Orange juice cloud stability and the influence of calcium and hesperidin

Abstract

The clarification mechanisms of citrus juice cloud were evaluated in fresh juice and orange juice serum model systems. Ammonium oxalate (AO) was added to fresh juice at pH 4.0 and 5.5. Only juice at pH 4.0 without AO clarified over the three week study. In a model orange juice serum (OJS), the addition of hesperidin and protein (heated and unheated citrus protein and soy protein) showed that hesperidin interacted with protein. The % transmittance of OJS remained the same, and the protein controls were similar to results at lower hesperidin concentrations (<0.05 mg/ml). Higher concentrations of hesperidin (1.0-0.1 mg/ml) increased in turbidity in the presence of protein. Particle size tended to increase for heated and unheated citrus protein with hesperidin, but hesperidin or protein had little effect on particle size. Changes in particle size and cloud characteristics suggest non-electrostatic, non-covalent interactions are involved in cloud interactions and stability.