Beetroot Juice Extraction Using Pulsed Electric Field Combined With Mechanical Pressing
In this paper, simultaneous mechanical pressing and PEF treatment for beetroot juice extraction was
experimentally investigated and discussed. The experiments were carried out using the laboratory PEF treatment system,
operated at the electric field strength in the range from 2.5 to 5 kV/cm, the pulse duration of about 100 μs, the pulse
repetition time of about 10 ms, the pulse frequency of about 1 Hz, the PEF treatment time in the range from 10 – 20 min, the
constant pressure of about 3 bar, and the total time of mechanical expression up to 5 min for with and without PEF treatment.
In absence of the PEF treatment, the final juice yield for beetroot was not depended on the PEF treatment time. It was shown
that the PEF treatment before pressing results in higher juice yield of beetroot than only pressing. Increased in the electric
field strength resulted in increasing the juice yield of beetroot in narrow range. In case of pressing without PEF treatment,
the average juice yield of beetroot was found up to about 31 %. The maximum juice yield of beetroot was found up to 71 %
for the electric field strength of 3.75 kV/cm at the PEF treatment time of 15 min in pressing with PEF treatment. This results
evidence that PEF enhanced expression is promising for production of higher quality juices in food industry.
Keywords- Pulsed electric field, Extraction, Juice, Beetroot.