Desorption isotherms of acerola fruits variety 'Okinawa'

Abstract

The cultivation of acerola in Brazil is growing. The acerola fruit is known to have several properties concur­rent with where it is grown. The determination of the water activity of biological products becomes essential in studies on drying, storage and packaging processes since the higher the water activity of a product, the higher the susceptibility to attacks by microorganisms. This study aimed to evaluate desorption isotherms of acerola fruits (Malpighia glabra L.) for the temperatures 30, 40 and 50 °C by the indirect static method. The experimental data were adjusted to the mathematical models BET, GAB, Halsey, and Oswin and Smith. Analyses of residues, coefficient of determination, relative standard deviation and estimated standard devia­tion were calculated for each adjusted model and used to evaluate the model that best adjusted to desorp­tion isotherms. Based on the results obtained, the Smith's model represented isotherms with a higher preci­sion for this variety of acerola.