Sensory Perception of Rye Bran Particles of Varying Size and Concentration in a Viscous Phase

Sensory evaluation was performed to investigate how size and concentration of small rye bran particles in a continuous phase with varying viscosity influence the sensory perception of grittiness. The threshold for the sensation of grittiness of rye bran particles in a starch gel, evaluated by triangular sensory tests, was very low. The particles were discerned at a concentration of 0.1–0.3%, despite the fact that they were very small (20–180 μm). The sensory panel was able to detect the increase in particle concentration in a ranking test, but the ability to detect the increase in concentration was not influenced by particle size. The rheological properties of the medium did not influence the detection threshold. Practical Applications Due to health benefits, addition of dietary fiber in food products is popular. Rye bran is a by‐product, which is very high in dietary fiber, and for which new applications are requested. Rye bran consists mainly of insoluble dietary fiber and the rye bran particles are hard and irregular in shape. To understand the oral sensitivity of these kinds of particles is important to avoid the negative sensation of grittiness of dietary fiber fortified products. Since it was shown that even the size fraction of 20 μm was perceived as gritty at very low concentrations (0.2–0.3%), the milling technique is probably not the solution to reduce the grittiness. Preferably a way of making the particles softer, with less sharp edges should be sought, at least if the rye bran is going to be added to a smooth food matrix of a starch gel.