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
Why does cream go bad faster than butter? Some researchers think they have the answer, and it comes down to the structure of the
Why does cream go bad faster than butter? Some researchers think they have the answer, and it comes down to the structure of the
admin
2014-09-18
32
问题
Why does cream go bad faster than butter? Some researchers think they have the answer, and it comes down to the structure of the food, not its chemical composition---a finding that could help rid some processed foods of chemical preservatives.
Cream and butter contain pretty much the same substances, so why cream should sour much faster has been a mystery. Both are emulsions--tiny globules of one liquid evenly distributed throughout another. The difference lies in what’ s in the globules and what’ s in the surrounding liquid, says Brocklehurst, who led the investigation.
In cream, fatty globules drift about in a sea of water. In butter, globules of a watery solution are locked away in a sea of fat. The bacteria which make the food go bad prefer to live in the watery regions of the mixture. "This means that in cream, the bacteria are free to grow throughout the mixture," he says.
When the situation is reversed, the bacteria are locked away in compartments buried deep in the sea of fat. Trapped in this way, individual colonies cannot spread and rapidly nm out of nutrients. They also slowly poison themselves with their waste products. "In butter, you get a serf-limiting system which stops the bacteria growing," says Brocklehurst.
The researchers already working with food companies keen to see if their products can be made resistant to bacterial attack flux)ugh alterations to the food’s structure. Brocklehurst believes it will be possible to make the emulsions used in salad cream, for instance, more like that in butter, The key will be to do this while keeping the salad cream liquid and not turning it into a solid lump.
The underlined word "colonies" in Paragraph 4 refers to______
选项
A、tiny globules
B、watery regions
C、bacteria communities
D、little compartments
答案
C
解析
在这四个选择项中只有"bacteria communities"可以作spread and rapidly run out of nutrients的主 语,而其他三个选择项作主语,均不符合逻辑。由此C 是正确答案。
转载请注明原文地址:https://kaotiyun.com/show/QoHK777K
0
专业英语四级
相关试题推荐
Issuesofprice,place,promotion,andproductare______conventionalconcernsinplanningmarketingstrategies.[2004]
Iamoneofthemanycitypeoplewhoarealwayssayingthatgiventhechoicewewouldprefertoliveinthecountryawayfromth
Someproductsrespondtoconsumers’needs;others,likeSony’sairboard,seektocreatethem.Likesendinge-mailsfromthepool
Theymaybejustpassingyouroffice,computerbagslungoveroneshoulder.Ortheymaybesittinginacaroutsideit,casually
Theymaybejustpassingyouroffice,computerbagslungoveroneshoulder.Ortheymaybesittinginacaroutsideit,casually
AsoneofEurope’sleadingculturalcitiesBerlinoffersmanymuseums,historicsitesandotherplacesforamemorablevisit.
Foranysurfer,nothingbeatstheideaofjusthangingoutinabeachridingthewavesallday.Thethrillofridinggiantbreak
ExperiencedobserversonAmericancampuseshavebeguntonoticeanewgroupofmothersandfathersemergingoverthepasttwoye
The_______crownjewelsarekeptintheTowerofLondon.
Tosurviveintheintensetradecompetitionbetweencountries,wemust______thequalitiesandvarietiesofproductswemaketo
随机试题
对蛛网膜下腔阻滞麻醉(腰麻)术后并发低压性头痛的处理,下列哪项是不恰当的
用煮沸灭菌法杀灭芽孢至少需多长时间
A、小便淋沥不已,遇劳即发B、小便淋漓,浑浊如米泔水C、小腹胀满,小便艰涩疼痛,尿后余沥不尽D、起病急骤,小便赤热,溲时灼痛E、排尿时突然中断,尿道窘迫疼痛石韦散主要用于
女患者,停经四月余,身体渐而消瘦,潮热盗汗,五心烦热,舌红苔少,脉细数。首选方是
王某,男,40岁,行肺段切除术后2小时,自觉胸闷、呼吸急促。血压、脉搏正常,水封瓶内有少量淡红色液体,长玻璃管内的水柱不波动。应考虑为
规划审批机关对依法应当编写有关环境影响的篇章或者说明而未编写的规划草案,依法应当附送环境影响报告书而未附送的专项规划草案,违法予以批准的,对直接负责的主管人员和其他直接责任人员,由上级机关或者监察机关依法给予()。
甲企业拟新增一投资项目,年初一次性投资500万元,可使用年限为3年,当前市场利率为9%,每年年末能得到200万元的现金净流量,则该项目的净现值为()万元。[已知:(P/A,9%,3)=2.5313]
"Yearsago,afriendofmineobservedthat80percentofthepeopleinthiscountryhavetoomuchself-esteemand20percenthav
提出动机的自我效能感理论的心理学家是
物流具有三种表现形式,即物流的物质表现形式、价值表现形式和信息表现形式。物流的物质表现形式是指(41)。
最新回复
(
0
)