| 摘要 |
Propylene or butylene glycol used for preserving coconut is freed from carbonyl-containing impurities, e.g. aldehydes and ketones, and their precursors, e.g. acetals and ketals, by fractionally distilling the glycol under reduced pressure, by adding sulphur dioxide to it, by bringing it into contact with alumina or an ion exchange resin, e.g. first with a polyphenol resin and then with a polyamine resin, or by adding potassium hydroxide, sodium hydroxide or lithium hydroxide to the glycol and then distilling it off. Specification 639,938, [Group VI], is referred to.ALSO:To preserve coconut and prevent it turnning yellow, propylene or butylene glycol freed from carbonyl-containing impurities, e.g. aldehydes and ketones, and their precursors, e.g. acetals and ketals, is added to the coconut which may be in the form of threads, shreds or small pieces containing from 5 to 15 per cent of moisture. Specification 639,938 is referred to. |
