Premium
Changes in the lipids of cod during storage in ice
Author(s) -
Lovern J. A.,
Olley June,
Watson Helen A.
Publication year - 1959
Publication title -
journal of the science of food and agriculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.782
H-Index - 142
eISSN - 1097-0010
pISSN - 0022-5142
DOI - 10.1002/jsfa.2740100605
Subject(s) - sterol , hydrolysis , chemistry , cholesterol , lecithin , phosphatidic acid , composition (language) , biochemistry , food science , flesh , phospholipid , membrane , linguistics , philosophy
Cod were stored in crushed ice and the composition of the flesh lipids determined at intervals over a total period of about 8 weeks. The outstanding changes are hydrolysis of phospholipids with concomitant production of free fatty acids, and progressive esterification of free “cholesterol”. The former takes place without accumulation of such intermediates as lysophosphatides, phosphatidic acids or diglycerides, but there is evidence of some intermediate between free and esterified sterol. Lecithin and phosphatidyl ethanol‐amine are hydrolysed at the same rate. Initial rates of change are relatively low, becoming markedly greater after about 2 weeks, but virtually ceasing rather abruptly before complete conversion has occurred. After about 5 weeks, when some 70% of the phospholipids has been hydrolysed, there is no further breakdown, while the chemical composition of the phospholipids does not alter significantly at any time. The sterol transformations, as observed, are virtually over after 6 weeks, with 85% of the sterol in the esterified form, but it is uncertain whether the final sterol is cholesterol. The only definite destruction of lipid which occurred was of free fatty acids, in one experiment, after about 5 weeks. The possible contributions of non‐enzymic, autolytic and bacterial agencies to the over‐all effects have been briefly considered.