The increased application of temperature legislation in many countries. coupled with economic requirements to maximise throughput, minimise weight loss and operate refrigeration systems in the most efficient manner, has created a very large demand for process design data on all aspects of

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

The appearance of meat at its point of sale is the most important quality attribute governing its purchase. The ratio of fat to lean and the amount of marbled fat are important appearance factors and another is the colour of the meat. The changes in colour of the muscle and blood pigments (myoglobin and haemoglobin, respectively) determine the attractiveness

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

The quality of fresh meat exposed for retail sale is initially judged on its appearance. The presence of exudate or'drip', which accumulates in the container of prepackaged meat or in trays or dishes of unwrapped meat, substantially reduces its sales appeal (Malton and James, 1983). Drip can be referred to by a number of different names including purge loss',press loss'and 'thaw loss'depending on the method of measurement and when it is measured. In general, beef tends to lose proportionately more drip than pork or lamb. Since most of the exudate comes from the cut ends of muscle fibres

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

一、学习内容 1、食品化学的概念及分类 2、食品化学的发展史 3、现代食品化学的发展方向 二、重点与难点

一、填空题 1、冰的导热系数在0℃时近似为同温度下水的导热系数的4倍,冰的热扩 散系数约为水的5倍,说明在同一环境中,冰比水能更快的改变自身的温度。水 和冰的导热系数和热扩散系数上较大的差异,就导致了在相同温度下组织材料冻 结的速度比解冻的速度快。 2、一般的食物在冻结后解冻往往有大量的汁液流出,其主要原因是冻结后 冰的体积比相同质量的水的体积增大9%,因而破坏了组织结构

一、概述 食品中的有毒成分主要来源于以下几个方面(1)食品中天然存在的毒素,如苦杏仁中 的氰化物;(2)食品中生物污染的毒素,如黄曲霉毒素;(3)食品中化学污染的毒素,如重 金属等;(4)食品加工过程中形成的毒素,如赖丙氨酸等

一、概述 1、食品添加剂 食品添加剂指在食品生产、加工、抱擦背感等过程中,为改善食品质地及其色、香、味, 改善食品结构,防止食品氧化、腐败变质和为加工需要而假如食品的一类物质