1 oil and fat containing food items are flushed with nitrogen because nitrogen is an anti
oxidant which helps the food items to be preserved for a long time. it prevents the oxidation which keeps the food items tasty and fresh.
2.a-corrosion- it is the phenomena in which the upper layer of the metal get degraded due to the action of oxygen ,co2 or moisture
b-rancidity-it is the phenomena in which food items containing oil and fat when come in contact with air get oxidised and their taste and smel suddenly changes