Drying of Foamed Biological Materials: Opportunities and Challenges

Abstract

An overview is provided on hot air drying of foamed materials in a thin layer (foam-mat drying), foam-spray drying, microwave-assisted drying of liquid foams, as well as microwave drying of frozen foams with and without dielectric solid inserts, used as complementary heat sources. In particular, the mechanisms of heat and moisture transport during the drying of foams are identified. The effects of foam characteristics (e.g., foam density and stability) and drying conditions (temperature, air velocity) on drying kinetics and product quality are examined, and the differences between the drying of non-foamed and foamed materials are discussed.

Keywords:

• Dielectric material
• Drying kinetics
• Foam-mat drying
• Freeze drying
• Microwave drying
• Spray drying

Acknowledgments

This study was supported by Fonds Québecois de Recherche en Sciences de la Nature et les Technologies (Québec, Canada) through the grant “Action Concertée sur les Nutraceutiques et les Aliments Fonctionnels.”

Notes

© Her Majesty the Queen in Right of Canada, as represented by the Minister of Natural Resources, 2006.