Effect of high hydrostatic pressure pretreatment on drying kinetics, antioxidant activity, firmness and microstructure of Aloe Vera (Aloe Barbadensis Miller) gel

ANTONIO VEGA-GÁLVEZ; ELSA URIBE; MARIO PEREZ; GIPSY TABILO-MUNIZAGA; JUDITH VERGARA; PURIFICACIÓN GARCIA-SEGOVIA; ELENA LARA; KARINA DI SCALA

LEBENSMITTEL-WISSENSCHAFT UND-TECHNOLOGIE-FOOD SCIENCE AND TECHNOLOGY

ELSEVIER SCIENCE BV

Año: 2011 vol. 44 p. 384 - 391

0023-6438

The effect of High Hydrostatic Pressure (HHP) and other pretreatments on the drying kinetics, antioxidant activity, firmness and microstructure of A. vera gel was investigated during convective drying at 70 ºC. The pretreatments analyzed were high hydrostatic pressure, blanching, enzymatic and microwaves. Simulation of drying curves was studied through the application of several mathematical models such as Newton, Henderson and Pabis, Page, Modified Page, Wang and Singh, and Weibull. Among them, the Weibull model provided the best fit for the experimental data. All pretreatments increased the water diffusion coefficient compared to the control sample. Microwaves followed by HHP presented the fastest drying rates. All pretreatments modified the microstructure and hence the texture of the product. HHP and microwaves increased firmness while blanching and enzymatic treatments produced a softer final product. Blanching, microwaves and HHP enhanced A. vera antioxidant activity. However, the HHP pretreated samples showed the highest antioxidant activity compared to the rest. Based on these results, HHP together with convective drying offers the chance of producing dried aloe with high antioxidant attributes.