Optimizing processing sequences in combined techniques for rice starch modification: A mini review of current understanding

Rice starch modification has gained significant attention due to its widespread applications in food industries. Despite its advantages including hypoallergenic properties, fine particle size, neutral taste, and bright white color, native rice starch faces critical limitations such as poor water solubility, high sensitivity to shear forces, and inability to withstand high temperatures. While diverse single modification methods have been developed, they often face challenges including high energy costs, time-consuming processes, and limited modification effects, particularly due to rice starch's inherently stable A-type crystalline structure. This review systematically examines how strategically combining multiple processing techniques can overcome these limitations through synergistic effects. The paper analyzes the rationale, optimal processing sequences, and applications of combined food processing techniques for various rice-based products and materials. Chemical modifications and mechanical-assisted treatments (pulsed electric field, ultrasound) typically serve as effective pretreatments, with citric acid showing the highest effectiveness among acid modifications. PEF pretreatment is specifically combined with enzymatic hydrolysis to overcome inefficiencies in modifying high-amylose rice, while ultrasound treatment creates porous structures and is preferentially applied to brown rice to improve sensory attributes and reduce cooking time. Traditional thermal treatments (annealing, heat-moisture, dry heat) and innovative methods (microwave, infrared radiation) demonstrate varying effectiveness based on rice amylose content, with greater success in modifying low-amylose varieties. Notably, infrared radiation shows high potential for modifying pigmented rice while preserving bioactive compounds. Novel approaches including 3D printing and high-pressure homogenization are also explored. Cold plasma treatment emerges as particularly promising for industrial-scale, eco-friendly starch modification. The review addresses key implementation challenges, particularly raw material variability and processing parameter optimization, proposing data-driven solutions for standardizing production processes.