Ascertaining optimal ohmic-heating characteristics for preserving mango (Mangifera indica l.) pulp through analysis of physicochemical properties and hurdles effect

The present work investigated the effects of ohmic-heating characteristic parameters on mango pulp's biochemical and rheological properties. Various pulp concentrations were subjected to different voltage levels till the pasteurized temperature of 70-80°C was reached. The heating time decreased with an increase in voltage gradient for a particular pulp concentration but increased as the pulp concentration increased. But the electrical conductivities of the pulp increased with the increase in pulp concentration and temperature. The quality parameters and the sensory scores of the pulp were dependent on the voltage gradient and concentration of the pulp. The mango pulp at 10°Brix retained maximum phytochemicals and the highest sensory score of 8.41±0.43 on the exposure to 15 V/cm. The rheological properties analysis envisaged the non-Newtonian behavior of pulp. The storage stability of ohmic-heated and conventionally-heated pulp in the presence and absence of preservatives was analyzed using hurdle factors. The result indicated that the ohmic-heated pulp sample with a concentration of 10°Brix at the 20 V/cm voltage gradient and 75°C pulp temperature with preservative could be stored for 90 days, whereas the conventional-heated samples exceeded the FSSAI limits after 60 days confirming the preference for ohmic-heating to preserve mango pulp to the latter.