Multifractal breakage patterns of thick maltodextrin agglomerates

Abstract

Breakage of food materials affects operations in industry such as storage, transport and quality control, and has an influence on sensorial attributes. However, the geometry of the breakage pattern is a complex and rarely studied subject. Maltodextrin has been used as an ingredient in food related systems. The aim of this work is to characterise the geometry of the breakage patterns in thick maltodextrin agglomerates (MDAs), by digital image analysis (DIA) and multifractal spectra. Results showed that morphology of the breakage pattern was independent of the powder particle size, agglomerate thickness and compaction force. On the other hand, significant differences in pattern's lacunarity were found between the different loads applied whereas different distributions of the irregularity of the breaking pattern measured from the centre to the border of the MDA were obtained. Multifractal spectra reported different generalised fractal dimensions and shapes. Therefore, the breakage profile has a heterogeneous shape with microstructural differences along the breakage line. To the best of our knowledge, this is the first time that multifractal analysis has been used to characterise the breakage pattern geometry in thick MDAs. Size distributions of residual particles (RP) generated during the fracturing process were correlated with the breakage pattern of the material. This study contributes to the quantitative analysis and understanding of the complex structure of the breakage pattern and provides valuable information for further research on brittle food products.