No abstract

Twenty four broilers (Ross) and 24 ducklings (Cherry berry) aged 45days were stunned and killed by conventional neck cut to evaluate the meat characteristics and fatty acid composition of breast meat. Breast meats were removed from each carcass at different post-mortem times. After complete processing, the breast meats were then placed in a polythene bag and kept in a cold storage room at 4°C for 7 days. The pH of meat samples at different post-mortem times, and meat characteristics and fatty composition at different storage times were evaluated. No significant differences were found in pH at different post-mortem times except at 30 min postmortem, where duck breast showed significantly lower pH than chicken breast. As expected, duck breast meat had significantly higher redness (a*), but lower lightness (L*) value compared to chicken breast. During whole storage time, the a* value remained constant in duck breast. Cooking loss (%) was higher in duck breast compared to chicken breast during the whole storage time. Shear force decreased with increasing storage time in both chicken and duck breast meat, moreover, it decreased rapidly in duck breast compared to chicken breast. The TBARS values increased with increasing storage time in both duck breast and chicken breast meat and was significantly higher in duck breast. The fatty acids (%) C14:0, C16:0, C16:1, C18:2 and C18:3 were significantly higher while C18:0 was significantly lower in duck breast compared to chicken. SFA was increased, while USFA and MUSFA decreased only in duck breast during the 7 day storage time.

No abstract

This study was carried out to compare the quality properties of chicken breast surimi manufactured by four different procedures/methods. Surimi was made from chicken breast by washing two (T1) or four times (T2) with water as well as by pH adjustments at 3.0 (T3) or 11.0 (T4). The contents of moisture and crude fat were significantly higher in the surimi manufactured from pH-adjusted material than after washing. Again, collagen and yield were significantly higher in chicken breast surimi manufactured from washed than pH-adjusted samples, whereas crude protein was higher in the pH-adjusted than washed surimi samples. There was no significant difference in myofibrillar protein content among the surimi manufactured after different washing times and differences following pH adjustments were found. T4 showed highest myofibrillar protein content rating among the surimi samples. All physical characteristics were higher in pH-adjusted chicken breast surimi than in T1 and T2 washed surimi samples. The pH-adjusted surimi had higher hardness, gumminess and chewiness than washed surimi samples (p<0.05). The chicken breast surimi made by pH adjustments had higher lightness (L*) than when made by washing times, whereas pH 3.0-adjusted surimi samples had lower whiteness (W) then the other surimi samples. Myoglobin content was significantly higher in the surimi manufactured from pH-adjusted chicken breast samples.

A total of 250 laying hens were fed a diet containing 0, 1, 2.5 or 5% conjugated linoleic acid (CLA), and 5% Safflower seed oil (SSO) for 5 weeks, and eggs were collected by week to analyse lipid characteristics of egg yolk. Egg yolk from CLA-fed groups showed significant increase in CLA content with increased CLA in the diet. Dietary CLA also increased the ratio of saturated fatty acids and decreased unsaturated fatty acids in the egg yolk. The proportion of myristic, palmitic, stearic and CLA were increased, while those of oleic, linoleic, linolenic and arachidonic acid were decreased. The cholesterol content in egg yolk was significantly decreased by dietary CLA for 5 weeks feeding. After 7 days of feeding, 5% CLA-fed group showed the lowest cholesterol content in egg yolk. CLAfed groups showed significantly lower 2-thiobarbituric acid-reactive substances (TBARS) values compared to control and SSO-fed group after 14 days of storage. No significant differences in TBARS values among CLA-fed groups were observed at the 28 days of storage. Results suggested that lipid oxidation of egg yolk during cold storage could be inhibited by dietary CLA due not only to changes in fatty acid composition but also to the high concentration of CLA in egg yolk.