The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake
Rapeseed is the second most cultivated oilseed after soybean and is mainly used to produce vegetable oil. The by-product rapeseed press cake is rich in high-quality proteins, thus having the possibility of becoming a new plant protein food source. This study aimed to investigate how the precipitatio...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-05-01
|
| Series: | Molecules |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1420-3049/27/9/2957 |
| _version_ | 1797503650633875456 |
|---|---|
| author | Cecilia Ahlström Johan Thuvander Marilyn Rayner María Matos Gemma Gutiérrez Karolina Östbring |
| author_facet | Cecilia Ahlström Johan Thuvander Marilyn Rayner María Matos Gemma Gutiérrez Karolina Östbring |
| author_sort | Cecilia Ahlström |
| collection | DOAJ |
| description | Rapeseed is the second most cultivated oilseed after soybean and is mainly used to produce vegetable oil. The by-product rapeseed press cake is rich in high-quality proteins, thus having the possibility of becoming a new plant protein food source. This study aimed to investigate how the precipitation pH affects the protein yield, protein content, and emulsifying properties when industrially cold-pressed rapeseed press cake is used as the starting material. Proteins were extracted under alkaline conditions (pH 10.5) with an extraction coefficient of 52 ± 2% followed by precipitation at various pH (3.0–6.5). The most preferred condition in terms of process efficiency was pH 4.0, which is reflected in the zeta potential results, where the proteins’ net charge was 0 at pH 4.2. pH 4.0 also exhibited the highest protein recovery yield (33 ± 0%) and the highest protein concentration (64 ± 1%, dry basis). Proteins precipitated at pH 6.0–6.5 stabilized emulsions with the smallest initial droplet size, although emulsions stabilized by rapeseed protein precipitated at pH 5.0–6.0 showed the highest emulsion stability at 37 °C for 21 days, with a limited layer of free oil. Overall, emulsion stabilized by protein precipitated at pH 5.0 was the most stable formulation, with no layer of free oil after 21 days of incubation. |
| first_indexed | 2024-03-10T03:53:44Z |
| format | Article |
| id | doaj.art-81687f287de849638e171e8647956528 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T03:53:44Z |
| publishDate | 2022-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-81687f287de849638e171e86479565282023-11-23T08:52:10ZengMDPI AGMolecules1420-30492022-05-01279295710.3390/molecules27092957The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press CakeCecilia Ahlström0Johan Thuvander1Marilyn Rayner2María Matos3Gemma Gutiérrez4Karolina Östbring5Department of Food Technology Engineering and Nutrition, Lund University, Naturvetarvägen 12, 223 62 Lund, SwedenDepartment of Food Technology Engineering and Nutrition, Lund University, Naturvetarvägen 12, 223 62 Lund, SwedenDepartment of Food Technology Engineering and Nutrition, Lund University, Naturvetarvägen 12, 223 62 Lund, SwedenDepartment of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, SpainDepartment of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, SpainDepartment of Food Technology Engineering and Nutrition, Lund University, Naturvetarvägen 12, 223 62 Lund, SwedenRapeseed is the second most cultivated oilseed after soybean and is mainly used to produce vegetable oil. The by-product rapeseed press cake is rich in high-quality proteins, thus having the possibility of becoming a new plant protein food source. This study aimed to investigate how the precipitation pH affects the protein yield, protein content, and emulsifying properties when industrially cold-pressed rapeseed press cake is used as the starting material. Proteins were extracted under alkaline conditions (pH 10.5) with an extraction coefficient of 52 ± 2% followed by precipitation at various pH (3.0–6.5). The most preferred condition in terms of process efficiency was pH 4.0, which is reflected in the zeta potential results, where the proteins’ net charge was 0 at pH 4.2. pH 4.0 also exhibited the highest protein recovery yield (33 ± 0%) and the highest protein concentration (64 ± 1%, dry basis). Proteins precipitated at pH 6.0–6.5 stabilized emulsions with the smallest initial droplet size, although emulsions stabilized by rapeseed protein precipitated at pH 5.0–6.0 showed the highest emulsion stability at 37 °C for 21 days, with a limited layer of free oil. Overall, emulsion stabilized by protein precipitated at pH 5.0 was the most stable formulation, with no layer of free oil after 21 days of incubation.https://www.mdpi.com/1420-3049/27/9/2957rapeseed press cakeprotein extractionprotein recoveryplant proteinsemulsion stability |
| spellingShingle | Cecilia Ahlström Johan Thuvander Marilyn Rayner María Matos Gemma Gutiérrez Karolina Östbring The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake Molecules rapeseed press cake protein extraction protein recovery plant proteins emulsion stability |
| title | The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake |
| title_full | The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake |
| title_fullStr | The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake |
| title_full_unstemmed | The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake |
| title_short | The Effect of Precipitation pH on Protein Recovery Yield and Emulsifying Properties in the Extraction of Protein from Cold-Pressed Rapeseed Press Cake |
| title_sort | effect of precipitation ph on protein recovery yield and emulsifying properties in the extraction of protein from cold pressed rapeseed press cake |
| topic | rapeseed press cake protein extraction protein recovery plant proteins emulsion stability |
| url | https://www.mdpi.com/1420-3049/27/9/2957 |
| work_keys_str_mv | AT ceciliaahlstrom theeffectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT johanthuvander theeffectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT marilynrayner theeffectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT mariamatos theeffectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT gemmagutierrez theeffectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT karolinaostbring theeffectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT ceciliaahlstrom effectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT johanthuvander effectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT marilynrayner effectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT mariamatos effectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT gemmagutierrez effectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake AT karolinaostbring effectofprecipitationphonproteinrecoveryyieldandemulsifyingpropertiesintheextractionofproteinfromcoldpressedrapeseedpresscake |