Does pickle relish spoil

Yes. All organic matter spoils at one point or another, but pickles last much longer than many foods because of the fermentation process. Pickles are simply cucumbers that have been placed in a solution or salt brine solution in large, uncovered vats. They are left to ferment from one to three months then salt is gradually added to complete the process. Fermenting pickles encourages the growth of helpful bacteria, which prevents the growth of microorganisms that cause decay.