Resumen Introducción: Sardina (Sardinha pilchardus) es una especie pelágico, das Clupeidae, siendo un dos peces más abundantes del mundo. El término "calidad" engloba el índice de evaluación de frescura según Reg. (CE) nº 2406/96 del Consejo, de 26 de noviembre, lo que se refiere a la apariencia estética y frescura, o al grado de deterioro que ha sufrido el pescado. Objetivo: Evaluar el grado de frescura, calidad higiénica y composición bromatológica de las sardinas en diferentes superficies comerciales en Beja, Alentejo. Métodos: Se llevaron a evaluación cuatro lotes diferentes de sardinas de las diferentes superficies comerciales (20 sardinas/lote), de acuerdo con las tablas de clasificación de frescura en el Reg. (CE) nº 2406/96 del Consejo, de 26 de noviembre. Se realizó análisis físico-químico: determinación de nitrógeno básico volátil (NBVT), de índice de refracción (IR) de humor acuoso, de pH, color, textura, composición bromatológico, y análisis microbiológicas. Resultados: Los valores de NBVT para las muestras presentado valores abajo de 14 mg/100g, segundo Reg. (CE) 1022/2008 deben ser abajo de 20 - 30mg/100g, por lo que los 4 lotes cumplen los criterios de calidad. Los análisis microbiológicos se encontraban dentro de los parámetros aceptables de calidad microbiológica. Los valores nutricionales se presentaron de 161 Kcal/100g, ligeramente abajo de los valores de la tabla de referencia alimentar del INSA (2007), dada la época del año (Primavera) presentaron bajo contenido de grasa. Conclusión: Las sardinas presentaron clasificación de frescura de Extra y A, evidenciando un estado satisfactorio para el consumo. Los análisis más aclaratorios para la determinación de la frescura fueron la cuantificación de NBVT así como la textura instrumental y la determinación del IR.

Resumo Introdução: A Sardinha (Sardinha pilchardus) é uma espécie pelágica, da família das Clupeidae, sendo um dos peixes mais abundante em todo o mundo. O termo qualidade em pescado referre-se ao índice de avaliação de frescura de acordo o Reg. (CE) nº 2406/96 do Conselho, de 26 de novembro, nomeadamente à aparência estética, frescura, e grau de alteração sofrido pelo pescado. Objetivo: Avaliar o grau de frescura, qualidade higiénica e a composição bromatológica de sardinhas, em diferentes superfícies comerciais de Beja, Alentejo. Métodos: Avaliaram-se 4 lotes diferentes de Sardinha pilchardus provenientes de 4 superfícies comerciais (20 sardinhas/lote), classificaram-se de acordo as tabelas do Reg. (CE) nº 2406/96. Efetuaram-se análises físico-químicas: Azoto básico volátil (ABVT), Índice de refração (IR) do humor aquoso, pH, cor, textura, composição bromatológica e parâmetros microbiológicos. Resultados: Os valores de ABVT para as diferentes amostras apresentam valores abaixo de 14 mg/100g, segundo o Reg. (CE) 1022/2008 deve estar abaixo de 20 a 30mg/100g, pelo que os 4 lotes cumprem o critério. As análises microbiológicas apresentaram valores aceitáveis. As sardinhas apresentam valores médios de 161 Kcal/100g, ligeiramente abaixo dos valores da tabela alimentar do INSA (2007), dada a época do ano (Primavera) apresentaram gordura baixa. Conclusão: As sardinhas apresentaram uma categoria de frescura de Extra e A, evidenciando um estado satisfatório para consumo. As determinações que se revelaram mais fiáveis para a determinação da frescura foram o ABVT, a textura instrumental e o IR.

Abstract Introduction: Sardine (Sardinha pilchardus) is pelagic specie, from Clupeidae family, being one of the most abundant fishes all over the world. The term "quality" in fish refers to the index of freshness evaluation in accordance to the Regulation (EC) No. 2406/96 of November 26th, namely the esthetical appearance, freshness and degree of deterioration that the fish had suffered. Objective: To evaluate the freshness index, hygienic quality and bromatological composition of sardines in different commercial shops in Beja, Alentejo. Methods: Four different lots of Sardinha pilchardus were evaluated from the four commercial shops (20 sardines/lots), and classification was made of the category of each of the lots was carried out by the Reg. (EC) No. 2406/96 tables. Physical-chemical analysis was made: determination of Total Volatile Basic Nitrogen (TVB-N), refractive index of vitreous humor (RI), pH, colour, texture, bromatological analysis, and microbiological analysis. Results: TVB-N values for the different samples was lower than 14 mg/100g, as mentioned in Reg. (EC) No 1022/2008 it should be lower than 20 to 30mg/100g, and therefore the 4 samples respected that criteria. Microbiological analysis showed that the samples were within the acceptable values. The sardines presented average nutritional values of 161 Kcal/100g, which are lower than reference values from INSA (2007) nutritional table, eventually due to the low fat content by this time of the year (Spring). Conclusion: The sardines showed freshness categories of Extra and A, and hence emphasized a satisfactory state for consumption. The most expounding analyzes for the determination of freshness were the TVB-N, the instrumental texture and the Refraction Index.

Abstract The nanosilver food packaging films were developed by polyvinyl alcohol activated with Satureja rechingeri extract (S-AgNPs/PVA) using the solvent casting to evaluate the freshness of Oncorhynchus mykiss fillets during 14 days at the refrigerated temperature. The 160 pieces of fish were enfolded in 4 types of films as main group-series. The main components of the extract were carvacrol (83.2%) p-cymene (3.11%), thymol (2.13%) and γ-terpinene (1.63%). The UV-Vis and TEM evaluations of S-AgNPs showed that the size of S-AgNPs was mostly smaller than 55 nm in diameter. Mesophilic and psychrophilic bacteria counts were remarkably less than 6.0 log CFU/g about 2.1, 1.3 log CFU/g and 2.0, 1.0 log CFU/g, respectively for fish samples wrapped in S-AgNP/Ult.PVA (Ultrasound method) and S-AgNP/Pho.PVA (Photochemical method) preserved at 4 °C on the 7th day. S-AgNP/Ult.PVA and S-AgNP/Pho.PVA showed strong efficiency in complete eliminating S. aureus and psychrophilic bacteria from coated trout samples than E. coli and mesophiles. It is suggested that AgNP/Ult.PVA and S-AgNP/Pho.PVA films can be used as nanocomposite film for fish preservation at refrigerated temperature to postpone the spoilage up to 7th day.

Abstract Smart film from jackfruit seeds containing anthocyanin extract has potential application as a freshness indicator of fish as they deteriorate, changing the color as a function of the product pH. The lower solubility percentage of the films was evidenced by the lower anthocyanin extract volume. The films presented mean water vapour permeability values of 3.034 g.mm/kPa.h.m2. The starch/anthocyanin film (ST4.0:AN5.0) showed higher tensile strength, while ST2.4:AN5.0 and ST3.0:AN5.3 showed lower resistance. A small change in color in the films was evidenced after 48 hours, and fish (FF10) presented a blue color after 146 hours with a reduction in a* values. Shrimp (SF10) presented negative b* values and grayish color. The indicator film provides an alternative for a convenient, non-destructive and easy-to-view method, as well as informing consumers about the quality of the packaged product. The indicator function of the film was positive, suggesting the potential use of industry co-products in developing smart food freshness indicator packaging.

Abstract Willing to increase the shelf life of the food matrix, studies regarding new preservations methods are developed to preserve fish deterioration. The application of natural additives as preservatives is increasingly common, with a current emphasis on the growing use of protein hydrolysates, in substitution to artificial ones. These compounds have been the subject of recent studies, focusing on determining their functional properties and the best form of applying peptide chains. The present study aimed to evaluate the effects of the protein hydrolysate obtained by the enzymatic hydrolysis of commercial fish gelatin added to rainbow trout fillets (Oncorhynchus mykiss) packed under vacuum and maintained under refrigeration. The fillets were distributed into three sample groups (controls and hydrolysate addition at 1:10 and 1:1 ratios). Microbiological and physico-chemical assessments were carried out. The results were compared and correlations observed regarding fish preservation assessments. A relationship between pH, redox potential and N-TVB was verified when compared to microbial development, especially with regard to psychrotrophic aerobic heterotrophic bacteria count. It was concluded that the application of protein hydrolysate as an additive is promising and can be effective in the control of food quality and maintenance of freshness for a longer period.

Abstract Objectives: The first one identifies the socio-economic profile of the population of Loma Bonita, Oaxaca (occupation, schooling, gender, age and income) and its relevance for a king prawn´s (Macrobrachium acanthuru) consumer in the area. The second one, determines the role that certain attributes such as freshness and size play in the weighting of the king prawn´s shrimp buyer. Methodology: The statistical techniques applied were the principal component analysis and the Conjoint Analysis. Results: Show that consumers look for a very fresh product, whose size exceeds 13 centimeters and is offered in the market at an average price of 140 pesos (kilogram). Another interesting result is that the consumption of chicken meat, among the surveyed population, ispositioned first in the center of the consumption of meat, poultry and fish and that the latter are considered as a competitive good of the king prawn. Limitations: The main limitation of this work lies in the rigidity of the conjoint method by limiting the possibility that the consumer evaluates some other factor not considered since the initial proposal. Conclusions: It was found that both consumer profiles found form two possible marketing target groups, the nearest competitor to fish is prawn and consumer preferences are inclined towards on a very fresh product, whose size exceeds 13 cm and it is offered on the market at a price of 140 pesos.

Resumen Objetivos: El primero, identifica el perfil socio-económico de la población de Loma Bonita, Oaxaca (ocupación, escolaridad, genero, edad e ingresos) con la intención de ponderar su relevancia como características que determinan sus preferencias en el consumo de langostino (Macrobrachium acanthurus). El segundo, determina el rol que juegan atributos tales como la frescura y el tamaño del langostino en la ponderación que realiza el comprador. Metodología: La metodología aplicada fue el Análisis de Componentes Principales y el Análisis Conjoint. Resultados: Muestran preferencias hacia un producto muy fresco, cuya talla sobrepase los 13 centímetros y se ofrezca en el mercado a un precio promedio de 140 pesos (kilogramo). Otro resultado interesante es que el consumo de carne de pollo, entre la población encuestada, se posiciona en primer lugar dentro del consumo de carnes, aves y pescados y que estos últimos son considerados como un bien competitivo del langostino. Limitaciones: La principal limitante de este trabajo radica en la rigidez del método conjoint al limitar la posibilidad de que el consumidor evalúe algún otro factor no considerado desde la propuesta inicial. Conclusiones: Los dos perfiles del consumidor encontrados son dos posibles nichos de mercados, que el competidor más cercano es el pescado y que las preferencias están inclinadas sobre un producto muy fresco, cuya talla sobrepase los 13 centímetros y se ofrezca en el mercado a un precio de 140 pesos.

Abstract The effect of different concentrations of gelatin (0%, 2.5%, and 5%) and vacuum packaged on the preservation of golden pompano (Trachinotus blochii) fillets stored at 4 °C was studied over 14 days. The results suggested that both the gelatin groups (2.5% and 5%) showed a reduction in deterioration of colour, drip loss and texture compared to the control group (0%). In addition, the gelatin coating caused a slower reduction in the freshness indexes of the fish, such as total volatile base nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), total viable counts and pH. During a certain storage period, the gelatin notably prevented the deterioration of the golden pompano fillet at 4 °C. The 5% gelatin group showed the best effect on preserving the freshness indexes. Thus, the application of gelatin as a preservative is highly prospective for the preservation of fish fillets.

Abstract Overall objective of the study was assessment for freshness parameters of gilthead seabream (Sparus aurata). The freshness was determined by two conventional method (i.e. Minolta color measurement method) was compared with a novel machine vision technology (i.e image color analysis method). The quality characteristics related to the freshness of the fresh fish are traditionally based on the color measurements of the whole fish by using Minolta color measurement method. This study aimed to compare the use of the image analysis method to see whether the freshness of seafood can be measured more accurately. Our analysis proved more exact and reliable results in the freshness evaluation of the Sparus aurata based on the color changes in the eyes, gill and skin of the fish. This study revealed that image analysis can be successfully used for the assessment of fish freshness by measuring the color parameters of images captured from skin, gill and eye of the fish during cold storage. It is easy and practical to use image color analysis method in the quality control evaluation of fish freshness measurement. This analysis method can be suitable for use in continuous process at the seafood processing factories (e.g. before packaging to sort out fresh vs old fish automatically).

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: 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 O objetivo desta pesquisa foi comparar os atributos de qualidade de barrinhas temperadas de beijupirá embaladas a vácuo e em atmosfera modificada (MAP), sob temperatura de refrigeração, bem como estabelecer a mistura de gás mais adequada para manter o frescor do produto e a vida de prateleira mais extensa. As barrinhas temperadas de beijupirá foram empanadas com uma mistura de especiarias desidratadas (salsa, cebola, alho, tomate e bacon), embaladas sob vácuo; 100% aeróbico (controle, na presença do ar atmosférico); MAP1 (15% N2 + 80% CO2 + 5% O2); MAP2 (20% N2 + 70% CO2 + 10% O2), e armazenada a 5°C durante 28 dias. A cada 72 horas, amostras foram retiradas, em triplicata, para as análises microbiológicas (contagem total de bactérias mesófilas, contagem total de bactérias psicrotróficas, Staphylococcus coagulase positiva, Salmonella sp., e coliformes termotolerantes a 45°C) e análises físico-químicas (pH, nitrogênio de bases voláteis totais e trimetilamina). Os resultados mostraram que as barrinhas temperadas de beijupirá permaneceram seguras e com qualidade microbiológica e físico-química por um longo período de tempo quando embalados em atmosfera modificada. O grupo MAP1 (15% N2 + 80% CO2 + 5% O2 ) foi o que apresentou melhor desempenho na manutenção da qualidade e frescor, sendo o mais adequado demonstrando sua viabilidade em garantir a qualidade e maior prazo de validade (28 dias) a 5°C.

Abstract The objective of this research was to compare the quality attributes of seasoned cobia sticks packed under vacuum and using modified atmosphere packaging (MAP) and stored under refrigeration, as well as to establish the most suitable gas mixtures to maintain product freshness and provide an extended shelf life. The seasoned cobia sticks were breaded with a mixture of dehydrated spices (parsley, onion, garlic, tomato and bacon), packaged under vacuum; 100% aerobic package (control, with the presence of atmosphere air); MAP1 (15% N2 + 80% CO2 + 5% O2), and MAP2 (20% N2 + 70% CO2 + 10% O2 ), and stored at 5°C for 28 days. Samples were taken every 72 hours for the microbiological analyses (total mesophilic count, total psychrotrophic count, coagulase positive Staphylococcus, Salmonella sp., and thermotolerant Coliforms at 45°C) and physicochemical analyses (pH, the nitrogen from the total volatile bases, and trimethylamine), all carried out in triplicate. The results showed that the seasoned cobia sticks remained safe and with good microbiological, physical and chemical quality for a longer period when packed in a modified atmosphere. MAP1 (15% N2 + 80% CO2 + 5% O2) was the system showing the best performance in the maintenance of quality and freshness, demonstrating the feasibility of ensuring quality and a longer shelf life (28 days) at 5°C.

Abstract Tambaqui is the main fish species farmed in the Amazon. It is produced on industrial scale, slaughtered in the field, primarily by post-harvest asphyxia. This procedure, however, is stressful because it depletes energy reserves that should be used in postmortem metabolism, which may compromise fish meat freshness and quality. The present study compared the quality of tambaquis slaughtered by asphyxia, the conventional industrial method, and hypothermia. Tambaquis weighing around 1.6 kg were harvested from dugout ponds, transported to experimental tanks and allowed to recover from transport stress for 48h. Biological parameters of fish were evaluated alive post- harvest (Harv), transport (Tr) and recovery (Rc), and postmortem analysis was performed in fish slaughtered by asphyxia (Asph) or hypothermia (Hyp) after transport and recovery. Initial observations showed that the content of total volatile nitrogen bases (TVB-N) and pH were higher in fish killed by asphyxia. Sensory analysis indicated that the quality of fish slaughtered immediately after transport was lower than in fish allowed to recover from pre-slaughter stress. The results suggest that recovery from pre-slaughter stress contributes to preserving meat freshness and quality in tambaquis slaughtered on an industrial scale, but other studies are required to determine the feasibility of this recommendation.

Resumo Considerando-se a importância dos esquemas sensoriais para avaliação do frescor das diferentes espécies de peixes e que a carapeba (Eucinostomus gula) é uma importante espécie comercial de peixe marinho na Região Nordeste do Brasil, o objetivo deste estudo foi avaliar o frescor e a vida de prateleira desta espécie durante 18 dias de armazenada em gelo. Alterações durante o armazenamento foram observadas através da avaliação sensorial (Método do Índice de Qualidade - MIQ), das análises físico-químicas (pH e nitrogênio das bases voláteis totais ‒ N-BVT, e da trimetilamina - N-TMA) e das análises microbiológicas (contagem total de mesófilos e psicrotróficos). Alta correlação entre o Índice de Qualidade (IQ) e o tempo de armazenamento foi verificada. Os resultados microbiológicos mostraram um aumento da contagem de mesófilos e psicrotróficos a partir do nono dia de armazenamento. O N-BVT e o N-TMA aumentaram durante o tempo de armazenamento, e o pH aumentou lentamente. Os resultados sugerem que o frescor da carapeba permanece aceitável para consumo pelo resfriamento em gelo até 10 dias.

Abstract Considering the importance of sensory schemes for the evaluation of the freshness of different fish species, and the fact that carapeba (Eucinostomus gula) is an important commercial marine fish species in Northeastern Brazil, the objective of this study was to evaluate the freshness and shelf life of this fish during 18 days stored in ice. Changes during storage were observed according to the sensory evaluation (Quality Index Method - QIM), physicochemical analyses (pH, total volatile basic nitrogen - TVB-N, and trimethylamine - TMA-N) and microbiological analyses (total mesophilic and psychrotrophic counts). High correlation was found between the Quality Index (QI) and storage time. The microbiological results showed increases in the mesophilic and psychrotrophic counts as from the 9th day of storage. The TVB-N and TMA-N both increased during storage and the pH value increased slowly. The results suggested that the fresh carapeba is acceptable for consumption when kept in ice for up to 10 days.

Abstract: This study conducted a comparative analysis of catfish (I. punctatus) and carp (C. carpio) meat used for hamburger elaboration, considering fish impact on the feasibility of manufacturing, organoleptic acceptance, nutritional value, content of microorganisms and its cost. Results indicate that degree of meat freshness and safety of the process prevented pathogenic microorganism presence in the product. Also, identified that species has no influence in obtaining a best burger, nor in their organoleptic acceptance or bromatologic content. Although, matter and energy balance indicates a higher production performance of I. punctatus meat, due that registered the lowest percentage of unused components loss, which provides a greater amount of burgers at a lower cost.

Resumen: El estudio realizó un análisis comparativo de la utilización de la carne de bagre (I. punctatus) y carpa (C. carpio) para la elaboración de hamburguesas, considerando el impacto de la especie en la factibilidad de manufactura, la aceptación organoléptica, el valor nutricional, el contenido de microorganismos y el costo de las mismas. Los resultados indican que el grado de frescura de la carne y la inocuidad del proceso evitaron la presencia de microorganismos patógenos en el producto final. Asimismo, se identificó que la especie no influye en la obtención de una óptima hamburguesa, ni en su aceptación organoléptica o contenido bromatológico. El balance de materia y energía indica un mayor rendimiento de producción con la carne de I. punctatus debido a que registró el menor porcentaje de mermas por componentes no utilizados, lo cual proporciona una mayor cantidad de hamburguesas a un menor costo.

We assessed the degree of freshness of gutted and ungutted red tilapia (Oreochromis ssp) using physicochemical and microbiological analyses of samples of gutted red tilapia on days 0, 3, 5, 8, 11, 14 and 17 and of ungutted red tilapia on days 0, 3, 6, 9, 11, 14 and 16. The total sample size was five fish stored in ice at temperatures between 0 and 4 °C. Different methods were used to study the degree of freshness: pH, water holding capacity (WHC) and microbiological analysis (aerobic mesophilic count). Once we obtained the results, a one-way analysis of variance (ANOVA) was used to determine possible correlations between the values of deterioration and the data obtained by other analysis methods. The one-way ANOVA showed that statistically significant differences (P<0.05) were found in almost all of the parameters analyzed throughout the storage times, indicating the loss of freshness in the fish. In the gutted fish, the firmness of the fillets and the whole fish presented the most noticeable statistically significant deterioration on day eight of storage, when the six logarithmic cycles of aerobic mesophilic bacteria counts were exceeded, and the fillets presented a statistically significant deterioration of the WHC. The ungutted fish began to lose freshness that limited the consumption of the food between the third and sixth day of storage, with aerobic mesophilic bacteria counts of 7.33±1.07 Log CFU g-1 and 7.14±1.60 Log CFU g-1, respectively. Similarly, significant decreases in firmness in the fillets and abdomen were noticed on the third day of storage.

Se evaluó el grado de frescura del producto a través de métodos fisicoquímicos y microbiológicos, realizando un muestreo durante los días 0, 3, 5, 8, 11, 14 y 17 en la Tilapia Roja eviscerada y en los días 0, 3, 6, 9, 11, 14, y 16 en la Tilapia Roja, sin eviscerar, con un tamaño de muestra de cinco peces almacenado en hielo bajo condiciones de refrigeración (0-4 °C). El grado de frescura se estudió a través de diferentes métodos: pH, capacidad de retención de agua (CRA) y análisis microbiológico (recuento de mesófilos aerobios). Obtenidos los resultados, se realizó un análisis de varianza simple (ANOVA) para determinar la posible correlación de los valores de deterioro y los datos obtenidos por métodos analíticos. El análisis de varianza simple arrojó que en casi todos los parámetros evaluados se presentaron diferencias estadísticamente significativas (P≤0.05) a medida que avanzó el almacenamiento, siendo un indicativo de la pérdida de frescura en el pescado. Es así como en la tilapia eviscerada, la evolución de la dureza del filete y del pescado entero, se encontraron descensos estadísticamente significativos más notorios en el octavo día de almacenamiento, momento a partir del cual fueron superados los seis ciclos logarítmicos en recuento de Mesófilos aerobios; este mismo día el filete experimentó un descenso estadísticamente significativo en la CRA. En la Tilapia sin eviscerar, la pérdida de frescura que limita el consumo del alimento se presentó entre los tres y seis días de iniciado el almacenamiento con valores en el recuento de Mesófilos aerobios de 7.33±1.07 Log UFC g-1 y 7.14±1.60 Log UFC g-1, respectivamente; de la misma forma, los descensos significativos en dureza del filete y dureza del vientre se hicieron notorios a partir del tercer día de almacenamiento.

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.

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.

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.