In this study, four varieties of glutinous rice were screened out of 18 varieties as representative model inks. Gel prepared using variety WN9612 of high amylose content displayed high viscosity and large overall print deviation (OPD = 17.4 ± 0.4 %) due to difficulties in extrusion. Printed item by variety 19,415 of medium amylose content showed good printability (OPD = 4.4 ± 0.4 %) and highest hardness (197.5 ± 7.3 N). Similarly good printability was demonstrated by variety 19,416 (OPD = 4.1 ± 0.2 %) containing low amylose content but abundant protein and bound-water. Variety WN9446 lacking protein and moisture created item with fluid structure, lowest gel strength (738.5 ± 20.9 Pa) and standing ability. Therefore, low to medium amylose content rendered suitable viscosity, extrudability and printability of rice gel while non-starchy components predominated water mobility and texture of 3D printed items. This study for the first time establishes theoretical groundwork of selecting glutinous rice varieties with appropriate chemical composition as all-natural materials in 3D printing and food customization.
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