首页
登录
职称英语
Centuries ago, man discovered that removing moisture from food helps to pres
Centuries ago, man discovered that removing moisture from food helps to pres
游客
2023-10-19
10
管理
问题
Centuries ago, man discovered that removing moisture from food helps to preserve it, and that the easiest way to do this is to expose the food to sun and wind.
Fruit is sun-dried in Asia Minor, Greece, Spain and other Mediterranean countries, and also in California, South Africa and Australia. The methods used vary, but in general, the fruit is spread out on trays in drying yards in the hot sun. In order to prevent darkening, pears, peaches and apricots are exposed to the fumes of burning sulphur before drying. Plums for making prunes, and certain varieties of grapes for making raisins and currants, are dipped in an alkaline solution in order to crack the skins the fruit slightly and remove their wax coating, so increasing the rate of drying.
Nowadays most foods are dried mechanically. The conventional method of such dehydration is to put food in chambers through which hot hair is blown at temperatures of about 110℃ at entry to about 43℃ at exit. This is the usual method for drying such things as vegetables, minced meat, and fish.
Liquids Such as milk, coffee, tea, soups and eggs may be dried by pouring them over a heated horizontal steel cylinder or by spraying them into a chamber through which a current of hot air passes. In the first case, the dried material is scraped off the roller as a thin film which is then broken up into small, though still relatively coarse flakes. In the second process it falls to the bottom of the chamber as a fine powder. Where recognizable pieces of meat and vegetables are required, as in soup, the ingredients are dried separately and then mixed.
Dried foods take up less room and weigh less than the same food packed in cans or frozen, and they do not need to be stored in special conditions. For these reasons they are invaluable to climbers, explorers and soldiers in battle, who have little storage space. They are also popular with housewives because it takes so little time to cook them. Usually it is just a case of replacing the dried-out moisture with boiling water. [br] Why are sulphur fumes used before drying some fruits?
选项
答案
To preserve their colors (To prevent darkening)
解析
转载请注明原文地址:https://www.tihaiku.com/zcyy/3111616.html
相关试题推荐
AnewstudyfromtheUniversityofNewSouthWaleshasdiscoveredthatdurin
AnewstudyfromtheUniversityofNewSouthWaleshasdiscoveredthatdurin
AnewstudyfromtheUniversityofNewSouthWaleshasdiscoveredthatdurin
AnewstudyfromtheUniversityofNewSouthWaleshasdiscoveredthatdurin
AnewstudyfromtheUniversityofNewSouthWaleshasdiscoveredthatdurin
Thedaisy-likeflowersofchamomilehavebeenusedforcenturiesto________anx
Manhasusedmetalsforcenturiesingraduallyincreasingquantities,butitwas
(1)Itseemedtohim,bytheendoftheweek,thathehadlivedcenturies,s
【B1】______Whentheydryup,theyleaveuglyscarsontheskin.Forcenturies
【B1】______Whentheydryup,theyleaveuglyscarsontheskin.Forcenturies
随机试题
Manystudentsagreedtocome,butsomestudentsagainstbecausetheysaidtheyd
我读过一本译著中的一番话:科学成就了一些伟大的改变,但却没能改变人生的基本事实。人类未能征服自然,只不过服从了自然,避免了一些可避免的困难,但没能除绝祸
要使得二次型为正定的,则t的取值条件是:A.-1 B.-1 C.t>0
除新生儿外,以下哪项脑脊液检查是不正常的()A.糖定量为2.2~4.4m
概算指标以( )为确定各种消耗量指标的对象。A.单项扩大分项工程 B.单位扩
肾毒性较强的β-内酰胺类抗生素是A.青霉素G B.苯唑西林 C.阿莫西林
幼儿园家庭教育指导中教师要帮助家长认识到家庭教育是国民教育的重要组成部分,这是幼
某企业全年的销售收入是3000万元,经营成本占全部销售收入的40%,应收账款年周
于后张法预应力(有粘结)施工的说法,正确的是()。A.对于平卧重叠构件张拉
目前,国际上从立法角度认可安乐死的国家是A.澳大利亚 B.美国 C.荷兰
最新回复
(
0
)