In the case of 55.6% of fat participation, significant differences of a number of acoustic events were noticed between biscuits with 9.3% of inulin participation (C8) and the ones with 18.5% of inulin participation (C9). The highest number of acoustic events and the acoustic energy level were discovered (C8) (Table 3). Moreover, the biscuits C8 obtained high values of the other acoustic descriptors. The described changes indicate a significant effect of the addition of inulin at reduced fat content in the recipe on the acoustic properties of short-dough biscuits. The observed tendencies may be related with the biscuits structure and the content of fat. Most of dry crispy/crunchy food products have a porous structure consisting of beams and films of solid material surrounding air cells.