ARS | Publication request: Characterization of lipids and their oxidation products in baked or fried breaded shrimp products

Submitted to: Open Food Science Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 23, 2008
Publication Date: January 5, 2009
Citation: Dean, L.L., Fenner, G.P., Boyd, L.C. 2009. Characterization of lipids and their oxidation products in baked or fried breaded shrimp products. Open Food Science Journal. 3:1-7.

Interpretive Summary: Commercial samples of frozen shrimp with breaded exteriors were tested when raw, baked and fried for cholesterol, plant sterols, and fatty acids (fat components) to look for changes that indicate these compounds were being degraded. It was found that cholesterol formed oxidation products. The plant sterols were found to have decreased due to the cooking, but no oxidation products could be found. The fatty acids in the cooking oil were degraded by heat. The results show that cholesterol is easily oxidized. Plant sterols oxides may not be so easily formed but they are degraded by heat.

Technical Abstract: Two breaded shrimp products were examined for the changes in cholesterol, phytosterols, and fatty acids that occurred during cooking. The products were analyzed by gas chromatography (GC) in the raw, baked, and fried states after separation into breading and shrimp components. Cholesterol, campesterol, stigmasterol, and '-sitosterol were quantified and the changes with different heat treatments were determined. Phytosterol concentrations increased in the products due to moisture loss and oil absorption by the breading. Oxidation products of cholesterol were found after cooking in the shrimp portions of both the baked and the fried samples using gas chromatography in tandem with mass spectroscopy (GC-MS). No phytosterol oxides were found after cooking. The frying oils showed oxidative losses of both phytosterols and polyunsaturated fatty acids.