Fatty acids and cholesterol oxidation in salted and dried shrimp

The aim of this work was to evaluate the occurrence of cholesterol oxidation products and to analyze the lipidic profile in salted-dried shrimp. Fifty samples of salted-dried shrimp were evaluated, and the cholesterol oxides (7 beta-OH, 7 alpha-OH, 7-Keto and 25-OH) were quantified by high-performance liquid chromatography. The cholesterol oxides: 7 beta-OH (34.63-72.56 mu g/g), 7 alpha-OH (5.02-12.12 mu g/g), 7-Keto (7.44-32.68 mu g/g) and 25-OH (2.37-22.88 mu g/g) were determined in all samples analyzed. Regarding to the total cholesterol content and the average thiobarbituric acid reactive substances (TBARS) content, the results ranged from 73.88 to 247.69 mg/100 g, and 0.02 to 1.30 mgMA/kg, respectively. The fatty acids profile was: 27.48% saturated, 43.90% monounsaturated and 28.61% polyunsaturated. The presence of cholesterol oxidation products and the values of TBARS indicate the degree of oxidation of this product, which was probably initiated by inadequate conditions of processing and storage. (c) 2005 Elsevier Ltd. All rights reserved.