Glass Transition, Water Plasticization, and Lactose Crystallization in Skim Milk Powder

Survival of Salmonella enteric in skim milk powder with different water activity and water mobility

Recently, the safety of low water activity (aw) foods started to become a major concern. It has been observed that microorganisms may not grow in low-aw foods but can survive for rather long periods of time, representing significant risk. Most researchers have been concentrating on the role of water activity. However, little is known about the effect of water mobility on influencing the surviva...

Mutarotational Kinetics and Glass Transition of Lactose

Role of -Relaxation and Glass Transition in Understandings Stickiness of Milk Solids

Stickiness of powder particles is often responsible for their impaired flow characteristics. Stickiness resulted from glass transition showing a relationship with mechanical -relaxations, and stickiness occurred differently in dairy solids modified in their lactose and protein contents. Glass transition, -relaxation and stickiness properties of milk solids systems were related to their solids c...

Glass Transition, Crystallization of Glass-Forming Melts, and Entropy

A critical analysis of possible (including some newly proposed) definitions of the vitreous state and the glass transition is performed and an overview of kinetic criteria of vitrification is presented. On the basis of these results, recent controversial discussions on the possible values of the residual entropy of glasses are reviewed. Our conclusion is that the treatment of vitrification as a...

Glass transition and water effects on sucrose inversion by invertase in a lactose-sucrose system.

Enzymatic changes are often detrimental to quality of low-moisture foods. In the present study, effects of glass transition and water on sucrose inversion in a lactose-sucrose food model were investigated. Amorphous samples were produced by freeze-drying lactose-sucrose (2:1)-invertase (20 mg invertase/49.4 g of carbohydrate) dissolved in distilled water. Sorption isotherms were determined grav...