例1某人平时下班总是按预定时间到达某处,然 然后他妻子开车接他回家。有一天,他比平时提早 了三十分钟到达该处,于是此人就沿着妻子来接他 的方向步行回去并在冷 这一天,他 比平时提前了十显然是由于节省了从相遇点到 会合点,又从会合点返回相遇点这一了多长时 间 段路的缘故,故由相遇点到会合点需 开5分钟。而此人提前了三十分钟到 请思考一下,本题解答中隐含了哪些假设?

As the first food of infant mammals, milk provides an important source of fat, protein, carbohydrate, vitamins and minerals, essential to the development of tissue and bone, and the growth of young. Milk is also a substance used beneficially by humans of all ages, both as a food in its own right and as a material for the production of milk products and milk-based food ingredients

Chilled foods are foods which are cooled to a temperature above their freezing point and which need to be maintained at that temperature to preserve quality Generally such foods will lose value if frozen, and in many cases freezing will destroy them. From the refrigeration viewpoint, the range of foods regarded as chilled is very wide. In this chapter they are taken to include fresh fruits and vegetables, both temperate and tropical in origin, the whole range of meat, fish

During recent years there has been a greatly increased consumer demand for perishable chilled foods which are perceived as being fresh, healthy and convenient. The major food retailers have satisfied this consumer demand by providing an ever increasing range of value-added chilled food products. The wide diversity of chilled foods available is accompanied by a huge range of packaging materials and formats which are used to present attractively packaged foods in retail chill cabinets. This chapter overviews the requirements and types of packaging materials and formats which are commonly utilised for a broad

The detection and enumeration of microorganisms either in foods or on food contact surfaces forms an integral part of any quality control or quality assurance plan. Microbiological tests done on foods can be divided into two types:(a) quantitative or enumerative, in which a group of microorganisms in the sample are counted and the result is expressed as the number of the organisms present

All food products are susceptible to deterioration in their quality during storage. Chilled foods in particular are highly perishable and the time during which the quality is maintained at a consumer acceptable standard can be termed the shelf-

Quality is an essential feature that will lead the consumer to select or not any food product. With numerous food scares that have hit the food market in the UK and Europe (E. coli, BSE, genetically modified organisms-based products, dioxins in animal feed in Belgium)consumers have become much more aware

Chapter13 has outlined the concept of hygienic design'and hygienic practices'in controlling the safety of chilled food products. This chapter deals with hygienic practices, specifically those related to cleaning and disinfection. Contamination in food products may arise from four main sources: the constituent raw materials, surfaces

This chapter focuses on the key elements of international and national regulatory controls and associated guidance on the manufacture, storage and distribution of chilled foods. European countries in membership of EU are covered only insofar as where national legislation or guidance exists in addition to general EU rules Since chilled foods are a relatively recent

Published by woodhead Publishing Limited, Abington Hall, Abington Cambridge cb1 6AH. england www.woodhead-publishing.com Published in No d South America by CRC Press LLC, 2000 Corporate Blvd, Nw Boca raton Fl USA First edition 1992. Ellis Horwood Ltd