Kautkar et al.

Table 5. Relation of temperature (T) at different time (t) and voltage gradients

Salt Level

5 V/cm

9 V/cm

13 V/cm

(%)

T

R

2

T

R 2

T

R 2

0

0.051 t +29.96 0.999 0.116 t +27.95 0.992 0.179 t +27.72

0.979

0.5

0.074 t +27.64 0.985 0.163 t +26.44 0.972 0.261 t + 25.98

0.962

1

0.093 t +27.66 0.987 0.224 t +24.96 0.938 0.371 t +26.55

0.969

1.5

0.117 t +28.07 0.992 0.281 t +26.96 0.978 0.574 t +26.26

0.975

2

0.148 t +27.89 0.985 0.406 t +26.78 0.966 0.743 t +25.63

0.953

change of temperature and electrical conductivity

was higher for higher salt addition at all voltage

gradients applied. Bubbling occurred above 70˚C

especially at higher voltage gradients and when salt

is added. The mathematical models taking the system

performance coefficients into account can be used to

predict accurately the ohmic heating times of ginger

paste. The determination of electrical conductivity

changes and system performance coefficients during

ohmic heating are important in the design of ohmic

Figure 5: Time of heating variation with temperature and salt

heaters.

level at 13 v/cm

Acknowledgements

The authors wishes to acknowledge ICAR for

providing fellowship during the research work and

Dr. R. K. Pandey, Dr. Anupama Singh and Dr. P. K.

Omre for suggestions during the research work.

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Figure 6. Ohmic heating behavior of ginger paste

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the combinations of voltage gradients. The rate of

26