UNSATURATED OILS CAN BE HYDROGENATED

1. unsaturated veggie oils are liquid at room temperature
2. they can be hardened by reacting with hydrogen in the presence of a nickel catalyst at about 60 degrees C
3. Hydrogenated oils have higher melting points than unsaturated oils so they're more solid at room temperature. This makes them useful as spreads and for baking cakes and pastries
4. Margarine is usually made from partially hydrogenated veggie oils - turning all the double bonds in veggie oil to single bonds. This would make margarine too hard and difficult to spread. Hydrogenating most of them gives margarine a nice, buttery, spreadable consistency
5. partially hydrogenated veggie oils are often used instead of butter in processed foods, e,g, biscuits. These oils are a lot cheaper than butter and they keep longer . This makes biscuits cheaper and gives them a longer shelf life.
6. But partially hydrogenating vegetable oils means that end up with a lot of so-called trans-fats. And there's evidence to suggest that trans fats are very bad for you.

	Erstellt von charis.lydia vor etwa 11 Jahre

GCSE Chemistry Notiz am PLANT OILS, erstellt von charis.lydia am 31/05/2013.