Questions about preserving things in vinegar

Years ago, I received as a gift a large bottle of vinegar, sealed with a cork and wax. I believe it came from BB&B.

Anyway, it contained a large quantity of peeled raw garlic cloves, some Italian red peppers, and slices of mango. Not only was it the best salad-dressing vinegar I have ever used, but the pickled garlic cloves were absolutely delicious, as were the peppers and mango. I want to try and make some.

Here are my questions: First, the vinegar seemed very mild. Is it possible it was done with rice vinegar? Is rice vinegar acidic enough to work? Or was it probably, say, white wine vinegar that was mellowed by the mangoes & etc.?

Second, how long would it have to sit before the garlic was soft? It wasn’t mooshy, but tender, and most of the bite gone out of it.

Third, obviously I would want to boil my jar and cork; but would I have to do anything else special other than put in the solids and pour the vinegar over it, by way of preserving it? (and sealing with wax.)

Thanks!

Rice vinegar would be fine. I substitute it a lot in cooking. The usual choice for a vinegar with fruit in it would be apple cider vinegar.

According to this site - Do be aware, however, that wine and rice vinegars contain protein that provides an excellent medium for bacterial growth, if not stored properly.

So maybe not. I must admit I usually use rice vinegar for chinese style pickles that are consumed the same day.