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Fresh Fish (fresh + fish)
Selected AbstractsSalted and fermented fish processes evaluationINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2009Cecília Riscado Pombo Summary Fish curing by salting and fermentation is the result of the action of certain enzymes over fresh fish. This study aimed to evaluate and compare three technological processing methods (A, B, C). Coliforms, Escherichia coli, Enterococcus spp., coagulase-positive Staphylococcus, Salmonella spp., total volatile base (TVB), pH, water activity (Wa), sodium chloride and biogenic amines were evaluated. A significant difference in histamine production (P < 0.05) was observed. Escherichia spp., Klebsiella spp, Proteus spp., Shigella spp., Citrobacter spp. and Pseudomonas spp. were isolated. Sodium chloride content varied between 15.65 and 18.87% and no significant difference was observed (P > 0.05). Wa and pH showed significant differences (P < 0.05), with values between 0.71 and 0.75, and 5.54 and 5.93. TVB values varied between 15.1 and 62.1 mg N 100 g,1, showing significant differences (P < 0.05) as well. Worrying levels of histamine were found. Processing method A was found to be the most appropriate for the production of this kind of fish. [source] Characterisation of the volatiles of yellowfin tuna (Thunnus albacares) during storage by solid phase microextraction and GC,MS and their relationship to fish quality parametersINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 10 2007Ranjith K.B. Edirisinghe Summary Investigations were carried out to extract the volatile compounds of fish using solid phase microextraction (SPME) in order to develop a new rapid indicator for determining the quality of fish. Changes in the aroma composition of yellowfin tuna (Thunnus albacares) was studied at 30 °C and in ice, using SPME GC,MS, and their relationship with the fish quality parameters , total volatile basic nitrogen and sensory analysis , was determined using principal component analysis (PCA) and stepwise multiple regression analysis. Hexanal (30.9%) and 2-nonanone (28.4%) were recorded in relatively high amounts in fresh fish, whereas 3-methyl-1-butanol and 3-hydroxy-2-butanone increased with storage time. PCA clearly differentiated the volatile profile of each sampling stage (P < 0.05) throughout storage treatments. Regression analysis showed a significant relationship between the fish quality and the levels of 3-methyl-1-butanol and pentadecane. The findings highlight the possibility of developing a rapid quality evaluation method for fish using SPME GC,MS. [source] INFLUENCE OF FROZEN PERIOD ON THE PROXIMATE COMPOSITION AND MICROBIOLOGICAL QUALITY OF NILE TILAPIA FISH (OREOCHROMIS NILOTICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2010SHIMELIS A. EMIRE ABSTRACT The rationale of the study was to investigate the influence of frozen period on quality of fish fillet. The proximate composition and microbiological analyses were carried out at 15 days interval on tilapia fish fillets during frozen storage. It was found that the protein, moisture and ash contents decreased significantly (P < 0.05) during the entire storage period. However, the fat content increased from 0.37 ± 0.01 to 0.56 ± 0.01 g/100 g of fillet. The total volatile bases nitrogen and pH values also increased significantly The total bacterial load in fresh fillets was reduced from 2.57 × 106 to 8.2 × 105 cfu/g after 90 days of frozen storage. The total coliforms decreased from 460 to 23 MPN/g and the fecal coliforms decreased from 23 MPN/g to undetectable level, respectively. Thus, a significant quality loss was observed for tilapia during storage. However, the present frozen conditions retained the fish material under acceptable microbiological conditions for human consumption. PRACTICAL APPLICATIONS The main challenge that fish industries face in developing countries like Ethiopia is to comply with consumer expectations, particularly on product quality. The quality of fresh fish is one of the key factors that govern the shelf life of the final product at low temperature preservation. The Ethiopian fish production and marketing enterprise is vested with the responsibility of inland fisheries processing and marketing. The enterprise, without any scientific basis, labeled the frozen tilapia fish shelf life to be 9 months. Therefore, the aim of this study was to investigate the low-temperature (,18C) preservation technique practiced by the enterprise in order to evaluate the influence of frozen period on quality of a fish fillet. The results on changes in proximate composition and microbial load of Nile tilapia fish fillet enabled to determine the frozen period of a fish fillet that can be fit for human consumption devoid of deterioration. The results can also be used for further investigation and detailed research is required to help commercial processors beyond 90 days of frozen storage. [source] Occurrence of Histamine-Forming Bacteria in Albacore and Histamine Accumulation in Muscle at Ambient TemperatureJOURNAL OF FOOD SCIENCE, Issue 4 2002S.H. Kim ABSTRACT Distribution of histamine-producing bacteria in fresh albacore and their proliferation in muscle during storage at 25 °C were monitored. Histamine formers constituted a minor portion of the bacterial flora in albacore. Only weak histamine formers were detected in the gill and skin of fresh fish after enrichment. Histamine formers were isolated from the muscles when APC reached >107 CFU/g during storage. Hafnia alvei was most prevalent in both fresh and temperature-abused fish. The most prolific histamine former, Morganella morganii, was rarely isolated even from spoiled muscles. The prevalence of weak histamine formers resulted in low levels of histamine accumulation in muscle, 67.1 mg/100 g, for 6 d of storage. [source] Detection of Shiga-toxigenic Escherichia coli (STEC) in fresh seafood and meat marketed in Mangalore, India by PCRLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2001H. Sanath Kumar Aims: To study the incidence of Shiga-toxigenic Escherichia coli (STEC) in seafoods from India. Methods and Results:Escherichia coli isolated from various seafoods such as fresh fish, clams and water were screened for the presence of stx, hlyA and rfbO157 genes by PCR; 5% of clams and 3% of fresh fish samples were positive for non-O157 STEC. Conclusions: STEC is prevalent in seafoods in India, and non-O157 serotype is more common. Significance and Impact of the Study: Seafood could be a vehicle for transmission of STEC even in tropical countries. [source] Occupational allergy and asthma among salt water fish processing workersAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 12 2008Mohamed F. Jeebhay MBChB Abstract Background Fish processing is a common economic activity in Southern Africa. The aim of this study was to determine the prevalence and host determinants of allergic symptoms, allergic sensitization, bronchial hyper-responsiveness and asthma among workers processing saltwater fish. Methods A cross-sectional study was conducted on 594 currently employed workers in two processing plants involved in pilchard canning and fishmeal processing. A modified European Community Respiratory Health Survey (ECRHS) questionnaire was used. Skin prick tests (SPT) used extracts of common airborne allergens, fresh fish (pilchard, anchovy, maasbanker, mackerel, red eye) and fishmeal. Spirometry and methacholine challenge tests (MCTs; tidal breathing method) used ATS guidelines. Results Work-related ocular-nasal symptoms (26%) were more common than asthma symptoms (16%). The prevalence of atopy was 36%, while 7% were sensitized to fish species and 26% had NSBH (PC20,,,8 mg/ml or ,12% increase in FEV1 post-bronchodilator). The prevalence of probable occupational asthma was 1.8% and fish allergic rhino-conjunctivitis 2.6%. Women were more likely to report work-related asthma symptoms (OR,=,1.94) and have NSBH (OR,=,3.09), while men were more likely to be sensitized to fish (OR,=,2.06) and have airway obstruction (OR,=,4.17). Atopy (OR,=,3.16) and current smoking (OR,=,2.37), but not habitual seafood consumption were associated with sensitization to fish. Conclusions Based on comparison with previous published studies, the prevalence of occupational asthma to salt water fish is lower than due to shellfish. The gendered distribution of work and exposures in fish processing operations together with atopy and cigarette smoking are important determinants of occupational allergy and asthma. Am. J. Ind. Med. 51:899,910, 2008. © 2008 Wiley-Liss, Inc. [source] Changes in trimethylamine oxide and trimethylamine in muscle of wild and farmed cod (Gadus morhua) during iced storageAQUACULTURE RESEARCH, Issue 1 2009Hilde Herland Abstract Trimethylamine oxide (TMAO) is found at high levels in wild Atlantic cod. Trimethylamine oxide is reduced to trimethylamine (TMA) during iced storage. In this study, the levels of TMAO and TMA in wild and farmed cod and the impact of storage, gender and season on these levels were investigated. Wild cod had higher levels of TMAO than farmed cod. Wild cod also had higher levels of TMA after 15 days of iced storage. Farmed cod were found to have levels of TMA-N <5 mg/100 g after 15 days of iced storage, which is below the maximum permitted level for fresh fish. Therefore, TMA appears to be an unsuitable measure of freshness in farmed cod. Female farmed cod had higher levels of TMAO than male farmed cod; no such difference between genders was found in wild cod. Female and male farmed cod had similar levels of TMA after post-mortem iced storage. The hepatosomatic index (HSI) of female farmed cod was higher than that seen in male cod and this may be the underlying reason for the differences in muscle TMAO. Levels of TMAO in male farmed cod were higher during the autumn and were correlated with a larger HSI during the same period. [source] | ||||||||||