The degradation rates of anthocyanins are dependent on pigment
concentration being slower with higher concentration
(Merin etal., 1987). They further added that the destruction color
during heating is much more rapid when oxygen is present and
hydrolysis of the aglycon-sugar bond (position, 3) can occur at
100 C (pH 2–4). Also, thermal degradation leads to the formation
of the chalcone and its subsequent yield of several degradation
products that condense to form complex brown polymeric
compounds known as melanoid in pigments (Piffaut et al., 1994).