Structural characteristics and functional properties of fiber-rich by-products of white cabbage modified by high-energy wet media milling

Abstract

The recovery of residues and by-products of the food industry plays an important role in terms of sustainable management. For this reason, the aim of this study was to analyse the effect of wet milling parameters on dietary fiber concentrates of white cabbage by products or, more precisely, the stalks of cabbage. The input of hydraulic shear-energy during wet milling process leads to a partial modification of the structure of fiber components to obtain compounds with high water- and oil-binding properties. Furthermore, the wet milling parameters affect the functional properties of the fiber concentrates. A mathematical model was developed which relates the functional properties to the parameters of the colloid mill such as slurry concentration, milling time, agitation speed and particle size distribution. A slurry of the grounded material is forced into the milling gap. Grinding is autogenous as a result of collisions between rotating particles. All of the material in the process stream is being grounded finer than the gap setting and grinding can be optimized by adjusting mill operating parameters. The identification of the relations between milling parameters and functional properties is necessary in order to comprehend the processing characteristics of the material in the context of fiber enriched food products manufacturing.