首页
登录
职称英语
Natural flavorings and fragrances are often costly and limited in supply. Fo
Natural flavorings and fragrances are often costly and limited in supply. Fo
游客
2023-12-30
43
管理
问题
Natural flavorings and fragrances are often costly and limited in supply. For example, the essential ingredient in a rose fragrance is extracted from natural rose oil at a cost of thousands of dollars a pound; an identical synthetic substance can be made for 1% of this cost. Since the early twentieth century, success in reproducing these substances has created a new industry that today produces hundreds of artificial flavors and fragrances.
Some natural fragrances are easily synthesized; these include vanillin, the aromatic ingredient in vanilla, and benzaldehyde, the aromatic ingredient in wild cherries. Other fragrances, however, have dozens, even hundreds of components. Only recently has it been possible to separate and identify these ingredients, by the use of gas chromatography and spectroscopy. Once the chemical identity is known, it is often possible to synthesize them. Nevertheless, some complex substances, such as the aroma of fresh coffee, have still not been
duplicated
satisfactorily.
Many of the chemical compounds making up these synthetics are identical to those found in nature, and are as harmless or harmful as the natural substances. New products must be tested for safety, and when used in food, must be approved by the U.S. Food and Drug Administration.
The
availability
of synthetic flavors and fragrances has made possible a large variety of products, from inexpensive beverages to perfumed soap to used cars with applied "new car odor". [br] During the global COVID-19 pandemic, the team worked hard to help customers
suffered
financial hardship,
enabled
them to keep their cover in place through financial assistance processes.
选项
A、who were suffering; enabling
B、suffering; enabled
C、who had suffered; which enabled
D、who were suffered; and enabled
答案
A
解析
转载请注明原文地址:http://tihaiku.com/zcyy/3318340.html
相关试题推荐
With2005fastbecoming"theyearofthenaturaldisaster",itistimetore
With2005fastbecoming"theyearofthenaturaldisaster",itistimetore
With2005fastbecoming"theyearofthenaturaldisaster",itistimetore
With2005fastbecoming"theyearofthenaturaldisaster",itistimetore
With2005fastbecoming"theyearofthenaturaldisaster",itistimetore
With2005fastbecoming"theyearofthenaturaldisaster",itistimetore
With2005fastbecoming"theyearofthenaturaldisaster",itistimetor
With2005fastbecoming"theyearofthenaturaldisaster",itistimetor
With2005fastbecoming"theyearofthenaturaldisaster",itistimetor
With2005fastbecoming"theyearofthenaturaldisaster",itistimetor
随机试题
Hello,welcometo“ThisWeek’sSports”.Itwillbe9:00a.m.whentheLosA
SuggestionsforEffectiveResearch-basedAssignmentsI.Thefunc
There’snoquestionthattheEarthisgettinghotter.Therealquestionsare:Ho
高中历史《文明的链接》 一、考题回顾 题目来源:5月18日江西省南昌市面
甲、乙、丙三人按35%,55%,10%的份额共有一艘渔船,乙、丙2人均有意卖掉渔
对信息系统进行管理的职能包括:A.向使用计算机服务的用户部门收取一定费用的制度
蒿芩清胆汤中不含有的药物是()。A.淡竹茹B.赤茯苓C.陈广皮D.碧玉散E.芍
价格制定阶段的()目的是通过分析现在与未来的市场竞争情况,了解市场的大环境及
战国七雄包括()。 A.秦、齐、楚、燕、韩、赵、魏B.秦、晋、楚、越、韩、
教育学成为一门独立学科.以()的《大教学论》的发表为标志。 A.赫尔巴特 B
最新回复
(
0
)