Micronization of Whole Grain Flours: Innovative Approaches for Improving Functional Characteristics and Product Performance

Abstract

Rising consumer demand for nutrient-dense cereal products has renewed interest in whole-grain ingredients, yet the coarse texture and altered functional behavior of whole-grain flours limit their application in many foods. Micronization, the controlled reduction of particle size by mechanical or thermal–mechanical approaches (e.g., ball, jet, roller, cryogenic, ultrafine, and IR-based methods), can modify flour microstructure and molecular organization. This review investigates recent studies on micronization of whole-grain flours, comparing techniques and summarizing their effects on structural, physicochemical, techno-functional, thermal, and rheological properties, and final product quality. It also evaluates benefits and trade-offs (e.g., improved digestibility and bioactive release vs. excessive starch damage and energy costs), and highlights analytical methods and application-specific optimization strategies. Micronization is a promising, sustainable route to reconcile whole-grain nutrition with consumer-acceptable functionality: appropriately reduced particle size enhances hydration, pasting behavior, bioactive release, and dough handling, improving texture and shelf life in many applications. However, over-micronization can increase damaged starch, weaken starch–protein networks, and impair product quality, so process parameters must be tailored to grain type and intended use. Future work should prioritize scale-up, combined modification strategies (e.g., enzymatic or hydrothermal pairing), and targeted studies of digestibility and glycemic response to fully realize micronization's potential.