Three two-parameter equations and one three-parameter equation were evaluated for goodness of fit of moisture content vs. water activity for 75 sorption isotherms representing fruit, vegetable and meat food products. It was found that the three-parameter Guggenheim-Anderson-de Boer (GAB) equation could represent more than 50% of the food isotherms with great accuracy. An equation having a mean relative deviation modulus of equal to or less than 5 was considered to represent a good fit to the sorption data. In all cases, the GAB equation described the fruit, vegetable and meat isotherms much better than the two paramèter equations. The mean relative deviation modulus and parameters for each of the equations are given in this paper.
|Original language||English (US)|
|Number of pages||7|
|Journal||LWT - Food Science and Technology|
|State||Published - Dec 1 1985|