The strong pungent taste increases in sea urchin gonads during freezing storage for several months, and such off-flavor reduces its quality as food.
Pungent components in sea urchin, Strongylocentrotus intermedius, gonad, which was frozen at -13±5°C for 6 months, were isolated and identified.
1) Three pungent fractions, volatile neutral carbonyls, nonvolatile neutral carbonyls and keto carboxylic acids, were obtained from the frozen gonad.
2) Acetaldehyde, crotonaldehyde and n-valeraldehyde (or iso-valeraldehyde) were contained in the volatile neutral carbonyl fraction, aldol and crotonaldehyde in the nonvolatile carbonyl fraction, and pyruvic acid, α-keto butyric acid and α-keto iso-caproic acid in the keto carboxylic acid fraction.