Sour grapes?

Went through one huge bunch of red seedless grapes.

I wonder how long it takes to get from the groves to my produce market, and
as long as they sit there, then get to my house... how long will they last
before going sour?!?

I'm not timid in any sense, just asking.

?

And I have had sour grapes off a wine vine. VERY bitter.

Andy