Kinetics of nonenzymatic browning in Cheddar cheese powder during storage

Nonenzymatic browning (NEB) in Cheddar cheese powder during storage was investigated in the water activity (a_w) and temperature ranges of 0.48-0.85 and 20-7 40C, respectively. The NEB obeyed zero-order reaction kinetics during storage. Activation energies and Q₁₀ values were in the range of 15.1-22.3 kcal/mole and 2.2-3.5, respectively. The NEB increased with increasing temperature and storage time. There was an a_w maxima at 0.63 for NEB at 20C. At 30 and 40C, NEB decreased with increasing a_w. A generalized NEB model for Cheddar cheese powder during storage was developed based on Arrhenius equation to describe NEB as a function of a_w and temperature. Powders stored at 20 and 30C were evaluated for quality aspects. Maximum storage stability was obtained in powders stored at a_w of 0.54 at 20C for five months based on an overall desirability score of 3.5 on a 7-point scale. The average score of fresh powders were 4.7 throughout the storage study 7.