G N Subba Rao
Articles written in Proceedings – Section A
Volume 23 Issue 1 January 1946 pp 8-15
Casein has been spread from its aqueous solutions by different methods and it has been found that the modified band method is the most suitable for the study of protein films.
Effect of salts on the spreading of casein has been studied. The results obtained can be explained on the basis that two different factors, solubility and the electric charge of the protein molecule influence spreading.
Treatment of the protein with formaldehyde causes a decrease in spreading. Change in pH affects spreading of formolised casein to a smaller degree.
Sodium metaphosphate diminishes markedly the spreading of casein. Trichloracetic acid, however, has no effect.
Deaminisation of casein alters the spreading properties and gives unstable films on acidulated water. No films can be got on distilled water.
The spreading properties of an isodisperse fraction of casein have been studied. The limiting area of this fraction has been found to be of the same order as that of the original material.
Volume 24 Issue 3 September 1946 pp 277-286
Volume 25 Issue 3 March 1947 pp 221-228
A series of sorptions and desorptions of water vapour at 30° C., on gelatin, casein, egg albumin, denatured casein, denatured egg albumin have been conducted and in these systems either there is no hysteresis loop at all or the loop initially exhibited disappears on successive sorptions and desorptions.
These results indicate that the swelling of the adsorbent on imbibing the solvating liquid is responsible for the disappearance of the hysteresis effect.
Experiments on the sorption of ethyl alcohol at saturation pressure on the above proteins at 30°C. show that the nonsolvating liquid is either not adsorbed at all or taken up to a very small extent.
With casein and egg albumin, the sorptive capacities for water are lower in the denatured forms of the proteins. These results indicate a decrease in hydrophilic character of the proteins on denaturation.