We may need a microbiologist to explain this. There are several Forum members who have a science background.

As I understand it, bacteria feed on proteins and carbohydrates (i.e. natural sugars). They also like low-acidity and water. Therefore, something like meat is particularly high-risk for bacterial growth if not properly processed.

Now, the added sugar question. In this case you're providing a low-acid environment through the addition of a great deal of vinegar. Sugar does not change pH, so no worries there. Sugar is also a desiccant. In other words, it reduces the water available to the bacteria. This chili sauce is high-acid, high-sugar and therefore safe.

I have never heard of any risk associated with too much processed sugar in a recipe (except to your teeth).

Your recipe is roughly 30 cups of marginal to low-acid veggies (25 c. tomatoes, 4 1/2 c. onions, 3/4 c. hot peppers) to 4 cups vinegar. The NCHFP recipe for Spicy Chili Sauce is 20 cups product to 1 1/2 cups vinegar, so your recipe is, if anything, even "more safe." (A paradox, but I'll let it stand.)

What can happen is the density is greater due to all the sugar and that might mean a longer processing time. You could always increase to 20 minutes for more comfort. It won't hurt the sauce.

(With all that sugar cook it down far enough and you'll have tomato jam!)

Carol

I'm assuming you meant to say high-acid in this sentence?
"In this case you're providing a low-acid environment through the addition of a great deal of vinegar."

The waist-line might also feel the effects of so much sugar. It's surprising that I like this recipe so much. I'm normally a heavy-on-the-salt person, but my relishes all tend to be sweet. Ah well, I'll use most of it in lieu of ketsup on hot dogs and hamburgers and that spreads consumption out over a year

Thanks so much for the info and thanks for using layman's terms. (I cooked one batch waaaay down and it did resemble jam -- the hot dogs loved it.)

Well, shoot. Yes, I meant to say high-acid. Glad you caught that.

Carol

Sugar, like salt can be used to prevent spoiling. This is why most jams and jellies seem to last forever without spoiling. Things like 'candied citron' are fruits that are left in sugar to help them remain stable without spoiling. High acid also helps to preserve foods. A few other ways are to brine cure, salt cure, dry (dehydrate), sulfur treat, and even nitrates for curing meats. Then we get down to smoking some foods.. Low/no sugar jams usually spoil if they are left out too long, even if they contain a high acid.

Salt tightens water so it is unavailable to bacteria and fungi, sugar do the same.
You can control bacteria by keeping Ph at 4,5or lower, lowering water activity (salt sugar),