{'fraction_non_alphanumeric': 0.024489795918367346, 'fraction_numerical': 0.012244897959183673, 'mean_word_length': 4.874251497005988, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Tomato Acidity and the Safety of Home Canned Tomatoes


Fifty-eight cultivars of tomatoes were screened for the occurrence of high pH fruit. Although large differences in pH were found between and within cultivars, no pH values high enough to permit the growth of Clostridium botulinum were obtained. pH and titratable acidity were not highly correlated. Tomato acidity data obtained from 57 locations in 23 states for 356 cultivars and 212 breeding lines were compiled and analyzed to identify trends. These data show that small-fruited, light colored and “new” cultivars are not low in acid, as is commonly believed. A few high pH data points (pH ⩾ 4.7) were associated with specific cultivars, locations, and conditions (overripening). The response of some higher pH cultivars to acidulation with citric acid was determined; a linear relationship between pH and added acid was found. These data were used to evaluate several methods of acidulation recommended for home canners.