ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

食物防腐剂到底是好是坏 – 译学馆
未登录,请登录后再发表信息
最新评论 (0)
播放视频

食物防腐剂到底是好是坏

Are food preservatives bad for you? - Eleanor Nelsen

【启点字幕组】
Light up the world
食物不会一直保持新鲜
Food doesn’t last.
不用几天 有时甚至几个小时内 面包就会发霉
In days, sometimes hours, bread goes moldy,
切片苹果就会表面发黄生锈
apple slices turn brown,
蛋黄酱中就会滋生细菌
and bacteria multiply in mayonnaise.
但是 杂货店货架上摆着的所有这些食物
But you can find all of these foods out on the shelf at the grocery store,
应该都还没变质
hopefully unspoiled,
这都要归功于防腐剂
thanks to preservatives.
但是 防腐剂到底是什么东西呢
But what exactly are preservatives?
它又是如何让食物保持新鲜 安全可食用的呢
How do they help keep food edible and are they safe?
食物变质主要有两个原因
There are two major factors that cause food to go bad:
微生物和氧化作用
microbes and oxidation.
像细菌和真菌这样的微生物会侵入食物
Microbes like bacteria and fungi invade food
吸取食物中的营养
and feed off its nutrients.
像李斯特菌 肉毒杆菌这种微生物
Some of these can cause diseases,
则会引起疾病
like listeria and botulism.
而其他的微生物只会让食物变成臭臭黏黏的 发霉的一坨
Others just turn edibles into a smelly, slimy, moldy mess.
同时 食物分子之间也会发生化学变化–氧化
Meanwhile, oxidation is a chemical change in the food’s molecules
酶和自由基都能引起氧化发生
caused by enzymes or free radicals which turn fats rancid
从而使油脂腐败 表面变棕 就像苹果和土豆那样
and brown produce, like apples and potatoes.
食物防腐剂能够阻止这两种变化的发生
Preservatives can prevent both types of deterioration.
在人类发明人工制冷之前
Before the invention of artificial refrigeration,
真菌和细菌能够在食物中大量滋生
fungi and bacteria could run rampant in food.
所以 人类想方设法创造不适合微生物生存的恶劣环境
So we found ways to create an inhospitable environment for microbes.
举个例子 在食物中加入酸性物
For example, making the food more acidic unravels enzymes
去分解微生物存活必须的酶
that microbes need to survive.
但有些细菌其实是有益的
And some types of bacteria can actually help.
几千年以来 人们使用可以产生乳酸的细菌
For thousands of years, people preserved food using bacteria
来保存食物
that produce lactic acid.
易腐烂的蔬菜 牛奶 在乳酸作用下
The acid turns perishable vegetables and milk
能够保存得更久
into longer lasting foods,
像欧洲的德国酸菜
like sauerkraut in Europe,
韩国的泡菜
kimchi in Korea,
中东的牛奶 都是用这种方法保存的
and yogurt in the Middle East.
这些处理过的食物中所含的有益微生物还能促进肠胃消化
These cultured foods also populate your digestive track with beneficial microbes.
许多人造防腐剂也都是酸
Many synthetic preservatives are also acids.
沙拉里面的安息香酸
Benzoic acid in salad dressing,
奶酪中的山梨酸钾
sorbic acid in cheese,
以及烘培食物中的丙酸
and propionic acid in baked goods.
这些酸都安全么
Are they safe?
一些报告显示 安息香酸盐与安息香有关
Some studies suggest that benzoates, related to benzoic acid,
会让人兴奋过头
contribute to hyperactive behavior.
但所得出的结论并不确凿
But the results aren’t conclusive.
否则 这些酸似乎都是百分百安全的
Otherwise, these acids seem to be perfectly safe.
另一个防止微生物滋生的方法就是 像果酱这样在食物中加大量的糖
Another antimicrobial strategy is to add a lot of sugar, like in jam,
或者像腌肉一样在食物中加入大量盐
or salt, like in salted meats.
糖和盐能够吸收微生物所需的水
Sugar and salt hold on to water that microbes need to grow
也可以吸收细胞外的水分
and actually suck moisture out of any cells that may be hanging around,
从而摧毁细胞
thus destroying them.
当然 摄入过多的糖和盐会增加你得心脏病的风险
Of course, too much sugar and salt can increase your risk of heart disease,
并提高得糖尿病
diabetes,
和高血压的几率
and high blood pressure,
所以只有适量食用 这种食物防腐剂才能达到最佳效果
so these preservatives are best in moderation.
盐腌的肉类里常常含有抗菌的硝酸酯 亚硝酸盐
Antimicrobial nitrates and nitrites, often found in cured meats,
它们能够阻挡引起肉毒中毒的细菌 但同时也会导致其他健康问题
ward off the bacteria that cause botulism, but they may cause other health problems.
一些研究表明 癌症与盐腌肉有关
Some studies linking cured meats to cancer
并指出 这些食物食物剂可能也是罪魁祸首
have suggested that these preservatives may be the culprit.
同时 抗氧化性的食物防腐剂
Meanwhile, antioxidant preservatives prevent the chemical changes
能够防止化学变化 防止食物变味或变色
that can give food an off-flavor or color.
千百年来 人们都通过烟熏来保存食物
Smoke has been used to preserve food for millennia
因为 木头燃烧产生的一些芳香化合物有抗氧化作用
because some of the aromatic compounds in wood smoke are antioxidants.
在发现食品冷冻法之前
Combining smoking with salting was an effective way of preserving meat
将盐腌过的肉进行烟熏处理是最有效的保存方法
before refrigeration.
至于没有烟熏味的抗氧化剂
For antioxidant activity without a smoky flavor,
有像二丁基羟基甲苯和生育酚这样的化合物
there are compounds like BHT and tocopherol,
也就是维生素E
better known as vitamin E.
就像烟熏过程中产生的化合物一样
Like the compounds in smoke, these sop up free radicals
它们能够吸收自由基
and stave off rancid flavors
除去油 奶酪 谷物
that can develop in foods like oils,
等食物中
cheese,
散发的臭味
and cereal.
其他抗氧化剂 比如柠檬酸和抗坏血酸[维生素C]
Other antioxidants like citric acid and ascorbic acid
通过阻止合成使食物变棕的酶
help cut produce keep its color
来保持食物原本的颜色
by thwarting the enzyme that causes browning.
像亚硫酸盐等的合成物具有多重功效
Some compounds like sulfites can multitask.
它们既有抗微生物性又有抗氧化性
They’re both antimicrobials and antioxidants.
有些人会对亚硫酸盐过敏
Sulfites may cause allergy symptoms in some people,
但大多数抗氧化防腐剂被普遍认为是安全的
but most antioxidant preservatives are generally recognized as safe.
那么 食物防腐剂到底值得你忧心吗
So should you be worried about preservatives?
由于含量甚微
Well, they’re usually near the end of the ingredients list
它们通常出现在食品成分列表的结尾处
because they’re used in very small amounts
在美国食品和药物管理局制定的安全食用剂量范围内
determined by the FDA to be safe.
然而 一些消费者和公司
Nevertheless, some consumers and companies
都想找到食品防腐剂的替代品
are trying to find alternatives.
他们从食物包装下手 比如说减少食物与氧气的接触
Packaging tricks, like reducing the oxygen around the food can help,
但要是没有某些化学剂品辅助
but without some kind of chemical assistance,
没有多少食物能长时间保持新鲜
there are very few foods that can stay shelf stable for long.

发表评论

译制信息
视频概述
听录译者

收集自网络

翻译译者

启点-卷卷

审核员

自动通过审核

视频来源

https://www.youtube.com/watch?v=ZJU34yTJL4M

相关推荐