The Global Leader In Viscosity For Over 75 Years


Brookfield AMETEK

Pet Treats

Test Principle

Evaluation of the bite feel of pet treats.


Veterinary medicine is continually improving drug delivery systems to make it easier and more convenient for pet owners to administer medicine to their pets. Disguising a pill in a ball of hamburger does not usually prove very effective. We most often find the pill on the floor and the hamburger eaten. Pets can be quite efficient at sorting the medicine from the meat.

Bite sized pet treats on the other hand are almost always eagerly accepted by our pets, so veterinary companies are now finding ways to integrate medicine into what looks and tastes like a bite-sized pet treat. It’s not a matter simply of molding a pill into the center of the snack. The active ingredient is mixed into the slurry before the snack is molded.

An acceptable bite feel is one very important physical property of these “treats”. To measure this property, a shear compression test using a texture analyzer is a very efficient tool to maintain good quality control of bite feel.



CT3 with 50kg load cell
Velodkevitch bite jaw (TA-VBJ)
Fixture Base Table (TA-BT-KIT)
Sample Carrier


Test Type: ompression
Pre-Test Speed: 0.5 mm/s
Test Speed: 2 mm/s
Post-Test Speed: 1 mm/s
Distance: 6 mm
Trigger Force: 0.49 N

Results & Discussion

Graph 1 shows results for the one inch square chews.

Figure 1

Graph 2 shows the same test results for the smaller one half inch square chews. The similar curves on the same material of different sizes demonstrates that the test accurately measures similar physical properties, even on samples of different sizes.

Figure 2

Graph 3 shows two tests of one inch square chews made of a less cohesive material.

Figure 3

The samples crumbled early in the penetration. This can be seen on the graph as a rapid loss of load force soon after the hardness peak. The effect is seen quite noticeably in the Hardness Work Done test statistic and clearly demonstrates the ability of this test to discriminate physical property differences. Because it is a single compression test, it is all about initial bite feel. It says nothing about chewiness.