Effects of Pulsed Electric Fields on the Quality of Orange Juice and Comparison with Heat Pasteurization

TLDR

The study evaluates pulsed electric field (PEF) treatment of orange juice versus conventional heat pasteurization to assess quality preservation. PEF was applied at 35 kV/cm for 59 µs, while heat pasteurization was performed at 94.6 °C for 30 s, and the effects on microbial load, enzyme activity, and physicochemical properties were measured. PEF-treated juice maintained higher vitamin C and flavor compound levels, exhibited lower browning, higher whiteness and hue angle, smaller particle size, and comparable Brix and pH relative to heat-pasteurized juice during 4 °C storage.

Abstract

Effects of pulsed electric fields (PEF) at 35 kV/cm for 59 micros on the quality of orange juice were investigated and compared with those of heat pasteurization at 94.6 degrees C for 30 s. The PEF treatment prevented the growth of microorganisms at 4, 22, and 37 degrees C for 112 days and inactivated 88% of pectin methyl esterase (PME) activity. The PEF-treated orange juice retained greater amounts of vitamin C and the five representative flavor compounds than the heat-pasteurized orange juice during storage at 4 degrees C (p < 0.05). The PEF-treated orange juice had lower browning index, higher whiteness (L), and higher hue angle (theta) values than the heat-pasteurized orange juice during storage at 4 degrees C (p < 0. 05). The PEF-treated orange juice had a smaller particle size than the heat-pasteurized orange juice (p < 0.05). degrees Brix and pH values were not significantly affected by processing methods (p > 0. 05).