Electroanalysis of soluble solid content in orange juice at intermediate frequency

摘要

A measurement method was applied to evaluate electrical response of orange juice at intermediate frequency by two alternating magnetic fluxes. Measurement of output voltages and λ-values (ratio of excitation voltage to output voltage) at different potential points in juice coils under varying excitation voltage, frequency, and temperature were conducted. The finding indicated that electrical potential differences in the in-phase or reverse-phase system could reflect physicochemical properties of thesamples. The trends of output voltage on the juice coil at 0–10 V and 20–100 kHz and its voltage distribution were accord with Ohm’s law through evaluating their equivalent circuits. The highest linear correlation between the output voltages and soluble solid content (SSC) of orange juice was obtained at 5 V, 20 kHz and 30 °C (0.837≤R2≤0.922). The measurement system and its procedure would contribute to the rapid evaluation of SSC in orange juice or other liquid food.