A SIMPLIFIED ALTERNATIVE TO THE AOAC OFFICIAL METHOD FOR CHOLESTEROL IN MULTICOMPONENT FOODS

An AOAC official method for quantitating cholesterol in multicomponent foods, which was first published in the 13th edition of the Official Methods of Analysis, is rarely used. The method includes so many opera tions and manipulations-all described in excruciating detail-that most laboratories shun it altogether. Intent on finding an alternative, la boratories have developed their own methods for specific foods. As a r esult, new methods have proliferated, but still no practical method ha s been developed for the broader categories of multicomponent foods. T he aim of AOAC, which is to promote greater accuracy and uniformity of analytical results primarily through collaborative testing, has not b een well served under these circumstances. A different approach guided the work reported in the present paper. This approach was directed to ward updating and dramatically simplifying the existing AOAC official method. The method's chloroform-methanol-water mixed-solvent extractio n is preserved; however, all the remaining steps have been streamlined , updated, or eliminated by using newer technology. Cholesterol is qua ntitated with highly specific capillary gas-liquid chromatography usin g the internal standardization technique. The lipid extract is prepare d for the chromatography step by a brief saponification carried out in a culture tube. The resulting method has been validated by using Stan dard Reference Materials and the standard addition method. Because a s implified method is now available for quantitating cholesterol in the lipid extracts, the expectation is that more attention can be given to the development of improved and efficient extraction methods. This st ep remains as the central difficulty in any number of methods of analy sis for lipid analytes.