RESEARCH ON STABILITY AND ANTIOXIDANT ACTIVITY OF ACEROLA JUICE USING FREEZE CONCENTRATION AND EMULSION

Abstract

Acerola (Malpighia emarginata DC.) is one of the best sources of vitamin C and natural bioactive compounds. Concentrating and forming W/O emulsions containing acerola juice helps improve applicability and diversify food products. This study used freeze concentration and spontaneous emulsification methods. The number of concentration stages, the appropriate freezing times, and factors affecting emulsion properties, such as emulsifier ratio, concentrate ratio, and stirring speed, have been studied. Selected results from the previous experiment will be used consistently in the following experiments. The results showed suitable conditions for concentrating acerola juice were 3 stages of concentration with a freezing time of 24, 36, and 60 hours, respectively. W/O emulsion created from 40% concentrate and 10% PGPR in the oil phase, stirred at 700 rpm for 15 min, had high stability with a viscosity of 39.44 ± 0.58 mPas. The content of biologically active compounds such as TPC, TFC, and vitamin C was found to be 24.28 ± 0.26 mgGAE/g, 33.94 ± 1.84 mgQE/100 g, and 34.95 ± 0.74 mgAAE/g, respectively. Antioxidant capacity, determined by the DPPH free radical scavenging method, was 64.83 ± 1.07%. The research results indicated that the W/O emulsion containing acerola juice produced by the concentration and spontaneous emulsification method was stable and contains high levels of bioactive compounds, making it applicable in the food industry.