Cholesterol Oxidation is Increased and PUFA Decreased by Frozen Storage and Grilling of Atlantic Hake Fillets (Merluccius hubbsi)

Fatty acid contents evolution and cholesterol oxides formation in Brazilian sardines (Sardinella brasiliensis) as a result of frozen storage followed by grilling

“…Frozen storage in sardines produced a considerable decrease in the cholesterol contents, and these changes after processing could be attributed to oxidative processes. Similar results were observed in hake samples (Saldanha & Bragagnolo, 2007) submitted to the freezing in the same conditions.…”

“…Similar results were found in previous studies in grilled sardines (Garcı´a-Arias et al, 2003a) and hake (Saldanha & Bragagnolo, 2007). However, unsaturated fatty acids are far more heat-labile, and losses varied from 14% to 18% in monounsaturated fatty acids (MUFA); and 18% to 24% in PUFA contents.…”

“…During frozen storage a significant increase was found in the fat content (Po0.02). However, such apparently anomalous behavior has been described by other works (Be´ltran & Moral, 1990;Be´ltran & Moral, 1991;Garcı´a-Arias et al, 2003a;Jime´nez-Colmenero, 1979;Saldanha & Bragagnolo, 2007;Wood, Hintz, & Salwin, 1968) in frozen fish, and indicates that the extractability of the lipids may be affected by the changes of protein-lipid complexes in the fish tissues during storage, what results in a increase of the lipids. According to Jittrepotch, Ushio, and Ohshima (2006), the amount of the extracted lipids in sardine samples tended to increase slightly during few days of refrigerate storage.…”

Oxysterols and mechanisms of apoptotic signaling: implications in the pathology of degenerative diseases☆

“…Moderate levels of oxysterols can occur in foods, most notably milk powders, meat and meat products (including fish), cheese, eggs and egg products [7][8][9][10][11][12][13]. During processing, preparation and storage, these foods can be exposed to heat, air, light or radiation [14].…”

Sample preparation: A critical step in the analysis of cholesterol oxidation products

“…Direct saponification of the food matrix, without prior lipid isolation, is a viable option for sample preparation (Mariutti, Nogueira, & Bragagnolo, 2008;Mazalli, Sawaya, Eberlin, & Bragagnolo 2006;Saldanha, Benassi, & Bragagnolo, 2008;Saldanha & Bragagnolo, 2007;Saldanha et al 2006). In a study by Saldanha et al (2006), sample preparation was carried out using direct saponification, followed by extraction of the unsaponifiable material.…”