Abstract

• In addition to liquid foods and semi-solid foods, agricultural products such as vegetables and fruits are currently being dried and distributed to food processing companies. The purpose of such food drying processes is not only to reduce the volume and weight of the products but also to improve the product stability (shelf- life) whereas the product quality must be maintained during and after drying. For drying of vegetables and fruits, freeze-drying (FD) is known to be a good method, by which product shrinkage is eliminated or minimized, and a near-perfect preservation results are expected. The aim of this study was to investigate the production of freeze-dried papaya and watermelon in the form of powder that can be used as a natural alternative to synthetic additives used in food products such as pudding, beverages, jam, jelly and sauces for improving their flavor and aroma. To evaluate the characteristics of freeze-dried fruit powder, physico-chemical characteristics such as moisture, total fiber, ash, protein, vitamin C, total soluble solids, pH and rehydration ratio were determined. The phytochemical investigation and chemical analysis of fresh fruits were also carried out. The analysis of major and traces elements in freeze-dried papaya and watermelon were determined by using X-ray Fluorescence Spectrometry (XRF).