Showing 3 results for Jebelli Javan
Volume 20, Issue 137 (July 2023)
Abstract
The present research aimed to evaluate the effects of roasting and microwave thermal processes along with pH change on the amount of residues of three commonly used antibiotics, enrofloxacin, oxytetracycline and sulfadiazine in chicken meat. For this purpose, first the three antibiotics were added to the chicken meat samples in amounts 4 times the remaining limit. Meat samples containing residues of each antibiotic were subjected to roasting (at 200 °C for 30 minutes) and microwave (at 100 °C for 3 minutes) treatments at pH 5.8 and 4.8. Then, the residual amount of each of the antibiotics was investigated by high-performance liquid chromatography (HPLC) along with colorimetry and evaluation of cooking loss. The results showed that both treatments were able to significantly reduce the amount of antibiotic residues, but both processes were more effective at pH 4.8 than 5.8 (P<0.05). The highest amount of reduction of antibiotic residue at pH 4.8 in both microwave and roasting treatments was observed in oxytetracycline residue with 76.2 and 72.4% respectively. Roasting and microwave treatments decreased L* index, but a* index decreased in roasting and increased in microwave, and b* index increased in microwave, but there was no significant change in roasting. Also, the amount of cooking loss in roasting in the range of 58 to 71% was more than that of microwave in the range of 48 to 62% (P<0.05). Finally, microwave treatment can be introduced along with reducing the pH of chicken meat to 4.8 as the best treatment to reduce antibiotic residues.
Volume 22, Issue 163 (September 2025)
Abstract
This study aimed to investigate the effect of adding calcium salts of unsaturated fatty acids (omega 3, 6, and 9) on the meat quality characteristics of male Sangsari lambs. In this study, 28 lambs were divided into four nutritional groups with different levels of fatty acids and received the corresponding diets for 75 days. Meat quality was evaluated using color (L*, a*, b*) indices, lipid oxidation (MDA), hardness, cooking loss, and water holding capacity. The results showed that adding omega 3 resulted in a decrease in transparency and an increase in meat yellowness, while the hardness of the texture decreased and its softness improved. Although the MDA concentration increased, these values still remained within acceptable limits. Also, unsaturated fatty acid supplements reduced cooking loss and improved water holding capacity, indicating higher stability of the meat during storage. In general, adding these supplements to lamb diets can be used as an effective strategy to improve meat quality and shelf life. However, the effects depend on the type and amount of fatty acid consumed.
Volume 22, Issue 163 (September 2025)
Abstract
L-carnitine is used as a nutritional supplement in animal nutrition to improve meat quality and reduce fat oxidation. This study was conducted on male Sangsari lambs with the aim of investigating the effect of L-carnitine on color characteristics, fat oxidation, tenderness, and meat cooking loss. The lambs were divided into three groups of control, 150, and 300 mg L-carnitine per kilogram of diet. The results showed that the addition of L-carnitine to the diet, especially at the 300 mg level, caused significant changes in meat color parameters; such that the intensity of yellowness increased and the amount of redness decreased. These changes are probably due to increased fat oxidation and changes in muscle protein composition. The group receiving 300 mg showed the highest level of brightness, which may be related to a decrease in red pigments and an increase in yellow pigments. Measurement of malondialdehyde, an indicator of fat oxidation, showed that L-carnitine significantly reduced fat oxidation, resulting in improved meat quality and shelf life. L-carnitine supplementation also temporarily tenderized the meat, but this effect decreased over time. No significant differences were observed between groups in terms of cooking loss. Overall, L-carnitine may improve meat quality, but further studies are needed to confirm the results.