Effect of encapsulation on stability of anthocyanins and chlorogenic acid isomers in aronia during in vitro digestion and their transformation in a model system.

Aronia extract was encapsulated with maltodextrin (MD) or MD plus carboxymethyl cellulose, gum Arabic, or xanthan gum and digested under simulated conditions. The retention of anthocyanins was higher (75 %) in encapsulated aronia as compared to non-encapsulated one (58 %). Cryptochlorogenic acid significantly increased after in vitro digestion, whereas neochlorogenic acid and chlorogenic acid decreased. The increase of cryptochlorogenic acid was about two-fold higher in non-encapsulated aronia than encapsulated aronia. In a model system, cyanidin 3-galactoside and chlorogenic acid were separately digested under simulated conditions. Cyanidin 3-galactoside-CHO adduct (m/z 640) was firstly observed in the digested cyanidin 3-galactoside solution, suggesting that degradation products of anthocyanins bind to intact anthocyanins. In a separate study, cryptochlorogenic acid increased as much as chlorogenic acid decreased, indicating that chlorogenic acid can be transformed into cryptochlorogenic acid during digestion. The results show that encapsulation lowered molecular transformations of anthocyanins and chlorogenic acid during in vitro digestion.