Maria Cristina Bressan

EFEITO DO PESO AO ABATE DE CORDEIROS SANTA INÊS E BERGAMÁCIA SOBRE AS CARACTERÍSTICAS FÍSICO-QUÍMICAS DA CARNE

Thirty-six whole male lambs were used, being twenty-four of Santa Ines breed and twelve of Bergamacia breed, which weighed 15kg at the very beginning of the experiment, and were randomized allocated into slaughtering weight groups (SWG) of 15, 25, 35 and 45kg. The objective of this work was to evaluate the pH post-mortem decline, color (CIEL* a* b*), cooking weight loss (CWL) and shearing force (SF) in the longissimus dorsi (LD) and semimembranosus (SM) muscles. The examined parameters were submitted to a regression analysis. The value of pH for both muscles was expressed by regression equation of exponential type, presenting a fast fall in the first hours, followed by stabilization. The LD muscle glycolisis rate was found to develop more quickly with an increase in weight. The analysis for color components for both examined muscles presented the same behavior. The breed Bergamacia presented larger index lightness (L*), that is to say, larger brilliance. The value of L* decreased, the red content (a*) increased and the yellow content (b*) linearly decreased as the weight increased. The general analysis for color components had indicated that lamb becomes darker with weight increase. The results of CWL and SF analyses were similar in both breeds and SWG, the values for CWL were 28.0±2.5% (LD) and 30.5±4.1% (SM) and for SF 2.6±0.6kg (LD) and 2.8±0.7kg.

Qualidade da carne de cordeiros Santa Inês puros e mestiços com Texel abatidos com diferentes pesos

ABSTRACT - The objective of this study was analyze the colour, pH, weight loss by cooking (PPC) and shear force (FC) of the Longissimus dorsi (LD) and semimembranosus (SM) muscles of Santa Ines (SI x SI) and Texel x Santa Ines (T x SI) lambs, slaughteredat different live weights. Thirteen males and fourteen females were slaughtered at 15, 25, 35 and 45 of live weight. The carcasses werekept during twenty-four hours at 2 o C and during that time the pH was measured. A completely randomized design in a latin square (2x2x4)arrange for analyse of colour, PPC and FC was used. Split plot arranged was used for the pH values analysis. The decrease of pH ofboth muscles (LD and SM) was greater in the lighter animals. T x SI females meat showed higher pH values than SI x SI males lambs.The lightness values increased and darkness was lower when the slaughter weight increased. The muscles (LD and SM) of the SI x SImales were reader and darker. The PPC was lower in the heaviest animals and in the LD muscle it was lower in the female lambs. Malelambs muscles lost more water were harder than of the females muscles. The decrease of the FC was related to the increase in theslaughtering weight, and this effect was higher in the LD muscle of T x SI animals and in the SM muscle of the SI x SI animals.Key Words: ovine, muscle, colour, lightness, cooking, tenderness, pH

Physicochemical parameters and fatty acid profiles in Angus and Nellore cattle finished on pasture.

This work was carried out to evaluate the characteristics of meat quality, centesimal composition and lipid compounds (cholesterol and fatty acids) of longissimus thoracis muscle in Angus (n=30) and Nelore (n=30) bulls, at 36 months of age and 250 kg of carcass weight, finished in pasture. The results for pH, lightness, redness, cooking loss were similar among genetic groups. However, samples of Angus showed higher yellowness (4.87 and 4.04) and lower Warner-Bratzler shear force (7.86 and 9.13 kg) than samples of Nelore. Centesimal composition was similar among groups. Cholesterol was higher in Angus than in Nelore (45.45 and 39.99 mg/100g). The fatty acids C14:0, C14:1 cis 9, C18:1 trans, C18:2n-6, C18:3n-3, C18:2 cis 9, trans 11 (CLA), total of n-3 and total of polyunsaturated fatty acids were higher in Nelore than in Angus. However, the total for saturated and monounsaturated fatty acids were similar among groups. The ratio n-6/n-3 was lower in Nelore (1.58) than in Angus (1.88). Genetic groups of bovines finished on pastures affect Warner-Bratzler shear force, cholesterol and fatty acids profile. In fatty acids, this effect is more pronounced in polyunsaturated C18:1 trans, C18:2 cis 9, trans 11 and C18: 3n-3, suggesting that the Angus and Nelore breeds might differ in the metabolism of biohydrogenation. Thus, for animals finished in pasture, meat from Nelore is more nutritious than from Angus, even though it is not as tender as the one from Angus because it shows smaller percentage of cholesterol and higher levels of n-3 fatty acids, CLA and CLA precursor (C18:1 trans).

Efeitos do grupo genético, sexo e peso ao abate sobre as propriedades físico-químicas da carne de cordeiros em crescimento

O objetivo desse trabalho foi avaliar a evolucao do pH post mortem, cor, perda de peso por cozimento e forca de cisalhamento dos musculos Longissimus dorsi (LD) e Semimembranosus (SM) de 49 cordeiros provenientes de cruzamentos entre as racas Bergamacia com Santa Ines (BgxSI) e Ile de France com Santa Ines (IFxSI), machos inteiros e femeas, distribuidos nos grupos pesos ao abate de 15, 25, 35 e 45kg. Os grupos geneticos apresentaram diferencas (P<0,05) sobre o pH dos musculos LD e SM, sendo que BgxSI apresentou media de pH mais elevada, do que IFxSI. O fator sexo nao afetou a cor, entretanto o grupo genetico influenciou (P<0,001) o valor L* e o valor a*; o valor L* de 35,25 e 32,89, para IFxSI e BgxSI, respectivamente; e o valor a* de 16,09 e 14,64, para BgxSI e IFxSI, respectivamente. A perda de peso por cozimento nao foi influenciada pelos fatores grupos geneticos, sexos e grupos de peso. A maciez no musculo SM nao foi afetada pelos fatores estudados. Entretanto no LD, os grupos de peso afetaram a maciez (P<0,05). Os grupos de 15 e 25kg apresentaram forca de cisalhamento mais elevada (13,57 e 10,98kgf, respectivamente), do que os cordeiros de 35 e 45kg (8,56 e 7,97kgf, respectivamente).

Proximate composition and meat quality of broilers reared under different production systems

In this study, the physical-chemical characteristics and proximate composition of the meat of of two strains of broilers (Paraiso Pedres and Master gris plume - Super Pesadao, utilized for semi-intensive rearing) and Cobb® strain, utilized in intensive rearing systems) were evaluated. Differences related to strain and sex (males and females) were studied. Cobb® broilers were slaughtered at 45 days and the other strains at 85 days. The following characteristics were evaluated in breast and thigh meat: moisture, protein, ether extract, ashes, color (CIEL*a*b*), final pH, cooking loss (CL) and shear force (SF). Bird strain and sex influenced breast color parameters, with Cobb® presenting higher yellowness (b*) and redness (a*) means, whereas females had higher b* values and males, a* values. Paraiso Pedres had lower SF values. As to proximate composition, there was an interaction between strain and sex, with higher ether extract values in the meat of Super Pesadao males. Cobb® birds presented higher lightness (L*) and b* values, and there was no effect of sex on color parameters. Higher pH and SF values were found in the meat of Super Pesadao birds. There was an interaction between strain and sex for b* and SF values, with higher b* values obtained with Cobb® males, while differences between sex, with superiority for females in the Paraiso Pedres strain and for males in the Cobb® strain were found. Increased values of SF for males were obtained for Super Pesadao strain. Both Paraiso Pedres and Super Pesadao strains presented physicochemical and proximate composition characteristics similar to those of Cobb® strain in the cuts breast and thigh so that in a few parameters, no differences between the birds kept in this two rearing systems were found.

Efeito de métodos de cocção sobre a composição química e colesterol em peito e coxa de frangos de corte

Neste experimento, objetivou-se comparar os efeitos dos metodos de coccao: cozimento em agua (CA); em oleo (FO); em grelha (GR); em forno convencional (FC) e em forno de microondas (MO), sobre a perda no cozimento (PPC), composicao centesimal (CC), taxas de retencao aparente, taxa de retencao verdadeira da gordura e colesterol dos cortes peito e coxa de frangos. O delineamento experimental foi o inteiramente casualizado, com 5 tratamentos e 5 repeticoes, totalizando 25 parcelas experimentais. Os metodos de coccao influenciaram (P<0,05) a PPC, de forma que files assados no forno de microondas mostraram perdas de 32,49%, maior do que as perdas nos metodos CA, FC, FO e GL (28,40; 27,04; 29,18; e 23,46%, respectivamente). O tratamento FO apresentou, na materia natural, valores mais elevados de gordura no peito (2,49%) e coxa (7,85%), quando comparado aos tratamentos CA, FC, FO, GR, MO (peito, com medias de 1,06 a 1,35 e coxa com medias de 5,06 a 6,27). Os valores de cinzas, na materia seca, demonstraram perda de minerais durante a coccao. Os metodos de coccao sem oleo ocasionam perdas de lipideos das amostras, enquanto os cortes submetidos a fritura absorvem oleo. O corte peito absorve mais gordura do que o corte coxa.

Composição proximal e qualidade da carne de frangos das linhagens Paraíso Pedrês e Pescoço Pelado

Neste trabalho foram avaliadas as caracteristicas fisico-quimicas da carne de frangos de duas linhagens (Paraiso Pedres e Pescoco Pelado) criados em sistema semiextensivo, machos e femeas, abatidos aos 65, 75, 85 e 95 dias. As caracteristicas analisadas nos cortes peito e coxa foram umidade, proteina, extrato etereo, cinzas, cor (CIEL*a*b*), pH final e perda de peso por coccao. As femeas da linhagem Paraiso Pedres apresentaram no peito mais gordura (0,86%) em comparacao aos machos das linhagens Paraiso Pedres (0,63%) e Pescoco Pelado (0,57%). A coxa das aves da linhagem Pescoco Pelado aos 85 dias apresentou maior umidade e menor porcentagem de gordura em comparacao a linhagem Paraiso Pedres, e aos 95 dias, as femeas Paraiso Pedres apresentaram mais gordura que os machos. A cor amarela (b*) no peito foi mais intensa nas aves Pescoco Pelado (6,24) que nas aves Paraiso Pedres (5,41). Tambem foi mais intensa nas femeas (6,47) que nos machos (5,18). A cor da coxa nas aves Pescoco Pelado foi mais amarelada aos 95 dias (6,87) que aos 85 dias (5,90). Aves da linhagem Pescoco Pelado podem fornecer cortes mais magros, no caso dos machos, e com coloracao mais amarelada, no caso das femeas, que aves da linhagem Pescoco Pelado.

Ácidos graxos na carne de búfalos e bovinos castrados e inteiros

The objective of this experiment was to compare fat and cholesterol content, and fatty acids (FA) profile in Longissimus dorsi muscle of castrated and young bulls from Nellore (NE) and ½ Nellore x Sindi (NS) cattle and Mediterranean buffaloes. Eight animals (four castrated and four young bulls) per genetic group was used, with a total of 24 animals. A completely randomized experimental design in a 3 x 2 factorial arrangement (three genetic groups and two sexual conditions) was used. Animals were fed the same diet and were slaughtered at average live weight of 437.5 kg (± 3.4 kg). Buffaloes and ½ NS beef cattle showed smaller fat percentage in meat (10.8 and 12.5%, respectively) than NE beef cattle (15.4%), as well as young bulls animals (8.9%) as compared to castrated animals (16,8%). For cholesterol and monounsaturated FA there was no difference among genetic groups and sexual conditions. For polyunsaturated FA, buffaloes showed higher content (9.55%) than beef cattle (7.27 NE and 8.95% ½ NS), as well as young bulls animals (9.96%) as compared to castrated animals (7.21%). Buffaloes and NE beef catle showed higher saturated FA content, 42.7 and 42.1%, respectively, in relation to ½ NS beef catle (39.8%). Buffaloes and young bull animal meat showed smaller fat content and higher polyunsaturated FA, showing that could be better for human healthy.

Efeitos dos métodos de abate e sexo na composição centesimal, perfil de ácidos graxos e colesterol da carne de capivaras

The objective of this work was to evaluate the effects of two slaughter methods: traditional (TS) and head-shot (HS) and sex on the proximate composition, fatty acids (FA) profile and cholesterol content of capybara meat. Twenty animals (13 males (M) and 7 females (F)), weighting about 45.71kg, were slaughtered. In longissimus dorsi (LD) muscle were determined: moisture, crude fat, protein and ash. In semimembranosus (SM) muscle, were determined: cholesterol content for colorimetric method and fatty acids (FA) profile for gas chromatography. The LD muscle had values of: 75.87% of moisture, 1.37% of crude fat, 22.11% of crude protein, 1.09% of ash. There were significant differences (p<0.01) between lipid contents of M (1.75%) and F (0.98%). The FA in major concentration (%) were: C16:0 (29.57); C18:1w9 (27.87); C18:2w6 (19.19); C18:0 (6.57); C18:3w3 (4.97); C14:0 (3.64); C20:4w6 (3.45); C18:1w7 (3.31) and C16:1w7 (1.90). Ratio value of poliunsaturated FA to saturated FA was 0.82. The average values of w6 FA and w3 FA were 23.41 and 5.63%, respectively. The factors sex and slaughter method had no effect on poliunsaturated FA percentages and cholesterol content (28.11mg/100g). Capybara meat presented low total lipid content and high crude protein values and FA w6/w3 ratio considered nutritionally adequated.

Physicochemical properties of meat from Bos taurus and Bos indicus

The objective of this study was to characterize meat quality in Bos taurus and Bos indicus and to determine the influence of finishing system and genetic group on the physicochemical properties of the longissimus thoracis at 24 hours and 10 days post mortem (1oC). The sample included 160 bulls of the B. taurus (n=75) and B. indicus (n=85) groups, finished either on pasture (n=46) or with grain supplementation (n=114), slaughtered at a carcass weight of 270 to 300 kg. Pasture-finished animals had higher pH, lower red content and a fat content 2.5 times lower than those finished with supplementation. Meat from supplement-finished animals had lower shear force in comparison to that from animals finished on pasture, with means of 7.7 and 8.5 kg at 24 hours, and of 5.5 and 5.9 kg at 10 days, respectively. Samples of B. taurus and B. indicus were similar in moisture and protein, but B. taurus presented higher means for ash and lower means for fat. Aged samples of B. indicus finished on pasture showed lower values for lightness and yellowness. Overall, lightness and yellow content increased and red content decreased with 10-day ageing. Means for shear force were lower in B. taurus than in B. indicus, with differences of 1.4 kg in fresh meat and 0.6 kg in aged samples. The reduction in shear force with ageing was more pronounced in samples with higher initial shear force, in spite of the positive relationship between shear force before and after ageing.