Well, since you found a lot of answers when you Google it, then it is safe. But for me, I don't want to use it anymore since it is already expired. Just to make it safe.. :-)

They may actually be "good" as in safe to consume, but I doubt they are "good" as in flavor due to such long extended shelf time. In home canning it is suggested we use what we can within a year. Think about it as storing food from one harvest to the next. Home canning has never been suggested for long-term food storage due to the processes and temperatures we use. Back-in-the-day, people stored their home canned food in much cooler temperatures than we do now, and they typically consumed most of it by spring.

Since these jars have probably been stored at room temperature (70-degrees F) or warmer in your pantry, that also shortens the shelf-life. The suggested storage temperature is 50-70-degrees F, with the cold end of that temperature window being the optimum choice.

Flavors are sure to have altered and changed since 1992, and the only way to know if a jar is "safe" (bacteria-free) is to have it tested in a lab. The sealing compound on the lids may have been compromised over time.

I'd suggest you follow the protocol for disposing of unsafe home canned foods (at the link below). Save and sterilize the jars to remind you of all the love and work your mother put into preserving food. I still have canning jars my mother used, but they are so old and brittle from all those years of being heat processed, I only use them for dry storage. Her jars would no longer be safe to use for canning, especially in a pressure canner, after all this time.

-Grainlady

Here is a link that might be useful: National Center for Home Food Preservation