The strength characteristics of fine milk, agglomerated milk and potato starch were examined. Experiments were performed using the Jenike shear tester according to Euro- code 1 recommendations. The tester was 60 mm in diameter and the displacement velocity was 0.03 mm s�1. A reference normal stress ranging from 30 to 240 kPa was applied. Experiments revealed a significant effect caused by shear stress vibration re- sulting from dilatation and hardening of the material during the slow shearing phase of these tests. The frequency of these vibra- tions were found to decrease with an increase in normal stress. Two components of the total strength were suggested: the physical friction strength and the extra component of strength caused by dilatation.