Canning kit questions...

[ecudc]

I know the one thing you need if you are bottling anything other than tomatoes and other high acidity items like fruit juice is pressure. To ensure botulism is killed for long term storage you need to get the temp up past 118 degrees c (245????F) which you can't do without pressure.

The salt and citic acid/lemon is to make the tomato more acidic just in case as tomatoes can be a bit boarderline when it comes to having enough acidity.

[Thelma Sanders]

I know the one thing you need if you are bottling anything other than tomatoes and other high acidity items like fruit juice is pressure. To ensure botulism is killed for long term storage you need to get the temp up past 118 degrees c (245????F) which you can't do without pressure.

The salt and citic acid/lemon is to make the tomato more acidic just in case as tomatoes can be a bit boarderline when it comes to having enough acidity.

As the OP only wants to preserve tomatoes, I don't really think we need to frighten people about botulism, do we? As long as the jars are sterile and they are boiled for long enough (as per charts) they are completely safe.
In America/Canada they can fish, meat, poultry and a lot of home-grown/cooked produce and I agree, those do need a different mindset and method of canning, to be completely safe.
Horses for courses

[ecudc]

Actually there is quite a bit of a debate whether modern tomato varieties which have often have lower levels of acidity than heritage varieties can be bottled without either the addition of lemon/citric acid or pressure canning. the Op asked why people were adding citric acid in the videos she was watching. That's the reason.There is about one case of botulism from home preserved tomatoes every 5 years in the states so small numbers But not impossible.