title: Degradation kinetics of anthocyanin in blueberry juice during thermal treatment.
abstract: The kinetics of anthocyanin degradation in blueberry juice during thermal treatment at 40, 50, 60, 70, and 80 degrees C were investigated in the present study. Anthocyanin degradation was analyzed up to the level of 50% retention using a pH differential method. The degradation of anthocyanin at each temperature level followed a first-order kinetic model, and the values of half-life time (t(1/2)) at temperatures of 40, 50, 60, 70, and 80 degrees C were found to be 180.5, 42.3, 25.3, 8.6, and 5.1 h, respectively. The activation energy value of the degradation of the 8.9 degrees Brix blueberry juice during heating was 80.4 kJ.mol(-1). The thermodynamic functions of activation (DeltaG, DeltaH, and DeltaS) have been determined as central to understanding blueberry degradation.
authors.affiliation: Chemical Engineering Dept., Federal Univ. of Rio Grande do Sul (UFRGS), Rua Luiz Englert s/n - Porto Alegre/RS 90040-040, Brazil. carolpk@enq.ufrgs.br
authors.forename: Carolina Pereira
authors.initials: CP
authors.lastname: Kechinski
authors.forename: Pâmela Virgínia Ramos
authors.initials: PV
authors.lastname: Guimarães
authors.forename: Caciano Pelayo Zapata
authors.initials: CP
authors.lastname: Noreña
authors.forename: Isabel Cristina
authors.initials: IC
authors.lastname: Tessaro
authors.forename: Lígia Damasceno Ferreira
authors.initials: LD
authors.lastname: Marczak
mesh_terms: D000872:Anthocyanins / Q000032:analysis / Q000378:metabolism*; D001628:Beverages / Q000032:analysis*; D029798:Blueberry Plants / Q000378:metabolism*; D003296:Cooking / Q000379:methods*; D005519:Food Preservation / Q000379:methods; D006358:Hot Temperature; D007700:Kinetics; D013816:Thermodynamics
chemical_list: D000872:Anthocyanins