Sorption isotherm study on vacuum and freeze-dried jamun pulp

Fruits play the most important role in nutrition. In India many underutilized medicinal fruits are available, and the most important fruit is jamun which is otherwise called black plum. Drying of underutilized jamun fruits helps in minimizing their post-harvest loss which occurs during harvesting season. The freeze-dried powder results with polar sites in molecular structure material which is occupied with water in wet conditions. During drying the molecules which were holding the water particles are attracted closely to each other. The study on sorption isotherms was carried out on the dried powder. These results gave a suitable model to fit sorption behaviour. The empirical equations frequently used to model drying kinetics are Newton, Henderson–Pabis, Page, Modified Page, Wang– Singh, Logarithmic, Two-Terms, Modified Henderson–Pabis and many mathematical models to describe the water sorption behaviour of foods. The GAB equation was fitted as the best fit for vacuum-dried jamun pulp powder stored at 27°C and 37°C.