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>Homemade salsas
>usually do not require vinegar; I think that commercial salsas have
>vinegar in order to increase the acidity of the product.

Correct. Increased acidity increases shelf life. For awhile here in the NY
area we could buy an excellent tasting salsa called Simpson's that only used
lime juice. Apparently he thought he had found a way to get it acidic enough
without vinegar. It is no longer on the market and he is out of business.

Restaurants here in NYC also frequently put vinegar in their fresh salsa.
Vinegar is very popular here, and they think their clientele likes it that way.

Don Wiss.