## 5 Pasting Properties of Pigmented Rice
### Dehulling, Parboiling, and Milling
These effects are attributed to the reduction in particle size and the corresponding increase in surface area [57]. [PERSON] et al. [55] reported that micronisation increased rice bran whiteness, solubility, and nutrient release, while it had no significant effect on oil binding or thermal index and lowered bulk density after extrusion stabilization. Micronisation also improved the release of phenolics, flavonoids, \(\gamma\)-oryzanol, and minerals, enhancing the functional and nutritional properties of rice bran, especially when combined with extrusion stabilization. Microfluidisation presents a promising approach for forming complexes between starches and fatty acids, which could possibly lead to the development of a novel resistant starch ingredient with enhanced viscosity and water-holding capacity. Additionally, [PERSON] et al. [58] reported that microfluidised cereal by-products contribute unique functional and nutritional benefits to bakery products. In this case, the microfluidisation resulted in more homogenous particle distribution with the formation of the finely separated fibrous structure with greater surface area, thus improving water holding and binding capacity. They stated that the increase in surface area of fibres allowed bran fibre to intertwine and form a strong fibrous matrix, providing higher yield stress and viscoelastic moduli values in batter samples. Fractionation, on the other hand, is a method used to produce valuable milling fractions of bran with distinct functional and technological characteristics. Dry fractionation is an eco-friendly and cost-effective method that involves the gradual grinding of whole cereal grains to reduce the particle size of the flour [59]. This process then separates fractions that are rich in peripheral tissues, which are abundant in dietary fibre and phenolic compounds. One physical fractionation is air classification, where two main fractions can be obtained: high protein fractions (coarse fraction) and high starch fractions (fine fraction) [60]. These fractions can be used accordingly to further enrich flour with specific components such as protein and starch. Additionally, this process can isolate specific compounds, such as phenolic compounds, which can be used to improve the nutritional and health benefits of food products. [PERSON] et al. [61] highlighted that fractionated bran (below 500 \(\upmu\)m) added to milled rice resulted in improved colour and nutritional benefits (total phenolic content >53% and antioxidant activity >60%). However, due to variations in components such as fat, ash, and damaged starch after the fractionations, rheological properties, and thereby end products, are affected. Air classification can be performed independently or in combination with the micronisation technique, further enhancing the physicochemical and nutritional properties of cereal grains. [PERSON] et al. [62] studied the effects of air classification, both with and without micronisation, on the lipid components of brown rice bran. Their findings revealed that total crude fat content was higher in the fine air-classified fractions, with polyunsaturated triacylglycerglycerols being the most abundant, while the concentration of monoacylglycerolglycerols increased in the fine fractions. Given the emulsifying properties of these compounds, this approach could be advantageous for the development of rice-based products. Combining micronisation with air classification has shown promising effects on wholegrain brown rice and could potentially be applied to pigmented rice. However, to date, no studies have specifically examined the use of micronisation, with or without air classification, to enhance the physicochemical and nutritional qualities of pigmented rice for product development, leaving this topic open for further investigation and discussion.