Cholesterol oxidation products. Their occurrence and detection in our foodstuffs.

The structural similarity of cholesterol oxidation products (COP) to native cholesterol and their xenobiotic effects prompt researchers to study the long-term effects of the assimilation of these compounds into our tissues. COP are present in our food system. The level of exposure changes as our food products and our food choices alter. Therefore, the presence of COP in our food system has to be carefully monitored and their presence in processed foods minimized by optimizing processing and storage conditions. This review will briefly discuss the chemistry of some commonly-occurring COP and their biological significance. A more in-depth survey of the literature on the pitfalls of COP determination is included. It is the intention of the author to impress the readers that 'exogenous' COP can easily form during sample preparation. These artifacts will hinder our understanding of factors that promote COP formation in foods. The effects of heating, dehydrating, packaging and the presence of highly unsaturated lipids on the levels of COP in cholesterol-containing foods are evaluated to gauge the levels of exposure to different consumer groups.