Abstract: In order to improve the stability of pectin-protein-phenolics complex in cloudy apple juice, a model system was made by dissolving catechin, gliadin and apple pectin in water. The effects of relative molecular mass, degree of esterification (DE) of pectin and pH of the system on the stability of the ternary complex, evaluated based on turbidity retention rate were studied by one-factor-at-a-time and orthogonal array design methods. Results showed that as the relative molecular mass and DE of pectin and the pH of the system increased, turbidity retention rate initially increased and then decreased. Maximum turbidity retention rate was achieved by adding pectin with relative molecular mass of 84700 and DE of 62.95% and adjusting the pH of the system at 3.7.

Key words: pectin-protein-catechin, cloud stability, model system