As fall approaches, fall gardens will start to wind down. Tomato plants may still be producing tasty tomatoes, which can be enjoyed fresh. But if a frost or freeze has occurred while tomatoes are on the vine, do not can those tomatoes. Preserve them by freezing or dehydrating for later use.
These tomatoes may have a pH level greater than 4.6 and may have extra pathogens. The canning process time may not be enough to kill extra organisms. This could lead to a product that spoils and is unsafe to eat.
Over-ripe tomatoes are less acidic. The acidity level in tomatoes varies throughout the growing season. Tomatoes reach their highest acidity when they are still green and decrease in acidity until they reach their lowest acidity as they mature.
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