GLC method has been developed for the quantitation of ammonium glycyrrhizinate as the aglycone, glycyrrhetic acid. The aglycone is freed from the sugar moiety in a dioxanewater mixture, using a well established acid hydrolysis procedure. The hydrolysate is extracted with chloroform, an aliquot is dried on a steam bath, and the residue is treated with pyridine - trimethylchlorosilane - N,0 - bis (trimethylsilyl)acetamide reagent. The reacted product and internal standard are then chromatographed on a column of 1.5% OV-1 on Gas Chrom Q. Recoveries from both water and sodas containing caramel averaged 87%.

The detection of C6 to C28 fatty acids is possible when their methyl esters are concentrated by urea fractionation so that esters with similar gas chromatographic retention times are in different fractions. By modified programmed temperature gas chromatographic techniques, it is possible to detect and estimate fatty acids present in trace amounts (0.1 to 0.001%) in palm kernel, shea nut, and illipe oils. The odd and even chain length saturated fatty acids from C6 to C28 were detected. The odd and even chain length mono-unsaturates from C14 to C24 and the even chain length dienes from C14 to C24 were detected

This proposed urea fractionation procedure concentrates esters with similar GLC retention times in separate fractions. GLC peaks of esters present in cocoa butter oil in trace amounts (0.001–0.1%), which are normally hidden under major peaks, can then be detected. By modified programmed temperature GLC techniques, it is possible to detect the short and long chain length fatty acids present in cocoa butter oil. The odd and even chain length saturated acids from C10 to C28, mono-unsaturates C16 to C24, branched acids C16 to C24, and linoleic and linolenic acids were detected.

A collaborative study was conducted comparing the AOAC methods (12.022 Method I and 12.023 Method II) for the determination of fat in cacao products with the OICC Soxhlet method and a rapid refractometric method. Six samples of cacao products (breakfast cocoa, vegetable fat coating, cacao nibs, milk chocolate, sweet chocolate, and chocolate liquor) were analyzed by 7 collaborators. Results indicate that the OICC method gives better precision and somewhat lower results than the AOAC method. It is recommended (1) that the OICC method as presented, using a final HC1 concentration of 4N in the digestion step, be adopted as official first action to replace 12.023 Method II, which will be deleted official final action by suspension of the rules; (2) that study be continued to accumulate data needed to correlate the results of the analysis of cacao products by the OICC method and 12.022 Method I; and (3) that 12.022 be qualified by a statement “(Not applicable to cacao nibs unless finely ground)”.

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