ABSTRACT
Wireless communication technologies, particularly radio frequency (RF), have been widely explored for wearable electronics with secure and user-friendly information transmission. By exploiting the operational principle of chemically actuated resonant devices (CARDs) and the electrical response observed in chemiresistive materials, we propose a simple and hands-on alternative to design and manufacture RF tags that function as CARDs for wireless sensing of meat freshness. Specifically, the RF antennas were meticulously designed and fabricated by lithography onto a flexible substrate with conductive tape, and the RF signal was characterized in terms of amplitude and peak resonant frequency. Subsequently, a single-walled carbon nanotube (SWCNT)/MoS2/In2O3 chemiresistive composite was incorporated into the RF tag to convey it as CARDs. The RF signal was then utilized to establish a correlation between the sensor's electrical response and the RF attenuation signal (reflection coefficient) in the presence of volatile amines and seafood (shrimp) samples. The freshness of the seafood samples was systematically assessed throughout the storage time by utilizing the CARDs, thereby underscoring their effective potential for monitoring food quality. Specifically, the developed wireless tags provide cumulative amine exposure data within the food package, demonstrating a gradual decrease in radio frequency signals. This study illustrates the versatility of RF tags integrated with chemiresistors as a promising pathway toward scalable, affordable, and portable wireless chemical sensors.
Subject(s)
Food Quality , Meat , Meat/analysis , AminesABSTRACT
This work aims to develop intelligent labels based on cassava starch and biohybrid pigments by thermo-compression. The biohybrid pigment (BH) was developed by the adsorption of anthocyanins (ACNs) extracted from the jambolan fruit (Syzygium cumini L.) into montmorillonite (Mt) in order to improve its stability. The effect of the addition of biohybrid on the physicochemical properties of the thermo-pressed starch labels was evaluated. ACNs from jambolan extract show a visible pH-dependent color-changing ability at pH 1 - 12, and the adsorption did not modify the color property. The intelligent labels presented a homogeneous surface, and the BH was well dispersed in the starch matrix. The presence of BH increased the solubility in the water of starch labels. Chemical structure characterization revealed that the BH interacted with starch matrices through hydrogen bonds. Furthermore, the thermal stability of starch labels increased with the presence of BH. Hence, the purple color of intelligent labels was preserved at high temperatures. Finally, labels containing BH show visible changes from purple to a blue color when exposed to ammonia vapor, which simulates the degradation of meat products. Thus, the label content jambolan pigments will be used to control meat deterioration.
Subject(s)
Anthocyanins , Syzygium , Ammonia , Anthocyanins/chemistry , Bentonite , Food Packaging , Hydrogen-Ion Concentration , Plant Extracts/chemistry , Starch/chemistry , Syzygium/chemistry , WaterABSTRACT
Fish is a high nutritional value matrix of which production and consumption have been increasing in the last years. Advancements in the efficient evaluation of freshness are essential to optimize the quality assessment, to improve consumer safety, and to reduce raw material losses. Therefore, it is necessary to use rapid, nondestructive, and objective methodologies to evaluate the quality of this matrix. Quality Index Method (QIM) is a tool applied to indicate fish freshness through a sensory evaluation performed by a group of assessors. However, the use of QIM as an official method for quality assessment is limited by the protocol, sampling size, specificities of the species, storage conditions, and assessor's experience, which make this method subjective. Also, QIM may present divergences regarding the development of microorganisms and chemical analysis. In this way, novel quality evaluation methods such as electronic noses, electronic tongues, machine vision system, and colorimetric sensors have been proposed, and novel technologies such as proteomics and mitochondrial analysis have been developed. In this review, the weaknesses of QIM were exposed, and novel methodologies for quality evaluation were presented. The consolidation of these novel methodologies and their use as methods of quality assessment are an alternative to sensory methods, and their understanding enables a more effective fish quality control.
Subject(s)
Fishes , Food Quality , Seafood/analysis , Animals , Food Storage , Humans , Penaeidae , Seafood/microbiology , Seafood/standardsABSTRACT
This study aims to develop and characterize colorimetric indicator films based on chitosan, polyvinyl alcohol and anthocyanins from jambolan fruit (Syzygium cumini) prepared by casting method. The effect of anthocyanin extract on thickness, microstructure, moisture content, solubility in water, hydrophobicity, chemical structure, color and opacity of films was analyzed. In addition, anthocyanins photodegradation in films as well its application to monitoring shrimp freshness was studied. Significant effect (p < 0.05) of anthocyanin extract from jambolan fruit on the thickness and optical properties of the films was observed. Anthocyanin extract from jambolan fruit was efficiently incorporated and dispersed into film. The films containing anthocyanins showed visible changes from red color to blue color when used to monitor shrimp freshness at several temperatures (between -20 °C and 20 °C). This research reports for the first time information regarding the valorization and application of anthocyanins from jambolan fruit as an alternative for food packaging sector.
Subject(s)
Anthocyanins/chemistry , Chitosan/chemistry , Food Preservation , Fruit/chemistry , Polyvinyl Alcohol/chemistry , Seafood , Syzygium/chemistryABSTRACT
Visual assessment is regarded as the gold standard to evaluate meat colour shelf-life, but it is costly and time consuming. To address this issue, this paper aims to evaluate the number of consumers and days of display that are necessaries in order to assess the colour shelf-life of meat, presented with different methods, all using images. Photographs of thirty-six lamb steaks were taken just after cutting (day 0) and on each of the following days until the 14th day of display under standardized conditions. Images were presented in three different manners: 1) with days of display and animals in random order (Random); 2) days of display in sequential and animals in random order (Sequential); and, 3) days of display and animals in sequential order (Animal); they were presented to 211 consumers who evaluated visual acceptability on a 9-point scale. At day zero, visual acceptability scores were the highest in Animal, followed by Sequential, and then by the Random (Pâ¯<â¯.05) method. Scores decreased over time for all methods tested (Pâ¯<â¯.05). The Random method presented the highest standard deviation; however, an increase in standard deviation among consumers along days of display was observed for all methods tested (Pâ¯<â¯.05). Shelf-life determined by regression varied according to the method of presentation (7.83, 7.00 and 7.54â¯days for Random, Sequential and Animal, respectively). A minimum number of 4â¯day points before and 4â¯day points after neutral scores had been reached (scoresâ¯=â¯5.0) were necessary in order to obtain a robust model. The minimum number of required consumers (αâ¯=â¯0.05; dâ¯=â¯0.1 and ßâ¯=â¯0.2 or 0.1) varied according to methodology: it was 81 to 109 consumers for Random, 69 to 92 for Sequential, and 55 to 74 for Animal. Our study indicates that an optimal number of days and evaluators can be calculated depending on the manner of sample presentation. These findings should be taken into account in further studies that aim to balance data reliability with the cost involved in meat colour analyses.
Subject(s)
Consumer Behavior/statistics & numerical data , Red Meat , Animals , Color , Female , Male , Photography , Red Meat/analysis , Red Meat/classification , SheepABSTRACT
Fish quality is conditioned by several factors, among them desensitization methods applied for fish managing and slaughtering. This research used electric shock at different intensities as a desensitization method for cobia (Rachycentron canadum) slaughtering and evaluated its effects over fish quality during refrigerated storage. The experiment was carried out by numbing the fish with electroshock at the intensities of 100, 150 and 200 Volts, and keeping them in refrigerated storage for 21 days. On the cobia, obtained from a commercial fish farm the following physical, chemical and sensorial characteristics as quality variables were evaluated: dielectric properties, rigor index, pH, texture, color, sensorial evaluation of freshness, ATP and degradation catabolites. The experimental design was a 6×3 factorial (6 times of analysis and 3 electroshock intensities). Significant differences (P<0.05) were observed for the analyzed variables, as a consequence of desensitization treatments and of storage time within each treatment. However, the number of variables affected by the treatment was smaller than the number of variables significantly affected by the storage time, and the interaction time×treatment was highly significant within the results reported. The best results for the parameters tested were obtained when the treatment at 150 volts intensity with the majority of analyzed variables held significant differences (P<0.05) among treatments. It was also concluded that cobia can be conserved in refrigerated storage within seven days after slaughtering using electro-narcosis as a method of desensitization.(AU)
A qualidade do pescado está condicionada a diversos fatores, entre eles os métodos de insensibilização. Nesta pesquisa foi utilizado o choque elétrico em diferentes intensidades como método de insensibilização do bijupirá (Rachycentron canadum), e avaliados seus efeitos sobre a qualidade dos peixes resfriados. O experimento foi realizado insensibilizando os peixes com eletrochoque de intensidades de 100, 150 e 200 Volts, e armazenados refrigerados durante 21 dias. Os peixes utilizados foram obtidos de uma piscicultura comercial localizada no litoral norte do estado de São Paulo a cerca de 50km, por via marítima, da cidade de Ubatuba-SP. As variáveis de qualidade dos peixes avaliadas foram características físicas, químicas e sensoriais como medidas dielétricas, índice de Rigor Mortir, pH, textura, cor, avaliação sensorial do frescor, ATP e produtos da degradação. O delineamento experimental utilizado foi um fatorial 6X3, seis tempos de análise e três intensidades de choque elétrico. Foram observadas diferenças significativas (P<0,05) para a maioria das variáveis analisadas, tanto para os tratamentos em relação ao tempo, como também para a influência do tempo de armazenamento dentro de cada tratamento. No entanto, o número de variáveis com significância entre os tratamentos foi menor em relação ao número de variáveis em que houve significância para os tempos de conservação, sendo a interação tempoxtratamento a que obteve significância expressiva dentro dos resultados encontrados. Foram observados os melhores resultados para o tratamento com a intensidade em 150 volts para a maioria das variáveis analisadas em que houve diferenças significativas (p<0,05) entre os tratamentos. Concluiu-se também que o bijupirá pode ser conservado em até sete dias após abate em conservação refrigerada utilizando a eletronarcose como método de insensibilização.(AU)
Subject(s)
Animals , Meat/analysis , Chemical Phenomena , Cooled Foods , Electroshock/veterinary , PerciformesABSTRACT
ABSTRACT: Fish quality is conditioned by several factors, among them desensitization methods applied for fish managing and slaughtering. This research used electric shock at different intensities as a desensitization method for cobia (Rachycentron canadum) slaughtering and evaluated its effects over fish quality during refrigerated storage. The experiment was carried out by numbing the fish with electroshock at the intensities of 100, 150 and 200 Volts, and keeping them in refrigerated storage for 21 days. On the cobia, obtained from a commercial fish farm the following physical, chemical and sensorial characteristics as quality variables were evaluated: dielectric properties, rigor index, pH, texture, color, sensorial evaluation of freshness, ATP and degradation catabolites. The experimental design was a 6×3 factorial (6 times of analysis and 3 electroshock intensities). Significant differences (P<0.05) were observed for the analyzed variables, as a consequence of desensitization treatments and of storage time within each treatment. However, the number of variables affected by the treatment was smaller than the number of variables significantly affected by the storage time, and the interaction time×treatment was highly significant within the results reported. The best results for the parameters tested were obtained when the treatment at 150 volts intensity with the majority of analyzed variables held significant differences (P<0.05) among treatments. It was also concluded that cobia can be conserved in refrigerated storage within seven days after slaughtering using electro-narcosis as a method of desensitization.
RESUMO: A qualidade do pescado está condicionada a diversos fatores, entre eles os métodos de insensibilização. Nesta pesquisa foi utilizado o choque elétrico em diferentes intensidades como método de insensibilização do bijupirá (Rachycentron canadum), e avaliados seus efeitos sobre a qualidade dos peixes resfriados. O experimento foi realizado insensibilizando os peixes com eletrochoque de intensidades de 100, 150 e 200 Volts, e armazenados refrigerados durante 21 dias. Os peixes utilizados foram obtidos de uma piscicultura comercial localizada no litoral norte do estado de São Paulo a cerca de 50km, por via marítima, da cidade de Ubatuba-SP. As variáveis de qualidade dos peixes avaliadas foram características físicas, químicas e sensoriais como medidas dielétricas, índice de Rigor Mortir, pH, textura, cor, avaliação sensorial do frescor, ATP e produtos da degradação. O delineamento experimental utilizado foi um fatorial 6X3, seis tempos de análise e três intensidades de choque elétrico. Foram observadas diferenças significativas (P<0,05) para a maioria das variáveis analisadas, tanto para os tratamentos em relação ao tempo, como também para a influência do tempo de armazenamento dentro de cada tratamento. No entanto, o número de variáveis com significância entre os tratamentos foi menor em relação ao número de variáveis em que houve significância para os tempos de conservação, sendo a interação tempoxtratamento a que obteve significância expressiva dentro dos resultados encontrados. Foram observados os melhores resultados para o tratamento com a intensidade em 150 volts para a maioria das variáveis analisadas em que houve diferenças significativas (p<0,05) entre os tratamentos. Concluiu-se também que o bijupirá pode ser conservado em até sete dias após abate em conservação refrigerada utilizando a eletronarcose como método de insensibilização.
ABSTRACT
As consumption of fish and fish-based foods increases, non-destructive monitoring of fish freshness also becomes more prominent. Fish products are very perishable and prone to microbiological growth, not always easily detected by organoleptic evaluation. The analysis of the headspace of fish specimens through gas sensing is an interesting approach to monitor fish freshness. Here we report a gas sensing method for monitoring Tilapia fish spoilage based on the application of a single gas sensitive gel material coupled to an optical electronic nose. The optical signals of the sensor and the extent of bacterial growth were followed over time, and results indicated good correlation between the two determinations, which suggests the potential application of this simple and low cost system for Tilapia fish freshness monitoring.
ABSTRACT
Many cities worldwide are established adjacent to estuaries and their catchments resulting in estuarine contamination due to intense anthropogenic activities. The aim of this study was to evaluate if fish living in an estuarine urban waterway were affected by contamination, via the measurement of a suite of biomarkers of fish health. Black bream (Acanthopagrus butcheri) were sampled in a small urban embayment and a suite of biomarkers of fish health measured. These were condition factor (CF), liver somatic index (LSI), gonadosomatic index (GSI), hepatic EROD activity, polycyclic aromatic hydrocarbon (PAH) biliary metabolites, serum sorbitol dehydrogenase (s-SDH) and branchial enzymes cytochrome C oxidase (CCO), and lactate dehydrogenase (LDH) activities. The biomarkers of exposure EROD activity, and pyrene- and B(a)P-type biliary metabolites confirmed current or recent exposure of the fish and that fish were metabolizing contaminants. Relative to a reference site, LSI was higher in fish collected in the urban inlet as was the metabolic enzyme LDH activity. CF, GSI, s-SDH, CCO, and naphthalene-type metabolites were at similar levels in the urban inlet relative to the reference site. PAH biliary metabolite ratios of high-molecular-weight to low-molecular-weight suggest that fish from the urban inlet were exposed to pyrogenic PAHs, likely from legacy contamination and road runoff entering the embayment. Similarly, the sediment PAH ratios and the freshness indices suggested legacy contamination of a pyrogenic source, likely originating from the adjacent historic gasworks site and a degree of contamination of petrogenic nature entering the inlet via storm water discharge. Biomarkers of exposure and effect confirmed that black bream collected in the Claisebrook Cove inlet, Western Australia, are currently exposed to contamination and are experiencing metabolic perturbations not observed in fish collected at a nearby reference site.
Subject(s)
Perciformes/metabolism , Polycyclic Aromatic Hydrocarbons/toxicity , Water Pollutants, Chemical/toxicity , Animals , Bays , Bile/metabolism , Biomarkers/metabolism , Cytochrome P-450 CYP1A1/metabolism , Electron Transport Complex IV/metabolism , Environmental Monitoring , Estuaries , L-Iditol 2-Dehydrogenase/metabolism , L-Lactate Dehydrogenase/metabolism , Liver/metabolismABSTRACT
Objective. To develop a Quality Index Method (QIM) for gutted and ungutted red tilapia from aquaculture ponds. Materials and methods. 40 specimens of gutted red tilapia and 40 ungutted ones were located in foam polyethylene boxes within layers of ice and storage at 4°C. Three fish were randomly sampled on days 0, 3, 5, 8, 11, 14 and 17 for gutted tilapia, and on days 0, 3, 6, 9, 11, 14 and 16 for ungutted tilapia. A sensorial panel of 8 experts was formed to evaluate the product. With three samples each day with average points of the sensorial attributes proposed in the method, the quality index for gutted and ungutted red tilapia was obtained based on the storage time on ice. Results. The Quality Index Method obtained for gutted and ungutted red tilapia showed maximum values of 21 and 29, respectively. It was adjusted in an increasing lineal model with high correlation between the Quality Index and the storage time on ice. Conclusions. The developed model is useful to determine deterioration levels and to define storage and consumption time. For gutted red tilapia the panel rejected the fish after 8 - 11 days of storage whereas the ungutted red tilapia was rejected after 6 - 9 days.
Objetivo. Desarrollar los esquemas del Método de Índice de Calidad (MIC) para la tilapia roja de piscifactoría eviscerada y sin eviscerar. Materiales y métodos. 40 especímenes de tilapia roja eviscerados y 40 sin eviscerar, fueron ubicados en cajas de polietileno expandido entre capas de hielo y almacenadas a 4°C; se realizaron muestreos los días 0, 3, 5, 8, 11, 14 y 17 para tilapia eviscerada, mientras en la tilapia sin eviscerar los días 0, 3, 6, 9, 11, 14 y 16; se conformó un panel de 8 expertos para la evaluación sensorial de tres ejemplares en cada día de muestreo; con los puntajes promedio de los atributos sensoriales propuestos en el esquema, se obtuvo el índice de calidad para la tilapia roja eviscerada y sin eviscerar en función del tiempo de almacenamiento en hielo. Resultados. Los esquemas del Método índice de Calidad desarrollados para tilapia roja entera eviscerada y sin eviscerar, obtuvieron valores máximos de Índice de Calidad de 21 y 29 puntos respectivamente, ajustados a un modelo lineal creciente con alta correlación entre el Índice de Calidad y el tiempo de almacenamiento en hielo. Conclusiones. Los esquemas del MIC desarrollados son útiles para determinar el nivel de deterioro y definir los tiempos de almacenamiento y consumo. En la tilapia roja eviscerada los panelistas rechazaron el pescado para consumo entre los días 8 y 11 de almacenamiento, mientras que para la tilapia sin eviscerar el producto fue rechazado entre los días 6 y 9 de almacenamiento.
ABSTRACT
O objetivo do presente trabalho foi avaliar o frescor microbiológico de filés sem pele de tilápia do Nilo (Oreochromis niloticus), cultivada durante o seu armazenamento em gelo. Os filés com peso médio de 120g foram acondicionados em caixas isotérmicas, com gelo em escama, na proporção de 1:1 (filé: gelo). Estas caixas foram armazenadas em uma câmara fria, com temperatura externa e interna de aproximadamente 4°C e 0ºC, respectivamente. Realizaram-se análises microbiológicas a cada 72 horas, a partir do tempo zero, em triplicata. A qualidade microbiológica das amostras de tilápia foi aceitável durante o armazenamento.
The objective of this study was to evaluate the microbiological freshness of Nile tilapia (Oreochromis niloticus) skinless fillets, during storage in ice. The average weight of 120g fillets were packed in cool boxes with scale ice, 1:1 ratio (fillet: ice). These boxes were stored in a cold room with internal and external temperature of about 4°C and 0°C, respectively. Microbiological analyzes were performed every 72 hours from time zero in triplicate. The microbiological quality of the tilapia samples was acceptable during storage.
ABSTRACT
O objetivo do presente trabalho foi avaliar o frescor microbiológico de filés sem pele de tilápia do Nilo (Oreochromis niloticus), cultivada durante o seu armazenamento em gelo. Os filés com peso médio de 120g foram acondicionados em caixas isotérmicas, com gelo em escama, na proporção de 1:1 (filé: gelo). Estas caixas foram armazenadas em uma câmara fria, com temperatura externa e interna de aproximadamente 4°C e 0ºC, respectivamente. Realizaram-se análises microbiológicas a cada 72 horas, a partir do tempo zero, em triplicata. A qualidade microbiológica das amostras de tilápia foi aceitável durante o armazenamento.(AU)
The objective of this study was to evaluate the microbiological freshness of Nile tilapia (Oreochromis niloticus) skinless fillets, during storage in ice. The average weight of 120g fillets were packed in cool boxes with scale ice, 1:1 ratio (fillet: ice). These boxes were stored in a cold room with internal and external temperature of about 4°C and 0°C, respectively. Microbiological analyzes were performed every 72 hours from time zero in triplicate. The microbiological quality of the tilapia samples was acceptable during storage.(AU)
Subject(s)
Animals , Food Storage , Food Preservation , Cichlids , Fishes , Ice , Microbiological TechniquesABSTRACT
O Método do Índice de Qualidade é um sistema de controle de qualidade do frescor do pescado e baseia-se na avaliação objetiva dos principais atributos sensoriais de cada espécie de peixe, através de um sistema de pontos de demérito. O MIQ é baseado na avaliação visual e olfativa de certos atributos do peixe, principalmente a aparência dos olhos, pele e brânquias, juntamente com o odor e textura, através de um sistema de classificação por pontos de demérito, de 0 a 3. A pontuação de todos os atributos é somada para dar uma pontuação global sensorial, o chamado Índice de Qualidade (IQ). O método permite a avaliação da qualidade do pescado em questão, a previsão da validade comercial da espécie estudada, com a vantagem de ser barato, simples, requerer pouco treinamento em relação aos outros métodos e não destruir a amostra. Sua aplicação faz da análise sensorial, tão importante para avaliação do frescor do pescado, um método objetivo, permitindo de forma confiável e rápida, a avaliação da matéria-prima, seja a bordo das embarcações, no controle da matéria-prima nas indústrias, ou nos entrepostos e em postos de venda.
The quality index method is a system of quality control and freshness of the fish based on objective assessment of the key sensory attributes of each species of fish, through a system of demerit points. The QIM is based on evaluation of certain visual and olfactory attributes of the fish, especially the appearance of the eyes, skin and gills, odor and texture, using a rating system demerit points, 0 to 3. The scores of all attributes are added to give an overall sensory score, called the Quality Index (QI). The method allows the evaluation of the quality of the fish in question, the prediction of the commercial validity of the species studied, with the advantage of being inexpensive, simple, requires little training compared to other methods and does not destroy the sample. Its application has the sensory analysis, as important assessment of the freshness of the fish, an objective method that allows fast and reliab evaluation of raw material at board vessels, in quality control of raw materials for industry, or at warehouses and retail outlets.
ABSTRACT
The quality index method is a system of quality control and freshness of the fish based on objective assessment of the key sensory attributes of each species of fish, through a system of demerit points. The QIM is based on evaluation of certain visual and olfactory attributes of the fish, especially the appearance of the eyes, skin and gills, odor and texture, using a rating system demerit points, 0 to 3. The scores of all attributes are added to give an overall sensory score, called the Quality Index (QI). The method allows the evaluation of the quality of the fish in question, the prediction of the commercial validity of the species studied, with the advantage of being inexpensive, simple, requires little training compared to other methods and does not destroy the sample. Its application has the sensory analysis, as important assessment of the freshness of the fish, an objective method that allows fast and reliab evaluation of raw material at board vessels, in quality control of raw materials for industry, or at warehouses and retail outlets.
O Método do Índice de Qualidade é um sistema de controle de qualidade do frescor do pescado e baseia-se na avaliação objetiva dos principais atributos sensoriais de cada espécie de peixe, através de um sistema de pontos de demérito. O MIQ é baseado na avaliação visual e olfativa de certos atributos do peixe, principalmente a aparência dos olhos, pele e brânquias, juntamente com o odor e textura, através de um sistema de classificação por pontos de demérito, de 0 a 3. A pontuação de todos os atributos é somada para dar uma pontuação global sensorial, o chamado Índice de Qualidade (IQ). O método permite a avaliação da qualidade do pescado em questão, a previsão da validade comercial da espécie estudada, com a vantagem de ser barato, simples, requerer pouco treinamento em relação aos outros métodos e não destruir a amostra. Sua aplicação faz da análise sensorial, tão importante para avaliação do frescor do pescado, um método objetivo, permitindo de forma confiável e rápida, a avaliação da matéria-prima, seja a bordo das embarcações, no controle da matéria-prima nas indústrias, ou nos entrepostos e em postos de venda.
ABSTRACT
The quality index method is a system of quality control and freshness of the fish based on objective assessment of the key sensory attributes of each species of fish, through a system of demerit points. The QIM is based on evaluation of certain visual and olfactory attributes of the fish, especially the appearance of the eyes, skin and gills, odor and texture, using a rating system demerit points, 0 to 3. The scores of all attributes are added to give an overall sensory score, called the Quality Index (QI). The method allows the evaluation of the quality of the fish in question, the prediction of the commercial validity of the species studied, with the advantage of being inexpensive, simple, requires little training compared to other methods and does not destroy the sample. Its application has the sensory analysis, as important assessment of the freshness of the fish, an objective method that allows fast and reliab evaluation of raw material at board vessels, in quality control of raw materials for industry, or at warehouses and retail outlets.
O Método do Índice de Qualidade é um sistema de controle de qualidade do frescor do pescado e baseia-se na avaliação objetiva dos principais atributos sensoriais de cada espécie de peixe, através de um sistema de pontos de demérito. O MIQ é baseado na avaliação visual e olfativa de certos atributos do peixe, principalmente a aparência dos olhos, pele e brânquias, juntamente com o odor e textura, através de um sistema de classificação por pontos de demérito, de 0 a 3. A pontuação de todos os atributos é somada para dar uma pontuação global sensorial, o chamado Índice de Qualidade (IQ). O método permite a avaliação da qualidade do pescado em questão, a previsão da validade comercial da espécie estudada, com a vantagem de ser barato, simples, requerer pouco treinamento em relação aos outros métodos e não destruir a amostra. Sua aplicação faz da análise sensorial, tão importante para avaliação do frescor do pescado, um método objetivo, permitindo de forma confiável e rápida, a avaliação da matéria-prima, seja a bordo das embarcações, no controle da matéria-prima nas indústrias, ou nos entrepostos e em postos de venda.
ABSTRACT
A lagosta tem papel de destaque no setor pesqueiro nacional, sendo o principal recurso pesqueiro da região Nordeste e 95% desta produção destina-se ao mercado internacional. O grau de frescor do pescado é um dos aspectos mais importantes para determinar a qualidade do pescado, e frequentemente se recorre a métodos sensoriais, físicos, bioquímicos e microbiológicos. O objetivo deste trabalho foi avaliar a qualidade da lagosta inteira armazenada em gelo através do Método de Índice de Qualidade (MIQ), que permite a determinação rápida e eficiente do grau de frescor do pescado. Os pontos de deméritos foram designados aos atributos sensoriais selecionados de acordo com sua importância. Durante o armazenamento foram realizadas determinações do Nitrogênio das Bases Voláteis Totais (NBVT), pH e análises microbiológicas (Coliformes Termotolerantes, Salmonella spp. e Staphylococcus aureus). O Índice de Qualidade (IQ) variou de zero (máximo frescor) a 14 (perda total do frescor) atingindo o limite de aceitabilidade para consumo (IQ = 6,3), o que equivale a um período de 7 dias. O valor do N-BVT variou de 19,69 a 29,63 mg 100g-1, e o pH variou de 6,91 a 7,03 no primeiro e 17º dia de armazenamento, respectivamente. Os resultados microbiológicos atenderam aos padrões microbiológicos estabelecidos pela legislação brasileira.
The lobster has an important role in the national fisheries sector, the main fishing resourc e in the Northeast and 95% of this production is intended for the international market. The seafood freshness degree is one of the most important in determining the seafood quality, and often uses a sensorial, physical, biochemical and microbiological methods. The objective of this study was to evaluate the whole lobster quality stored on ice through the Quality Index Method (QIM), which allows rapid and efficient determination of the seafood freshness. The demerits points were assigned to the sensory attributes selected according to their importance. During storage the total volatile bases nitrogen (TVB - N), pH and microbiological (fecal coliform, Salmonella spp. and Staphylococcus aureus ) were made. The Quality Index (IQ) ranged from zero (maximum freshness) to 14 (total loss of freshness) reached the acceptable limit for consumption (IQ = 6.3), which corresponds to a period of 7 days. The value of the TVB - N ranged from 19.69 to 29.63 mg 100g - 1 , and the pH ranged from 6.91 to 7.03 in the first and 17th day of storage, respectively. The microbiological results met the microbiological standards e stablished by Brazilian legislation.
Subject(s)
Animals , Cooled Foods , Palinuridae/physiology , Food Quality , Microbiological Techniques/methods , Food Storage , Food PreservationABSTRACT
A carne de pescado possui uma constituição química peculiar que lhe confere riqueza nutricional, porém com alto potencial de deterioração. Neste contexto, os benefícios nutricionais deste grupo alimentar só podem ser aproveitados quando os fatores segurança e qualidade forem garantidos, tornando-se fundamental o emprego de ferramentas que possam agir na contenção dos mecanismos de deterioração, como o emprego da cadeia do frio em todas as etapas do seu processamento. O presente artigo teve o objetivo de reunir as informações relevantes relatadas na literatura sobre pescado, suas características gerais, mecanismos de deterioração e métodos de avaliação da qualidade. (AU)
The seafood flesh has a peculiar chemical constitution which provides nutritional riches, but it shows a high deteriorating potential. In this context, the nutritional benefits of this food group can be put to good use only after guaranteeing the product safety and quality. Therefore, the use of tools for slowing the deteriorative mechanisms down has been crucial, such as the cold chain application in all of the seafood processing stages. This study is aimed at collecting relevant data on seafood from specific scientific literature concerning its general characteristics, deterioration mechanisms and quality evaluation methodologies. (AU)
Subject(s)
Food Contamination , Food Handling , Fishes , Food QualityABSTRACT
O pescado é um grupo de alimentos com elevado potencial de deterioração e, por essa razão, é fundamental o emprego de ferramentas de avaliação do frescor destes produtos. O objetivo do presente trabalho foi desenvolver o Método do Índice de Qualidade (MIQ) para a tilápia do Nilo (Oreochromis niloticus), nas formas inteira, eviscerada e em filé, armazenada em gelo e aplicá-lo no estabelecimento da sua vida útil. Neste sentido, realizaram-se três experimentos simultâneos. Nos experimentos I, II e III, foi desenvolvido o MIQ para a tilápia do Nilo inteira, tilápia inteira eviscerada e filés sem pele, respectivamente. Exemplares de tilápia de Nilo, com aproximadamente 650g, foram separados em três lotes, e colocados em caixas isotérmicas com gelo na proporção de 1:1, cada caixa continha 36 peixes, que correspondiam às amostras de cada experimento. As caixas foram armazenadas sob refrigeração, com temperatura externa de aproximadamente 4°C e interna de 0°C. A avaliação do frescor das amostras de peixes durante o armazenamento foi realizada através de análises sensoriais (MIQ), físico-químicas (pH e N-BVT) e microbiológicas (contagem bacteriana total, contagem de micro-organismos psicrotróficos, contagem de Staphylococcus aureus e número mais provável de coliformes totais e termotolerantes) a cada 72 horas, a partir do tempo zero. As análises foram realizadas com três repetições. A análise sensorial foi realizada por julgadores previamente treinados. O fim do período de armazenamento foi determinado pela análise sensorial, quando as amostras receberam a pontuação de IQ máxima. O ponto de rejeição pelo MIQ foi atingindo aos 9, 18 e 15 dias, respectivamente, para as tilápias nas formas inteira, eviscerada e em filé. As contagens microbiológicas dos peixes durante o armazenamento não ultrapassaram os limites preconizados pela ICMSF e ANVISA.[...]
Fish is a food group with high potential for deterioration and for this reason it is fundamental the use of tools to assess the freshness of these products. The objective of this study was develop the Quality Index Method (QIM) for farmed Nile tilapia (Oreochromis niloticus), and apply it in the establishment of its useful life. In this sense, three simultaneous experiments were done. For experiments I, II and III QIM were developed for whole, whole and gutted and skinned fillets. The fishes, containing approximately 650 g, were separated into three batches, and placed in cool boxes with ice in a 1:1 ratio, each box contained 36 copies, which correspond to samples of each experiment. The boxes were stored at refrigeration temperature (4°C - external and 0°C internal). To evaluate the freshness during storage, sensory analysis (QIM), physicochemical (pH and TVB-N) and microbiological (total bacterial count, psychrotrophic count, Staphylococcus aureus and most probable number of total coliforms and thermotolerant) were done every 72 hours from zero time. Analyses were performed with three replicates. Sensory analysis was performed using the QIM by a team consisting of panelists previously trained. The end of the storage period was determined by sensory analysis, when samples received the highest IQ scores. The point of rejection by the QIM was reached 9, 18 and15 days for whole tilapia, whole and gutted tilapia and tilapia fillet, respectively. The microbiological counts of fish during storage did not exceed the limits recommended by the ICMSF and ANVISA. [...]
Subject(s)
Animals , Frozen Foods , Food Storage , Meat/analysis , Cichlids/anatomy & histology , Quality Control , Food QualityABSTRACT
The objective of this study was to develop the Quality Index Method (QIM) for skinned fillets from farmed Nile tilapia (Oreochromis niloticus), and apply it in the establishment of its shelf life. The skinned fillets (120 g in average) were kept in boxes with ice in the proportion of 1:1 (fillet:ice) under average temperature of 0C and stored at refrigeration chamber (4C) during 18 days. To evaluate the freshness during storage time sensory analysis (QIM) and physicochemical (pH and TVB-N) were performed every 72 hours from time zero, in triplicate. The maximum life of the Nile tilapia fillet in ice was estimated at 15 days. The MIQ was considered effective in evaluating the freshness of the Nile tilapia, since the sensory rejection by MIQ was determinant in the shelf life establishment.
O objetivo do presente trabalho foi desenvolver o Método do Índice de Qualidade (MIQ) para filé sem pele de tilápia do Nilo (Oreochromis niloticus), cultivada, e aplicá-lo no estabelecimento da sua vida útil. Os filés (média de 120 g cada) foram mantidos em caixas com gelo na proporção de 1:1 (filé:gelo) na temperatura média de 0C e armazenados em câmaras de refrigeração (4C) por 18 dias. Para avaliar o frescor durante o armazenamento, realizaram-se análises sensoriais (MIQ) e físico-químicas (pH e Nitrogênio das Bases Voláteis Totais) a cada 72 horas, a partir do tempo zero, em triplicata. A vida útil máxima do filé sem pele de tilápia do Nilo, em gelo, foi estimada em 15 dias. O MIQ foi considerado eficiente na avaliação do frescor da tilápia do Nilo, já que a rejeição sensorial pelo MIQ foi determinante no estabelecimento da vida de prateleira.
ABSTRACT
The objective of this study was to develop the Quality Index Method (QIM) for skinned fillets from farmed Nile tilapia (Oreochromis niloticus), and apply it in the establishment of its shelf life. The skinned fillets (120 g in average) were kept in boxes with ice in the proportion of 1:1 (fillet:ice) under average temperature of 0C and stored at refrigeration chamber (4C) during 18 days. To evaluate the freshness during storage time sensory analysis (QIM) and physicochemical (pH and TVB-N) were performed every 72 hours from time zero, in triplicate. The maximum life of the Nile tilapia fillet in ice was estimated at 15 days. The MIQ was considered effective in evaluating the freshness of the Nile tilapia, since the sensory rejection by MIQ was determinant in the shelf life establishment.
O objetivo do presente trabalho foi desenvolver o Método do Índice de Qualidade (MIQ) para filé sem pele de tilápia do Nilo (Oreochromis niloticus), cultivada, e aplicá-lo no estabelecimento da sua vida útil. Os filés (média de 120 g cada) foram mantidos em caixas com gelo na proporção de 1:1 (filé:gelo) na temperatura média de 0C e armazenados em câmaras de refrigeração (4C) por 18 dias. Para avaliar o frescor durante o armazenamento, realizaram-se análises sensoriais (MIQ) e físico-químicas (pH e Nitrogênio das Bases Voláteis Totais) a cada 72 horas, a partir do tempo zero, em triplicata. A vida útil máxima do filé sem pele de tilápia do Nilo, em gelo, foi estimada em 15 dias. O MIQ foi considerado eficiente na avaliação do frescor da tilápia do Nilo, já que a rejeição sensorial pelo MIQ foi determinante no estabelecimento da vida de prateleira.