How NOT to can tomatoes: In yesterday’s RTS, we talked about the most current information on how to can tomatoes, one of the most common items people choose to can at home. Today, we will discuss the various recommendations for what to avoid if you do plan to try your hand at home canning with tomatoes as your subject.

Avoid the open kettle method, i.e. heating the product, spooning into jars and putting the lids on to wait for them to pop with no other processing. This can lead to the product becoming spoiled by microorganisms that aren’t properly destroyed.

It is also unwise to try oven canning or using so-called canning powders, like aspirin.

Do NOT use half gallon jars if you plan to can tomato juice. These are created for grape and apple juice. Instead, opt for the quart size or smaller whenever you want to can any tomato product.

Do NOT make up your own recipe for salsa, pizza or spaghetti sauce. When creating your own recipe, you may leave out important ingredients that are specifically added to improve the flavor — these are generally low acid ingredients.

Make sure to use recipes that are up-to-date and that have been scientifically researched.

Do NOT add extra low acid ingredients. Keep in mind that it is ok to omit an ingredient like garlic, but the recommended ratio is three cups of celery, onions, carrots and peppers for 22 pounds of tomatoes when canning tomato-vegetable juice blends.

Do NOT add milk or thickeners. Instead, if you are hoping to create tomato soup or stewed tomatoes, save those ingredients to add when you plan to serve the tomatoes.

The tips from both today’s RTS and the previous one can be used for low-acid tomatoes, regular tomatoes and yellow tomatoes.

If you happen to have questions about the process, it might be wise to read further at https://extension.psu.edu/lets-preserve-tomatoes.