Some of the best tips for preserving tomatoes is to not use open kettle canning, make sure the lids are secure before storing, and know how to preserve raw tomatoes. Open kettle canning is known to increase the risk of spoilage, so experts usually advise against its use. The boiling method is one of the best methods for preserving tomatoes, but it is important to ensure the lid is secure and does not make a popping sound when pressed. In addition, it may be necessary to know how to properly preserve raw tomatoes from an overflowing garden to can at a later date. Canned tomatoes can be kept for up to a year and a half.
Open kettle canning is no longer recommended by experts for preserving tomatoes. The method has a higher risk of spoilage than some other methods. It can still be used with caution, but eating spoiled tomatoes may cause food poisoning. Food poisoning sometimes requires a trip to a medical facility if it is particularly severe. Therefore, most people do not consider open kettle canning to be worth it.
When using the boiling method, the canned tomatoes should be left to cool. Some people let the cans cool for a few hours before touching the lids to make sure they are secure. Other people choose to let the cans sit over night before touching the lids. It is common practice to place the ones with loose lids in the refrigerator to use soon. Reprocessing the jar may increase the risk of spoilage.
To preserve raw tomatoes, they should be kept in the pantry for up to five days or until fully ripe. Placing them in the refrigerator when still green results in a less flavorful tomato. After that, they can be kept in the refrigerator for up to three days, followed by two months in the freezer. Raw tomatoes can be frozen with or without skins, chopped or whole, and in bags or freezer-safe containers. Thawed tomatoes are softer than fresh raw tomatoes, and best used in dishes like spaghetti and tomato-based soup.
After canning, it is usually recommended that the tomatoes be kept for no longer than 18 months. Preserving tomatoes by canning can keep the tomatoes from spoiling for longer than that, however. The 18-month rule is followed to throw away tomatoes that no longer have the most optimum flavor and texture, though they are usually safe to consume.