Freshness indicators of defrosted fillets of Lepidocybium flavobrunneum in vacuum skin packaging/VSP packaging during cold storage

The aim of study was to monitor chemical parameters (pH, total volatile basic nitrogen, trimethylamine, free fatty acids, peroxide value, and thiobarbituric acid assay) in the samples of defrosted fillets of escolar (Lepidocybium flavobrunneum) fish, packed in vacuum skin packaging (VSP) during 15 days of storage at +2±2 °C. Comparison was done with fillets packed in vacuum (control samples). The obtained results from our research showed that VSP packaging can be recommended, as it showed slightly better stability than vacuum packaging. The initial values of total volatile basic nitrogen (TVBN) content (in mg/100 g) in fish samples were low (vacuum 16.36±0.65; VSP 16.67±0.45) and these values did not change significantly until day 9. TVBN was significantly higher (P2 kg−1 (vacuum 1.77±1.38; VSP2.16±0.11) and thiobarbituric acid assay content expressed in mg kg−1 (vacuum 4.20±0.43; VSP 4.10±2.61) were relatively low

Physical and Chemical Changes in Fresh Chilled Muscle Tissue of Common Carp (Cyprinus carpio L.) Packed in a Modified Atmosphere

The aim of the study was to monitor the course of physical and chemical changes taking place in stored fresh chilled muscle tissue of carp packed in modified atmosphere (MAP), and to determine its shelf life. Samples of muscle tissue of common carp (Cyprinus carpio, L.) were packed in MAP (80% O2, 20% CO2) and stored for 15 days at +2 ± 2 °C max. During the storage period, O2 level in packs decreased from 78.7 ± 0.39% (day 1) to 63.8 ± 1.30% (day 15). Decrease in O2 in packs between storage days 7 and 9 was highly significant (p -1 (day 15). Hydrolytic lipid decomposition (FFA) was more intensive in carp muscle tissue (2.09 ± 1.07% total lipid as oleic acid) than in carp skin (1.01 ± 0.31% total lipid as oleic acid) (day 15). Lipid oxidation (PV) in skin showed differences from lipid oxidation in muscle tissue. Oxidation processes in muscle correlated positively with the length of storage (r = 0.90). Over the storage period, peroxide levels increased from 2.58 ± 1.19 mekv O2 kg-1 (day 1) to 6.76 ± 1.78 mekv O2 kg-1 (day 15). Because of low TVBN levels in muscle tissue, shelf life was limited mainly by sensory changes (green discoloration, odour deviations, slime production), which were observed from storage day 9 onwards. It was found that the maximum shelf life of carp packed in MAP (80% O2, 20% CO2) was 7 days. The optimum parameter to determine the remaining shelf life of common carp muscle tissue stored at +2 ± 2 °C max is the TVBN level. As concerns shelf life, TVBN levels in carp muscle should not exceed 15 mg 100 g-1. This level of TVBN (max. 15 mg 100 g-1) for carp (MAP 80% O2, 20% CO2) is much more lower in comparison with levels TVBN (max 25 - 35 mg 100 g-1) which have been determined by Commission Regulation (EC) No. 2074/2005 for sea fish. For that reason we suggest to amplify the study by other monitoring (higher number of samples, various breeds of carp in different weight categories for all the year). On the basis of these analyses the level of TVBN for carp could be determined and incorporated to the legislation

Variability of selected physicochemical characteristics of defrosted whiteleg shrimps (Litopenaeus vannamei) after culinary processing

The aim of the study was to estimate how selected physical and chemical characteristics of defrosted modified atmosphere packaged (MAP) not deveined shrimp (green shrimp with head) (Litopenaeus vannamei) meat are affected by two of the most often used culinary processing (cooking and frying). The experiment was carried out with 61 green shrimps with head (the country of origin: Ecuador; MAP 30% CO2/70% N2; stored 8 days at 0 °C to +2 °C) samples and evaluation of weight loss, pH, total volatile basic nitrogen (TVBN), and trimethylamine (TMA) contents. Weight losses and pH of examined shrimp samples after cooking and frying were significantly (P<0.05) lower, while same fluctuations in TVBN and TMA contents were noticed between culinary treatments (cooking, frying) as between different parts of shrimp tails. Significant correlations (P<0.05) were found between pH values and freshness indicators (TVBN, TMA-N), emphasizing different ongoing post-mortem metabolic and degradation processes in different parts of edible shrimp (Litopenaeus vannamei) parts (peeled tail)

Factors influencing sushi meal as representative of non-traditional meal: Consumption among Czech consumers

Determination of consumers’ acceptance level of sushi meal among Czech respondents was the main aim. The survey included 1352 respondents that filled in a questionnaire on their demographic characteristics and food preferences regarding their acceptance of sushi meal. Additionally, 79 volunteers participated in sorting sushi among other 14 popular meals in the Czech Republic, according to their assumed situations. The results indicate that sushi is highly accepted among Czech consumers (more than 80% of respondents consume sushi) due to sensory characteristics and health benefit claims of sushi. The main barrier for sushi acceptance is sushi being a cold meal. The study emphasized that sushi price highly influences not only consumption frequency but also acceptance of sushi among respondents who declared not consuming this type of meal

Note on the special fillet fatty acid composition of the dwarf carp (Cyprinus carpio carpio) living in thermal Lake Hévíz, Hungary

Fatty acid (FA) composition of the fillet and the intestinal content of dwarf common carp (Cyprinus carpio carpio) living in Lake Hévíz was determined in wintertime collected samples and results were compared to widespread literature data on carp. Fillet FA profile of the thermally adapted (28 oC) Hévíz dwarf carps differed from profiles originated from divergent culture and feeding conditions in the overall level of saturation. Fillet myristic acid proportions largely exceeded all literature data in spite of poor dietary supply. Fillet fatty acid results indicate the effects of thermal adaptation (high saturation level) and the correlative effects of feed components rich in omega-3 fatty acids, with special respect to docosahexaenoic acid. With the application of discriminant factor analysis the Hévíz sample was accurately differentiated from the literature data on carp fillet fatty acid profile, mostly based on C14:0, C18:1 n9, C18:2 n6, C20:1 n9 and C20:4 n6 FAs. In summary, fillet FA profile suggested thermal adaptation, location specificity and the ingestion of algal and bacterial material