Evaluating Monolayer Moisture Content of Rubber Seed using BET and GAB Sorption Equations

In this investigation, the monolayer moisture content of rubber seed was evaluated from Brunauer, Emmett and Teller (BET) and Guggenheim-Anderson-de Boer (GAB) sorption equations at 250C for assessment of its storage stability and accessibility. The equilibrium moisture contents of rubber seed were found to vary from 10.01 to 17.37% (d.b.) after two months exposure on bare floor at 250C. The monolayer moisture contents were found to be 16.47 % (d.b.) and 11.75 % (d.b.) using BET and GAB sorption equations in the range of water applicability of 0.2-0.4 and 0.3-0.9, respectively. All the equilibrium moisture contents, with the exception of the initial, evaluated from the GAB equation were slightly higher than the monolayer value. The level of deterioration of the stored seeds, as indicated by mould growth, increased with increase in moisture content. Hence, it is better to store rubber seeds at moisture content slightly above their corresponding monolayer value for extending their shelf lives.