Question

reasons for rancid in bread

Answer 1

Oxidation, irradiation, heat and moisture ..... these are the major factors .

Answer 2

oxidation,irradiation,heat are some of the major causes that induces fat to go rancid. It is found is cooking oil's,ghee,deep-fried foods etc. Refrigeration slows down the process rancidity as it prevents the exposure of food to oxygen and slows down the growth of microbes which cause oxidation.
Hope this answer help you.