| 摘要 |
To prevent presetting in making jams and jellies from fruit such as cranberries, blueberries, tart plums, &c., having a high content of quicksetting pectin, or from juice from such fruit, this pectin is first wholly or partially destroyed or rendered innocuous, e.g. by enzymatic action. The enzyme used may be pectinase, or an enzyme preparation derived from Pencillium glaucum employed in solution or precipitated by means of alcohol &c. and used in solid form, and the fruit material is kept during the treatment, which takes about 12 hours, at the optimum temperature for the enzymatic action, e.g. 25-50 DEG C. The fruit material is preferably brought to a pH value of 3,1 to 3,5 prior to the treatment. In preparing jam and jelly, there is added to the treated material sugar and pectin, preferably a slow setting pectin, but fruit or fruit juice from which the pectin has not been eliminated may be employed instead, and the mixture is boiled until the solid content reaches 65 per cent. The fruit may be softened, pulped or disintegrated before treatment. |
