| 摘要: |
| 【目的】分析不同月龄早胜牛的肉品质和加工性能，为充分挖掘早胜牛的肉用潜质提供参考。【方法】利用国标方法检测6，12，18和24月龄早胜牛背最长肌，测定其常规养分（粗蛋白、粗脂肪、灰分、水分含量）、氨基酸组分、肉色（亮度L*、红度a*、黄度b*）、pH值、剪切力（鲜肉剪切力及排酸24 h后剪切力）及蒸煮损失、滴水损失率和系水率等指标，对不同月龄早胜牛肉品质和加工性能进行评价。【结果】随着月龄增加，早胜牛肉的剪切力、系水率显著增加，滴水损失显著减小（P<0.05），其中6月龄牛肉剪切力和系水率均最小，滴水损失率最大；24月龄牛肉剪切力和系水率最大，而滴水损失率最小。随月龄的增加，肉色亮度显著下降，而红度显著上升（P<0.05）。18和24月龄早胜牛肉的pH值显著低于6和12月龄（P<0.05）；18和24月龄牛肉蒸煮损失显著低于6和12月龄，且以24月龄最小；随月龄的增加，早胜牛鲜肉剪切力显著增加（P<0.05）。24月龄牛肉粗脂肪含量显著高于其他各组（P<0.05），而6月龄显著低于其他各组（P<0.05），12与18月龄间无显著差异（P>0.05）；水分含量与粗脂肪含量的变化趋势正好相反；12与24月龄牛肉中的灰分含量无显著差异（P>0.05），但均显著高于6和18月龄（P<0.05）。各月龄牛肉中的氨基酸、必需氨基酸、非必需氨基酸总含量均无显著差异（P>0.05）；鲜味氨基酸含量以18月龄最高，显著高于6月龄（P<0.05），而与12和24月龄之间无显著差异（P>0.05）。6月龄牛肉的必需氨基酸占总氨基酸的比例、必需氨基酸与非必需氨基酸比例最高，分别为38.33%和62.00%，均显著高于18和24月龄（P<0.05），但与12月龄之间无显著差异（P>0.05）。【结论】6月龄早胜牛肉最嫩，12月龄早胜牛肉营养价值最高，而24月龄早胜牛肉能获得较高得率的加工熟肉产品。 |
| 关键词: 早胜牛 牛肉品质 氨基酸组分 牛月龄 |
| DOI： |
| 分类号: |
| 基金项目:青海省科学技术厅项目（2019-XYCX-3,2019-SF-A3,2020-ZJ-947Q）;牧科院基本科研业务费自主选题项目(MKY-2019-05);青海省“高端创新人才千人计划”（引进拔尖人才）项目 |
|
| Comparison of meat quality of Zaosheng cattle in different developmental stages |
|
WU Sen,SUN Yonggang
|
| Abstract: |
| 【Objective】This study analyzed beef quality and processing performance of Zaosheng cattle to provide reference for fully exploiting meat potential of Zaosheng cattle.【Method】This study used national standard methods to determine conventional nutrients (crude protein,crude fat,moisture and ash),amino acid composition, flesh color (L*,a* and b* color space),pH value,shear force (fresh meat and after 24 hours),cooking loss,drop loss and water-holding of longissimus dorsi of Zaosheng cattle at the age of 6,12,18,and 24 months,respectively.【Result】With the increase of age,shear force and water-holding of Zaosheng beef increased significantly,while drop loss decreased significantly (P<0.05).At the age of 6 months,shear force and water holding of Zaosheng beef were the lowest,while drop loss was the highest.At the age of 24 months,shear force and water-holding were the highest,while drop loss was the lowest.The brightness of flesh color decreased significantly with the increase of age,while the redness increased significantly (P<0.05).The pH value of Zaosheng beef at the age of 18 and 24 months was significantly lower than that at 6 and 12 months (P<0.05).The cooking loss of Zaosheng beef at the age of 18 and 24 months was significantly lower than that at 6 and 12 months.The lowest cooking loss was at the age of 24 months.Shear force of fresh meat was significantly increased with the increase of age (P<0.05).The crude fat content of Zaosheng beef at the age of 24 months was significantly higher than other groups (P<0.05),while that of 6 months was significantly lower than other groups (P<0.05).There was no significant difference between 12 and 18 months (P>0.05).The moisture content had opposite trend in comparison with crude fat content.There was no significant difference in ash content between 12 and 24 months (P>0.05),but they were significantly higher than that of 6 and 18 months (P<0.05).There was no significant difference in total amino acid content,essential amino acid content or non-essential amino acid content in Zaosheng beef among different ages (P>0.05). The content of flavor amino acid at the age of 18 months was the highest,and it was significantly higher than that of 6 months (P<0.05),but not significantly different from that of 12 and 24 months (P>0.05).The proportion of essential amino acids in total amino acids and proportion of essential amino acids and non essential amino acids were the highest of 38.33% and 62.00% at the age of 6 months.They were significantly higher than that of 18 and 24 months (P<0.05),but without significant difference from the group of 12 months (P>0.05).【Conclusion】The Zaosheng beef at the age of 6 months was the most tender,that at the age of 12 months had the highest nutritional value,while that at the age of 24 months had the highest yield of processed meat products. |
| Key words: Zaosheng cattle meat quality of beef amino acid monthly age of cattle |
