Impact of Short-Time Micronization on Structural and Thermal Properties of Sugar Beet Fibre and Inulin

RESEARCH BACKGROUND: By tailoring dietary fibre’s structural and physicochemical properties, their functionality and applicability can be remarkably increased. One of the approaches used in this respect is fibre particle size reduction. Accordingly, the present study explores the impact of short-time micronization in a planetary ball mill on structural and thermal changes of modified and commercial sugar beet fibre, inulin and sucrose for their potential application as food excipients. EXPERIMENTAL APPROACH: Short-time micronization in a planetary ball mill (30 and 60 min) was applied for particle size reduction of modified and commercial sugar beet fibre, inulin and sucrose as less energy-consumptive and less destructive approach than long-time micronization. Dietary fibre and sucrose samples were characterised in terms of particle size, morphology, intermolecular bonds and presence of functional groups, crystallinity and thermal properties, before and after the short-time micronization. RESULTS AND CONCLUSIONS: Particle size was successfully reduced to micron-scale already after 30 min of micronization in most of the samples without significant changes in thermal properties and crystallinity or present functional groups. An enhanced particle size decrease with prolonged micronization time (60 min) was noticed in modified sugar beet fibre with slightly wider particle size distribution than in other examined samples. Furthermore, morphology and exposure of the present functional groups in samples were altered by the micronization, which is favourable for their further application as excipients in the food matrix. NOVELTY AND SCIENTIFIC CONTRIBUTION: The corresponding research reports the short-time micronization impact on sugar beet fibre and modified sugar beet fibre, inulin and sucrose for the first time, hence contributing to the widening of their application as excipients in diverse products.