RESUMEN
In this research, the co-pigmentation reactions between black cherry plum (Prunus cerasifera Ehrh. cv. Pissardii Nigra) anthocyanins and caffeic, gallic, 4-hydroxybenzoic, malic, and tannic acids with different concentrations (0, 120, 240, 480, and 960 mg L-1) at various temperatures (20, 40, 60, 80, and 100°C) were investigated at pH 3.5. The strongest immediate co-pigmentations resulted at 960 mg L-1, being significantly highest using tannic acid at all temperatures. In addition, the anthocyanin stability and the brown polymeric color formation were investigated in the presence of different concentrations of sucrose sweetener (0, 30, and 60%) and different pHs (2 and 3) in the range of 0-60 h. Also, the amount of furfural was measured in the presence of 0% and 30% sucrose concentrations at pH 2 after 20 h at 90°C by HPLC (high-performance liquid chromatography), and the most polymeric color formation was observed in the concentration of 60% sucrose at pH 2 after 60 h.
RESUMEN
The co-pigmentation reactions involving anthocyanins of sour cherry (Prunus cerasusL.) were investigated with tannic, caffeic, 4-hydroxybenzoic, gallic, and malic acids at pH 3.5. The influence of the co-pigments with different concentrations (120, 240, 480, and 960 mg/L), and temperatures (20, 40, 60, 80 and 100 â), on the co-pigmentation effects, stoichiometric ratio (n), the equilibrium constant (K) and thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were determined.The strongest immediate co-pigmentation reactions were observed at 960 mg/L, being significantly highest using tannic acid; also,the greatest bathochromic and hyperchromic effects were reasonable for itsn,K, and ΔG° values of 0.64, 56.55, and -10.00 kJ/mol, respectively. Furthermore, tannic and caffeic acids, with the highest negative values ofΔH°(-11.74 kJ/mol) andΔS°(-8.08 J/K.mol) led to the most excellent stability at 100 â.The presence of anthocyanins in the sour cherry extract was confirmed with the Fourier-transform infrared spectroscopy technique.