From the moment an animal is slaughtered the meat produced begins to lose weight by evaporation. Under typical commercial distribution condi tions, it has been estimated that lamb and beef lose from 5.5 to 7% by evap- oration between slaughter and retail sale(Malton, 1984). Weight losses from pork are probably of the same magnitude. In addition to the direct loss in saleable meat there are also secondary

Whilst a number of characteristics affect the overall quality and acceptability of both fresh and frozen meats, tenderness is the major characteristic of eating quality because it determines the ease with which meat can be chewed and swallowed. The tenderness of meat is affected by both chilling/freezing and storage. Under the proper conditions, tenderness is well maintained throughout the chilled/frozen storage life, but improper chilling/freezing can produce severe toughening and meat of poor eating quality

Microbiology of refrigerated meat There are many pertinent texts on the microbiology of meats. The purpose of this chapter is to examine briefly the types of micro-organisms and con- ditions that are of interest in relation to the refrigeration of meat and meat products. In a perfect world, meat would be completely free of pathogenic(food poisoning

目录 实验一采精 实验二精子活率、密度、畸形率和精液PH值的测定 实验三公畜精液的稀释及低温保 实验四精液的冷冻保存 实验五活体母牛的直肠触诊及直肠握输精 实验六母牛的发情鉴定 实验七妊娠诊断 实验八兔的超数排卵和卵子、胚胎的收集

第九章工业制冰 第一节人造冰的制取分类 第二节盐水间接冷却制冰设备 第三节直接冷却制冰设备

压缩机作为主机 一类是主要设备:冷凝器、蒸发器、节流机 构等,这些是完成制冷循环必不可少的设备 另一类是辅助设备:各种贮存、分离和安全 保护等设备,这些设备的作用是改善制冷系 统的工作条件,提高系统运行的经济性和安 全可靠性

第五章流装置、阀门与辅助设备 第一节节流装置 第二节制冷系统常用阀门 第三节制冷系统常用阀门

在蒸气压缩式制冷装置中,选用 了各种类型的制冷压缩机。它们是装置 中的关键核心设备,对系统的运行性能 、噪声、振动、使用寿命和节能有着决 定性的作用

本章介绍单、双级蒸气制冷循环 的特性及热力计算方法。着重分析理 论循环,并讨论理论循环和实际循环 的差别,此外还介绍了复叠式制冷循 环的组成及其应用

第一节建筑常用动力设备及对供电要求 一、配电分布的要求 1、给排水动力负荷 2、冷冻机组动力负荷 3、电梯负荷 4、照明负荷