The origins of dehydration go back into. The preservation of food by drying has been an art for centuries but it is only in the middle of the present century that the art has been translated into terms of technology. The old methods of utilising the sun and wind to evaporate water

Preparation plant for dehydration is very to that used by the canner and freezer, because up to the last stage of conservation the raw material is prepared in similar manner, other than to provide for the introduction of certain additives which are not common to either canned or frozen products

Potato granules are more usually commercially designated as Instant Potato or Potato Mash Powder. This product was first manufactured in the UK, on commercial scale, some 55 years ago. As the name implies, precooked potatoes are dehydrated into granular form and, when hot water is added, they revert almost instantly to cooked mashed potato. This product has been widely developed as a convenience food in America and Europe

The United States is by far the largest producer of dried fruits, raisins and prunes being the most important tonnage-wise, with figs, apples, apricots, peaches and pears following in order of tonnage produced Other countries with a substantial export trade in dried fruits are Greece(producing 90 percent of the world's currant supply), Iran, Turkey, Portugal,raq, Algeria, Australia, Argentina, Egyptand South Africa. Ofthe above, the Middle East countries are particularly in the drying of figs and dates

The dehydration of meat and poultry in granule form for soup ingredients is dealt with in this chapter, as being of more practical importance than the drying of meat in larger cuts, such as slabs, dice, etc which can only be dehydrated by the AFD method. Outlets for the latter products are relatively limited in Europe, whereas there is market for soup-making- materials. Meat granules and powders can be air dried or freeze-vacuum dried

The size grading of dehydrates is an important function, both in the interests of quality and presentation, and also for the purpose of obtaining the optimum return on products undersize, or less than the standard cut. With almost all cut vegetables and fruits, there will be off-cuts from the dicers or cutters, which can be effectively separated from the primary product by the use of effective sieving machines

The food manufacturing industry, in general, has always been a highly competitive business but no branch of it is more so than dehydration. Profitability hinges on so many factors, some of which are outside the manufacturer's control. One of the main hazards in this context is that of climate. Total solids in raw materials are the key to a viable operation, and, if these are low, due to wet growing conditions, the plant throughput is going to be seriously reduced

beetroot, 125 additives and process chemicals, 52 blanch air lift dryers, 83 dicing, 126 air separation, 228 apples, 170 peeling, 126 dryers, 174 ratio, 126 preparation, 172 sizing and selection, 126 ratio, 174

第一章 绪论 第二章 食品的热处理与杀菌 第三章 食品的低温处理与保藏 第四章 食品的脱水加工 第五章 食品辐射保藏 第六章 食品的腌渍烟熏和发酵处理 第七章 食品的化学保藏 第八章 典型食品的加工工艺

由于食品和食品服务业中产生的废弃物含有大量碳水化合物 蛋白质 脂肪和无机 盐 因此废弃物成为食品行业中的难题之一 例如 如果不能合理处理乳品厂 食品冷 冻厂 食品脱水厂 肉禽制品和海洋食品加工企业的废弃物 将产生异味 并造成严重 污染 因此 在废弃物进入下水道前 必须对其中的有机物质进行生物稳定化处理 不 恰当的废水处理将给人类和水栖生物带来危害 联邦政府 地方管理部门以及公众要求各企业更好地处理废弃物的呼吁日益增加 加工企业和管理机构应该承担起及时处理废弃物的职责