Instant Emulsions - Food Colloids: Self-Assembly and Material Science - page 420

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Figure 5 Change in viscosity in a Rapid Visco Analyser for 12.5 g oil, 11.25 g water and
different levels of xanthan/NaCl/lecithin: (a) E , 0.35:1.2:0.3; ' , 0.35:0:0.3;
m , 0.35:1.2:0; K , 0.35:0:0. (b) E , 1:1.2:0.3; ' , 1:0:0.3; m , 1:1.2:0; K , 1:0:0

are formed quickly, increasing the oil water interfacial area and easing the
passage of the polymer particles into the aqueous phase. The same final
viscosities are approached for equal polymer and salt contents, but the delay
in reaching these values is a function of the speed of hydration. What is also
notable is the effect that salt has at the different xanthan concentrations. At the
lower xanthan level the salt induces a sevenfold decrease in viscosity, whereas at
the higher level only a doubling of viscosity is seen. This can be explained in
terms of some earlier work in this area; 21 it is a consequence of the xanthan-
xanthan weak gel interactions, which are a function of both polymer and
electrolyte concentrations.