Chocolate is a highly processed cocoa product known to be rich in flavonoids, compounds which have been long associated to both healthy and sensory properties. A multi-step process involving cocoa beans fermentation, drying, roasting, nib-grinding and refining, conching and tempering is implied in the production of chocolate.To our knowledge, scarce attention has been paid to the effect of conching on the procyanidins profile, on their polymerisation from monomers up to oligomers and polymers, as well as on the in vitro functional properties such as antiradical activity and reducing power. Two conching processes, characterized by different time/temperature combinations, a Long Time Conching (LTC) and a Short Time Conching (STC), were thus taken studied and the effect on flavan-3-ols monomers, on the degree of polymerization and on the in vitro functional properties of dark chocolates was studied. Procyanidin content was determined by HPLC analysis, while the total polyphenol index (TPI), the antiradical activity as well as the reducing power were evaluated by the reaction with the Folin–Ciocalteu reagent, the decolorization assays of the ABTS radical (TEAC) and the Ferric Reducing Antioxidant Power (FRAP) methods, respectively.The procyanidins content and profile were deeply affected by the different processing conditions: at the end of conching the STC-samples were characterized by a higher amount of monomers, compared to the LTC-ones which, in turn, resulted more polymerised as confirmed by the presence of P10 polymers. Both STC- and LTC conched products presented comparable TPI and FRAP values but products collected at different steps during the conching process, and in particular during LTC, showed a significant improvement of the radical scavenging properties. This result suggest the possibility to modulate the conching process in terms of time and temperature combination in order to improve the antioxidant activity of the final products.[...]
EFFECT OF CONCHING ON PROCYANIDINS AND FUNCTIONAL PROPERTIES OF CHOCOLATE
DI MATTIA, CARLA DANIELA;MARTUSCELLI, MARIA;SACCHETTI, Giampiero;MASTROCOLA, Dino;PITTIA, Paola
2013-01-01
Abstract
Chocolate is a highly processed cocoa product known to be rich in flavonoids, compounds which have been long associated to both healthy and sensory properties. A multi-step process involving cocoa beans fermentation, drying, roasting, nib-grinding and refining, conching and tempering is implied in the production of chocolate.To our knowledge, scarce attention has been paid to the effect of conching on the procyanidins profile, on their polymerisation from monomers up to oligomers and polymers, as well as on the in vitro functional properties such as antiradical activity and reducing power. Two conching processes, characterized by different time/temperature combinations, a Long Time Conching (LTC) and a Short Time Conching (STC), were thus taken studied and the effect on flavan-3-ols monomers, on the degree of polymerization and on the in vitro functional properties of dark chocolates was studied. Procyanidin content was determined by HPLC analysis, while the total polyphenol index (TPI), the antiradical activity as well as the reducing power were evaluated by the reaction with the Folin–Ciocalteu reagent, the decolorization assays of the ABTS radical (TEAC) and the Ferric Reducing Antioxidant Power (FRAP) methods, respectively.The procyanidins content and profile were deeply affected by the different processing conditions: at the end of conching the STC-samples were characterized by a higher amount of monomers, compared to the LTC-ones which, in turn, resulted more polymerised as confirmed by the presence of P10 polymers. Both STC- and LTC conched products presented comparable TPI and FRAP values but products collected at different steps during the conching process, and in particular during LTC, showed a significant improvement of the radical scavenging properties. This result suggest the possibility to modulate the conching process in terms of time and temperature combination in order to improve the antioxidant activity of the final products.[...]I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
