首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Centuries ago, man discovered that removing moisture from food helps to preserve it, and that the easiest way to do this is to e
Centuries ago, man discovered that removing moisture from food helps to preserve it, and that the easiest way to do this is to e
admin
2010-05-26
52
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. In this way the North American Indians produce pemmican (dried meat ground into powder and made into cakes), the Scandinavians make stock fish and the Arabs dried dates (枣) and "apricot leather" (杏干).
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 (硫磺) before drying. Plums (李子), for making prunes (梅干), and certain varieties of grapes for making raisins (葡萄干) and small dried grape cakes, are dipped in a salt solution in order to crack the skins of the fruit slightly and remove their wax coating, thus increasing the rate of drying.
Nowadays most foods are dried mechanically. The conventional method of such dehydration (脱水) is to put food in chambers through which hot air 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, cut meat, and fish.
Liquids such as milk, coffee, tea, soups and eggs may be dried by pouring them over a heated horizontal steel roller or by spraying them into a chamber through which a current of hot air passes. In the first case, the dried material is removed off the roller as a thin film which is then broken up into small, though still relatively coarse thin pieces. In the second process it falls to the bottom of the chamber as fine powder. Where recognizable pieces of meat and vegetables are added, as in soup, the ingredients are dried separately and then mixed.
How long has tile open-air method of drying food been known by man?____________
选项
答案
For hundreds of years/centuries.
解析
转载请注明原文地址:https://kaotiyun.com/show/94j7777K
0
大学英语四级
相关试题推荐
A、Heenjoysplayingchess.B、Hehatesplayingchess.C、Hecan’tplaychess.D、Hewasnotagoodstudent.A根据四个选项,推测对话的内容与chess相关
Thenexttimeyouattendasocialfunctionorgotoaplacewherepeoplemeetandinteract,takenoteofthenumberofpeoplewh
Acollegeeducationisaninvestmentinthefuture.Butitcanbea【B1】______investment.TheCollegeBoard【B2】______thatthe
A、Notgettingwhathewants.B、Acustomthatisnewtohim.C、Callingupcustomers.D、Someofhisgoodfriends.B根据选项,推测提问涉及对话的内
Singaporeiswellknownasamulti-racial,multi-culturalandmulti-religiousnation.Andthis【C1】______isgraduallybecoming
Wefindthatbrightchildrenarerarelyheldhackbymixedabilityteaching.Onthecontrary,boththeirknowledgeandexperienc
RobertSpring,a19thcenturyforger(伪造者),wassogoodathisprofessionthathewasabletomakehislivingfor15yearsbyse
Childrenmodelthemselveslargelyontheirparents.Theydosomainlythroughidentification.Childrenidentify【C1】______apar
OldageandseniorityalonedonetcommandauthorityamongtheBritish:infactmodemlifebasbeendevelopingsofastthatold
A、Theuniversityasawhole.B、Anassociationofteachersandscholars.C、Asocietyoflegalprofessionals.D、Abusinesscorpora
随机试题
先进的生产关系之所以能促进生产力的发展,是由于()。
我们必须知道那些用以表示化学元素的符号。
A.凹透镜B.凸透镜C.圆柱镜D.平面镜E.多棱镜
我国民法所调整的财产关系具有()特点。
各分支局负责所辖地区企业出口玩具的报检放行工作。( )
下列关于企业劳动争议仲裁的表述错误的是()。
设计教学环节要能够体现语言、语言学习和语言教学的规律。(暨南大学2017)
微分方程满足y|x=1=1的特解为_________.
Everything________intoconsideration,IproposethatthefirstprizeshouldbegiventoLinQiang.
AstheworldexcitedlygreetedSnuppy,thefirstcloneddog,commentatorscelebratedourcleverness.Manyfeelproudthatourag
最新回复
(
0
)