MICROWAVE-ASSISTED FOAM-MAT DRYING TECHNIQUE FOR PRESERVING THE PROPERTIES OF HONEYDEW MELON

Abstract

The paper presents a recent application of the fast nonconventional microwave heating a fruit (honeydew melon) for removing the high moisture content (above 90 %) in order to preserving its qualities. The fruit was prepared as a paste in which a foaming agent (egg white) and a foam stabilizer (carboxymethyl cellulose) were inserted for obtaining an expanded product, facilitating the removal of water. By drying and fast heating the fruit, the required conditions for its preservation are achieved, keeping ß-carotene and C-vitamin unchanged. The microwave heating parameters were: product temperature between 190-250 ºC, heating and drying time between 1.50-2.41 min, heating rate between 95.4-113.3 ºC/min, water amount removed by vaporization between 14.8-15.3 g and energy consumption for the water vaporization between 4-6.2 W/min.

Keywords

• foam-mat drying
• food preservation
• moisture
• microwave heating
• egg white
• carboxymethyl cellulose