Anchovy fish meal with an approximate uniform moisture content of 10%
was used for this study. Vapor adsorption isotherms were determined at
25 degrees C, 35 degrees C and 45 degrees C. The differential and int
egral thermodynamic properties were estimated using the Othmer method.
The isosteric heat or differential enthalpy, as a function of moistur
e content, showed a maximum value around 4.5 g of water/100 g d. s. Th
e heat of sorption increased gradually with an increase in sorbed wate
r until reaching its maximum value near the monolayer, and at a given
moisture content, decreasing with temperature. The molar entropy value
s obtained were high at low water contents and fell to a minimum near
the monolayer value.