Particle Size Analysis by wet Laser Diffraction for anhydrous food suspensions: Application to sunflower tahini

Abstract

Particle size is a critical quality parameter of food suspensions, influencing their rheological behaviour, overall stability as well as sensory perception. Sunflower paste was considered an example for a complex food matrix, based on its heterogeneous chemical composition, thus being a representative food model for the oilseed-based products. The aim of this paper was to develop a new method to characterize anhydrous food suspensions particle size distribution (PSD), by using a representative sunflower tahini sample characterized by a broad particle size distribution and coarse appearance. Hexane was selected as bring the appropriate dispersant to measure PSD of sunflower kernel paste. After performing a stirrer rate titration, the stirrer speed of 2400 rpm was proposed. Measurements stability was assessed, overall trimodal PSD curves were overlapping when performing 15 consequently determinations during 30 minutes. The newly developed method is consistent, being confirmed by analysing different fractions obtained by sieving.