Introduction
Rotational rheometers are not limited to studying the flow properties and viscoelastic behavior of materials. Devices with high normal force capabilities can also measure snap ability – a characteristic describing how food is perceived during the first bite. These measurements are conducted using a texture analysis accessory, as shown in figure 1.
Experimental
In this process, the solid food sample, such as a biscuit or cookie, is placed on the lower fixture of the texture analysis setup (figure 1). The upper fixture moves downward at a constant speed until it reaches a gap of 0 mm, while the normal force is continuously recorded.
To illustrate this, a test was conducted comparing the snap-ability of a milk chocolate-coated biscuit stored at room temperature with one stored in the refrigerator. The upper fixture was programmed to descend at a speed of 50 mm/s.
Measurement Results
The results, shown in figure 2, reveal that the force required to snap the refrigerated biscuit is nearly double that of the biscuit stored at room temperature.
