Influence of carbohydrate on the microparticulation process of whey proteins: structural modifications and indicators of the Maillard Reaction

With the growing demand for lactose-reduced foods, the development of versatile ingredients has gained prominence. This study evaluated the production of microparticulated whey proteins (MWP) with lactose (WL), glucose, and galactose (WGG) or without added carbohydrates (WOC), maintaining 6% protein. Structural modifications were analysed by particle size, sedimentation, chromatography, hydrophobicity, and sulfhydryl groups, in addition to the quantification of Maillard reaction markers. The samples presented similar size distribution and thermal denaturation, indicating a standardized process. The absence of carbohydrates preserved sulfhydryl groups, which may affect stability. Hydrophobicity correlated with changes in secondary structure. Among the Maillard markers, lysine, carboxymethylysine, and pyrraline remained stable; however, furosine and dicarbonyl compounds were higher in MWP-WGG due to the presence of glucose and galactose. Lactulose appeared only in products with lactose. The results indicate that the presence of carbohydrates, rather than their type, influences microparticulation, making MWP-WGG a promising ingredient for reduced-lactose products.