Verification of USDA Home‐Canning Recommendations for Tomatoes Processed at High Altitudes

Survivability of spoilage bacteria in tomatoes home-preserved at high altitude was studied. Thermal-processing followed USDA guidelines for two elevations (1540m and 2150m) and two process methods (boiling water-bath and pressure). Three treatments of Bacillus coagulans spores (no added spores, 104 and 105 spores/jar) were used. Processing method, elevation or inoculum level had no effect on post-processing count (P> 0.05), but over all treatment groups, surviving bacteria were found in 19.4% of the jars. Even though tomatoes processed up to 2150 m elevation were verified as safe, detectable surviving bacteria in some jars indicated processing guidelines were minimal.