Changes in the flavan-3-ols, anthocyanins, and flavanols composition of cocoa beans of different Theobroma cacao L. groups affected by roasting conditions

Abstract

In the present study, the effect of roasting conditions on the individual flavan-3-ols, anthocyanins, and flavanols content of cocoa beans of five different Theobroma cacao L. groups was studied. The raw cocoa beans were roasted at four different temperatures (110, 120, 135, and 150 °C) and three different relative air humidities (0.3, 2.0, and 5.0 %). The great variations in the contents of both total and individual phenolic compounds among the different studied cocoa groups were observed. In general, the cocoa beans of the Forastero group from Brazil exhibited the highest content of individual flavan-3-ols, anthocyanins, and flavanols, while the samples of the Trinitario type from Papua New Guinea had the lowest polyphenols levels. Roasting significantly affected the profile and levels of the flavan-3-ols, anthocyanins, and flavanols in cocoa beans. The changes depended upon the different cocoa types evaluated and their processing conditions. A decrease in epicatechin, procyanidin B, procyanidin C1, both anthocyanins, and quercetin glycosides was observed in all of the five cocoa groups tested after roasting. This reduction coincided with the increase in catechin and quercetin contents in roasted cocoa beans from the five cocoa groups.