Dehydration by desorption and by spray drying of dairy proteins: influence of the mineral environment

• Published in: Drying technology Vol. 17; no. 7/8; pp. 1347 - 1357
• Main Authors: Schuck, P, Briard, V, Mejean, S, Piot, M, Famelart, M.H, Maubois, J.L
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01.01.1999; Taylor & Francis
• Subjects: dairy protein; dehydration; desorption; drying; Life Sciences; mineral environment; solubility; spray drying; spraying; water transfer
• ISSN: 0737-3937; 1532-2300
• DOI: 10.1080/07373939908917619

A drying method by desorption in a water activity meter was used to simulate the conditions of spray drying and to determine the water transfer inside dairy concentrates towards the surface and from the surface to the drying air. The concentrates were also spray dried and solubility index of powders were determined during reconstitution. Whey protein concentrates (WPC) and native phosphocaseinate suspensions (NPCS) were used to study the effect of NaCl (420 mM), CaCl 2 (222 raM), sodium phosphate (173 mM) and sodium citrate (238 mM) on the water transfers. The decrease in water transfer during drying was explained by the high hygroscopicity of added mineral salts to WPC. NaCl addition to NPCS decreased the water transfer during drying, but increased the solubility index. Citrate and phosphate addition to NPCS increased the water transfer during drying and reconstitution. CaCl 2 increased the water transfer during drying but the solubility index was always low. Results are discussed as a function of the aqueous environment, of the nature of mineral salts, of the structure of dairy proteins and of protein solvation.