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1.
Food Chem ; 302: 125331, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31404867

RESUMO

Adulteration of the high-value silver pomfret (Pampus argenteus) is a serious problem worldwide, necessitating accurate identification and quantification of the species. In this study, optimisation of the digital droplet PCR (ddPCR) assay for the identification and quantification of the silver pomfret was carried out. The primer and probe concentrations, melting temperature, and PCR cycle number were optimised by combining single-factor experiments with an orthogonal experimental design. The absolute limits of detection and quantification of the ddPCR were 2copies/µl and 21 copies/µl, respectively. Its sensitivity was 0.1% for meat mixtures and 0.5% for DNA mixtures. The ddPCR was 156 times more sensitive than the real-time PCR, although both methods had similar specificities. However, the overall time needed to complete the ddPCR method was twice that of the real-time PCR. Notwithstanding, the ddPCR methodology established in this study can be a valuable tool for addressing species adulteration issues.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Perciformes/genética , Reação em Cadeia da Polimerase/métodos , Animais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Nature ; 574(7776): 95-98, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31554969

RESUMO

Micronutrient deficiencies account for an estimated one million premature deaths annually, and for some nations can reduce gross domestic product1,2 by up to 11%, highlighting the need for food policies that focus on improving nutrition rather than simply increasing the volume of food produced3. People gain nutrients from a varied diet, although fish-which are a rich source of bioavailable micronutrients that are essential to human health4-are often overlooked. A lack of understanding of the nutrient composition of most fish5 and how nutrient yields vary among fisheries has hindered the policy shifts that are needed to effectively harness the potential of fisheries for food and nutrition security6. Here, using the concentration of 7 nutrients in more than 350 species of marine fish, we estimate how environmental and ecological traits predict nutrient content of marine finfish species. We use this predictive model to quantify the global spatial patterns of the concentrations of nutrients in marine fisheries and compare nutrient yields to the prevalence of micronutrient deficiencies in human populations. We find that species from tropical thermal regimes contain higher concentrations of calcium, iron and zinc; smaller species contain higher concentrations of calcium, iron and omega-3 fatty acids; and species from cold thermal regimes or those with a pelagic feeding pathway contain higher concentrations of omega-3 fatty acids. There is no relationship between nutrient concentrations and total fishery yield, highlighting that the nutrient quality of a fishery is determined by the species composition. For a number of countries in which nutrient intakes are inadequate, nutrients available in marine finfish catches exceed the dietary requirements for populations that live within 100 km of the coast, and a fraction of current landings could be particularly impactful for children under 5 years of age. Our analyses suggest that fish-based food strategies have the potential to substantially contribute to global food and nutrition security.


Assuntos
Pesqueiros , Peixes/metabolismo , Abastecimento de Alimentos , Internacionalidade , Micronutrientes/deficiência , Micronutrientes/metabolismo , Estado Nutricional , Animais , Teorema de Bayes , Cálcio/análise , Pré-Escolar , Proteínas na Dieta/análise , Ácidos Graxos Ômega-3/análise , Produtos Pesqueiros/análise , Produtos Pesqueiros/economia , Pesqueiros/economia , Peixes/classificação , Humanos , Lactente , Ferro/análise , Micronutrientes/análise , Selênio/análise , Vitamina A/análise , Zinco/análise
3.
J Sci Food Agric ; 99(14): 6462-6473, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31298738

RESUMO

BACKGROUND: Biochemical and protein conformational changes in silver carp occurred during ice storage, affecting the physico-chemical and textural properties of its washed mince. Fourier-transform infrared spectroscopy (FTIR) and FT Raman could offer insightful molecular-level information that could be related to the freshness of fish and textural properties of washed mince. RESULTS: The K value increased from 15.8% to 85.0% after 14 days on ice. The surface hydrophobicity of silver carp muscle proteins increased during ice storage, and its thrice-washed mince showed the same trend. The yield and textural properties of washed mince continually decreased as the storage time was extended. Fourier-transform infrared spectroscopy revealed that, as storage time increased, the α-helix content of mince decreased, while the ß sheet content increased. Prolonged ice storage led to the exposure of buried aromatic amino acid residues and an increase in disulfide interchanges in mince and washed mince. Changes in the ∑ß sheet structure and Raman intensity at 828 cm-1 observed in mince correlated well with the K value. The α-helix content and Raman intensity of raw washed mince at 621 and 828 cm-1 showed a strong correlation with its textural properties. CONCLUSION: Silver carp should be processed to surimi within 7 days of ice storage to obtain a reasonably good yield and gel texture. Infrared and Raman spectroscopy can possibly be utilized to monitor freshness quality and protein conformational changes in silver carp and to estimate the textural properties of washed mince as affected by freshness. © 2019 Society of Chemical Industry.


Assuntos
Produtos Pesqueiros/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Animais , Carpas , Proteínas de Peixes/química , Interações Hidrofóbicas e Hidrofílicas , Proteínas Musculares/química , Controle de Qualidade
4.
Food Chem ; 300: 125180, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325753

RESUMO

An isonicotinic acid hydrazide (INAH) chemically modified fumed silica, as a novel adsorbent, was designed for the preconcentration and determination of Hg (II) ions in fish samples via the solid phase extraction followed by the hydride generation atomic absorption spectrometry (HG-AAS). In this work, the efficiency of the synthesized adsorbent was investigated to determine its ability for the extraction of the Hg (II) ions from the aqueous solutions. The extraction efficiency was investigated by optimizing of different experimental conditions, such as pH, sample volume, flow rate, adsorbent dosage, and eluent type. Under the optimal conditions, a linear calibration curve for the solid phase extraction method was obtained in the range of between 0.12 and 16.5 µg L-1. The obtained detection limit and preconcentration factor were 0.018 µg L-1 and 25, respectively (RSD > 3%). The proposed optimized method was successfully applied to fish samples.


Assuntos
Produtos Pesqueiros/análise , Mercúrio/análise , Nanopartículas/química , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Adsorção , Animais , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Mercúrio/isolamento & purificação , Dióxido de Silício/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
5.
Artigo em Inglês | MEDLINE | ID: mdl-31361192

RESUMO

A liquid chromatography high resolution mass spectrometry (LC-HRMS) screening method was developed previously to analyze for veterinary drug residues commonly found in different types of aquaculture products. This method has been further evaluated for its feasibility to detect several other classes of compounds that might also be a concern as possible contaminants in farmed tilapia, salmon, eel and shrimp. Some chemicals could contaminate water sources used in aquaculture production through agricultural run-off. These compounds include several widely used triazine herbicides, organophosphate and carbamate pesticides, as well as various discarded human pharmaceuticals. Other possible contaminants investigated were selected disinfectants, some newer antibiotics, growth promoters, and various parasiticides. The sample preparation consisted of an acidic acetonitrile extraction followed by solid-phase extraction clean-up. Data were collected with a quadrupole-Orbitrap MS using both non-targeted and targeted acquisition. This rapid clean-up procedure and HRMS detection method described previously for veterinary drug residues also worked well for many other types of compounds. Most analytes had screening limit levels between 0.5-10 ng/g in the matrices examined using exact mass identification criteria. The strategy described in this paper for testing the performance of additional analytes will help expand the applicability of the HRMS procedure as aquaculture samples can now be analyzed for a wider range of contaminants.


Assuntos
Aquicultura , Resíduos de Drogas/análise , Produtos Pesqueiros/análise , Peixes , Análise de Alimentos , Contaminação de Alimentos/análise , Praguicidas/análise , Drogas Veterinárias/análise , Animais , Cromatografia Líquida , Humanos , Espectrometria de Massas
6.
J Food Sci ; 84(7): 1881-1887, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31264719

RESUMO

Nowadays, Listeria monocytogenes continues to be a major health issue. Therefore, improvements in the speed and reliability of its detection are still needed. In the present study, the combination of real-time Recombinase Polymerase Amplification (qRPA) with immunomagnetic separation (IMS) is described. The proposed methodology was tested against a real-time PCR method, and was successfully applied to 50 smoked salmon samples spiked at levels ranging from 2 to 9.3 × 102 cfu/25 g. L. monocytogenes was detected after a 24 hr pre-enrichment, which represents a great improvement over other previously published RPA methods. Additionally, the evaluation of the method reported a Limit of dDetection 50 (LoD50 ) of 6.3 cfu/25 g, along with relative sensitivity, specificity and accuracy values higher than 90%. Finally, the index of kappa concordance was calculated to be 0.93 which is interpreted as "almost complete concordance" between the reference and alternative method. Overall, the described methodology proved to be faster, specific, and as sensitive as other methods based on RPA or real-time PCR. PRACTICAL APPLICATION: The methodology described in this study significantly reduces the detection time of L. monocytogenes, when compared with culture-based methods, and it requires fewer steps than other molecular methods, making it a reliable and more convenient method for routine testing. Finally, the evaluation of the methodology in spiked food samples, confirms its reliability.


Assuntos
Produtos Pesqueiros/microbiologia , Separação Imunomagnética/métodos , Listeria monocytogenes/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Salmão/microbiologia , Animais , Produtos Pesqueiros/análise , Microbiologia de Alimentos , Listeria monocytogenes/genética , Reação em Cadeia da Polimerase em Tempo Real , Recombinases/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Food Chem ; 298: 125029, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260974

RESUMO

Thermal processing methods have important effects on food lipids. In this work, ultra-high-performance liquid chromatography-Q-Extractive Orbitrap mass spectrometry and lipidsearch software were applied to analyze effect of three types of thermal processing methods on the lipidomics profile of tilapia fillets. A total 15 classes of compound lipids (Cer, DG, LPC, LPE, LPG, LPI, LPS, PC, PE, PG, PI, PS, SM, So, TG) were analyzed. In addition, free DHA, EPA, and ARA were also identified. Furthermore, statistical analyses of these lipids were performed based on MetaboAnalyst software. The results demonstrated three types of thermal processing methods had different effects on lipidomics profile differences of tilapia fillets. A total of eight lipid species variables (LPS, LPG, LPI, DG, LPC, TG, LPE, and Cer) and 137 individual lipids variables showed significant differences among raw, steamed, boiled, and roasted tilapia fillets. This work could provide useful information for aquatic product processing and lipidomics.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Indústria de Processamento de Alimentos/métodos , Lipídeos/química , Tilápia , Animais , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/estatística & dados numéricos , Lipídeos/análise , Espectrometria de Massas/métodos
8.
Food Chem ; 298: 125087, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31272052

RESUMO

In this study, comprehensive analysis was performed to evaluate the impact of high hydrostatic pressure (HHP) and traditional thermal processing methods (baking and steaming) on cod proteins. Results showed that HHP, but not baking or steaming, was able to increase the content of soluble protein nitrogen (1.42-fold), compared with control. Total peptide contents of HHP-treated samples were also significantly higher than baked and steamed ones. In addition, protein oxidation was greatly increased after baking (1.56-fold) and steaming (1.97-fold), whereas HHP did not exhibit any appreciable effect. Furthermore, the allergenicity of cod was significantly reduced after HHP as reflected by the attenuated IgE and IgG-binding capacities (67-84% relative to control), while baking and steaming resulted in higher allergenicity. This study strongly supports the potential of HHP for reducing allergenicity, avoiding protein oxidation, and improving digestibility of cod and other protein-rich foods susceptible to quality deterioration during thermal processing.


Assuntos
Proteínas de Peixes da Dieta/química , Hipersensibilidade Alimentar/prevenção & controle , Indústria de Processamento de Alimentos/métodos , Gadus morhua , Animais , Culinária , Digestão , Produtos Pesqueiros/análise , Proteínas de Peixes da Dieta/farmacocinética , Hipersensibilidade Alimentar/imunologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Pressão Hidrostática , Imunoglobulina G/metabolismo , Nitrogênio/análise , Oxirredução , Carbonilação Proteica , Vapor , Compostos de Sulfidrila/análise , Compostos de Sulfidrila/química
9.
Food Chem ; 299: 125140, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299520

RESUMO

Pigment-depletion in the fillets of farmed Atlantic salmon (Salmo salar) arises after periods of elevated water temperatures with voluntary starving. This study tested the effects of dietary pre-loading with different pigment carotenoids (astaxanthin and/or canthaxanthin) combined with two α-tocopherol levels (normal and high: 500 and 1000 mg/kg, respectively) on pigment-depletion in vivo in Atlantic salmon after four weeks of challenge. We also tested whether oxidative stress manifested as an underlying depletion mechanism. Carotenoid levels in whole fillet homogenates were not decreased significantly post-challenge but fillet α-tocopherol concentrations were increased significantly in contrast to decreased oxidative stress indices. However, image analysis revealed localised fillet pigment-depletion following all dietary treatments. These data imply that localised pigment-depletion was not prevented by pre-loading of the fillet with different carotenoid-types/mixtures and increased of α-tocopherol levels from normal to high, respectively. Further, we suggest that oxidative stress might not facilitate pigment-depletion in vivo.


Assuntos
Cantaxantina/metabolismo , Pigmentos Biológicos/metabolismo , Salmo salar/fisiologia , alfa-Tocoferol/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura/métodos , Cantaxantina/análise , Dieta , Feminino , Produtos Pesqueiros/análise , Estresse Oxidativo , Pigmentação , Inanição , Temperatura Ambiente , Xantofilas/análise , Xantofilas/metabolismo
10.
Mar Pollut Bull ; 142: 510-519, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232331

RESUMO

This study aims at quantifying and characterising microplastics (MP) distribution in the water column of the NW Mediterranean Sea as well as MP ingestion by the 2 main planktivorous fish of the area, sardine and anchovy. Debris of similar sizes were found in all water column samples and in all but 2 fish guts (out of 169). MP were found in 93% of water column samples with an average concentration of 0.23 ±â€¯0.20 MP·m-3, but in only 12% of sardines (0.20 ±â€¯0.69 MP·ind-1) and 11% of anchovies (0.11 ±â€¯0.31 MP·ind-1). Fibres were the only shape of MP encountered and polyethylene terephthalate was the main polymer identified in water columns (61%), sardines (71%) and anchovies (89%). This study confirms the ubiquity of MP in the Mediterranean Sea and imparts low occurrence in fish digestive tracts.


Assuntos
Peixes , Conteúdo Gastrointestinal/química , Plásticos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Poluentes Químicos da Água/análise , Animais , Exposição Dietética , Ecotoxicologia/métodos , Produtos Pesqueiros/análise , Mar Mediterrâneo , Água do Mar/análise
11.
Artigo em Inglês | MEDLINE | ID: mdl-31161892

RESUMO

Insects are promising sources of protein and lipid in feeds for farmed animals. In the European Union, the use of insect meal (IM) and insect oil is permitted in fish feed. However, the European Food Safety Authority has highlighted the lack of data regarding the chemical safety of insects and products thereof. In this study, Atlantic salmon (Salmo salar) were fed diets in which fish meal (FM) was partially or fully substituted with IM, resulting in four diets with an FM replacement of 0%, 33%, 66% and 100% by IM. The IM was produced from Black soldier fly (Hermetia illucens) larvae fed media containing 60% seaweed (Ascophyllum nodosum). After 16 weeks of feeding, fish fillet samples were collected. The concentrations of undesirable substances, e.g., heavy metals, arsenic, dioxins, mycotoxins, pesticides, in the IM, the diets and fillets were determined. The concentrations of the analysed compounds in the IM were all below EU maximum levels for feed ingredients, except for arsenic. However, for complete feeds the concentrations of these compounds in the feeds, including arsenic, were all below EU MLs. Arsenic was transferred from seaweed to IM, resulting in arsenic levels in IM similar to what has been documented for FM. Transfer of arsenic from feed to fillet was observed; however, total arsenic concentrations in the fillet significantly decreased when fish were fed diets with more IM and less FM. Arsenic speciation analysis of the diets showed that although total arsenic levels were similar, the arsenic species were different. Arsenobetaine was the major organoarsenic species in the diets containing FM, while in diets containing IM several unidentified arsenic species were detected. The results suggest that the lower feed-to-fillet transfer of arsenic when FM is replaced by IM may be due to the presence of arsenic species with low bioavailability in the IM.


Assuntos
Ração Animal/análise , Arsênico/análise , Dieta/veterinária , Produtos Pesqueiros/análise , Contaminação de Alimentos/análise , Insetos/química , Salmo salar/metabolismo , Animais , Análise de Alimentos , Inocuidade dos Alimentos
12.
J Food Sci ; 84(7): 1871-1880, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218691

RESUMO

Impact of dielectric barrier discharge high-voltage cold atmospheric plasma (DBD-HVCAP) generated with the mixture of oxygen and argon (10:90) for various treatment times (2.5 to 10 min) on the qualities of Asian sea bass slices during 4 °C storage was investigated. Microbial load of slices treated with DBD-HVCAP were lower than the control. The efficacy of bacteria reduction by DBD-HVCAP was dependent on the treatment times (P < 0.05). Total viable bacteria count (TVBC) was more than 6.0 Log CFU/g at day 6 for the control kept in air. Slices treated with DBD-HVCAP for all treatment times used had TVBC lower than the limit at day 12. Total volatile nitrogen base content (TVNB) as well as trimethylamine (TMA) content in slices treated with DBD-HVCAP were lower than that of the control throughout the storage. TVNB as well as TMA contents were lower in HVCAP treated slices in a treatment time-dependent manner. Nevertheless, lipid oxidation in samples treated with DBD-HVCAP was higher than that of the control. Polyunsaturated fatty acids were decreased in slices treated with DBD-HVCAP for more than 5 min after 12 days of storage. Therefore DBD-HVCAP treatment for 5 min was demonstrated to be potential means for increasing the shelf-life of Asian sea bass slices with minimal negative effect on chemical and sensory properties, in which they could be stored longer than 12 days at 4 °C. PRACTICAL APPLICATION: Microbial inactivation capacity of dielectric barrier discharge high-voltage cold atmospheric plasma (DBD-HVCAP) has been documented with limited information on its application in extending the shelf-life of foods. DBD-HVCAP was demonstrated as an innovative technology for extending the shelf-life of Asian sea bass slices, which could be implemented in seafood industries for assuring safety and extending shelf-life of products. The shelf-life of the slices treated with DBD-HVCAP was extended to 12 days of storage at 4 °C as compared to the 6 days of the untreated counterpart.


Assuntos
Bass/microbiologia , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Gases em Plasma/farmacologia , Animais , Argônio/química , Argônio/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Produtos Pesqueiros/microbiologia , Armazenamento de Alimentos , Oxigênio/química
13.
Arch Environ Contam Toxicol ; 77(2): 263-278, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31127395

RESUMO

We investigated the distribution of Zn, Cu, Ni, Pb, Cr, and Cd in water, sediment, and two dietary fish (an omnivore, Labeo rohita and a benthic carnivore, Clarias batrachus) and potential health risk to human consumers during summer low flow (2017-2018) at 28 sites across 7 tributary confluences of the Ganga River. We selected Devprayag, an upper reach site, as a reference for data comparison. We found significant spatial variations in the distribution of study metals and the concentrations remained higher in tributaries, confluences, and downstream cities. The pollution load index showed all sites except Devprayag in the polluted category. Ecological risk analysis indicated 1 site with very high risk, 7 with considerable risk, and 10 with moderate-risk category. The Zn did appear the most, and Cd the least accumulated metal in the fish. The metal accumulation was higher in C. batrachus. The levels of Cd, Cr, and Pb in the study fishes were higher compared with the international standards. The health risk analysis indicated safe levels for individual metals except for Cd where the target hazard quotient (THQ) did exceed 1 for C. batrachus at the Ramganga and Varuna confluences. When all metals were considered, the THQ was > 1 (> 2 for C. batrachus), indicating the full possibility of adverse health effects to human consumers. Our study highlights the importance of tributaries in creating a mosaic of metal-rich habitats in the Ganga River and food chain associated with a health risk to human consumers.


Assuntos
Peixes-Gato , Cyprinidae , Metais/análise , Medição de Risco/métodos , Poluentes Químicos da Água/análise , Adulto , Animais , Criança , Exposição Dietética/efeitos adversos , Produtos Pesqueiros/análise , Cadeia Alimentar , Contaminação de Alimentos/análise , Humanos , Nível de Efeito Adverso não Observado , Rios/química , Estações do Ano
14.
J Sci Food Agric ; 99(12): 5417-5423, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31077387

RESUMO

BACKGROUND: Smoked fish is a major source of animal protein in developing countries. It is largely produced by hot-smoking on traditional kilns using fuelwood. This practice is associated with high polycyclic aromatic hydrocarbon (PAH) contamination in products, with consequences for public health. An improved kiln, comprising the FAO-Thiaroye Technique (FTT), has been introduced by the Food and Agriculture Organization of the United Nations to address such a concern. The present study investigated the efficacy of the FTT in Ghana through comparative fish smoking experiments with traditional kilns followed by determination of PAH levels [benzo(a)pyrene (BaP) and PAH4] in the products by gas chromatography-mass spectrometry. For each kiln, the effect of smoking fuel type on PAH contamination was determined. The impact of the design characteristics of the FTT on the levels of the compounds was also determined. RESULTS: Mean BaP and PAH4 levels in the FTT products were up to 1.8 and 7.6 µg kg-1 , respectively, whereas the corresponding levels in traditional kiln products were up to 70 and 395 µg kg-1 . PAH levels in FTT products were below European Union regulatory limits, whereas levels in traditional kiln products exceed such limits by up to 33-fold. Across kiln types, the use of wood fuels caused higher PAH contamination compared to the use of fully-lit charcoal as an alternative fuel. CONCLUSION: The improved kiln (FTT) is efficacious in yielding smoked fish with a PAH content lower than the levels in traditional kiln products and also below current regulatory limits. Kiln design and type of processing fuel have significant impacts on PAH contamination during fish smoking. © 2019 Society of Chemical Industry.


Assuntos
Produtos Pesqueiros/análise , Contaminação de Alimentos/análise , Conservação de Alimentos/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Benzo(a)pireno/análise , Carvão Vegetal/efeitos adversos , Carvão Vegetal/análise , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/instrumentação , Cromatografia Gasosa-Espectrometria de Massas , Gana , Madeira/efeitos adversos , Madeira/química
15.
J Food Sci ; 84(6): 1288-1296, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31120570

RESUMO

The preservation effects of tartary buckwheat extract (T) and chitosan (C) coatings on the physicochemical (pH value, thiobarbituric acid value, Peroxide value (PV), total volatile basic nitrogen (TVB-N), K value, surface color and the texture profiles), bacteriological (total viable counts (TVC) and psychrotrophic bacteria counts (PBC)), and sensory characteristics of tilapia (Oreochromis niloticus) fillets storage at 0 °C for 18 days were evaluated. The fillets coated with 0.5% T + 1.0% C, 1.0% T + 1.0% C and 1.5% T + 1.0% C maintained better quality and had longer shelf life with respect to samples coated with chitosan alone and the control. Base on the limit values of TVB-N, K value, TVC and sensory preference scores, the shelf life of control fillets was 6 days. By contrast, shelf life of 9 days for 0.5% T + 1.0% C-coated fillets, 12 days for 1.0% T + 1.0% C treated-fillets, and 15 days for 1.5% T + 1.0% C-treated fillets were obtained. Therefore, TBE combined with chitosan coatings have the potential to extend the shelf life of tilapia fillets during storage at 0 °C. PRACTICAL APPLICATION: This study provides basic theory regarding the application of TBE to fish preservation. The edible coating of TBE combined with chitosan has potential use in developing activity food preservation coating.


Assuntos
Quitosana/química , Fagopyrum/química , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Extratos Vegetais/química , Animais , Ciclídeos , Cor , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Humanos , Paladar
16.
J Agric Food Chem ; 67(23): 6650-6657, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31094514

RESUMO

The use of the synthetic antioxidant ethoxyquin (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline, EQ) as a flame retardant in fish meal transported by sea is required by international authorities to prevent self-ignition. Because of extensive carry-over within the food chain, selective and sensitive analytical methods are required for investigations on human exposure and the safety of EQ and its metabolites. Therefore, a simple, fast, and rugged liquid-chromatography (LC) method was developed for the detection of EQ and its metabolites in fish and fishery products after liquid-liquid extraction using QuEChERS. For screening purposes, a fluorescence detector was used (LC-FLD) with the EQ-analogue methoxyquin serving as an internal standard. For stable-isotope dilution analysis by liquid chromatography-tandem mass spectrometry (SIDA-LC-MS/MS), deuterated analogues of EQ and its metabolites were synthesized for the first time and allowed for sensitive quantification and thus confirmation of screening results. Both methods were validated and successfully applied to commercially available fish samples.


Assuntos
Antioxidantes/química , Cromatografia Líquida/métodos , Etoxiquina/química , Produtos Pesqueiros/análise , Peixes/metabolismo , Técnicas de Diluição do Indicador , Espectrometria de Massas em Tandem/métodos , Animais , Antioxidantes/metabolismo , Etoxiquina/metabolismo , Fluorescência , Alimentos Marinhos/análise
17.
Mar Pollut Bull ; 141: 521-528, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955764

RESUMO

This is the first study on polychlorinated biphenyls (PCBs) in fish from the Cau Hai lagoon, a part of the largest coastal lagoon in Southeast Asia. Seven selected PCB congeners and organochlorine pesticides in sediments and edible fish tissues were quantified by GC-MS. The sum of ICES-7 PCB and DDTs concentrations in fish species consumed regularly and of economic value were in ranges 26-43 ng g-1 lw and 182-277 ng g-1 lw, respectively. The ratio between the parent DDT compound and the sum of metabolites, DDE and DDD, was most of the time smaller than 1, suggesting primarily an historical contamination of the lagoon. An agglomerative hierarchical clustering indicates sites located in the north-western part of the Cau Hai lagoon were characterized by above-average concentrations of DDE and DDT. Comparing to previous data, a large decrease in ∑DDT residues can be seen over the past 20 years.


Assuntos
Peixes , Sedimentos Geológicos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Animais , Aquicultura , DDT/análise , DDT/metabolismo , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Monitoramento Ambiental , Produtos Pesqueiros/análise , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/química , Humanos , Medição de Risco , Vietnã
19.
J Sci Food Agric ; 99(10): 4731-4738, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30924936

RESUMO

BACKGROUND: Sakacin-A due to its specific antimicrobial activity may represent a good candidate to develop active packaging solutions for food items supporting Listeria growth. In the present study a protein extract containing the bacteriocin sakacin-A, produced by Lactobacillus sakei Lb 706 in a low-cost culture medium containing deproteinized cheese whey, was adsorbed onto cellulose nanofibers (CNFs) to obtain an active material to be used as a mat (or a separator) in direct contact with foods. RESULTS: The applied fermentation conditions allowed 4.51 g L-1 of freeze-dried protein extract to be obtained, characterized by an antimicrobial activity of near 16 700 AU g-1 , that was used for the preparation of the active material by casting. The active material was then characterized by infrared spectra and thermogravimetric analyses. Antimicrobial trials were carried out in vitro using Listeria innocua as indicator strain; results were also confirmed in vivo, employing smoked salmon fillets intentionally inoculated with Listeria innocua: its final population was reduced to about 2.5-3 Log cycles after 28 days of storage at 6 °C in presence of sakacin-A, compared with negative control mats produced without the bacteriocin extract. CONCLUSION: This study demonstrates the possibility of producing an antimicrobial active material containing sakacin-A absorbed onto CNFs to decrease Listeria population in smoked salmon, a ready-to eat-food product. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antibacterianos/química , Bacteriocinas/química , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Nanofibras/química , Animais , Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Celulose/química , Fast Foods/análise , Fast Foods/microbiologia , Produtos Pesqueiros/microbiologia , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/farmacologia , Listeria/crescimento & desenvolvimento , Salmão/microbiologia
20.
Food Chem ; 287: 85-92, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30857722

RESUMO

Effects of two typical comminution methods (shearing and blending) on structural and biochemical properties of silver carp surimi were comparatively investigated. Surimi myofibrils in striated appearance were progressively disrupted within 15 min of blending. The myofibrils were completely disintegrated after shearing for 5 min. Surface hydrophobicity of surimi increased and then gradually decreased (p < 0.05) under shearing, while it continuously increased (p < 0.05) under blending. As shearing time was extended, α-helical structure decreased and ß-sheet structure increased simultaneously; surface active sulfhydryl content (SH) increased and then decreased (p < 0.05); and intensity of myosin heavy chain (MHC) was gradually reduced. However, secondary structure, MHC intensity and SH were slightly changed as blending time extended. Ca2+-ATPase activities increased and then declined (p < 0.05) with transition times at 1 min and 5 min under shearing and blending, respectively. Results indicated that shearing disrupted the ultrastructure and changed biochemical properties of surimi more pronouncedly than blending.


Assuntos
Carpas , Produtos Pesqueiros/análise , Animais , Interações Hidrofóbicas e Hidrofílicas , Miofibrilas/química , Cadeias Pesadas de Miosina/química , Estrutura Secundária de Proteína
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