The effect of phytosterols addition on the textural properties of extruded crisp bread

The aim of this work was to describe the texture of extruded bread produced with and without addition of phytosterols. The effect of a change in water activity on the mechanical and acoustic attributes of bread was also determined. The texture of extruded bread was analysed using acoustic and mechanical tests as well as a sensory panel. The acoustic signals generated during penetration were recorded using a microphone and an accelerometer. The rye extruded bread obtained with and without addition of phytosterols did not differ in terms of density, porosity or WAI. The higher values of a mechanical parameter (maximum force) and acoustic descriptors (acoustic energy, total number of acoustic events) indicated that bread produced with addition of phytosterols was harder and more crispy than rye bread, which was confirmed by sensory analysis. Water activity had a significant effect on the texture of extruded bread with phytosterols.