EFFECT OF ENZYMATIC HYDROLYSIS ON THE PHYSICOCHEMICAL, FUNCTIONAL, AND NUTRITIONAL PROPERTIES OF PEA AND FABA BEAN PROTEIN ISOLATES
| dc.contributor.advisor | Nickerson, Michael | |
| dc.contributor.advisor | Bhowmik, Pankaj | |
| dc.contributor.committeeMember | Tanaka, Takuji | |
| dc.contributor.committeeMember | Qiu, Xiao | |
| dc.contributor.committeeMember | Wu, Jianping | |
| dc.creator | Sareen, Joy | |
| dc.creator.orcid | 0000-0003-3391-1161 | |
| dc.date.accessioned | 2023-01-27T18:07:06Z | |
| dc.date.available | 2023-01-27T18:07:06Z | |
| dc.date.copyright | 2023 | |
| dc.date.created | 2023-01 | |
| dc.date.issued | 2023-01-27 | |
| dc.date.submitted | January 2023 | |
| dc.date.updated | 2023-01-27T18:07:07Z | |
| dc.description.abstract | This research focuses on examining the physicochemical, functional, and nutritional aspects of proteins in pea (PPI) and faba bean protein isolates (FBPI) after they were enzymatically hydrolysed using trypsin to varying levels of hydrolysis. The overall goal of the research was to enhance the aforementioned properties by hydrolysing the proteins to 5% to 20% degrees of hydrolysis (DH) and determining property changes, positive or negative, which occurred post–hydrolysis. Hydrolysis decreased protein content in both pulse protein isolates. Lipid content remained unaffected among faba bean samples, while it increased for pea hydrolysates (PPH). No significant changes were observed in the ash contents of the proteins for both pulses. All samples at pH 7.0 had a net negative surface charge (SC), while at pH 4.5, SC became more negative with hydrolysis for both protein hydrolysates. Surface hydrophobicity (SH), at pH 7.0, of untreated, and heat–treated FBPI were similar which was enhanced with hydrolysis. In the case of pea proteins, heating the isolate increased SH, while hydrolysis lowered SH as 5% and 10% DH samples exhibited lower SH than the heat–treated PPI. Surface tension (ST), in general, decreased upon hydrolysis. No substantial difference in interfacial tension (IT) was observed among untreated, heat–treated, and hydrolysed FBPI, while PPH showed less IT than the untreated, and heat–treated PPI. In terms of functional properties, solubility increased with DH for both pulse hydrolysates. Water holding capacity (WHC) of the untreated isolates for both pulses was the highest, followed by the heat–treated or hydrolysed isolates. Oil holding capacity (OHC) increased after hydrolysis for both pulse protein isolates. Foaming capacity (FC) of faba protein hydrolysates (FBPH) were significantly lower as compared to the untreated isolate at pH 4.5 and 7.0. In the case of pea, FC increased with hydrolysis at pH 4.5, while at pH 7.0, no significant change in FC was observed. Foaming stability (FS) increased in both pulse hydrolysates at pH 4.5. At pH 7.0, hydrolysis significantly lowered FS of both pulse proteins. At pH 4.5, hydrolysis enhanced emulsion activity index (EAI) of FBPI, while it decreased in case of PPI. At pH 7.0, EAI increased for both pulse samples, with an exception for heat–treated PPI which showed a massive decrease. At pH 4.5, hydrolysis decreased emulsion stability index (ESI) for FBPI while PPH had more ESI. At pH 7.0, no significant change in ESI was observed among faba bean samples while PPH showed a higher ESI than the untreated PPI. All samples were found limiting in tryptophan, except the untreated PPI which was limiting in the sulfur containing amino acids. In vitro protein digestibility (IVPD) suggested that protein digestibility decreased after hydrolysis for both pulses. In vitro protein digestibility corrected amino acid score (IVPDCAAS) suggested that protein digestibility increased after hydrolysis of FBPI, and was maximum at 10%DH, while it negatively affected PPI digestibility since even at 10% DH, digestibility was less than the untreated PPI. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | https://hdl.handle.net/10388/14451 | |
| dc.language.iso | en | |
| dc.subject | Enzyme hydrolysis | |
| dc.subject | plant protein | |
| dc.subject | faba bean | |
| dc.subject | pea | |
| dc.subject | isolate | |
| dc.subject | hydrolysate | |
| dc.subject | trypsin | |
| dc.subject | protein modification | |
| dc.subject | protein quality | |
| dc.title | EFFECT OF ENZYMATIC HYDROLYSIS ON THE PHYSICOCHEMICAL, FUNCTIONAL, AND NUTRITIONAL PROPERTIES OF PEA AND FABA BEAN PROTEIN ISOLATES | |
| 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 | Masters | |
| thesis.degree.name | Master of Science (M.Sc.) |