Is it necessary to add the amount of lemon or lime juice or vinegar called for in a Pomona’s Pectin recipe?
Yes, for safe water bath canning it’s important to add the lemon or lime juice or vinegar if called for in a Pomona’s Pectin recipe. In some cases, the added acid may be also be required for the jam or jelly to jell properly with Pomona’s
To be safe for water bath canning, the fruit mixture must be what is considered “high acid,” which means the pH must be 4.6 or below. Many fruits are high acid naturally. But fruits that are considered to be “lower acid” and/or fruits and vegetables that are considered to be “low acid,” need lemon or lime juice or vinegar added to bring down their pH into the “safe for water bath canning” range.
If you are converting a recipe or developing your own, go to Get Creative for information about which fruits require additional acid with Pomona’s Pectin and the amount required for each fruit.