Lexicon
Rancidity & oxidation
When oil goes old: spoilage through air, light and heat.
Definition
What happens when oil turns rancid
Rancidity is the spoilage of fat through oxidation. Oxygen, light and heat attack the fatty acids, producing an unpleasant smell, a bitter taste and unfavourable breakdown products.
Polyunsaturated oils like flaxseed oil turn rancid especially quickly, saturated oils are more stable.
In brief
- Spotting it: a scratchy, bitter, old smell and taste , then stop using it.
- Avoiding it: store cool, dark and well sealed, sensitive oils in the fridge.
- Freshness: use cold-pressed, omega-3-rich oils up promptly.
Related terms: Cold pressing, Omega fatty acids.
Source
- Rancidification , Wikipedia