Determination of the structural stability of a premix powder through the critical water activity

摘要: This paper analyses the structural stability of a premix powder that consists mixture whey protein isolate, soy sodium caseinate, carrot juice, and honey bee, which are mixed together by spray-drying. The is determined means its critical water activity (RHc) at 25 °C, three different procedures, namely, conventional graphical method, calculating inflection points in adsorption isotherms, digital image analysis on powders stored activities ( $$0.11\le a_{w}\le 0.53$$ ). These methodological approaches can predict value RHc reliably.