Neighbor gave me some "pasteurized" hot sauce. It exploded with carbonation when I opened it at home.

As the title says.

Neighbor gave me some hot sauces he had made through fermenting at home. One was labeled Jalapeno / Pineapple. He told me that one was pasteurized and should be refrigerated after opening.

I took it home and went to open it to try. Bottle was pressurized and hissed when opening. I tasted some and found it to "taste" extremely carbonated. I screwed the lid back on, and when my partner went to open it again to try it for himself, the bottle contents foamed over and out of the bottle like a shook soda.

The other two fermented non-pasteurized hot sauces he gave us were not at all pressurized. What happened here, and is the hot sauce safe to continue eating?