Influence of Chemical Composition and Structure on Sorption Properties of Freeze-Dried Pumpkin

Abstract

The aim of this study was to investigate the influence of chemical composition and material structure on sorption properties of freeze-dried pumpkin. The chemical composition and material structure were changed by osmotic dehydration, blanching, freezing, and temperature of the freeze-drying process. Freeze-dried pumpkin obtained from nonpretreated pumpkin had the best sorption properties, whereas osmotic dehydration significantly decreased the water vapor adsorption ability of the investigated samples. Studies on the influence of different freezing methods on water vapor sorption showed that a combination method of freezing resulted in the best sorption properties. When the temperature of freeze drying was increased, the water vapor adsorption ability of the freeze-dried pumpkin also increased.

Keywords:

• Blanching
• Freeze drying
• Osmotic dehydration
• Pumpkin
• Sorption properties

Notes

^a Where A, B, C, D, F, G, H, k, and c are constants; a _w is water activity; and u is the water content (g H₂O/g dm).

^aWhere R ² is the correlation coefficient; RMS is the root mean square, and A. B. C. D. F. G. H. are constants.