Is it necessary to add alum to pickles to make them firm?
Alum is not necessary in pickles. As long as good quality ingredients and up-to-date procedures are used, don’t use it. You can use it for fermented cucumbers. It does not work with quick process pickles. Most recipes do not have alum as an ingredient. A safer method to make crisp pickles is soaking the cucumbers in ice water for 4 to 5 hours prior to pickling.
