Thermal and pH stability of yellow and red pigments produced by Thermomyces sp and Penicillium purpurogenum using response surface methodology
Poorniammal R, Prabhu S, AR Sakthi
The thermal stability of Yellow and red pigments produced by Thermomyces sp and Penicillium purpurogenum in submerged fermentation were analyzed. The pigments were evaluated under different temperature and pH conditions in glass bottles viz., 58.8º C to 101ºC and 3.5 to 10.4 respectively. The Central composite design involving the variables pH (X1) and temperature (X2), a response surface methodology for the stability of yellow and red standardized. Samples of yellow and red pigments were collected and submitted to measurement of the absorbance at 410 and 510 nm, respectively. The thermal degradation of the yellow and red pigments followed a first-order kinetic reaction. The response surface models and empirical results described the behavior of the responses of color degradation of the pigments, and the temperature dependence of the degradation constants.