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Troubleshooting Tomato Canning: Checking Seals and Spoilage Signs

Introduction

Jars that don't "ping" after canning may still be sealed, but verification is critical.

Testing Jar Seals

Lids should be sucked down without pressing.
Wait a couple of weeks: unsealed jars develop bubbles, off-odors, or discoloration.

Reprocessing Unsealed Jars

If unsure, reprocess in a hot water bath with rings loosened. Use new lids if seals broke. A hot water bath is recommended for tomatoes (pressure canner not required).

Signs of Spoilage

Bulging lids, leaks, mold, foam, or foul smell upon opening indicate spoilage—discard immediately.

Conclusion

When in doubt, reprocess with new lids. 20 jars are worth the cost of new lids for peace of mind.

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