| 摘要 |
259,948. California Fruit Growers Exchange, (Assignees of Jameson, E.). Oct. 17, 1925, [Convention date]. Gums, carbohydrate and like.-Pectin preparations, crude or partly purified, which generally have a pH value too low for effective or regulated jellification, are treated with a salt of a strong base and a weak acid in such proportions that the pH of the finished product lies between 3.4 and 7, but not including 7. Where the pectin product has been purified with a strong acid, and contains traces of it, the product may be suspended in alcohol and the strong base-weak acid salt added in proper amount, after which the pectin is separated, washed with alcohol and dried. Alternatively the pectin product may be mixed with the proper amount of the dry salt, so that when dissolved, the pH will fall within the defined limits. In a modification, particularly for use with pectin products which have not been treated with strong acid, in addition to the dry salt, dry organic acids such as citric or tartaric acids are mixed;, so that when dissolved the pectin is standardized as to pH. Suitable salts comprise sodium citrate or acetate; and effervescent salts such as sodium carbonate or bicarbonate are particularly effective in promoting ready solution and reaction. The amounts of salt or acid to be added are determined by titration of the pectin products in alcoholic suspension with standard alkali, or by making sample jellies with pectins containing varying known amounts of salt &c. Specification 239,635 is referred to. |
