cod products on a 9-point hedonic scale. In addition information on the consumers attitudes, motives/barriers and fish purchase behaviour was collected. The aim was to investigate how sensory quality corresponded to consumers liking of different cod products and to study the liking in terms of different consumer attitudes and demographics. The QDA discriminated well between the products. The farmed cod products were considerably different from wild cod, with more light and even colour, meaty texture, odour and flavour. Country differences were considerable with regard to fish consumption, attitudes and preferences of the eight cod products. However, it was demonstrated that within each country, different segments of consumers existed with different preferences, motives/barriers and demographic background. The results indicated various potential to increase fish consumption.
To investigate a possible speciation event within the redfish (Sebastes mentella) complex in the Irminger Sea, we examined genetics, traditional morphology, geometric morphometrics and meristics of individuals sampled throughout the Sea. Tissue samples from 1901 fish were collected in 1995 and 1996 and from 1999 to 2002, and the fish were genotyped at nine microsatellite loci, two of which were developed for this study. Individual-based genetic analyses showed that two different gene pools exist in the Irminger Sea. Although these groups overlap extensively geographically, they segregate according to depth: those above and below 550 m. This signal of genotype distinction with depth was evident in both the earlier and later sampling. Historical imprints in the genetic data indicated that the redfish in the Irminger Sea are likely to represent a case of an incipient speciation event that began in allopatry during the Pleistocene glaciations followed by secondary contact. Although hybridization was observed between groups, an analysis of traditional and geometric morphometrics and of meristic variables suggested that restricted gene flow between the currently parapatric deep- and shallow-mesopelagic incipient species may be maintained by ecological isolation mechanisms.
There are numerous parameters that can influence bacterial decontamination during washing of machinery and equipment in a food processing establishment. Incomplete de-contamination of bacteria will increase the risk of biofilm formation and consequently in-crease the risk of pathogen contamination or prevalence of other undesirable microorga-nisms such as spoilage bacteria in the processing line. The efficiency of a typical washing protocol has been determined by testing three critical parameters and their effects on bac-terial decontamination. Two surface materials (plastic and stainless steel), water tempera-tures (7 and 25 °C) and detergent concentrations (2 and 4 %) were used for this purpose in combination with two types of detergents. Biofilm was prepared on the surfaces with un-defined bacterial flora obtained from minced cod fillets. The bacterial flora of the biofilm was characterised by cultivation and molecular analysis of 16S rRNA genes. All different combinations of washing protocols tested were able to remove more than 99.9 % of the bacteria in the biofilm and reduce the cell number from 7 to 0 or 2 log units of bacte-ria/cm 2 . The results show that it is possible to use less diluted detergents than recommend-ed with comparable success, and it is easier to clean surface material made of stainless steel compared to polyethylene plastic.
Screening of potential antioxidant activities of water and 70% acetone extracts from ten species of Icelandic seaweeds was performed using three antioxidant assays. Significant differences were observed both in total phenolic contents (TPC) and antioxidant activities of extracts from the various species evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, oxygen radical absorbance capacity (ORAC) and ferrous ion-chelating ability assays. Acetone extracts from three Fucoid species had the highest TPC and consequently exhibited the strongest radical scavenging activities. High correlation was found between TPC of seaweed extracts and their scavenging capacity against DPPH and peroxyl radicals, indicating an important role of algal polyphenols as chain-breaking antioxidants. However, water extracts generally had higher ferrous ion-chelating activity than 70% acetone extracts and no correlation was found with their TPC, suggesting that other components such as polysaccharides, proteins or peptides in the extracts were more effective chelators of ferrous ions than phenolic compounds.
Aims: The genetic diversity of Campylobacter isolated from human infection and from poultry was assessed in strains originating in three different European regions in order to compare these two hosts and to investigate European regional differences.
Methods and Results: Randomly chosen isolates originated from Norway, Iceland and Basque Country in Spain were genotyped by sequencing of the short variable region (SVR) of flaA. A total of 293 strains were investigated, c. 100 per country with half originated from either host. The results indicate extensive diversity in both hosts and identified differences in the nature and distribution of genotypes between the countries. These differences could in part be related to geographical location, in that Campylobacter genotypes from Iceland and Norway were more similar to each other than either was to Basque Country.
Conclusions: Differences between the countries exceeded the observed differences between human and poultry isolates within a country.
Significance and Impact of the Study: Regional differences are extensive and should not be ignored when comparing genotyping data originating from different international studies.