Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2435416 | International Dairy Journal | 2007 | 9 Pages |
The kinetics of colour and fluorescence development were studied in aqueous systems containing whole milk powder (WMP) and sucrose (S) at three WMP/S ratios (R=0.30, 0.68, 1.06) and three temperatures (T=105, 122.5, 140 °C). At each testing time, the colour parameters Kubelka-Munk index (K/S), lightness (L), optical density (OD), absorption coefficient (K), dominant wavelength (DWL) and fluorescence (F) were determined. F and 100/L were the most appropriate parameters to study non-enzymatic browning in concentrated milk systems. Adequate models (r2>0.96) developed to analyse the effect of T and R on the rate constants, showed that colour parameters and their kinetic coefficients were mainly affected by temperature. The influence of R was more relevant at high temperatures. The activation energies and Q10 values obtained for K/S, 100/L, F and OD were in the range 81–159 kJ mol−1 and 1.8–3.8, respectively. F and reflectance properties showed different dependence on temperature and R, reflecting that although related, they do not have the same origin and significance.