Can I heat home-canned low acid foods in the microwave for several minutes before tasting instead of the usual 10 minutes on my range?
You don't need to boil low-acid foods before eating if you are sure the foods were canned according to instructions in current University Extension guidesheets. If you have any doubts about the canning methods used, boil the food before tasting it--10 minutes below 1,000 feet, 11 minutes above 1,000 feet. Since this is a time/temperature relationship, foods heated in the microwave would have to be heated for the same amount of time (10 minutes). There is no research to indicate that this time can be decreased. Most vegetables would lose considerable quality when boiling at full power in a microwave for 10 minutes. Also, due to the uneven heating pattern of microwaves, cold spots could protect botulism toxin from destruction.
Reference: Pat Kendall - Colorado Coop Extension - newspaper article
Last update: Tuesday, May 05, 2009