As will be observed, the effect of heat appears to be the same upon the
two typical gum arabics quoted above, an increase of temperature from
18° C. to 50° C. decreasing the viscosity by nearly one half in both
cases, and the same seems to be true of most gum arabics. Roughly also
the same holds good for Ghattis, as the following numbers show:
------------+-------------+------------|
Gum. | Z at 18° C. | Z at 50° C.|
------------+-------------+------------|
Gum arabic. | 1016 | 579 |
Gum arabic. | 428 | 228 |
Gum arabic. | 609 | 347 |
Gum arabic. | 581 | 258 |
Ghatti. | 572 | 306 |
Ghatti. | 782 | 418 |
---------------------------------------+
The following table shows the effect of heat upon the viscosity of a
typical Ghatti: