Physical Chemistry of Foods

by

x¼

d

6

1

j

1

jmax



ð 9 :1bÞ

wherejmaxequals, for instance, 0.7. Results for both equations are in Figure

9.6, and it is seen that the dependence on jis considerable and that

especially at lowjthe difference between the two is considerable.

Pore Size. If aggregated particles make up a continuous phase, and

the voids are filled with a continuous fluid phase, an important characteristic

is the (average) pore size, i.e., the width of the channels between particles.

This applies to powders and to particle gels. The pore size greatly affects

FIGURE9.6 Average distancexbetween spheres of diameterdas a function of
volume fractionj, according to Eqs. (9.1a) and (9.1b).