| Popis: |
The effect of three different drying temperatures (60, 70, 80 ºC) was evaluated in effective diffusivity, colorimetric parameters, antioxidant activity, and betalain content of pulp (P) and mesocarp (M) of pitaya (Hylocereus costaricensis). The increase in drying temperatures had a direct influence on drying constants, showing the drying rate is faster when drying temperature of 80 ºC was used. Modified Page model described the drying behaviour of pitaya pulp and mesocarp. In the colorimetric parameters, the higher drying temperatures decreased the luminosity and the reddish tonality and increased the color saturation. The drying promoted a concentration of antioxidants compounds in relation to in natura samples. The betalain content decreased in the pulp and it was maintained in the mescocarp samples, while the total phenolic compounds and the antioxidant activity increased in both pitaya parts when higher temperatures were used in the drying process. For these reasons the temperature of 60 ºC was indicating the most appropriate temperature for temperature for pitaya pulp end mesocarp drying process. |
