Development and evaluation of low glycemic nutritionally and functionally enhanced gluten-free pasta from Khai Mod Rin rice resistant starch modified via green processing | |
| Author | Sirisopa Junden |
| Call Number | AIT Diss. no.FINH-26-01 |
| Subject(s) | Gluten-free foods Rice--Nutrition Starch Glycemic index |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of doctor of Philosophy in Food Innovation, Nutrition and Health |
| Publisher | Asian Institute of Technology |
| Abstract | The study aimed to improve the digestibility and physicochemical properties of Khai Mod Rin rice (Oryza sativa L.), a non-glutinous and underutilized Thai variety, through green starch modification technologies. The first objective was to enhance resistant starch type III (RS3) formation in Khai Mod Rin rice starch using autoclaving–chilling (A/C) cycles. Starch samples were autoclaved at 135 °C for 30 min, followed by cooling at 24 °C for 2 h. This treatment resulted in a substantial increase in RS3 content (3.69% to 49.71%) with a reduction in glycemic index (73.93 to 59.31). Swelling power and solubility decreased, whereas water- and oil-holding capacities and bile acid binding capacity increased, indicating improved functionality. Crystallinity shifted from A- and V-type to predominantly V-type, consistent with RS3 formation. A rise in Tc and enthalpy reflected stronger and more thermally stable starch structures, and changes in pasting properties indicated modified gelatinization behavior. The second objective was to produce resistant starch (RS) using two approaches: (i) mixing starch with distilled water followed by microwave–ultrasound treatment (MU; control) and (ii) treating plasma-activated water for 2.5–10 min before starch addition and subsequently subjecting it to microwave–ultrasound modification (PAW2.5–PAW10MU). PAW2.5– PAW7.5MU significantly increased RS, amylose contents, water-holding capacity, and bile acid binding capacity, while reducing glycemic index (GI), solubility, and swelling power. PAW7.5MU exhibited the highest RS content (50.32%) and lowest glycemic index (GI) (59.13), whereas PAW10MU caused structural over-disruption. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) indicated no new functional groups and mixed B- and V-type crystallinity. The PAW7.5MU treatment showed the highest relative crystallinity (23.49%) and molecular order. The final objective was to apply PAW7.5MU as an ingredient for gluten-free pasta (GFP) development due to its lowest glycemic index (GI) and shortest processing time. GFP was formulated by replacing native Khai Mod Rin rice flour with PAW7.5MU RS at levels of 0–45% (w/w). All formulations contained 13.96–16.04% protein (excellent source of protein) and 6.38–8.52% dietary fiber (high-fiber foods). RS content increased from 1.54% to 34.74%, while glycemic index (GI) decreased from 58.56 to 53.55, with 30–45% RS pasta classified as low glycemic index (GI) (<55). Cooking properties changed minimally, with water absorption of 44.74–50.14%, low cooking loss (0.80–2.08%), and slightly higher breakage (0–8.33%). Textural parameters showed moderate hardness (43.84–39.13 N), springiness (88–82%), cohesiveness (0.37–0.35), and adhesiveness (1.28–2.19 N·s). Fourier transform infrared spectroscopy (FTIR) confirmed increased molecular order (1045/1015 cm⁻¹), while differential scanning calorimetry (DSC) showed higher Tp (84.79–87.59 ℃) and reduced ΔH, indicating starch rearrangement. SEM revealed denser, more compact structures at higher RS levels, and X-ray diffraction (XRD) showed a shift from A- and V-type crystallinity in the control and RS15% to dominant B- and V-type in RS30% and RS45%. Overall, the A/C and PAW–MU processes each improved the functional, structural, and nutritional properties of Khai Mod Rin rice starch. Together, these results demonstrate green and sustainable strategies for generating RS-rich, low-glycemic ingredients for functional and gluten-free foods. |
| Year | 2026 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Innovation, Nutrition and Health (FINH)/Former code name = FI |
| Chairperson(s) | Anal, Anil Kumar;Atikorn Panya (Co-chairperson) |
| Examination Committee(s) | Darniadi, Sandi;Tsusaka, Takuji W.;Sujitta Raungrusmee |
| Scholarship Donor(s) | Royal Thai Government;AIT Fellowship |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2026 |
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