响应面法优化PSE猪肉低温香肠配方

通过单因素试验,考察了卡拉胶、转谷氨酰胺酶(TG酶)及大豆分离蛋白对PSE猪肉低温香肠质构特性和感官品质的影响。结果表明,单独添加卡拉胶、TG酶或大豆分离蛋白可以显著改善PSE肉低温香肠的硬度、弹性、内聚性和咀嚼性。在单因素试验的基础上,通过响应面试验优化得出PSE猪肉低温香肠的最佳改良剂添加量为:卡拉胶占总料0.5%,TG酶0.6%,大豆分离蛋白3%,按此配方制得的产品切面光滑、紧密,软硬适中,肉香浓郁,具有较高的感官评分。     

不同屠宰方式对猪肉品质的影响

选用不同致晕、放血法及烫毛方法对140头杜长大和杜大长三元杂商品猪进行屠宰,测定其肌肉的肉色、pH值、剪切力、失水率等指标。结果表明：在其他条件相同的情况下,烫毛水温为60℃时,烫毛6min,胴体质量最佳。电击致晕生猪,采用悬挂放血,有出现PSE猪肉的倾向;而CO2致晕生猪,采用水平放血或悬挂放血,肉质指标差异不显著。较好的组合是：电击致晕生猪,采用水平放血;而CO2致晕生猪,采用悬挂放血较好。     

猪应激综合征发生与控制的初步研究

猪应激综合征是在受到外界不良环境或有害因子的作用下出现的非特异性反应,主要有猪恶性高温综合征、猪急性背肌坏死、猪宰后腿肌坏死、猪自然应激综合征、水猪肉、突毙综合征等几种表现形式。通过对猪应激综合征的症状、发病原因、发病机制、病变特征以及控制措施等方面进行综述,并结合临床所见,以亟为生产实践提供参考。     

快速溶剂萃取技术在2种食药用真菌多糖提取中的应用

为建立快速溶剂萃取技术提取食药用真菌多糖的新方法,以猪苓、茯苓为研究对象,采用单因素及正交实验优选快速溶剂萃取法提取多糖的最佳工艺条件。结果表明,快速溶剂萃取法用于猪苓多糖提取的最佳工艺参数为提取温度110℃,提取压力110 bar,提取时间20 min,循环2次,在此条件下,猪苓多糖的含量为(7.8684±0.1096) mg/g。快速溶剂萃取法提取茯苓多糖的最佳工艺参数是提取温度110℃,提取压力120 bar,提取时间25 min,循环2次,在此条件下,茯苓多糖的含量为(8.6965±0.1087) mg/g。快速溶剂萃取技术能够快速、准确地适用于2种食药用真菌多糖的提取。     

Evaluation of colorimetric pH strips for wild animal meat using image analysis

Colorimetric pH strips (MColorpHast™) are very convenient to use, but the decision of pH is based on an individual's color perception and is, therefore, subjective. We developed a pH calculation program for the image of coloring strips on CIE1976 (L*a*b* color space), which slightly underestimated human judgment as the color of pH darker. This image analysis and three individuals' judgments were used for evaluating the strip's features for various qualities of meat from wild animals, and the results were compared with the assessments based on potentiometric pH. In both methods, dipping the strips in distilled water just before use improved the regression coefficient compared with that mentioned in the manual. The image analysis showed higher correlation than human judgments but slightly underestimate pH by a maximum of 0.13 unit from the regression line of the potentiometric pH. In addition, the image analysis revealed meat pigment changed pH higher on the color scale in the lower meat pH region. The strips must be used according to the manual, but dipping is effective when the meat surface is dry, and keeping the strips from touching the meat drip is important in lower pH region because the pigment affects the color of pH.     

吉林省农业支持与保护的实证分析

利用相关模型和指标对1996—2003年的吉林省农业支持与保护总体水平、边境保护情况、国内支持水平进行了定量分析。结果表明:从总体上看,吉林省农业仍处于负保护状态,并且保护水平与价格干预程度密切相关;从边境保护方面看,除玉米外,多数品种处于负保护状态,并且保护效果年际变化显著;从国内支持看,“黄箱”政策空间较大,而“绿箱”政策结构不尽合理,特别是对减少收入差距、促进社会公平的目标关注不够。     

巴西的农业支持政策及对中国的借鉴

巴西农业在其国民经济中的地位举足轻重,在全球对农业进行支持的大环境下,巴西政府对其农业的支持政策具有鲜明的特点。本文应用OECD的分析方法体系对巴西的农业支持水平进行了评估分析,指出了巴西农业政策的特点,并提出对中国的借鉴建议。     

The effects of the dark house system on growth,performance and meat quality of broiler chicken

Meat production with minimum animal suffering is a humanitarian concern. Thus, the objective of this work was to observe the performance of Cobb broiler chickens from 7 to 46 days of age when raised under different installations: dark house system (DHS), conventional yellow system (CYC) and conventional blue system (CBC). The feed conversion ratio for the birds raised on the DHS was 3.8% and 2.7% lower than those for the CYC and CBC systems, respectively. Compared with the CYC and CBC systems, average daily gain under the DHS was 11.4% and 9.3% higher, respectively, and body weight at 46 days was 11.4% and 9.3% higher, respectively (P ≤ 0.05). The birds' welfare was assessed based on their stress by determining the amount of pale, soft and exudative (PSE) meat in the breast fillets. The CYC and CBC birds had 24.3% and 25.3% PSE meat, respectively, whereas the DHS birds had 37.0%. We concluded that the DHS has a greater potential to produce broiler chickens, with superior performance to conventional systems, despite the higher stress faced by the birds during the maneuvers just before slaughter.     

猪肌肉组织中糖原酵解酶活性和PSE肉的相关性

本文用２０头猪的肌肉样品研究了肌肉纺织中丙酮酸激酶，磷酸果糖激酶，乳酸脱氢酶和ＰＳＥ肌肉的相关性。结果表明：屠宰后４５ｍｉｎ采取的肌肉中ＰＫ和ＰＦＫ活性在正常骨肉和ＰＳＥ肌肉之间差异极显著（Ｐ＜０．０１）。并且ＰＫ与常规肉质指标ｐＨ值，系水力和光反射值存在显著相关性（Ｐ＜０．０５，Ｐ＜０．０１，Ｐ＜０．０１）。