MATERIALS & METHODS
Fresh fruits (guava, mango, papaya and pineapple) were purchased from local market in the city of São Carlos-SP, Brazil. The cores of the mango and pineapple samples and the seeds of papaya were removed. The fruits were cut into slices of 5 mm thickness and placed in a circular tray with a diameter of 125 mm and height of 15 mm and subsequently were frozen in liquid N2. The frozen fruits were dehydrated in a laboratorial scale freeze-dryer, manufactured by Edwards, L4KR model.