DE-ESTERIFICATION OF CHLOROPHYLLS IN OLIVES BY ACTIVATION OF CHLOROPHYLLASE

The physicochemical conditions favoring the action of chlorophyllase i n olive fruit itself have been investigated. Different temperatures an d aqueous incubation media that contained acetone were tested. The hig hest levels of chlorphyllase activation in whole fruits (without extra ction of the enzyme) were achieved by heating the fruits at 50 degrees C in a buffer (pH 8.5)-acetone (1:1) mixture. A study of the effect o f pH on chlorophyllase activation in the fruit itself showed a maximum of activity at pH 7.5 and another fictitious maximum at pH 4.5. This second maximum may have been caused by a change in the composition of the substrate mixture as a function of the pH. The study highlights th e activation of chlorphyllase in the olive in the processes used for o btaining virgin olive oil and green table olives.