Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications
Thesis (MSc)--Stellenbosch University, 2026.
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | English |
| Published: |
Stellenbosch : Stellenbosch University
2026
|
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613886201462784 |
|---|---|
| access_status_str | Open Access |
| author | Du Toit, Tanja |
| author2 | Van der Merwe, Debora |
| author_browse | Du Toit, Tanja Van der Merwe, Debora |
| author_facet | Van der Merwe, Debora Du Toit, Tanja |
| author_sort | Du Toit, Tanja |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MSc)--Stellenbosch University, 2026. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/135779 |
| institution | Stellenbosch University (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:43:15.981Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2026 |
| publishDateRange | 2026 |
| publishDateSort | 2026 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/135779 Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications Du Toit, Tanja Van der Merwe, Debora Sigge, Gunnar Hayward, Stefan Stellenbosch University. Faculty of AgriSciences. Dept. of Food Science. Thesis (MSc)--Stellenbosch University, 2026. Du Toit, T. 2026. Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications. Unpublished masters thesis. Stellenbosch: Stellenbosch University [online]. Available: https://scholar.sun.ac.za/items/563c829d-ea40-4429-a05d-62ea2c6af8b0 In South Africa, low-grade potatoes contribute significantly to food waste and economic losses, underlining the need for value-added uses within the food industry. The aim of this study was to develop a functional potato flour from low-grade potatoes and explore its potential for novel applications, while also evaluating key aspects of its commercial viability. Potato flour is commonly used as a thickening agent due to its high starch content, but its utilisation in other functional roles is still underdeveloped. Enzymatic hydrolysis, combined with either oven-drying or freeze-drying, was applied as the processing treatments to modify the functional properties of potato flour. The aim was to determine which treatment produced potato flour with the most versatile physicochemical and functional properties for novel food applications. Low-grade potatoes were processed into four flour treatments: untreated oven-dried (Un_OD), untreated freeze-dried (Un_FD), enzymatically hydrolysed oven-dried (EnzH_OD), and enzymatically hydrolysed freeze-dried (EnzH_FD). Before flour production, enzymatic hydrolysis was optimised using α-amylase (9.6 U/g) and glucoamylase (5 U/g), resulting in the highest glucose release of 5.61 mM. The functional properties of potato flour were significantly (p < 0.05) influenced by processing treatments. EnzH_OD flour had the highest a* (red) and b* (yellow) values due to Maillard browning, whereas freeze-dried flours retained higher L* (white) values associated with greater consumer acceptance. The EnzH_OD flour had a high bulk density, rendering it suitable for thickening functions, while the freeze-dried flours (Un_FD and EnzH_FD) had lower bulk densities with increased suitability for infant foods and baking. The Un_FD flour demonstrated extremely poor flowability associated with clumping and processing issues. The EnzH_OD potato flour had the lowest water holding capacity (160.8%) and oil-holding capacity (77.7%), indicating reduced functional performance, flavour retention and mouthfeel for bakery products. Water solubility was highest in the EnzH_OD (66.5%) and EnzH_FD (65.9%) due to enzymatic hydrolysis, increasing its potential for beverage applications. Overall, the EnzH_FD potato flour demonstrated the greatest application potential, supported by its enhanced functional properties and lightest colour. Nutritional analysis of the EnzH_FD potato flour revealed a protein content (10.7 g/100g) comparable to wheat flour and higher than most alternative flours, as well as fibre content (8.0 g/100g) exceeding wheat, rice, oat and maize flours. Mineral analysis showed higher total mineral content than wheat and commonly used gluten-free flours, with a notably high potassium content (1 731 mg/100g). Microbiological analyses of the potato flour, including Total Plate Count, Enterobacteriaceae, yeast and mould, Salmonella spp. and Bacillus cereus, were all below recommended limits, confirming safety for consumption over the 2.5 month testing period. Accelerated shelf-life testing (ASLT) at 25, 35 and 45°C over 42 days, based on total colour difference (ΔE), predicted a shelf-life of 2.2 months, after which browning would become visually noticeable. The results of this study indicate that the EnzH_FD potato flour is functionally enhanced, nutritionally valuable and microbiologically stable, supporting its commercial viability as a potential novel food product or application. These findings contribute to scientific knowledge on starch modification, product development within the gluten-free market and the sustainable management of low-grade potatoes. Masters 2026-04-10T08:09:26Z 2026-04-10T08:09:26Z 2026-03 Thesis https://scholar.sun.ac.za/handle/10019.1/135779 en Stellenbosch University 128 pages : ill. application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Du Toit, Tanja Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications |
| title | Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications |
| title_full | Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications |
| title_fullStr | Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications |
| title_full_unstemmed | Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications |
| title_short | Development of a Functional Potato Flour: From Low-Grade Potatoes to Potential Novel Food Applications |
| title_sort | development of a functional potato flour from low grade potatoes to potential novel food applications |
| url | https://scholar.sun.ac.za/handle/10019.1/135779 |
| work_keys_str_mv | AT dutoittanja developmentofafunctionalpotatoflourfromlowgradepotatoestopotentialnovelfoodapplications |