The hydrolysis of proanthocyanidins IO anthocyanidins in n-BuOH-HCI (95: 5) has been shown to bc an autotition, the y&i of anthocyanidin being critically dependent on traa me&ion impurities. Rep&u&k yields of anthocyanidin may be achieved if iron (III) salts are added to the reaction malium. and a standard method ofanalysis of proanthocyanidins based on use of an n-BuOH-HCI-Fel" mixture is given. The ratio of absorbance maxima of the cyanidin (550 nm) produced to that near 280 nm for the original procyanidin polymer solution was 5 3.5.

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A rapid method for the extraction, separation and quantification of the geometric isomers of lycopene and beta-carotene from tomato fruit is described. Carotenoids in tomato were separated and eluted using a reversed-phase HPLC with a C30 column and a mobile phase consisting of methyl-t-butyl ether, methanol and ethyl acetate. The system provided sharp resolution of cis- and trans-isomers of lycopene within approximately 23 min in contrast to the longer and more complex gradient procedures required by previously described methods. Experiments indicate that the stability of extracts of fresh tomato may be improved if stored at -20 degrees C, and that the presence of the antioxidant BHA has no apparent effect on stability.