shelf stable tomato sauce

I'm doing some canning and i'm thinking about trying to make some shelf stable tomato sauce. Can i make the sauce, then bag it and cook it at a high enough temperature for a certain amount of time to make it shelf stable? Any help here would be great.

Find more posts tagged with

All About Ingredients

Comments

Tim_Sutherland_52834

From memory, you can not SV anything and make it shelf stable. You can seal food in retort bags and then "can" for shelf stable product in flexible bags.

The USDA has good information on home canning.

Chris_Young_80640

In theory, you could sous vide a tomato sauce at a boil and achieve shelf-stability, BUT ONLY if the pH of the sauce is below 4.3, and often tomatoes are not quite acidic enough. The only way to know for sure is check the pH with a meter or litmus paper.

Above this pH, and it needs to be pressure canned. There are special flexible retort bags that can withstand pressure canning, but they're hard to find and expensive. Glass canning jars are an easier option.

The other problem with using sous vide packaging for canning, even if the sauce is acidic enough, is that they are not as air-tight as they seem. And after weeks or months, you will start to get damaging oxidation.

If you want to do a great job of preserving a homemade tomato sauce, my recommendation is to add it hot to glass canning jars, and then place these jars in a 70 °C sous vide bath for about an hour. Then keep them refrigerated. They'll last a very long time in the fridge, even though they are not technically "canned" because you didn't boil them. This was a technique pioneered in the 1960s by E.H. Kohlman who called it frigi-canning.

Jonathan_Hunter_76993

Why is boiling important. Couldn't a ph drop and some heat application kill off everything. Good point about air getting back in.

Chris_Young_80640

@Jonathan — Theoretically, yes, but the problem is the USDA doesn't actually list what organisms they're truly concerned about in low pH (acidic) canned goods. While working on MC, I was in touch with one of the USDA scientists and she admitted that although they had developed standards, the original underlying data had mostly been lost, so there is know way to rationalize a lower temperature, longer holding time process without doing all of the original research over again (most of the original work was done in the 40s and 50s)

ParkerCook_66639

I just made a batch of tomato sauce that has a large amount of whole garlic. The sauce is cooked for four hours but canning the garlic gives me worries. Before I can the sauce should I remove the garlic or would it be fine? From what I understand it's garlic in oil that causes problems.

Sunnie_482760

I've seen some instructional videos for processing pickles for shelf stabilization lately.

Eric_Olsson_390802

Hey Chris, funny to pick up the discussion 6 years later, but I just found a local source of San Marzano tomatoes and have been researching the past couple of days on the best way to make passata from them.

I have Modernist Cuisine and first learned about frigi-canning there. I've also been reading about the issue of tomatoes usually not having quite a low enough pH for traditional canning, and but I'm very reluctant to add anything to this insanely good batch of tomatoes, so frigi-canning looks like the way to go. Can you point us to any other resources on frigi-canning or cook-chill sous vide?

Chris_Young_80640

I would follow boiling water canning recipes for the size of jars you’ll be using, but you can reduce the temperature to, say, 65C provided you refrigerate afterwards. Lower temps and longer times are possible, but it requires knowing more about how long it will take for everything in the jars to come up to pasteurization temperature.