影响猪肉品质的主基因及其研究进展

影响猪肉品质的因素很多,但遗传基础是改善猪肉品质的关键。本文将对影响猪肉品质的两种主基因:氟烷基因(Hal)和酸肉基因(RN)的研究现状作一综述。     

Structural weakening of intramuscular connective tissue during postmortem aging of pork

We studied structural changes in the endomysium and perimysium during postmortem aging of pork using the cell‐maceration/scanning electron microscope method. Immediately post mortem, endomysia sheaths that house individual muscle fibers displayed a honeycomb‐like structure. The sheaths of the endomysium consisted of tightly arranged collagen fibrils in a random network. The perimysium comprised several layers of wavy sheets made up of tightly bundled collagen fibers. While the structure of the intramuscular connective tissues remained almost unchanged up to five days post mortem, the endomysium had resolved into individual collagen fibrils, and the thick sheets of the perimysium had separated into collagen fibers and fibrils at 8 days post mortem. These results provide direct evidence for structural weakening of the endomysium and perimysium during postmortem aging of pork. The shear‐force value of raw pork decreased rapidly within six days post mortem and then decreased slowly until 14 days post mortem. Since the rapid increase in tenderness is mainly due to structural weakening of myofibrils, we conclude that the disintegration of the endomysium and perimysium contributes to tenderization of pork during extended postmortem aging.     

兽用中成药四味穿心莲散质量标准提高研究

目的：开展四味穿心莲散的质量标准提高研究.方法：采用薄层色谱法对处方中大青叶进行定性鉴别.用高效液相色谱法对四味穿心莲散中穿心莲内酯和脱水穿心莲内酯进行含量测定,色谱条件：Diamonsil C18色谱柱（250 mm×4.6 mm,5μm）,流动相为甲醇-水,梯度洗脱,穿心莲内酯检测波长为225 nm,脱水穿心莲内酯检测波长为254 nm,流速为1.0 mL/min.结果：该薄层鉴别方法分离度良好,专属性强.穿心莲内酯的含量测定范围为0.052 6-0.526 1μg（r=0.999 3）,脱水穿心莲内酯的含量测定范围为0.051 7-0.517 3μg（r=0.999 7）.穿心莲内酯的加样回收率为99.2％,RSD为2.4％;脱水穿心莲内酯加样回收率为101.2％,RSD为1.6％.结论：该方法简便、准确、重现性好,可用于四味穿心莲散的质量控制.     

SNP discovery, expression and association analysis for the SDHD gene in pigs

The SDHD gene was examined for single nucleotide polymorphisms (SNP) as well as for expression changes in the Longissimus dorsi muscle of commercial pigs with different potential for growth. Three SNPs, including one previously described in the coding region and two new ones in the 3'-UTR, were found. The normalized expression of SDHD was correlated with growth, meat quality and sensory traits (p < 0.05). For the commercial pigs used in this study, as well as a Berkshire × Yorkshire resource population, the SNPs have been associated (p < 0.05) with: growth, carcass composition, meat quality and sensory traits. Despite the fact that the described SNPs were not significantly associated with the normalized expression values, the SDHD SNPs and expression were associated with growth and meat quality traits in pigs.     

贵州省鲜猪肉中农药残留监测分析

为了解贵州省鲜猪肉中农药残留的总体情况与来源,采用色谱分析法对贵州省9个地区农贸市场随机采集的108份鲜猪肉样本进行检测。结果表明:贵州省农贸市场销售的鲜猪肉中农药残留均无响应值,低于国家标准最低检出限,所检样本中无阳性检出,符合国家卫生标准,即未检出。贵州市场销售的鲜猪肉比较安全。     

中国猪肉安全控制系统的问题与对策

20世纪90年代中期以来,在猪肉国际贸易中,价格的作用变得越来越弱,产品质量安全是影响产品国际贸易竞争力的核心要素,并成为影响企业成败的关键因素之一.而产品质量安全取决于质量安全控制系统的设置以及运行效率.文章从法规标准系统、猪肉安全管理系统、疾病预防和控制系统及猪肉检验和保证系统4个方面分析了中国猪肉安全控制系统及其存在的不足,指出OIE无病区认可、HACCP安全管理和食品安全追溯制度是中国猪肉安全控制系统与发达国家差距的主要表现.文章进而分析了存在不足的原因,在此基础上提出了完善中国猪肉安全控制系统的对策建议.     

Seaweed Polysaccharides (Laminarin and Fucoidan) as Functional Ingredients in Pork Meat: An Evaluation of Anti-Oxidative Potential,Thermal Stability and Bioaccessibility

The anti-oxidative potential of laminarin (L), fucoidan (F) and an L/F seaweed extract was measured using the DPPH free radical scavenging assay, in 25% pork (longissimus thoracis et lumborum (LTL)) homogenates (TBARS) (3 and 6 mg/mL) and in horse heart oxymyoglobin (OxyMb) (0.1 and 1 mg/mL). The DPPH activity of fresh and cooked minced LTL containing L (100 mg/g; L₁₀₀), F₁₀₀ and L/F_100,300, and bioaccessibility post in vitro digestion (L/F₃₀₀), was assessed. Theoretical cellular uptake of antioxidant compounds was measured in a transwell Caco-2 cell model. Laminarin displayed no activity and fucoidan reduced lipid oxidation but catalysed OxyMb oxidation. Fucoidan activity was lowered by cooking while the L/F extract displayed moderate thermal stability. A decrease in DPPH antioxidant activity of 44.15% and 36.63%, after 4 and 20 h respectively, indicated theoretical uptake of L/F antioxidant compounds. Results highlight the potential use of seaweed extracts as functional ingredients in pork.     

日粮添加氧化鱼油及硒和维生素E对育肥猪生产性能的影响

试验旨在研究氧化鱼油对育肥猪后期生产性能和冷藏生猪肉肉质的影响以及硒和维生素E的抗氧化作用。将40头DLY杂交猪(59.4kg)分为4个处理,对照组和3个添加剂组(0.3mg/kg硒,100mg/kg维生素E,0.3mg/kg硒+100mg/kg维生素E)。试猪平均体重为81.3kg时,将每个处理的10头猪各分为2组,分别在日粮中添加5%新鲜和氧化鱼油,试猪于平均体重109.8kg时屠宰取样。结果表明:①各处理组血清乳酸脱氢酶(LDH)和冷藏0~6d肉样的TVB-N、pH、L*无显著差异。②氧化鱼油显著提高肌肉丙二醛(MDA)含量,肉色b*值和血清尿素氮(BUN)、丙二醛(MDA)(P0.05);③油脂和添加剂在日增重(ADG)、滴水损失、肉色a*值、血清超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GPx)活性上表现显著的互作效应(P0.05)。本试验结果表明育肥后期添加5%氧化鱼油5周,对冷藏2d肉样b*值和2、4d肉样MDA含量有显著影响,硒和维生素E表现显著的抗氧化效应和与氧化鱼油的互作效应,硒+维生素E的添加在氧化鱼油组的作用效应大于新鲜鱼油组。