Status : Verified
| Personal Name | Bacas, Danielle Ann L. |
|---|---|
| Resource Title | Moisture adsorption isotherms of Pinilisa rice of different milling fractions and fragment sizes |
| Date Issued | 30 June 2017 |
| Abstract | Rice studies abound yet little is known about Pinilisa, an aromatic and pigmented traditional rice variety. The effects of milling fraction (MF) and kernel fragment size (FS) on the moisture adsorption properties of Pinilisa rice at 37oC were investigated. Paddy rice and three MF (husked, undermilled, and regular-milled) x three FS (whole, broken, and ground) combinations were desiccated until about 5% moisture content (d.b.) before hygroscopic equilibration by static gravimetric method at relative humidity (RH) values from 2 to 96% at 37oC. MF significantly affected hygroscopic equilibration time at 58% and 76% RH (p-value = 0.026 and 0.046, respectively) while FS, at 26% and 88% RH (p-value = 0.024 and 0.004, respectively). MF and FS interacted at 88% and 96% RH (p-value = 0.007 and 0.002, respectively). Equilibrium moisture content (EMC) increased with RH across MF and FS. ANOVA suggests that at 10% equilibrium RH (ERH), MF significantly affected EMC (p-value = 0.016), and at 2% and 10% ERH, FS significantly influenced EMC (p-value = 0.019 and 0.001, respectively). MF and FS interacted at 2%, 10%, and 96% ERH (p-value = 0.019, 0.001, and 0.019, respectively). EMC vs ERH plots indicated that most samples had type II isotherm. Moisture adsorption data at 37oC fitted the Guggenheim-Anderson-de Boer (GAB) and Modified Henderson (MHE) equations better than the other models tested based on goodness-of-fit criteria. The monolayer moisture content obtained using the Brunauer-Emmet Teller, GAB, and Modified GAB equations were 4.15-6.15% d.b, 6.21-14.66% d.b., and 4.85-33.62% d.b., respectively. The first inflection point ranged from 0.0919 to 0.1815 aw the second, from 0.8834 to 0.9223 aw at 3.93-6.64% and 11.82-12.05% MC d.b. To ensure shelf stability against moisture-related deterioration, Pinilisa rice samples must be stored under relative humidity conditions that correspond to their respective monolayer moisture contents. |
| Degree Course | Bachelor of Science in Food Technology |
| Language | English |
| Keyword | Rice--Effect of milling on |
| Material Type | Thesis/Dissertation |
Preliminary Pages
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Category : P - Author wishes to publish the work personally.
Access Permission : Limited Access