High shear mixer granulation using food grade binders with different thickening power

- High shear granulation was successfully performed using alternative thickening agents.
- It was possible to predict granule size through experimental design techniques.
- Agents with high thickening power reduced water required for granulating up to 25%.

Mixer agglomeration, in particular high shear wet granulation, is a unit operation typically used in the pharmaceutical industry to improve the flowability, the compressibility, the dosing accuracy during tableting or the content uniformity of a blend. Thanks to its advantages (production of spherical and dense granules, reduction of production time), this technique can be potentially successful also in the food industry as for example in the production of dietary supplements. In this work four thickening agents (povidone, maltodextrin, k-carrageenan and xanthan gum) have been tested to study their effects on the granule growth behavior and on some technologically relevant granule properties (size, shape, strength and flowability). Experiments highlighted the full feasibility of the process and the possibility of using these agents to get products with satisfactory technological properties. The dependence of product properties on the formulation variables (water and binder amount) has been analyzed according to a multivariate approach and a robust predictive tool for the granule size has been developed. Furthermore it was observed that a reduced amount of binding liquid (water) can be used in the presence of strongly thickening binders with a reduction up to 25%. This would decrease drying time and energy requirement and be beneficial especially in the food and food supply industry where products have generally lower added value than in the pharmaceutical one and reducing production costs is critical.