Factors affecting the properties of rice flour: a review

Rice (Oryza sativa L.) is a global essential food. Rice flour production had a significant upsurge, leading to various development in rice-based food products. The properties of starch within rice flour are generally affected by different factors, resulting in rice flour with various physicochemical and functional properties. This article summarized the several factors that affect rice flour properties, including environmental conditions in terms of temperature extreme and soil conditions, milling methods, amylose and amylopectin composition, and endogenous protein and lipid. Overall, environmental conditions in extreme temperatures can influence the amylose content, altering the amylopectin chain length and functional and thermal properties, to be specific gelatinization temperature and pasting properties. As for soil conditions like water deficiency and salinity stress could affect the pasting properties, reduce amylose content, increase the swelling rate, and pasting properties due to the alteration of protein endosperm level in rice flour, respectively. Factors such as the milling method are capable of influencing the starch characteristics within rice flour, and wet-milled rice flour is more applicable in the development of gluten-free rice bread than dry-milled rice flour. Amylose and amylopectin composition were found to affect the texture of final products and the physicochemical properties of rice flour, such as swelling capacity, gelatinization temperature and pasting properties. Whereas endogenous protein and lipid can influence the swelling properties, water solubility index, gelatinization temperature and retrogradation rate by the formation of complexes with amylose, called amylose-protein and amylose-lipid. In general, different factors could lead to vast properties of rice flour that can affect its performance of flour.