Impact of Cooking Conditions on Proximate Composition and Textural Properties of Chicken Breast Meat

The aim of this study was to evaluate the impact of cooking conditions on proximate composition and textural properties (cohesiveness and chewiness) of chicken breast meat. Eight packs of industrial skinless chicken breast meat were cooked by air frying (AF), baking (BK), deep fat frying (DF) and grilling (GR) at 170, 180 and 190oC for 0, 4, 8, 12 and 16 min. The chicken breast packs were frozen and sliced into dimensions, thawed, cooked and analysed by a two way analysis of variance. The results revealed that cooking methods significantly (p < 0.05) decreased moisture and protein contents from 75.14 to 58.25 % and 89.17 to 82.98 %, but increased fat content from 4.26 to 7.78 %, ash content from 1.95 to 2.39 %, carbohydrate content from 4.63 to 6.95 %, cohesiveness content from 0.40 to 0.52 and chewiness value from 3.63 to 6.05 kg. An increases in cooking temperatures and times decreased moisture content from 60.58 to 56.34 % and 75.14 to 47.40 % and protein content from 83.77 to 82.11 % and 89.17 to 79.45 %. Similarly, increases in cooking temperatures and times significantly (p < 0.05) increased fat content from 7.00 to 8.44 % and 4.26 to 10.12 %, ash content from 2.15 % to 2.59 % and 1.95 to 2.67 %. This study showed that increases in cooking temperatures decreased non-significantly (p > 0.05) carbohydrate content from 7.02 to 6.92 %, but increases in cooking times increased carbohydrate content from 4.63 to 7.76 %. An increases in cooking temperatures and times increased cohesiveness content from 0.50 to 0.54 and 0.40 to 0.63, chewiness value from 5.50 to 6.77 kg and 3.63 to 8.54 kg, respectively. There were no significant differences (p > 0.05) in chewiness values of samples cooked by AF and GR methods. The best cooking method/ temperature / time for low nutrient losses was BK, 170oC and 4 min

Estimación de la prevalencia de Salmonella spp. en pechugas de pollo para consumo humano provenientes de cuatro localidades de Bogotá- Colombia / Prevalence of Salmonella spp. in chicken breasts for human consumption in four districts in Bogotá - Colombia

Objetivo: Determinar la prevalencia de Salmonella spp. en muestras de pechugas de pollo para consumo humano en diferentes localidades de Bogotá. Materiales y métodos: Se obtuvieron 72 muestras en tiendas y plazas de mercado de 4 localidades de la ciudad. Las muestras fueron procesadas por métodos microbiológicos y moleculares estandarizados para la detección e identificación de Salmonella spp. Resultados: La prevalencia estimada para Salmonella spp. fue del 29.2% (n=21), de las cuales el 52.4% (n=11) fueron obtenidas a partir de muestras de tiendas y el 47.6% (n=10) de las muestras de plazas de mercado. Los serovares identificados con mayor frecuencia fueron Salmonella enterica group IIIb, S. Bredeney y S. Virchow. Las localidades con mayor presencia del patógeno fueron Usaquén y Fontibón. Discusión: Estudios realizados en Colombia reportan una prevalencia del 27% para Salmonella spp. en muestras de carcasas completas, lo que coincide con lo observado en este estudio, esto podría asociarse con inadecuadas condiciones de manejo y/o almacenamiento del producto. Conclusión: Se determinó la presencia de Salmonella spp. en las muestras de pechugas de pollo evaluadas, lo que implica un riesgo potencial para la salud pública, por lo que es necesario ampliar este tipo de estudios para conocer la situación real a nivel nacional frente a este patógeno.

Objective: To determine the prevalence of Salmonella spp. in chicken breasts for human consumption in four different districs in Bogotá. Materials and Methods: Seventy two samples were collected from different convinience stores and market places in the city. All the samples were processed using standarized microbiological and molecular methods to isolate and identify Salmonella spp. Results: The determined prevalence of Salmonella spp. was 29.2% (n=21), out of vwhich 52.4% (n=11) were obtained from convinience stores and 47.6% (n=10) from market places. The identified serovars were Salmonella enterica group IIIb, S. Bredeney and S. Virchow. The districs with highest prevalence of the pathogen were Usaqén and Fontibón Discussion: Previous studies done in Colombia have reported prevalence of Salmonella spp. around 27% in chicken carcasses, this is very similar to the prevalence observed in this study; these findings could be due to inadequate handling and storage practices of the product. Conclusion: The presence of Salmonella spp. was determined in the studied samples; this finding indicates the potential public health risk. These results demand further studies in countrywide base to determine the actual situation of this pathogen.

Influence of cutting room temperature on the microbiological quality of chicken breast meat / Influência da temperatura da sala de cortes sobre a qualidade microbiológica da carne de peito de frango

The temperature control in the processing room is one of the major factors associated with the production of safe food with a satisfactory microbiological quality. A total of 288 samples of skinless chicken breast meat were placed in a cutting room, subjected to four different temperatures (12ºC, 14ºC, 16ºC and 18ºC) and collected to evaluate the influence of the room temperature on the microbiological quality during the cutting and boning of chicken breasts. Aerobic mesophilic microorganisms were counted to evaluate the environmental contamination. In addition, coliforms at 35ºC and 45ºC and Staphylococcus spp. were counted, and an analysis for the presence of staphylococcal enterotoxins and Salmonella spp. was performed to determine the microbiological quality of the meat. The results showed an increase in environmental contamination (P=0.01) with an increase in room temperature. However, no significant differences (P˃0.05) were observed in the meat cuts regarding the counts of coliforms at 35ºC and 45ºC, the count of Staphylococcus spp. and the presence of Salmonella spp. Moreover, no staphylococcal enterotoxins were detected in the samples analyzed. Thus, despite increasing the environmental contamination, the increase in the cutting room temperature did not affect the microbiological quality of the final product.(AU)

O controle da temperatura do ambiente de processamento é um dos principais fatores relacionados à produção de alimentos seguros e com qualidade microbiológica. Com o objetivo de avaliar a influência da temperatura ambiente durante o corte e a desossa da carne de frangos sobre a qualidade microbiológica dos produtos finais, foram coletadas 288 amostras de carne de peito de frango sem pele, obtidas em uma sala de cortes climatizada submetida a quatro diferentes temperaturas ambientes (12ºC, 14ºC, 16ºC e 18ºC). Para avaliação da contaminação ambiental, foi realizada a contagem de microrganismos mesófilos aeróbios e, para a avaliação da qualidade microbiológica da carne, foram realizadas a contagem de coliformes totais e termotolerantes, a contagem de Staphylococcus spp., a pesquisa de enterotoxinas estafilocócicas e a pesquisa de Salmonella spp. Os resultados encontrados demonstraram um aumento da contaminação ambiental (P=0,01) à medida que a temperatura da sala foi aumentada. Porém, nos cortes cárneos, não foram observadas diferenças significativas (P˃0,05) na contagem de coliformes totais e termotolerantes, na contagem de Staphylococcus spp. e na pesquisa de Salmonella spp. Também não foi detectada a presença de enterotoxinas estafilocócicas nas amostras analisadas. Foi concluído que, apesar da elevação da contaminação ambiental, o aumento da temperatura ambiente da sala de cortes não comprometeu a qualidade microbiológica do produto final.(AU)

Avaliação do teor de umidade, proteína e relação umidade/proteína em cortes de frango congelados / Evaluation of the protein and relative humidity / protein in frozen chicken cuts

A ocorrência de fraudes por excesso de absorção de água em aves tem sido alvo de programas especiais de coibição do Ministério da Agricultora, Pecuária e Abastecimento (MAPA), desde 2000. Em 2010, o MAPA regulamentou a Instrução Normativa n° 32 (IN32), que estabelece os parâmetros para avaliação do teor total de água contida nos cortes de frango resfriados e congelados. O objetivo desta pesquisa foi avaliar os níveis de umidade e proteína e a relação umidade/proteína em filés de peito, coxas com e sem pele de frango comercializados congelados nos municípios de Rio de Janeiro e de Niterói. Trabalhou-se com cinco marcas de filés de peito, quatro marcas de coxas com pele e quatro marcas de coxas sem pele. Foram efetuadas determinações de umidade, proteína e relação umidade/ proteína, comparando os teores encontrados com a IN32. A marca de peito de frango4 apresentou o teor de umidade (77,41%) superior ao preconizado pela legislação e as marcas 2 (20,45%) e 4 (19,26%) teores inferiores aos estabelecidos para proteína. Todas as marcas de coxa com e sem pele possuíam teor de umidade acima do preconizado e, com relação a proteína (matéria integral), a marca 2 com pele possuía teor (14,24%) abaixo do estabelecido e a marca 2 sem pele apresentou teor acima (19,37%). Os resultados sinalizam possível fraude por absorção de água, aumentando o lucro dos produtores em detrimento dos consumidores, que se veem lesados em seu direito, ao pagarem por um produto de qualidade inferior à pretendida.

QuEChERS-HPLC-DAD method for sulphonamides in chicken breast

The development of a QuEChERS-HPLC-DAD method using a Lichrospher 60 RP-Select B column (250 x 4.6 mm x 5 µm) at 40ºC, mobile phase constituted by phosphate buffer:acetonitrile (75:25, v/v) at a initial flow rate of 0.5 mL min-1, increased by 1.2 mL min-1 and at 265 nm is presented for simultaneous determination of sulphadiazine, sulphametoxipiridazine and sulphamethoxazole in chicken breast samples. QuEchERS is inexpensive, fast and easy, and the extraction of the analytes of the matrix was successfully employed. In addition, the method presented linearity, in the range of 25, 50, 100, 150, 175, and 200 µg kg-1, precision, selectivity and sensitivity. The intraday precision (RSD %) for QuEChERS method was between 3.6-10.8 (SDZ), 6.9-14.1 (SPZ) and 1.9-10.9 (SMX) and interday precision (RSD%) was between 1.5-9.7, 1.7-4.1 and 2.1-10.2, respectively. Results of accuracy (bias) were in the range of -8.6 to +11.9 %. Therefore, the validated method is clearly useful for the practical residue monitoring of the drugs evaluated in chicken samples, as all the values were within the acceptable criteria used for food safety. Of 6 samples analyzed, none of them showed contamination of the sulphonamides studied at detectable levels.

O desenvolvimento de um método QuEChERS-HPLC-DAD usando uma coluna Lichrospher RP-60 Select B (250 x 4,6 mm x 5 µm) a 40 ºC, fase móvel constituída por tampão de fosfato: acetonitrila (75:25, v/v) a uma vazão inicial de 0,5 mL min-1, aumentando 1,2 mL min-1 e a 265 nm é apresentado para a determinação simultânea de sulfadiazina, sulfametoxipiridazina e sulfametoxazol em amostras de peito de frango. O QuEChERS é barato, rápido e fácil, e a extração dos analitos da matriz foi empregada com sucesso. Além disso, o método apresentou linearidade, na faixa de 25, 50, 100, 150, 175 e 200 µg kg-1, precisão, seletividade e sensibilidade. A precisão intradia (RSD %) para o método QuEChERS foi entre 3,6-10,8 (SDZ), 6,9-14,1 (SPZ) e 1,9-10,9 (SMX) e a precisão interdias (RSD%) foi entre 1,5-9,7, 1,7-4,1 e 2,1-10,1, respectivamente. Resultados de exatidão (tendenciosidade) foram na faixa de -8,6 a +11,9%. Portanto, o método validado é útil para a monitorização de resíduos de medicamentos avaliados em amostras de frangos, bem como todos os valores estavam dentro dos critérios aceitáveis utilizados para a segurança dos alimentos. De seis amostras analisadas, nenhuma apresentou contaminação de sulfonamidas nos níveis detectáveis estudados.

EFFECT OF CARNOSINE CONCENTRATION IN MUSCLE AND IMPROVEMENT OF EXERCISE PERFORMANCES DUE TO LONG-TERM INTAKE OF CHICKEN BREAST EXTRACT / 体力科学

The present study examined the effect of the long-term intake of chicken breast extract (CBEX), which contains carnosine and anserine, on carnosine content in skeletal muscles of humans and on short-period exercise performance with high intensity.<BR>Before and after CBEX was orally given to 13 healthy male subjects for 30 days, pieces of their muscle (<I>M. vastus lateralis</I>) were excised and carnosine concentration in the muscle was measured. Before and after the test period, the subjects exercise performance (mean and peak power body weight) was determined by pedaling for 30 sec. On the basis of baseline concentrations of carnosine, the subjects were classified into two groups: low (n=8) and high (n=5) carnosine-baseline groups. In the former group, intake of CBEX increased carnosine concentration in the muscle (p<0.05), resulting in significant correlation between increased rate of carnosine concentration and mean power. These results suggest that exercise performance depends on carnosine concentration in the muscle, and that taking carnosine-containing foods may improve exercise performance.