Quick pickles are not fermented. Quick pickles are made from fresh fruits and vegetables. Vinegar, sugar and spices are added. Then the pickles are pasteurized. Pickled cucumbers don't require much introduction, glass jars filled with different cucumber types stand on shelves in each supermarket. Billions of hamburgers are sold every year by fast food franchises and they contain a slice of a pickle inside. Canned pickles are subsequently pasteurized which eliminates oxygen by creating a vacuum inside the jar. This prevents molds and yeasts from growing. It also destroys tissue softening enzymes which create soft pickles.
Quick pickling requires at least as much vinegar as other liquids. For pickling purpose brine, fruit or vegetable juice are all considered water and must be matched with an equal amount (or more) of vinegar. Acidity and the following pasteurizing step are the main safety precautions against pathogens so the amount of salt can now be decreased. According to USA standards, when the food is acidified to pH 4.6, the pathogenic bacteria spores cannot produce toxins.