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To provide a comprehensive overview of the amounts of unesterified and bound 2- and 3-monochloropropanediol (MCPD) and glycidyl esters (G–E) in processed fishery products sold in Germany, an analysis of various frequently consumed products was conducted. In total, 258 commercial samples of breaded and pre-fried fishery products (e.g., frozen fish fingers), fried fish products (e.g., products in marinade), canned fish, smoked fish and some smoked spice preparations were examined. In addition, the effect of different kitchen preparation methods (e.g., baking, frying and roasting) on the MCPD and G–E amounts of fish fingers was studied. The mentioned process contaminants, MCPD and G-E, were quantifiable in the majority of the samples. Although pre-fried and fried fishery products predominantly contained MCPD esters (MCPD-E), mainly free MCPD was found in smoked fish. Compared with other types of smoke generation, hot smoked fish prepared in traditional Altona smoking kilns contained, on average, the highest 3-MCPD contents (range: 12–246 µg/kg). The amounts of bound MCPD in the fried fish products (range for 3-MCPD-E

Anisakid nematode larvae (NL) in fish products comprise a risk to human health and, if visible, lead to the rejection of these products by consumers. Therefore, great efforts are being made for the identification of these anisakid larvae to estimate the potential consumer health risk as well as to develop effective detection methods in order to prevent the introduction of heavily infected fish products into the market. The tasks of national reference laboratories include the improvement of detection methods and to promote their further development. As a prerequisite for improved detection, it is important to understand the structural properties of anisakid NL and compounds produced during host-parasite interactions. This review provides an overview of the intrinsic properties of anisakid NL and reports the latest detection methods in published literature. First, in order to define the potentially interesting intrinsic properties of anisakid nematodes for their detection, anatomy and compounds involved in host-parasite interactions are summarised. These can be used for various detection approaches, such as in the medical field or for allergen detection in fish products. In addition, fluorescence characteristics and their use as both established and promising candidates for detection methods, especially in the field of optical sensing technologies, are presented. Finally, different detection and identification methods applied by the fish processing industries and by control laboratories are listed. The review intends to highlight trends and provide suggestions for the development of improved detection and identification methods of anisakid NL in fish products.

Canned liver is a highly valuable and healthy product from the important commercial fish species cod Gadus morhua. Due to high levels of contaminants such as dioxins and dioxin-like PCBs (polychlorinated biphenyls) in cod liver products from the Baltic Sea, the grounds for supply of cod liver were relocated to areas around Iceland in the Irminger Sea with lower levels of contaminants. In the present study, 62 canned samples, as well as 132 fresh cod livers from Greenland and Iceland, were analysed in order to assess the infection levels with anisakid nematode species. High prevalence and abundance of the potentially zoonotic nematode species Anisakis simplex s.s. and Pseudoterranova decipiens s.s. were found in the fresh livers. Lower infection levels in canned livers compared to fresh livers might indicate successful industrial processing measures in order to reduce nematode larvae in the final products. However, two heat stable allergens, Ani s 1 and Ani s 4, were verified from isolated nematode larvae from canned products. The effectiveness of methods to further reduce the number of nematode larvae during industrial processing of cans with cod liver is discussed.

Beaked redfish (Sebastes mentella) and Greenland halibut (Reinhardtius hippoglossoides) were collected from fishing grounds of the Barents Sea to study the composition and lipid distribution of the muscle tissue. The belly flaps of beaked redfish showed higher lipid contents (mean 4.6%) compared to anterior dorsal muscle. The protein content was relatively constant in all parts (18–19%). The variation in the muscle lipid composition among individual redfish was greater than the variation among different anatomical locations of the fillets. No significant differences were found in the composition of Greenland halibut muscle parts. The protein content was generally low and ranged between 12.2–13.9%. The lipid content varied considerably between approximately 6 and 17%, displaying large variations of the lipid contents between different Greenland halibut individuals from one catch. The variability of lipid content should be considered in the risk assessment and management of lipophilic contaminants in fish fillets. A correlation between water and lipid content was found for both species (r = −0.8750, beaked redfish; r = −0.8732, Greenland halibut).

Pre-frying of chloride-containing raw materials (e.g., breaded frozen fish products) can lead to the formation of fatty acid esters of 2-monochloropropane-1,3-diol, 3-monochloropropane-1,2-diol (MCPD-E), and glycidol (G-E). The aim of the present study was to identify relevant parameters for the formation of these process contaminants during the pre-frying. Secondly, several mitigation approaches have been investigated. The major proportion of the MCPD-E and G-E in the fish products resulted from the pre-frying oil absorbed, while the temperature and the heating period of the pre-frying oil showed the strongest impact. A significant reduction of the MCPD-E content in the pre-frying oil was achieved by filtering-off solid breading particles. Additionally, the G-E content decreased resulting from the use of adsorbent materials. Moreover, the analyses of total polar material and the color intensity of the pre-frying oil are suggested as screening methods for estimating the MCPD-E and G-E contents in the fish products.

Nile perch ( Lates niloticus ) is a popular, usually low priced food fish in many countries worldwide, and the most important export fish from Lake Victoria and its adjacent countries Uganda, Tanzania and Kenya. Despite its high import figures, the constantly increasing demand within the EU for ‘new’ fish species and the results of initial studies indicating high coliform bacterial loads, food safety aspects regarding its microbiological as well as parasitological status have been hitherto widely neglected. In the present study imported fresh fish fillets as well as superchilled fish from a German retail market and a Dutch wholesaler were examined to evaluate the current microbiological and parasitological quality. A total of 200 fresh fillets as well as 20 superchilled fish (beheaded, eviscerated, descaled) samples were screened for the presence of helminth parasites by visual inspection, candling, the UV-press method and artificial digestion method. The study includes as well a quantitative test on the recovery rate of metacercarial cysts. Microbial assessment was performed on ten fresh fillets and on the skin and tissue of 20 superchilled fish. Helminth parasites were neither detected in the edible parts nor in the skin of imported products. Results of the microbiological examination revealed low levels of bacterial contamination of superchilled fish samples, whereas high total viable counts and high levels of naturally present bacterial pathogens of the genus Aeromonas spp. and Pseudomonas spp. were identified from the fresh fillets. Our findings indicate that hygienic production conditions have improved in comparison to previous studies. As total viable counts as well as specific spoiling bacteria were high in fresh fillets, we recommend adequate heat treatment of fresh Nile perch fillets before consumption.

Fish and fish oil are an important source of essential dietary components such as polyunsaturated long chain fatty acids like eicosapentaenoic acid and docosahexaenoic acid. Refining of crude fish oil is necessary to remove environmental contaminants e.g., dibenzo- p -dioxins, dibenzofurans, dioxin-like polychlorinated biphenyls, and non-dioxin-like polychlorinated biphenyls for reaching legal limits, ensuring a pleasant taste and for enhancing shelf-life. However, during the deodorization of crude fish oil, process contaminants such as 2- and 3-monochloropropane-diol esters and glycidyl esters may be formed. The aim of the present study was to provide a comprehensive overview on the content of selected environmental and process contaminants in raw and processed fish oils deriving from different fish species. In crude fish oils extracted from farmed fish, the contents of environmental contaminants were well below the legal limits for food grade fish oil. In contrast, fish oils extracted from captured fish did not meet the requirements for human consumption. When applying filtration over active carbon, a reduction in the content of dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls was achieved. 2- and 3-monochloropropane-diol ester and glycidyl ester contents were considerably higher in the refined compared to the crude fish oils investigated. Additionally, the comparison of analyzed and labeled contents of polyunsaturated long chain fatty acids showed a satisfying compliance.

PurposeTo compare manual corrections of liver masks produced by a fully automatic segmentation method based on convolutional neural networks (CNN) with manual routine segmentations in MR images in terms of inter-observer variability and interaction time.MethodsFor testing, patient's precise reference segmentations that fulfill the quality requirements for liver surgery were manually created. One radiologist and two radiology residents were asked to provide manual routine segmentations. We used our automatic segmentation method Liver-Net to produce liver masks for the test cases and asked a radiologist assistant and one further resident to correct the automatic results. All observers were asked to measure their interaction time. Both manual routine and corrected segmentations were compared with the reference annotations.ResultsThe manual routine segmentations achieved a mean Dice index of 0.95 and a mean relative error (RVE) of 4.7%. The quality of liver masks produced by the Liver-Net was on average 0.95 Dice and 4.5% RVE. Liver masks resulting from manual corrections of automatically generated segmentations compared to routine results led to a significantly lower inter-observer variability (mean per case absolute RVE difference across observers 0.69%) when compared to manual routine ones (2.75%). The mean interaction time was 2 min for manual corrections and 10 min for manual routine segmentations.ConclusionsThe quality of automatic liver segmentations is on par with those from manual routines. Using automatic liver masks in the clinical workflow could lead to a reduction of segmentation time and a more consistent liver volume estimation across different observers.

Regarding cod as sea food for human consumption and as bio indicator of the marine eco system, this study is the first approach to combine the analysis of organic and inorganic contaminants and radionuclides in cod muscle as well as PCDD/Fs and dl-PCBs in its livers from the same fishing areas. Concentrations of 1-hydroxypyrene, PCDD/Fs, PCBs, cesium-137 (Cs-137), cadmium and lead were determined in individual or pooled samples over a wide geographic area, including Greenland Seas, Barents Sea, North and Baltic Sea. Highest concentrations were found in samples from the Baltic Sea, lowest in the pristine areas of the Barents Sea and Greenland. Levels of contaminants in cod muscle were found to be far below the established EU maximum levels (ML), regardless of which fishing grounds. In contrast to this, most cod liver samples from the North and Baltic Sea showed PCDD/F and PCB contents exceeding the ML. In addition, new background assessment criteria (BAC) for 1-hydroxypyrene in cod of 4.6 ng mL(-1) bile and for Cs-137 a BAC of 0.16 Bq kg(-1) wet weight are proposed to be included in the European Marine Strategy Framework Directive for cod from the Northeast Atlantic.

Beaked redfish (Sebastes mentella) and Greenland halibut (Reinhardtius hippoglossoides) were collected in waters around Svalbard (Barents Sea) to study the influence of different muscle separation/filleting techniques at small and medium fishes on the dioxin/PCB content. Sampling of both species included preparation techniques such as fillets with or without belly flaps, commercially trimmed fillets and cutting into anterior and posterior cutlets. In case of Greenland halibut also the whole edible muscle part and middle cutlets were studied. All samples analysed were far below the maximum level of 6.5 pg/g wet weight (ww) WHO-PCDD/F-PCB-TEQ and 75 ng/g ww ndl-PCB. Trimmed fillets of beaked redfish had the lowest fat content and the lowest level of dioxins and PCB (1.70%, WHO-PCDD/F-PCB-TEQ = 0.320 pg/g ww). The respective posterior cutlets showed the highest fat content and highest levels of dioxins and PCB (2.66%, WHO-PCDD/F-PCB-TEQ = 0.729 pg/g ww). Levels of dioxins and PCB in Greenland halibut samples were generally higher and ranged between WHO-PCDD/F-PCB-TEQ = 0.784 pg/g ww (fillets without bells flaps, fat content = 8.83%) and WHO-PCDD/F-PCB-TEQ = 2.022 pg/g ww (edible part whole muscle, fat content = 8.62%). The results show a considerable influence of the different sampling methods on the dioxin and PCB levels of the species analysed.

Automatic liver tumor segmentation would have a big impact on liver therapy planning procedures and follow-up assessment, thanks to standardization and incorporation of full volumetric information. In this work, we develop a fully automatic method for liver tumor segmentation in CT images based on a 2D fully convolutional neural network with an object-based postprocessing step. We describe our experiments on the LiTS challenge training data set and evaluate segmentation and detection performance. Our proposed design cascading two models working on voxel- and object-level allowed for a significant reduction of false positive findings by 85% when compared with the raw neural network output. In comparison with the human performance, our approach achieves a similar segmentation quality for detected tumors (mean Dice 0.69 vs. 0.72), but is inferior in the detection performance (recall 63% vs. 92%). Finally, we describe how we participated in the LiTS challenge and achieved state-of-the-art performance.

In the present study, existing official methods for oils were modified in order to analyze free and bound MCPD and bound glycidol in fish. Free 3-MCPD was determined in aqueous extracts of fishery products. DGF standard methods C-VI-17(10) and C-VI-18(10) and the 3 in 1 method were modified and tested to quantify ester-bound 2- and 3-MCPD and glycidyl esters. The different methods were validated using spiked fish mince and a naturally contaminated reference material consisting of homogenized smoked sprat and fish sticks. The methods showed good agreement. Assay B of the modified DGF method C-VI-18(10) and the adapted 3 in 1 method allow a quantitative determination of bound 2- and 3-MCPD in fishery products. In addition, glycidyl esters can be quantified applying the 3 in 1 method. The screening of various fishery products showed that smoked fish may contain considerable amounts of free 3-MCPD. Concentrations ranged between 8 and 388mg/kg wet weight (ww). Only traces of free 3-MCPD were found in all other fishery products. Fish sticks and fried fish products are potential sources of 3- and 2-MCPD esters, but large variation were observed. Bound 3-MCPD ranged between 45 and 377mg/kg ww, bound 2-MCPD between 9 and 116mg/kg ww. Practical applications: The European Food Safety Authority (EFSA) is calling for occurrence data of 2-MCPD, 3-MCPD, 2-MCPD ester, 3-MCPD ester, and glycidyl ester in foods including fishery products. At present, there is no official method for the determination of these food processing contaminants in fish and fishery products. Therefore, the approach of this study was to establish analytical methods for the quantification of free and bound MCPD and bound glycidol in fish, based on the modification of existing methods for edible oils. The adapted methods allow a sensitive quantitative determination of the target analytes in various fishery products.

Parasitic anisakid nematodes commonly occur in the musculature and visceral organs of many fish species from the North Atlantic. In this respect, the presence of the third stage larvae of Anisakis spp. in the fish musculature may pose a potential consumer hazard due to the parasite's ability to cause anisakidosis. Thus, knowledge on the occurrence and distribution of these potentially zoonotic parasites in the commercially important North Atlantic fish species is crucial in order to evaluate and consequently prevent human infections. In the present study, 300 Sebastes mentella from three North Atlantic fishing grounds (Northern North Sea: Tampen; Barents Sea: off Bear Island; Irminger Sea: off SE Greenland) were examined for anisakid nematodes, with emphasis on occurrence and distribution in the musculature. Overall larval prevalence and mean intensity were significantly higher in redfish from Tampen (94%; 13.5±20.0) and Bear Island (94%; 14.5±19.4) than in fish from SE Greenland (75%; 6.0±5.8; p0.01). The same trend was observed for larval infection in the musculature showing prevalence and mean intensities of 79%, 73%, and 55%, and 5.9±6.6, 5.8±6.5, and 3.2±2.4, in the musculature of redfish from Tampen, Bear Island, and Greenland, respectively. Conventional microscopy and rDNA ITS-gene sequencing of various subsamples of muscle-dwelling nematode larvae of redfish from every catching locality revealed the presence of two anisakid species; Anisakis simplex sensu stricto and the non-zoonotic Hysterothylacium aduncum. Since the larvae of H. aduncum typically occur in or on the viscera of fish, our findings of two specimens in the belly flaps of redfish were unusual. Additionally, more than 92% of the muscle-dwelling larvae occurred in the belly flaps, i.e. the hypaxial part of the musculature surrounding the visceral organs on either fish side. Thus, trimming the fillets of beaked redfish by removal of most of the belly flaps would significantly reduce the probability of anisakid nematode larvae to be present in the final product.

A collaborative study for quantification of Anisakis larvae in spiked farmed salmon fillets was conducted by 12 laboratories in 2012, using a modified Codex method (CODEX STAN 244). N = 6 samples with a different number of Anisakis larvae including two blind duplicates were analyzed by participants. All laboratories applied the same modified digestion method with stirring speed of 500–600 rpm, using a triangular stirring bar and a maximum digestion temperature of 35 °C in order to reduce fragmentation of larvae. All participants found correctly no larvae in the control samples while the mean recovery rate of all spiked larvae was 86.6 %. The among-laboratory reproducibility was 16.5 %. Differences were noticed in the interpretation of Anisakis fragments, which occurred as a result of prolonged frozen storage of the samples.

Summary Proximate composition, fatty acid profile, other nutritional values and spoilage indicators were examined in the muscle meat of five species: barramundi (Lates calcarifer) from various origins, tilapia (Oreochromis spp.) of different qualities, cobia (Rachycentron canadum) and leather jacket (Aluterus monoceros) from the Pacific Ocean and Patagonian grenadier (Macruronus magellanicus) from South America. Lowest lipid contents (0.4% and 0.8%) were found in leather jacket and cobia. Leather jacket fillets had lowest protein (16.2%) and highest sodium chloride content (4.9%). Concentrations of ∑EPA + DHA were 0.1 g 100 g−1 for tilapia and leather jacket, 0.2 g 100 g−1 for barramundi and cobia and 0.7 g 100 g−1 for Patagonian grenadier. Barramundi and tilapia were characterised by high taurine content (215 and 276 mg 100 g−1 ww.), and cobia had only low levels (41 mg 100 g−1 ww.). Iodine contents were low and selenium levels varied between 303 and 570 μg kg−1 ww. No sign of spoilage was detected.

Previous studies have shown that Grey gurnard from the North Sea is comparatively heavily infected with the larvae of the parasitic and potentially consumer hazardous nematode Anisakis simplex (s.l.). Especially the high abundance of Anisakis larvae in the fish flesh is of concern regarding the possible intensified utilisation of Grey Gurnard as a food resource. To gain better knowledge of the nematode burden with emphasis on abundance and distribution in the fish flesh, various Grey gurnards from 6 localities across the North Sea, each representing either western, northern or eastern fishing grounds, were examined for anisakid nematodes during summer of 2010 and 2012. The overall prevalence of A. simplex (s.l.) larvae in the gurnards from all localities (n = 188) was nearly total, i.e. only a single fish from the northernmost locality (Viking Bank) was apparently not infected. GLM-analyses revealed that catching locality had by far the strongest effect on larval infection probability, both in total (flesh + viscera) and in the fish flesh, while body size (weight) was a weak but still significant predictor of overall A. simplex (s.l.) abundance, but not in the flesh. Thus, the overall larval abundance in the gurnards from the two western localities off the east-coast of British mainland was significantly higher compared to the other catching localities. In the former localities, the overall mean abundance of A. simplex (s.l.) larvae was 35.0 ± 23.9 and 92.2 ± 87.4, and ranged from 14 to 114 and 9 to 397, respectively. It was further shown that 93.8% of the larvae infecting the fish flesh were situated in the belly flaps, i.e. the ventral portion of each flesh side or fillet, independent of catching locality and fish size. However, trimming of the fillets by removing the belly flaps may reduce the abundance in the fillets to, on an average, 0.3 larvae.

This study discusses the various factors which influence the intake of dioxins and dioxin-like PCBs (dl-PCBs) via fish consumption to support the requirements for additional information for an adequate estimation of consumer’s exposure. Growing consumer preferences towards lean and aquaculture species have to be considered in future. The varying dioxin and dl-PCB levels of herring in relation to the geographical origin and the fishing season and their consequences for the estimation of the exposition are discussed. The levels in herring from different fishing grounds can vary by a factor of 8 between 0.43 and 3.04 ng WHO–PCDD/F–PCB–TEQ2005/kg wet weight. Increasing lipid content of the muscle meat during the feeding cycle of herring and mackerel leads to a “dilution effect” of contaminants based on lipid weight. Changes in the composition of feed for carnivorous species reduced the dioxin levels in farmed salmon and trout considerably between 1997 and 2004. Hence only recently taken data collections should be used for exposure estimation. Furthermore processing and household preparation can change the contaminant levels and should be taken into account.

Summary Proximate composition, fatty acids profiles and other nutritional values were evaluated for fillets of Limanda aspera (yellowfin sole), Lepidopsetta bilineata (southern rock sole) and Lepidopsetta polyxystra (northern rock sole) and compared to North Sea plaice (Pleuronectes platessa). Additional information is given on the composition of fillets from arrowtooth flounder (Atheresthes stomias). Plaice (0.8% lipid) and Alaska soles (1.0–1.2% lipid) can be classified as lean species, resulting in low 0.3–0.5 g ∑EPA+DHA/100 g muscle, although the fatty acid profiles of the extracted lipids were characterised by high amount of n-3 fatty acids (33.2–47.3%). Arrowtooth flounder belong to the medium-fat species (4.3%). Taurine was the most prevalent free amino acid; mean values ranging between 221 mg100 g−1 and 247 mg100 g−1 wet weight. The selenium content varied between 130 and 310 μg kg−1 ww. Sensory attributes of Southern and Northern rock sole were comparable to plaice.

Lipid determination by the Smedes method was tested in an interlaboratory trial performed by nine laboratories from seven countries belonging to the West European Fish Technologists Association Analytical Methods Working Group. Five samples of fish and fishery products with different lipid contents, including two blind duplicates, were distributed among the participants. All laboratories applied a slightly modified Smedes method, which included extraction of lipids by cyclohexane and isopropanol, transfer of lipids to the cyclohexane phase by addition of water, phase separation by centrifugation, and gravimetric lipid determination. The results indicate that the RSD for reproducibility (RSDR) was between 4.11 and 6.31% for samples with moderate (7%) and high (14%) lipid content, depending on the sample. Larger SDs among the laboratories were obtained for a cod sample with low lipid content of 0.5%. The method is judged to be suitable as a routine method for lipid determination in fish and fishery products.

140 Milcherzeugnisse aus verschiedenen Regionen Deutschlands wurden 2006 auf Dioxine, dioxinahnliche PCB und nicht dioxinahnliche PCB untersucht. Insgesamt wurden 66 Kase-, 23 Butter- und 51 Quark- bzw. Joghurterzeugnisse analysiert. Die Probenahme erfolgte in Supermarkten und Einzelhandelsgeschaften auf der Basis der Produktionsmengen in den einzelnen Bundeslandern der Bundesrepublik Deutschland. Die Dioxinkonzentrationen und die Summe der WHO-TEQ blieben weit unter den EU-Grenzwerten von 3 pg WHO-PCDD/F-TEQ/g Fett und 6 pg WHO-PCDD/F-PCB-TEQ/g Fett. Die Dioxingehalte lagen bei niedrigen 0,07–0,53 pg WHO-PCDD/F-TEQ/g Fett mit einem arithmetischen Mittelwert von 0,19 pg WHO-PCDD/F-TEQ/kg Fett. Die WHO-PCDD/F-PCB-TEQ Gehalte lagen zwischen 0,21 und 2,1 pg WHO-TEQ/g Fett, mit einem mittleren Gehalt von 0,76 pg WHO-TEQ/g Fett. Regionale Abhangigkeiten und Unterschiede zwischen den einzelnen Produktgruppen konnten nicht festgestellt werden. Langjahrige Messungen der Dioxingehalte in Butter und Kase aus Schleswig-Holstein zeigen uber den Zeitraum von 13 Jahren eine deutliche Abnahme der Gehalte von 0,43 auf 0,19 pg WHO-PCDD/F-TEQ/g Fett.

Grey gurnard ( Eutrigla gurnardus L.) is an abundant and widely distributed demersal fish in the North Sea. It is currently considered a sustainable stock, thus permitting future increased utilisation as a food resource. In order to address both consumer safety and aesthetical product quality, the occurrence and distribution of anisakid nematode larvae in Grey gurnard from two localities in the North Sea were investigated. Two anisakid species were recorded, i.e. Hysterothylacium aduncum in the viscera, and Anisakis simplex in both the viscera and flesh of the fish. Virtually all gurnards were infected with nematode larvae. However, H. aduncum was significantly less abundant than A. simplex in the fish from both localities. Only for the gurnards from the northernmost sampling locality there was a significantly positive correlation between host body weight and total A. simplex abundance. No such correlation was found for H. aduncum in either locality. Separate analyses of the Anisakis infection data in gurnards of marketable size (≥250 g) and pooled for both localities, revealed 83% prevalence of A. simplex larvae in the fish flesh, ranging 1–16 in intensity. The relative larval distribution between the viscera and flesh was 89 and 11%, respectively. Moreover, a significantly positive correlation was found between A. simplex occurring in the viscera and the flesh of this particular host size group, i.e. the number of larvae in the flesh appeared to increase with increasing infection level in the viscera. In general, Grey gurnard from the North Sea can be considered as heavily infected with nematode larvae. Especially the comparatively high abundance of A. simplex larvae in the flesh is of concern regarding the possible intensified utilization of Grey gurnard as a food resource.

The study of the beryciform Anoplogaster cornuta from the Irminger Sea (north Atlantic) revealed the presence of the anisakid nematode Anisakis paggiae inside the body cavity, representing a new host and locality record. This deep-sea fish was infected with Anisakis larvae at a prevalence of 57.1% and a mean intensity of 2.2, with no correlation between the fish standard length and the number of accumulated A. paggiae. Kogiid whales (Kogia breviceps, K. sima), the typical final hosts of this parasitic nematode, have not yet been recorded so far in the north. Because A. cornuta does not migrate outside the Irminger Sea, and by using the parasite as an indicator for the presence of the final hosts, A. paggiae must have been introduced through migratory kogiid final hosts. This would extend their range of distribution into the Irminger Sea. The depth range of the meso- and bathypelagic A. cornuta and the frequent occurrence of Anisakis inside this deep-sea fish demonstrate an oceanic deep-water life cycle for A. paggiae in the north Atlantic.

Up to now the visual inspection of mobility of isolated anisakid larvae serves as a measure of viability and possible risk of infection. This paper presents a new method to rule out unreliability – caused by the temporary immobility of the larvae and by the human uncertainty factor of visual observation. By means of a Near infrared (NIR) imaging method, elastic curvature energies and geometric shape parameters were determined from contours, and used as a measure of viability. It was based on the modelling of larvae as a cylindrical membrane system. The interaction between curvatures, contraction of the longitudinal muscles, and inner pressure enabled the derivation of viability from stationary form data. From series of spectrally signed images within a narrow wavelength range, curvature data of the larvae were determined. Possible mobility of larvae was taken into account in statistical error variables. Experiments on individual living larvae, long-term observations of Anisakis larvae, and comparative studies of the staining method and the VTD measurements of larvae from the tissue of products confirmed the effectiveness of this method. The VTD differentiated clearly between live and dead nematode larvae isolated from marinated, deep-frozen and salted products. The VTD has been proven as excellent method to detect living anisakid nematode larvae in fishery products and is seen as useful tool for fish processing industry and control authorities.

A range of conventionally and organically farmed Pangasius or sutchi catfish fillets available on the German market were analysed to compare both composition and quality. Differentiation of Pangasius hypophthalmus from Pangasius bocourti was achieved by RFLP-SSCP analysis. The protein content of conventionally farmed fillets ranged between 13.3 and 15.7%, whereas organically produced fillets had significantly higher protein contents of between 17.0 and 17.4%. No difference in the fat content between farming methods was observed, which varied between 1.4 and 3.2%. Polyunsaturated fatty acids represented about 24% of the total fatty acids with a high level of linoleic acid. The comparison of the proximate composition indicated that water was added to most of the conventionally farmed products, in different amounts, as well as water-binding capacity enhancing additives. Differential scanning calorimetry was used to demonstrate the presence of polyphosphate on muscle proteins. Differences in texture, water-binding capacity and colour are discussed.

The contaminant levels of dioxins, dioxin-like PCBs and non dioxin-like PCBs were determined in pooled samples of cod liver and corresponding cod muscle from different fishing grounds of the North- and Baltic Sea and from East Greenland. The dependence of the contaminant concentrations was studied on cod of three different sizes caught at the same fishing ground. Samples were taken during different research trips at 11 fishing grounds of the Baltic Sea, and 3 fishing grounds of the North Sea and of East Greenland in 2006 and 2007, respectively. Cod liver from the Baltic- and the North Sea were highly contaminated. Mean concentrations were 93 and 83 ng WHO-TEQ/kg wet weight (w.w.), respectively. Cod livers from East Greenland had only low contaminant levels of 3.4 ng WHO-TEQ/kg w.w. Highest concentrations were found in livers from the Bay of Kiel. Within the same fishing area the concentrations increased with the size of the cod. The WHO-TEQ amounts of the cod fillets were below 1 ng WHO-TEQ/kg w.w. and thus within the commonly observed low range for lean fish.

Concentrations of polychlorinated dibenzodioxins, dibenzofurans and dioxin-like PCBs in the edible part of fish and in fishery products were studied to gain an overview on actual contaminant levels on the German market.

The survival of Anisakis sp. larvae in herring fillets marinated in brines with different concentrations of salt (NaCI) and acetic acid was examined. Traditional German and Danish procedures for marinating herring fillets require a storage time of at least 5 and 6 weeks, respectively, for all larvae to be killed. Other concentrations of salt and acetic acid were also studied. A reduction of the salt content in the water phase of the fish tissue from 9% (w/w) to 4.3% (w/w), while keeping the concentration of acetic acid constant at 2.6%, increased the survival time of the nematodes from at least 35 days to more than 119 days. Increases in the acetic acid concentration or the addition of potassium sorbate had little or no effect on the viability of the larvae.

Fish among meat and dairy products mainly contribute to the human exposition with dioxins and dioxin-like PCBs. Contaminant levels of fish are mainly determined in the edible part of the raw material. In Germany fish are not consumed raw but industrially processed to manifold products and cooked, fried or deep-fried in household. To study the influence of processing on the contaminant levels, changes of dioxins and partly of dioxin-like PCBs were followed during canning of herring fillets, hot smoking of mackerel fillets and Greenland halibut cutlets and during sugar salting of beheaded whole herring. The hot smoking process and sugar salting of herring led to an increase of the dioxin content in the edible part of the final product. The increase was related to the loss of water during processing whereas the fat and thus the lipophilic dioxins remained in the muscle meat. For sugar salting also changes of dioxin-like PCB levels were followed and the same effect was observed. Otherwise the production of canned herring fillets in tomato sauce led to a “dilution” of the dioxin content due to the addition of the sauce.

Comparative ice storage experiments were performed to study the influence of early gutting on the shelf life of gutted and ungutted saithe, plaice and haddock. The investigation included the rating of the external quality attributes according to the EU-quality grading scheme, the sensory assessment of cooked fillets, the chemical analysis of changes in the contents of the total volatile bases (TVB), trimethylamine (TMA) and dimethylamine (DMA), of total viable counts (TVC) and the number of specific spoilage bacteria (SSO) Shewanella putrefaciens on skin and tissue samples.

Tilletia caries is a fungus that mainly infects wheat, causing the disease bunt. Wheat bunt had been one of the most dangerous plant diseases before seed dressing was a common practice. However, it is still of importance in organic farming, since seed dressing is not permitted. Trimethylamine (TMA) is a metabolic product of T. caries known to cause a fishy odour of highly contaminated wheat. Therefore, contamination of feed is supposed to decrease feed intake. However, systematic studies on the effect of practically relevant proportions of bunt-infected wheat on performance and health of pigs are not available. Therefore, the aim of the present study was to investigate the effects of increasing proportions of bunt-infected wheat (0%, 10%, 20% and 30% of the diet) corresponding to a total spore content of 0%, 0.2%, 0.4% and 0.6% on the performance and health of piglets during a 5-week experiment starting after weaning. TMA was not detectable in the contaminated wheat and the feed intake of piglets remained unaffected. However, live weight gain decreased linearly and feed-to-gain ratio significantly increased as the proportion of contaminated wheat increased. Haematological and serum clinical-chemical characteristics as well as the viability of peripheral blood mononuclear cells were not influenced by dietary treatments. Based on the limited data of the present experiment it might be concluded from the adverse effects of bunt-infected wheat in piglet diets on the feed-to-gain ratio that a spore content of 0.2% of the complete diet should not be exceeded.

The distribution of Anisakis larvae in fresh caught hake was studied, and the influence of three infection levels of the viscera (low, medium, high) on quality changes of deep frozen muscle was followed over 220 days. Differences in quality were attributed more to the size of the individuals than to the infection degree of the three groups. The removal of belly flaps diminished the risk of consumers infection and sensitization as prevalence and intensity was reduced to 75.6 and 5.9%, respectively. Allergens were detected after 220 days frozen storage, which represents a risk for consumers already allergic to Anisakis., This work was partly financed by the Spanish projects AGL2005-05699-C02-01/02 and AGL2009-12485-C03-01/03

Three toxaphene indicator compounds were determined in fish oil and fish meal of different origin and raw material as well as in feed containing fish oil and fish meal. Fish oil and fish meal from South America contained no or only traces of the indicator congeners. The sum of the three compounds varied in fish oils from Europe between 13 micrograms/kg fat (sand eel oil) and 206 micrograms/kg fat (cod oil). Varying concentrations were also determined in European fish meal and in feed. Toxaphene indicator compounds were as well detected in trout and salmon fed with toxaphene residues containing feed. Results indicate that feed can contribute to toxaphene contamination of farmed salmon from Europe.

Cis-, trans-, oxychlordane and trans-nonachlor were determined in the edible part of more than 140 fish samples of 15 different species and in fish meal, -oil and fish feed. The investigated fish included most of the important fish species consumed in Germany. Highest concentrations were found in muscle of marine fish with high or moderate fat content, but also in eel and farmed salmon. Marine fish with low fat content contained only traces of chlordane in the muscle tissue. A relationship between fishing ground and levels of chlordane could not be established. Contamination level of herring was related to the age (length) of the fish. Data are also given for contamination levels of fish meal, -oil and -feed.

Three toxaphene indicator compounds were determined in more than 100 samples of fish. The investigated fish included nearly all important fish species consumed in Germany. Highest residue concentrations were found in marine fish with high or moderate fat content, e.g. halibut, herring, redfish and mackerel. In fresh water species and marine fish with low fat content less contamination was found. A significant relationship between the fishing ground and the toxaphene residue could not established. Contamination levels of most species were related to the age (length) of the fish. The daily intake of total toxaphene in Germany was estimated at 2.8–5.6 ng/kg body weight.

European smelt Osmerus eperlanus (n = 501) from the German Wadden Sea (North Sea) near the city of Cuxhaven were examined for their infestation with parasitic anisakid nema- todes, especially with sealworms of the genus Pseudoterranova. The distribution of third-stage lar- vae (L3) in the musculature and viscera of the fish was analyzed. In total, we isolated 543 L3 from the hosts' body cavity and musculature. A subsample of 105 larvae were identified as the (sibling) species P. decipiens s.s. using direct sequencing of the highly variable ribosomal ITS1-5.8S-ITS2 genetic marker. The mean abundance was 1.1, the mean intensity was 2.3 P. decipiens s.s. and the prevalence was 47.3%. Total length and total weight, but not Fulton's condition factor (K), were significantly different in infected compared to uninfected smelt. No correlation was found between the total length of infected fish and the intensity of anisakid nematodes. The vast major- ity of P. decipiens s.s. was found in the musculature of the smelt. More than half (55.7%) of all nematodes were located in the 3 parts of the epaxial musculature, whereas 18.4 and 26.0% were found in the hypaxial musculature and the compartments of the tail muscles, respectively.

The prevalence, mean intensity and distribution of Anisakis nematode third-stage larvae (L3) in the muscle and viscera of wild-caught chum salmon Oncorhynchus keta, pink salmon O. gorbuscha and sockeye salmon O. nerka were compared immediately after catch. Salmon were collected during the fishing season in July 2007 in Bristol Bay and Prince William Sound close to Cordova, Alaska (USA). All fish were infected, and more than 90% of the nematode larvae were found in the edible muscle meat. The isolated anisakid L3 were genetically identified as A. simplex (s.s.). The distribution of nematodes in the muscle meat of fresh-caught salmon was examined in 49 O. keta, 50 O. nerka and 12 O. gorbuscha from Cordova. Most of the larvae were detected in the muscle parts around the body cavity, but nematodes were also found in the tail meat and epaxial muscle (loins). The mean intensity of Anisakis larvae in the edible part was 21 individuals for O. gorbuscha, 62 individuals for O. keta and 63 individuals for O. nerka. No difference in the intensity of Anisakis larvae in the hypaxial muscle was found between fresh-caught and immediately gutted salmon and individuals stored ungutted for 24 h either on ice or in refrigerated sea water.

Fifty-four eel samples from 11 different countries were analysed by capillary gas chromatography for levels of the pesticides aldrin, endrin, hexachlorobenzene, alpha- and beta-BHC, lindane, heptachlor, octachlorostyrene, pp'-DDT, pp'-DDD, pp'-DDE, and for the levels of the PCB congeners 28, 52, 101, 138, 153, and 180. Wild eels, especially from the Baltic Sea area, had elevated contents compared to farmed eels. The mean contamination level reached only 1-5% of the allowable values given by German directives and never exceeded the official limits.

The behavior of larvae of Anisakis sp. in North Sea herring (Clupea harengus) after capture was examined by a sensitive quantitative method (digestion). In one winter and one summer experiment, the mean numbers of worms in freshly caught herring were 0.06 and 0.09 (in double fillets), 0.19 and 0.24 (in double belly flaps), and 10.4 and 7.8 larvae (in viscera), respectively. In each experiment herrings were stored ungutted for up to 5 1/2 d on ice (0°C), in refrigerated/chilled sea water (-10°C), or in warm sea water (10°C), but no changes in the numbers of Anisakis larvae in the belly flaps and the fillets could be demonstrated. The present results show that Anisakis larvae are present in the flesh of herring already at capture, but no significant postmortem migration into the flesh could be demonstrated during storage. Thus, immediately gutting on board cannot eliminate or even reduce the risk from eating raw or inadequately processed herring.

In this paper, a fast and robust graph-based approach for boundary estimation of fiber bundles derived from Diffusion Tensor Imaging (DTI) is presented. DTI is a non-invasive imaging technique that allows the estimation of the location of white matter tracts based on measurements of water diffusion properties. Depending on DTI data, the fiber bundle boundary can be determined to gain information about eloquent structures, which is of major interest for neurosurgery. DTI in combination with tracking algorithms allows the estimation of position and course of fiber tracts in the human brain. The presented method uses these tracking results as the starting point for a graph-based approach. The overall method starts by computing the fiber bundle centerline between two user-defined regions of interests (ROIs). This centerline determines the planes that are used for creating a directed graph. Then, the mincut of the graph is calculated, creating an optimal boundary of the fiber bundle.

To study the time trend of PCDD, PCDF and dl-PCB levels in the muscle of herring from the Western Baltic Sea, samples were collected in 2006 at the same fishing locations as in 1999. The results demonstrated no obvious change in contamination levels based on content in fat during the last 7 years. The site-dependent increase in WHO-PCDD/F-PCB-TEQ concentrations already found in 1999 in fishing grounds between the Skagerrak and the east of Bornholm could be confirmed by this study. In addition, an overview is given in this study on the actual WHO-TEQ concentrations in cod, eel, herring, sprat and some salmon landed at various fishing ports along the coast of Mecklenburg-Western Pomerania/Germany. All herring samples were found to be below the maximum levels and the concentrations in cod were below 1 ng WHO-TEQ kg−1 wet weight (ww). The contaminant levels of 28 pooled eel samples varied considerably between 1.35 and 16.75 ng WHO-TEQ kg−1 ww. The results are discussed in relation to the fat content and to the weight of the eels.

This study was carried out in two research centres which are Centre 1 in Germany and Centre 2 in Ireland. In Centre 1, canning experiments were carried out by using blue whiting that had quality which was principal to be used as a raw material for canned products. However the quality was inferior when compared with commercial canned herring product in tomato sauce that is well accepted in German market. Centre 2 involved evaluation of the shelf life and sensory panel of blue whiting fillets. The blue whiting was sourced as block frozen fillets and individually quick frozen (IQF) fillets. They were tempered and evaluated as chilled fillets packed in modified atmosphere (MAP), or in air to assess their potential suitability for sale from chilled retail markets. Outcomes suggests that chilled Blue whiting fillets originating as block frozen or IQF samples have potential for sale in retail packs at 2-4°C, especially when packed in MA and when cooked by pan frying. These have a high quality shelf life of about 5 days at 2-4°C. Frozen breaded blue whiting goujons and nuggets were also well accepted. Further research was undertaken to observe some trace elements and cholesterol content in the muscle of blue whiting.

In 1995-1998 the contents of polychlorinated dibenzodioxins and dibenzofurans of 184 pooled fish samples were analysed. Sampling focused on fish and fishery products with a market share of more than 1% and covered all fishing grounds important for the supply of the German market. Investigation included 15 different fish species, shrimp, mussel and squid samples and various fishery products, typically on the German market. Generally lean fish species like cod, saithe or Alaska pollock were less contaminated on fresh weight basis than fat fish species like herring, Greenland halibut and sardine. In herring the dioxin content is related to the fishing ground. Low concentrations were found in North Sea herring, high concentrations measured in samples from the Baltic Sea. Dioxin contents in fishery products did not differ significantly from the raw fish samples. Results allow an estimation of the daily intake of dioxins and furans via fish consumption in Germany. Based on a daily fish consumption of 20 g the average intake of dioxins via fish is 6.2 pg WHO-PCDD/F-TEQs per person and day.

The levels of 13 polycyclic aromatic hydrocarbons (PAH) were determined by an HPLC method with fluorescence and UV detection and by a GC/MS technique in smoked fishery products from modern smoking kilns with external smoke generation and from traditional smoking kilns. The average benzo(a)pyrene (BaP) concentration of all 35 samples from commercial smoking kilns with external smoke generation was 0.1 microgram/kg (wet weight) and the sum of the carcinogenic compounds determined in the study, i.e. benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenz(a,h)anthracene and indeno(1,2,3-c,d)pyrene did not exceed 4.5 micrograms/kg (wet weight). The BaP levels of the 27 smoked fish samples from traditional kilns ranged from 0.2 microgram/kg to 4.1 micrograms/kg, with a mean value of 1.2 micrograms BaP/kg. The average concentration of the sum of the carcinogenic compounds was 9.0 micrograms/kg. Large variations were found in the content of the non-carcinogenic PAHs phenanthrene, anthracene, fluoranthene and pyrene in all samples from both types of smoking kilns.

For synthetic purposes mannobiose is isolated from the polysaccharide mannan of ivory nut flower. The chain length of mannan A is determined to approximately 15 mannose units on average with a definite distribution from 5 to 25 mannose units. Acetolysis is optimized and yields 41% mannobiose. The separation on Sephadex G-15 yields pure mannobiose, and in addition its higher homologues in gram amounts. Detection of the eluates is performed using a differential refractometer. Correspondingly laminaribiose can be obtained from the polysaccharides laminaran (brown algae Laminaria hyperborea) and pachyman (fungus Poria cocos Wolf, Bukuryo) by selectively optimized acetolysis in 30% yield. Depending on the starting material separations are favourably performed on silica gel or on Sephadex G-15. Laminaribiose and its higher homologues are obtained in gram amounts.

Rac. α-(Alkyl-, Aralkyl- und Arylacylamino)-propiophenone 1 werden von verschiedenen Kryptobasen stets zu entsprechenden (+) 2-Amino-1-phenylpropanolen-(1) 2 mit threo-Konfiguration reduziert. Die Reduktionsmittel Aluminiumisopropylat, auch im Gemisch mit Chloralu-minium-diisopropylat, oder Natriumborhydrid bewirken keinen Unterschied im sterischen Resultat.

High-performance liquid chromatography on silica gel was successfully applied to the separation of 15 monosaccharide peracetates. The solvent system acetone-n-hexane gave the most efficient separations at the optimal flow-rate. Dependences of retention times or capacity factors on flow-rate or pressure were determined for all derivaties. The chromatograms obtained showed clear separations of all derivatives, including epimers and anomers. Similarly, 12 disaccharide peracetates were analysed. The best solvent system was acetone-n-pentane, and again the resulting chromatograms showed excellent separations. For detection both a UV photometer and a refractive index detector can be used, depending on the eluent. Acid cleavage and subsequent peracetylation of the polysaccharide guaran gave a mixture of peracetylated monosaccharides. The interpretation of the chromatogram led to qualitative results and, after careful calibration, to quantitative results for the ratio of galactose to mannose residues in guaran.