Influence of pretreatment with ethanol and drying temperature on physicochemical and antioxidant properties of white and red pulp pitayas dried in foam mat

Pitaya is a perishable fruit with a high content of bioactive compounds. This study aimed to evaluate the influence of ethanol pretreatment (95% dripped on the surface of the foam at a rate of 0.05 mL.cm(-2)) and temperature (50 and 70 degrees C) on moisture content, water activity, solubility, color, ascorbic acid, antioxidant capacity (DPPH and FRAP) e betanin and betaxanthin retention of white and red pitaya powdered pulps and to determine an optimal process condition. Pretreatment and higher temperature resulted in increased solubility and antioxidant capacity of powdered pulps. The total color difference was influenced by pretreatment and drying temperature, but in different ways according to the variety. In the pretreated red pulp powders, 70 degrees C resulted in higher retention of ascorbic acid and 50 degrees C resulted in increased retention of betanins and betaxanthins. The optimal treatment for white and red pulps was the use of pretreatment and a temperature of 70 degrees C.

Automated summary

This study evaluated the effects of ethanol pretreatment and temperature on the properties of powdered pitaya pulps and determined the optimal processing conditions. Pretreatment and higher temperature increased solubility and antioxidant capacity of the pulps, with different temperature effects on different varieties.