Influence of ultra-sonication on stability and physicochemical properties of coconut milk

Abstract

The impact of ultra-sonication (20 KHz) on stability, rheological and physicochemical properties of coconut milk was studied. The coconut milk (10 % fat) was sonicated at 20 KHz for 5, 10 and 15 min. The emulsion stability index (ESI) of coconut milk was increased due to sonication treatment with respect to treatment time and the maximum value of ESI was 36.15 min at 15 min treatment time. It was observed that the sonication treatment had synergetic effect on physicochemical properties such TSS, protein, FFA and viscosity. All the samples exhibited pseudoplastic behaviour with an average flow behaviour index (n) and consistency coefficient (K) of 0.193 and 2.682 Pa respectively. Among the power law and Bingham model, Bingham model showed higher correlation coefficient (R2 = 0.983). The microstructure analysis revealed that longer exposure of sonication time improved the particle size reduction due to cavitation effect.