autoxidation
Spontaneous oxygen reaction
Autoxidation is oxidation that occurs spontaneously when a substance is exposed to air at ordinary temperatures.
Fats and oils undergo autoxidation, turning rancid over time.
Rubber degrades through autoxidation, becoming brittle and cracked.
The process is a slow chain reaction involving oxygen from the atmosphere: Antioxidants are added to prevent autoxidation.
Oxidative chain reaction in lipids
- superoxideCharged oxygen radical
- initiationFormal admission ceremony
- propagationAct of spreading widely
- terminationAct of ending something
lipids · unsaturated · kinetics · catalysis · reactivity · antioxidants · stabilizers · inhibitors
Unintended unpleasant tastes
- staleNo longer fresh
- rancidDecomposed fat's quality
- spoiledRuined or overindulged
- taintedContaminated, made impure
aldehydes · ketones · fishy · warmed-over · reversion · tallowy · painty · shelf-life
Prone to snapping
- crackingBreaking without separating completely
- yellowingBecoming pale gold-brown
- chalkingApplying calcium carbite stick
- embrittlementMaterial losing flexibility, gaining fragility
deterioration · weathering · crosslinking · plastics · elastomers · coatings · stabilizers
Spontaneous combustion from heat
- coalCombustible sedimentary rock
- haystacksPiled dried grasses
- exothermicReleasing energy as heat
- self-heatingProduces warmth independently
peroxidation
Oxidative chain reaction in lipids
- superoxideCharged oxygen radical
- initiationFormal admission ceremony
- propagationAct of spreading widely
termination · lipids · unsaturated · kinetics · catalysis · reactivity · antioxidants · stabilizers · inhibitors · phenols
off-flavors
Unintended unpleasant tastes
tainted · aldehydes · ketones · fishy · warmed-over · reversion · tallowy · painty · shelf-life · preservatives
brittleness
Prone to snapping
- crackingBreaking without separating completely
- yellowingBecoming pale gold-brown
- chalkingApplying calcium carbite stick
embrittlement · deterioration · weathering · crosslinking · plastics · elastomers · coatings · stabilizers
autoignition
Spontaneous combustion from heat
- coalCombustible sedimentary rock
- haystacksPiled dried grasses
- exothermicReleasing energy as heat
rusting
Metal oxidation process
- tarnishingOxidizing and losing shine
- patinaSurface film from aging
- pittingForming small cavities
electrochemical · anodic · cathodic · iron · copper · aluminum · steel