Concentrated coconut milk (CCM), a raw material from coconut products, is extremely unstable because of its high oil content (>30%). In this study, three model emulsions—primary emulsions stabilized by coconut proteins only, secondary emulsions stabilized by the conjugation of sugar beet pectin (SBP) and coconut protein, and laccase-treated secondary emulsions—were prepared to investigate the effects of different factors (coconut proteins, coconut proteins + SBP, laccase-treated emulsions) on the stability of model emulsions and the application of this method to real CCM. The stability of the emulsions was evaluated based on their interfacial tension, zeta potential, particle size distribution, rheological properties, and the assembly formation of SBP and coconut protein at the oil–water interface. Results showed that addition of SBP or laccase can increase the viscosity and reduce the interfacial tension of the emulsion, and the effect was concentration dependent. Zeta potential of the emulsion decreased with the increase of protein (from −16 to −32 mV) and addition of SBP (from −32 to −46 mV), and it was reduced when laccase was added (from −9.5 to −6.0 mV). The secondary emulsion exhibited the narrowest particle size distribution (from 0.1 to 20 μm); however, laccase-catalyzed secondary emulsions showed the best storage stability and no layering when the laccase content reached 10 U/100 g. Confocal laser scanning microscopy (CLSM) revealed that protein was adsorbed on the oil–water interface and SBP distributed in the continuous phase could undergo oxidative crosslinking by laccase. These results show that the stability of the concentrated emulsion can be effectively improved by adding SBP and laccase.

In this study, the quality of matured coconut water was improved through fermentation with Saccharomyces cerevisiae D254. During fermentation, the kinetic models of yeast growth, alcohol production, and sugar consumption were established based on logistic and Leudeking–Piret equations. Fructose, glucose, sucrose, total phenolic content, and antioxidant capacity (FRAP and ABTS values) were measured consecutively during fermentation. Results showed that R2 for the three models of yeast growth, alcohol production, and sugar consumption were 0.9772, 0.9983, and 0.9887, respectively. Total phenolic and antioxidant assays showed a similar evolution during fermentation, with a rapid increase in exponential phase and an unchanged trend in stationary phase. Moreover, total phenolic and the two antioxidant capacity methods were highly positively correlated. Pyruvic, lactic, citric, and succinic acids were the main organic acids in coconut water after fermentation.