The viscosity of heat treated creams increased with time (t). The rate (k) was dependent on homogenization pressure, fat content and heat treatment temperatures. Viscosity and its rate of increase could be related by the expressions:
log η = log η0 + kt
(where η0 is the viscosity at t = 0),
log η0 = a1 + b1φ/d
(where φ is the fat volume fraction, d is the globule diameter) and
k = a2 + b2φ/d.
Different values of a1b1a2 and b2 were found for homogenized and unhomogenized creams.