Abstract:
Broken rice noodles from noodle factory were milled into flour (BRNF) and combined with rice flour (RF), tapioca starch (TS) and its derivatives (heat-moisture treated tapioca starch, HMT-TS, and cross-linked tapioca starch, CTS) to make composite rice noodles. Heat-moisture treatment (HMT) was applied to TS having various moisture contents (17, 20 and 23%, wb) at different temperature levels (95, 110 and 125 °C) for 16 h. HMT displayed influence on the apparent amylose contents, resistant starch levels, X-ray diffraction characteristics, thermal behaviors, swelling power and solubility, pasting characteristics and gel textures of TS. BRNF displayed some distinct physicochemical properties from RF such as higher resistant starch level, unique X-ray diffraction characteristics, retrogradation behavior, suppressed swelling and pasting, and weaker gel texture. Although the partial substitution of BRNF for RF did not change the composition-property relationships of RF-starch blends, decrease in swelling, pasting and gelling of RF combinations were observed. Among RF combinations, those that contained HMT-TS (20-125) failed to be used for noodle making, which was due to the inferior pasting properties of HMT-TS (20-125) to those of TS and CTS. Composite rice noodles prepared from flour combinations containing BRNF showed cooking and textual qualities close to those of commercial one. And flour blend of RF/BRNF/TS was considered preferable to reusing broken rice noodles.
