HYDROTHERMAL TREATMENTS OF PEA STARCH AND FLOUR TO MODIFY STRUCTURE AND FUNCTIONALITY AND REDUCE STARCH DIGESTIBILITY
| dc.contributor.advisor | Ai, Yongfeng | |
| dc.contributor.advisor | Warkentin, Tom | |
| dc.contributor.committeeMember | Zhang, Haixia | |
| dc.contributor.committeeMember | Tanaka, Takuji | |
| dc.contributor.committeeMember | Zello, Gordon | |
| dc.contributor.committeeMember | Ghosh, Supratim | |
| dc.contributor.committeeMember | Zhu, Fan | |
| dc.creator | Cheng, Fan | |
| dc.date.accessioned | 2024-09-09T21:03:36Z | |
| dc.date.available | 2024-09-09T21:03:36Z | |
| dc.date.copyright | 2024 | |
| dc.date.created | 2024-08 | |
| dc.date.issued | 2024-09-09 | |
| dc.date.submitted | August 2024 | |
| dc.date.updated | 2024-09-09T21:03:36Z | |
| dc.description.abstract | This dissertation research aimed to use hydrothermal treatments to modify structure and functionalities and reduce starch digestibility of pea starch and flour. In the first study, heat-moisture treatment (HMT) was deployed to modify two wrinkled pea (74.2% and 76.5% amylose) and two round pea starches (35.9% and 34.8% amylose) at 35.0% moisture, 110°C or 130°C, and 6 h. After HMT, the modified pea starches exhibited greater gelatinization temperatures and lower gelatinization enthalpy changes (ΔH), lower pasting viscosities and gel hardness, and greater enzymatic resistance as compared to the native counterparts. The HMT-modified pea starches generated higher pasting viscosities and formed stronger gels when heated at 120°C in Rapid Visco Analyser (RVA), rather than 95°C, suggesting that the modified starches had stronger molecular entanglement than the native controls. The enhanced molecular entanglement also contributed to the reduced digestibility of HMT-modified starches after cooking in boiling water: After HMT, resistant starch (RS) contents of wrinkled and round pea starches increased from 18.2% – 21.4% to 22.7% – 29.9% and from 5.8% – 6.2% to 9.8% – 11.0%, respectively. This study demonstrated that the HMT-modified pea starches with diverse functional profiles and increased RS could be promising new ingredients for industrial applications. In the second study, extrusion combined with high-temperature drying (EHTD) treatment was developed as a novel hydrothermal approach to achieve comparable treatment effects as HMT for starch modification. For EHTD treatment, pea starch was firstly subjected to extrusion at a moisture level of 37.5% and a low-temperature profile (≤ 65°C), and then immediately dried at 130°C for 1 h. EHTD increased gelatinization temperatures, reduced ΔH, decreased the pasting viscosities and gel hardness, and enhanced the enzymatic resistance of pea starch. A glycemic response evaluation in 20 healthy human participants revealed that water-boiled EHTD-modified pea starch showed 22% reduction (p < 0.01) in plasma glucose incremental area under the curve (IAUC) in comparison with the native starch after consumption. Additionally, HMT-modified pea starch was prepared under the same conditions as those used in Study 1 for comparison. Overall, EHTD treatment exhibited similar treatment impacts on the structure, functional properties and digestibility of pea starch as compared to HMT. This research indicated that EHTD treatment could be used as a new, clean-label, and practical method for industrial starch modification to produce functional and low-glycemic ingredients. In the third study, EHTD treatment was employed to modify pea starch and dehulled pea flour using the same conditions as described in Study 2. EHTD altered the functionalities and digestibility of pea starch in similar patterns as those observed in the second study; in contrast, the treatment only marginally altered the properties of pea flour, which was attributable to protein and fiber interfering with starch molecular entanglement during modification. EHTD treatment slightly damaged starch and denatured protein in pea flour. Compared with native pea flour, the EHTD-modified flour showed marginally higher starch gelatinization temperatures, lower protein denaturation temperatures, lower total ΔH, and weaker gel hardness. After EHTD treatment, the RS content of cooked pea flour slightly increased from 0.2% to 1.2% (db). This study suggested that enhancing starch molecular entanglement was critical for EHTD treatment to alter functionalities and reduce starch digestibility of pea ingredients. The dissertation research provided information for the agri-food industry to produce pea ingredients with tailored functionality and nutritional value through clean-label modifications. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | https://hdl.handle.net/10388/15983 | |
| dc.language.iso | en | |
| dc.subject | Hydrothermal treatment | |
| dc.subject | pea starch and flour | |
| dc.subject | starch functionality | |
| dc.subject | starch digestibility | |
| dc.title | HYDROTHERMAL TREATMENTS OF PEA STARCH AND FLOUR TO MODIFY STRUCTURE AND FUNCTIONALITY AND REDUCE STARCH DIGESTIBILITY | |
| dc.type | Thesis | |
| dc.type.material | text | |
| thesis.degree.department | Food and Bioproduct Sciences | |
| thesis.degree.discipline | Food Science | |
| thesis.degree.grantor | University of Saskatchewan | |
| thesis.degree.level | Doctoral | |
| thesis.degree.name | Doctor of Philosophy (Ph.D.) |