Sorption isotherms for oat flakes (Avena sativa L.)

Abstract

Moisture sorption isotherms of oat flakes were determined at temperatures of 5, 25 and 37°C, using a gravimetric technique in an a w range of between 0.107 and 0.855. These curves were modeled using six equations commonly applied in food. The quality of the fit was assessed with the regression coefficient (r²) and the mean relative percentage error (MRPE). The best fit were obtained with the Caurie model with r² of 0.996, 0.901 and 0.870, and MRPE of 7.190, 17.878 and 16.206, at 5, 25 and 37°C, respectively. The equilibrium moisture presented a dependence on temperature in the studied a w range, as did the security moisture (X S). These results suggest that the recommended storage conditions of oat flakes include: a relative air humidity of 50% between 5 and 25°C and of 38% up to 37°C.

Keywords

• actividad acuosa
• simulación
• modelos de difusión
• almacenamiento