Effect on physico-thermal properties of Pantoa during sub-baric frying

Abstract

Pantoa is traditional dairy product of the Indian subcontinent. The physico-thermal properties of Pantoa during sub-baric frying were evaluated at varying temperatures. The Pantoa balls were fried at 115, 125 and 135 °C for 4, 6 and 8 min at 200 mm Hg vacuum. The average sphericity values of sub-baric fried Pantoa at 115, 125 and 135 oC were 0.921, 0.943 and 0.968, respectively. The rate of expansion of Pantoa increased with increase in sub-baric frying temperature. The Apparent density values decreased with increase in the frying temperatures. The thermal conductivity of Pantoa decreased as frying time and temperature increased from 0.354±0.015 W/mK to 0.169±0.020, 0.158±0.025 and 0.146±0.031 W/mK at 115, 125 and 135 oC, respectively. The thermal diffusivity had an increasing trend up to 270 s of sub-baric frying at 135 and 125 oC and reached higher value of 0.196±0.064 mm2/s and 0.186±0.067 mm2/s, respectively from the initial value of 0.105 mm2/s. The volumetric specific heat of Pantoa was decreased as its function of sub-baric frying temperature and time.