State diagram, freeze-drying

State Diagram for Freeze-Dried Plum and Glass Transitions of Plum Skin and Pulp... 

The objective of this work was to study the state transitions of freeze-dried plum and to draw the corresponding state diagram for this material. Class transitions of separated plum skin and pulp were also investigated, aiming to clarify the effect of each of these fractions on the behavior of the whole fruit. 

State diagram of freeze-dried plum (skin/pulp at the natural proportion) ( , First T A, T X, I m +, Second Tg). 

A state diagram for freeze-dried plum was obtained and the Gordon-Taylor model could adequately represent the sugar matrix glass-transition curve. 

Telis, V.R.N. and Sobral, P.J.A. Glass transitions and state diagram for freeze-dried pineapple, Lebensm.-Wiss. Technol., 34, 199, 2001. 

Figure 11.5 State diagram for an aqueous sugar solution and typical freeze-drying curve...

Fig. 3.3 Typical state diagram of a standard formulation used for freeze-drying of pharmaceutical proteins.

Fig. 1 Different routes for gel drying illustrated in the phase diagram. In freeze drying the hquid solvent is replaced by gas via freezing and subsequent sublimation. In convective drying the replacement occurs via direct evaporation, whereas in supercritical drying the hquid solvent is first brought to the supercritical state by heating under pressure and then to the gas state (taken from [23])...

The RMS-800 mechanical pressure spectrometer (Rheometrics, Piscataway, N.J.) was used to determine dynamic properties. Freeze-dried samples were brought to the appropriate moisture content with distilled water, equilibrated to different relative humidities and then tested. Frequency and temperature sweeps provide infonnation about the stmcture of the biopolymer and supply parameters to define the state diagram. 

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