Canning season is upon us and we receive many calls each year about canning safely. I don’t very often run across half gallon jars but I happened to just this last weekend. Although it is possible to can something in smaller jars using the same amount of time as the next size larger jar it is not true in reverse. There are no formulas for extending the processing time for a larger jar.
The only processes that USDA, National Center for Home Food Preservation, and University of Georgia have to recommend for half gallon jars are for very acidic fruit juices. Those would be apple juice and grape juice and ONLY the juice is allowed. There are no research-tested boiling water processes for other foods for jars larger than those published with recipes.
I am including the recipes for apple juice and grape juice in case you are interested in canning those. Please remember those are the ONLY two things that can be safely canned in half gallon jars. There are no tested recipes for other juices.
Please call AnswerLine if you have any questions about canning safely!