Texture change method

The interpretation of TG observations frequently requires support from complementary measurements. Important methods to confirm the identities of rate processes investigated by TG often usefully include enthalpy measurements (DSC and DTA), evolved gas analysis (EGA), structure determinations (x-ray diffraction), microscopy (textural changes of solids), etc. In particular, within the pharmaceutical arena, there is often a tendency to assume that mass losses are exclusively due to water it is recommended that such an assumption should be made with care. 

The chemical modification of alumina both by alkali and acid leads to the textural as well as surface chemistry changes on the surface of alumina. The total Lewis acidity and Bronsted acidity and basicity are altered to the desired levels. The textural changes like surface area and pore size distribution can be deduced from the adsorption and desorption of N2 at 77K on the four alumina samples. The surface area calculated by BET method for the four adsorbents is given in Table 3. 

The a- method was used to study the textural changes of the adsorbents by using the adsoption of N2 data at 77K. The basic principle of the a-method is to compare the nitrogen... 

Because overblanching may result in undesirable changes in color, flavor, taste, and texture and the loss of nutritive value, it is as important to avoid overblanching as underblanching. The availability of a method for the detection of overblanching is indicated, but so far as the writer is aware, none exists at the present time. In view of the fact that complete peroxidase inactivation is not required for quality protection, a measurement of residual peroxidase activity might provide the basis for such a test. 

Pulsed electric field is another alternative to conventional methods of extraction. PEF enhances mass transfer rates using an external electrical field, which results in an electric potential across the membranes of matrix cells that minimizes thermal degradation and changes textural properties. PEF has been considered as a nonthermal pretreatment stage used to increase the extraction efficiency, increasing also permeability throughout the cell membranes. 

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