RESUMO
Early weaning of calves (60 days old) is adopted in cow-calf operations for its high reproductive response. The objective of this research work was to find how age classes are related to beef quality in early weaning cull cows. Twenty four cows were grouped in four different age classes (teeth and number of calves produced) from two teeth and no calf produced, up to 12 years and 7 calves produced. All cows grazed a perennial pasture based on alfalfa and fescue. There were differences (P<0.05) in final weight (younger cows being lighter) but no other differences could be found during field conditions or in abattoir data (carcass weight and yield, top value hindquarter cuts weight and carcass percent). No differences (P>0.05) could be found in meat quality attributes except for moisture, protein and fat yellowness. Differences (P<0.05) in sensory attributes could only be found in connective tissue.
RESUMO
The meat quality of Corriedale lambs (40kg live weight) produced in the Mesopotamia region (Argentina) was assessed. These lambs had different finishing diets: only native grass pasture, ground alfalfa and alfalfa-linseed pellet (70/30). Carcass yield, longissimus dorsi area, backfat thickness, marbling, pH, meat and subcutaneous fat color, cooking loss, Warner-Bratzler shear force, fat, protein and moisture content were determined. Lambs finished on alfalfa-linseed pellet had the highest carcasses yield and backfat thickness and their meat had a lighter color (higher L(∗) value), higher marbling and tenderness than meat from lambs reared on native grass pasture. Grass-based finishing can lead to the production of leaner meat, with a more reddish color (higher a(∗) value). The ground alfalfa finishing diet seems to be intermediate between native grass pasture and alfalfa-linseed pellet with respect to carcass yield, backfat and meat color. In addition, the animals fed on ground alfalfa showed the highest muscle area.
RESUMO
The effects of different proportions (0%, 10%, 20%, 30%, 40%) of washed mechanically deboned chicken meat (WM) as a substitute for hand deboned chicken meat, on the physicochemical and sensory characteristics of chicken nuggets were evaluated. The addition of WM increased fat content, but it was only significant (P<0.05) when 40% of WM was added, whereas the protein content was significantly (P<0.05) reduced as from 20%. Significant differences (P<0.05) were found in L(*), a(*) and b(*) values with different proportions of WM, however, these differences were evidently not discerned as shown by the no significant differences (P>0.05) in ΔE(*) color scores. The addition of WM did not affect (P>0.05) sensory attributes of chicken nuggets. From a technical viewpoint, up to 40% WM could be incorporated into nugget formulation instead of hand deboned chicken meat without affecting sensory attributes of the product. Minor changes in composition were observed but they were probably not detrimental to the product.
RESUMO
The aim of this work was to study the influence of different conditions on the thiobarbituric acid (TBA) test, determined by the extractive method, as a measure of lipid oxidation in 'paté'. Different extracting agents (trichloroacetic acid and trichloroacetic acid in 2 M phosphoric acid), different concentrations of these acids (10, 15 and 20%), different reaction times and temperatures (35 min at 100 °C and 900 min at room temperature) and the effect of sulfanilamide additions were evaluated. All the samples were measured by HP 8451A Diode ARRAY spectrophotometer at 532 nm. Significant differences between 35 and 900 min of MA-TBA reaction time were found. Highest TBA numbers were found in samples with a reaction time of 35 min in a thermostatically controlled waterbath at 100 °C, rather than 900 min at room temperature. Lowest TBA numbers were found in samples with the addition of sulfanilamide rather than without it. The 10% TCA solution gave the best recovery percentages for 'paté', making it the preferred extractant.
RESUMO
The evolution of different physico-chemical parameters (iodine number, TBA test, residual nitrite level, pH and moisture) and CIE L (∗)a (∗)b (∗) colour evolution, in pork liver 'pate', with and without sodium ascorbate addition, were studied. The samples were stored in an illuminated display cabinet at different lux intensities and in the dark. The regression equations were obtained for each one of the parameters under study, from the first day of exposure to light. The sodium ascorbate showed a protective effect on the photo-oxidation mechanism (measured by TBA test), but it did not have an influence on the samples in darkness. In both types of paté exposed to light, fading takes place and the most important variations in colour parameters are produced during the first 24 h of exposure to light.