tim, I don't think I'd reduce the vinegar. I haven't pickled loquats, but in checking recipes literally all I see including one from cefresno.ucdavis.edu use a ratio of no less than equal parts water to vinegar. I see no exceptions - and the .edu recipes are normally considered written to be safe.

The minimum approved ratio of vinegar to water is 1:1 - 50/50 so no, reducing the vinegar can cause safety issues during storage. Problem is the water in the fruit already dilutes the vinegar more and the pH rises over time.

Same thing with the apples. The water in the apples have already diluted the vinegar in the original brine. By adding fresh apples to the already diluted brine you are dropping the pH to a possible risky level.

Dave

Thank you

I guess I can separate and dilute just before eating.