Carmen Josefina Contreras Castillo

Polpa cítrica em rações para cordeiros em confinamento: características da carcaça e qualidade da carne

The objective of this trial was to determine the effects of feeding diets containing citrus pulp on carcass characteristics and meat quality of feedlot lambs. Thirty-two Santa Ines lambs were distributed in a complete randomized block design according to body weight and age at the beginning of the performance trial. Lambs were fed diets containing 90% concentrate (corn and/or citrus pulp, soybean meal and minerals) and 10% coastcross hay (Cynodon spp). Citrus pulp was added at levels 23.7, 46.1 and 68.4% in the DM, replacing corn by 33, 67 or 100%. When lambs reached 33 kg of BW, they were slaughtered to determine dressing percentage, cold carcass yield, chilling loss, backfat thickness, loin eye area, cut yields and proportion of muscle, fat and bone. In addition, water holding capacity, color, cooking loss and pH were determined. Carcass characteristics were not altered by feeding citrus pulp to the lambs. However, the total replacement of corn by citrus pulp decreased carcass fat content by 12.4%.

Mechanically separated meat of broiler breeder and white layer spent hens

There are aproximately 90 millions of hens housed in Brazil, that concluding their production cycle, become available for slaughter. The poultry industry has economical interest in the use of spent hen meat through adequate processes. This review evaluates the quality of mechanically separated spent hen meat by chemical and functional characteristics, such as proximate composition, colagen, cholesterol, bones, calcium and iron contents, fatty acid profile, pH and emulsifying capacity, and as raw material for sausage production. The mechanical separation of meat migth be a good alternative use for spent hen carcasses.

Percepção pelos consumidores brasileiros da maciez da carne classificada pela força de cisalhamento e sabor

The knowledge of consumer perception of meat tenderness and taste is essential to forecast a Brazilian quality value-based beef market. This study aimed to verify perception of tender (WBSF 4.8 kg) strip loin steak or uncharacteristic (calcium-treated/Ca-IM) and normal (non-calcium/NO-Ca) meat taste by consumers according to gender, age, education and income levels. Steaks were previously classified by shear force measurements as tender or tough. Each consumer was served a paired sample of one tender and of one tough steak, which were either Ca-IM or NO-Ca treated before tenderness classification. Three hundred and eight consumers answered a nine-point intensity (tenderness) and hedonic (taste) scales evaluation questionnaire. Among consumers, 82.2% indicated beef as first choice meat products, 75.3% had beef at least four times a week; 39.3% considered taste as the most important meat attribute and 30.2% considered tenderness; 75.8% were males; 73.6% were 21 to 55 years old; 56.7% had college education; 76.6% had monthly income higher than US

Sensory and microbiological evaluation of uncured fresh chicken sausage with reduced fat content

435,00. Tender steaks were scored highest (P < 0.01), independently of gender, age and income. However, elderly consumers gave higher scores to tender steaks in comparison to middle age consumers (P < 0.05). In the lower education level, scores given to tender and tough meat did not differ. The higher income level responders assigned lower tenderness scores within tender or tough meat (P = 0.10). Differences in taste were perceived by both genders, and by consumers in every income and education level. Males gave higher scores (dislike less) within Ca-IM steaks. Consumers in the lower education level scored taste higher (like most) within untreated samples. The elderly people could not differentiate taste between the Ca-IM and NO-Ca steaks. These are the first indications that Brazilian consumers perceive tender from tough or uncharacteristic taste of beef, but palatability is evaluated differentially depending on gender, age, education and income level.

Jejum alimentar na qualidade da carne de frangos de corte criados em sistema convencional

The purpose of this study was to evaluate the acceptability and the microbiological safety of uncured fresh chicken sausages with reduced fat content, considering the scientific evidence that correlated cancer and cardiovascular diseases to this diet. Two formulations of uncured fresh chicken sausage were processed using different concentrations of cochineal carmine pigment, rosemary extracts and synthetic antioxidants, which are used to give color, appearance and pleasant flavor to the products. Then, instrumental color (L*, a*, b*, C* and h*), microbial contamination and sensory tests (ranking and acceptance) were used to evaluate the quality of the uncured chicken sausages. The instrumental color (chroma and hue) and the sensory properties of the A and B uncured sausages were similar to the commercial cured sausage (C). However, the sensory color and appearance of samples A and B were statistically higher than those of the commercial uncured sausages D, which are prepared without the addition of nitrite or pigments. The results showed that it is possible to produce safe and high-quality uncured fresh chicken sausage with reduced fat content, using natural pigments and antioxidants.

Mortadella sausage formulations with mechanically separated layer hen meat preblended with antioxidants

This research was aimed at evaluating the effect of different feed withdrawal (FW) periods (3, 6, 9, 12, 15 and 18 hours) on the live bird weight loss, dressed and chilled carcass yield (before and after of water chilling). The attributes of chilled breast meat quality of broilers raised in the conventional system were also evaluated, such as color, water holding capacity (WHC), pH, shear force and cooking loss. In this experiment, 46-day-old Ross broilers were used. The results of this study indicated that prolonged FW periods have a significant effect (P 0.05) were observed for L*, a* and b values, WHC, pH, cooking losses and pH of the breast meat submitted to different FW periods. Pearson correlation values showed a negative (P<0.001) correlation between pH and L* value, and between L* value and WHC, which varied with FW periods.

Aceitação sensorial de reestruturados empanados elaborados com filé de peito de galinhas matrizes de corte e poedeiras comerciais

Uma das formas de utilizacao das galinhas poedeiras ao final do ciclo de postura e a obtencao de carne mecanicamente separada (MSML) para a elaboracao de embutidos. Entretanto, carnes mecanicamente separadas apresentam alta susceptibilidade a oxidacao lipidica e dos pigmentos. O uso de antioxidantes tradicionalmente utilizados na cura de carne para incorporacao previa a materia prima poderia evitar estes problemas. Assim, o objetivo deste trabalho foi avaliar a qualidade e a estabilidade de mortadelas elaboradas com MSML com adicao de eritorbato (1000 ppm) e nitrito (150 ppm), como pre-cura antes da estocagem congelada, ou durante o processamento no homogeneizador (cutter) de bacia rotativa (controle). Os embutidos foram avaliados durante 40 dias (7oC) quanto a estabilidade oxidativa dos lipidios (indice de TBARS) e da cor objetiva, assim como a estabilidade microbiologica e sensorial. A pre-cura da MSML garantiu um produto final com menor rancidez quando comparado com o controle (0,2 e 2,2 mg malonaldeido/kg, respectivamente) e melhor coloracao (valores de a* entre 7,5 e 10,5, respectivamente) ao longo de todo o tempo de estocagem. As contagens totais de microrganismos psicrotroficos nao diferiram entre os tratamentos (2 log UFC g-1). A mistura previa de nitrito (150 ppm) e eritorbato (1000 ppm) em carne mecanicamente separada que possa vir a sofrer estocagem congelada prolongada antes de ser utilizada na elaboracao de embutidos e recomendavel.

Lipidic characterization of Santa Inês lamb shoulder

In Brazil, the flock size of layer and broiler breeder hens housed in 2005 was 109 million. A similar number of hens might be spent in this period. This great number of spent hens contrasts with the absence of consumer market and the low commercial value reached by these birds. The manufacture of convenience products using spent hens meat could add value and elevate the consumption of this raw material. Thus, the purpose of this study was to develop nuggets made with spent hens (white layers and broiler breeders) meat and evaluate the consumer acceptance of these products in comparison to nuggets elaborated with broiler meat. Sensory evaluation of acceptance and purchase intent was carried out in central location (400 consumers). No difference (p > 0.05) were detected by consumers in the acceptance and in the purchase intent tests between the three different nuggets evaluated. It was concluded that nuggets production could represent a good choice for the utilization of hens breast meat at the end their commercial laying cycle.

Sarcoplasmatic and myofibrillar protein changes caused by acute heat stress in broiler chicken

The edible portion of the shoulder of 12 castrated and 12 non-castrated Santa Ines lambs slaughtered at different ages (84, 168, 210, 252 days) were used. The shoulders were chemically analyzed to determine the quantity of total lipids, cholesterol, and fatty acids composition. Castrated and non-castrated lambs gained body weight (p = 0.0393, p = 0.0017) and half carcass weight (p = 0.0240, p = 0.0017), respectively. The shoulder weight was increased in the carcasses of non-castrated lambs (p = 0.0110). The edible portion of the shoulder of castrated lambs presented higher total lipids (16.09 g.100 g-1). The cholesterol content was influenced by castration (p = 0.0001) reducing with age. Castrated animals presented higher content of C18:1 T11, CLA, and C18:0. The shoulder weight is only increased with increasing age in the carcasses of non-castrated lambs. Castration influences the cholesterol content of the shoulder; however, both castrated and non-castrated lambs had their cholesterol contents reduced with increasing age. Castration and age interfered in the estearic acid concentration of the edible portion of lamb shoulder.

Molecular characterization and antibiotic resistance of Staphylococcus spp. isolated from cheese processing plants.

ABSTRACT: Acute heat stress (AHS) modifies the structure of myofibrils affecting functionalproperties of meat, mainly the water holding capacity. This experiment aimed to identify changes inproteolysis and migration between the myofibrillar and sarcoplasmatic fractions due to pre-slaughterAHS. Myofibrillar fragmentation index (MFI), SDS-PAGE, western blot of vinculin (WB) and shearforce (SF) were determined. Six hundred broilers ( Gallus gallus ) were slaughtered in three differentdays (ST). In each ST, groups of ten animals were placed in transport crates and submitted to AHS(35oC, 75 - 85% RH) for 2 hours. Simultaneously, the non-stressed broilers (NS) were kept in thermoneutralenvironment (22oC, 83 ± 6.6% RH) within the crates in the same density. After slaughter, the breastmuscles were kept refrigerated until the withdrawal of all samples (0, 1, 2, 6 and 24 hours after slaughter).Sampling within AHS and NS birds was collected according to lightness value (normal L*≤ 49, andhigh ≥ 51), except for determination of MFI and SF. The lightness was used later to perform SDS-PAGEand WB analyses. MFI kinetics showed that the fragmentation rate was superior in animals NS,indicating that AHS can harm proteolysis and rate of myofibrillar fragmentation. However, the extentof fragmentation did not change, as well as SF values. SDS-PAGE for Troponin fragments indicated adifferentiated pattern between AHS and NS. The WB did not show alterations in vinculin fragmentation.Modifications in sarcoplasmatic fraction are observed in meat with high L*values, independent ofenvironmental condition.Key words: broiler, heat stress, lightness, fragmentation index, shear force