Are food preservatives bad for you? - Eleanor Nelsen
View full lesson: http://ed.ted.com/lessons/are-preservatives-bad-for-you-eleanor-nelsen Food doesn't last. In days, sometimes hours, bread goes moldy, apple slices turn brown, and bacteria...
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Food doesn't last. In days, sometimes hours, bread goes moldy, apple slices turn brown, and bacteria multiply in mayonnaise. But you can find all of these foods out on the shelf at the grocery store, hopefully unspoiled, thanks to preservatives. But what exactly are preservatives? How do they help keep food edible and are they safe? There are two major factors that cause food to go bad: microbes and oxidation. Microbes like bacteria and fungi invade food and feed off its nutrients. Some of these can cause diseases, like listeria and botulism. Others just turn edibles into a smelly, slimy, moldy mess. Meanwhile, oxidation is a chemical change in the food's molecules caused by enzymes or free radicals which turn fats rancid and brown produce, ...
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Food doesn't last. In days, sometimes hours, bread goes moldy, apple slices turn brown, and bacteria multiply in mayonnaise. But you can find all of these foods out on the shelf at the grocery store, hopefully unspoiled, thanks to preservatives. But what exactly are preservatives? How do they help keep food edible and are they safe? There are two major factors that cause food to go bad: microbes and oxidation. Microbes like bacteria and fungi invade food and feed off its nutrients. Some of these can cause diseases, like listeria and botulism. Others just turn edibles into a smelly, slimy, moldy mess. Meanwhile, oxidation is a chemical change in the food's molecules caused by enzymes or free radicals which turn fats rancid and brown produce, ...
