The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins
Rapeseed press cake (RPC), the by-product of rapeseed oil production, contains proteins with emulsifying properties, which can be used in food applications. Proteins from industrially produced RPC were extracted at pH 10.5 and precipitated at pH 3 (RPP3) and 6.5 (RPP6.5). Emulsions were formulated a...
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MDPI AG
2021-07-01
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| Series: | Foods |
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| Online Access: | https://www.mdpi.com/2304-8158/10/7/1657 |
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| author | Karolina Östbring María Matos Ali Marefati Cecilia Ahlström Gemma Gutiérrez |
| author_facet | Karolina Östbring María Matos Ali Marefati Cecilia Ahlström Gemma Gutiérrez |
| author_sort | Karolina Östbring |
| collection | DOAJ |
| description | Rapeseed press cake (RPC), the by-product of rapeseed oil production, contains proteins with emulsifying properties, which can be used in food applications. Proteins from industrially produced RPC were extracted at pH 10.5 and precipitated at pH 3 (RPP3) and 6.5 (RPP6.5). Emulsions were formulated at three different pHs (pH 3, 4.5, and 6) with soy lecithin as control, and were stored for six months at either 4 °C or 30 °C. Zeta potential and droplet size distribution were analyzed prior to incubation, and emulsion stability was assessed over time by a Turbiscan instrument. Soy lecithin had significantly larger zeta potential (−49 mV to 66 mV) than rapeseed protein (−19 mV to 20 mV). Rapeseed protein stabilized emulsions with smaller droplets at pH close to neutral, whereas soy lecithin was more efficient at lower pHs. Emulsions stabilized by rapeseed protein had higher stability during storage compared to emulsions prepared by soy lecithin. Precipitation pH during the protein extraction process had a strong impact on the emulsion stability. RPP3 stabilized emulsions with higher stability in pHs close to neutral, whereas the opposite was found for RPP6.5, which stabilized more stable emulsions in acidic conditions. Rapeseed proteins recovered from cold-pressed RPC could be a suitable natural emulsifier and precipitation pH can be used to monitor the stability in emulsions with different pHs. |
| first_indexed | 2024-03-10T09:39:00Z |
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| institution | Directory Open Access Journal |
| issn | 2304-8158 |
| language | English |
| last_indexed | 2024-03-10T09:39:00Z |
| publishDate | 2021-07-01 |
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| record_format | Article |
| series | Foods |
| spelling | doaj.art-2c79f66cfec94b829aea81d32b44bd3d2023-11-22T03:48:39ZengMDPI AGFoods2304-81582021-07-01107165710.3390/foods10071657The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed ProteinsKarolina Östbring0María Matos1Ali Marefati2Cecilia Ahlström3Gemma Gutiérrez4Department of Food Technology Engineering and Nutrition, Faculty of Engineering, Lund University, P.O. Box 124, 221 00 Lund, SwedenDepartment of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, SpainDepartment of Food Technology Engineering and Nutrition, Faculty of Engineering, Lund University, P.O. Box 124, 221 00 Lund, SwedenDepartment of Food Technology Engineering and Nutrition, Faculty of Engineering, Lund University, P.O. Box 124, 221 00 Lund, SwedenDepartment of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, SpainRapeseed press cake (RPC), the by-product of rapeseed oil production, contains proteins with emulsifying properties, which can be used in food applications. Proteins from industrially produced RPC were extracted at pH 10.5 and precipitated at pH 3 (RPP3) and 6.5 (RPP6.5). Emulsions were formulated at three different pHs (pH 3, 4.5, and 6) with soy lecithin as control, and were stored for six months at either 4 °C or 30 °C. Zeta potential and droplet size distribution were analyzed prior to incubation, and emulsion stability was assessed over time by a Turbiscan instrument. Soy lecithin had significantly larger zeta potential (−49 mV to 66 mV) than rapeseed protein (−19 mV to 20 mV). Rapeseed protein stabilized emulsions with smaller droplets at pH close to neutral, whereas soy lecithin was more efficient at lower pHs. Emulsions stabilized by rapeseed protein had higher stability during storage compared to emulsions prepared by soy lecithin. Precipitation pH during the protein extraction process had a strong impact on the emulsion stability. RPP3 stabilized emulsions with higher stability in pHs close to neutral, whereas the opposite was found for RPP6.5, which stabilized more stable emulsions in acidic conditions. Rapeseed proteins recovered from cold-pressed RPC could be a suitable natural emulsifier and precipitation pH can be used to monitor the stability in emulsions with different pHs.https://www.mdpi.com/2304-8158/10/7/1657rapeseed press cakecold-pressedemulsifying propertieszeta potentialturbiscanemulsion stability |
| spellingShingle | Karolina Östbring María Matos Ali Marefati Cecilia Ahlström Gemma Gutiérrez The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins Foods rapeseed press cake cold-pressed emulsifying properties zeta potential turbiscan emulsion stability |
| title | The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins |
| title_full | The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins |
| title_fullStr | The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins |
| title_full_unstemmed | The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins |
| title_short | The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins |
| title_sort | effect of ph and storage temperature on the stability of emulsions stabilized by rapeseed proteins |
| topic | rapeseed press cake cold-pressed emulsifying properties zeta potential turbiscan emulsion stability |
| url | https://www.mdpi.com/2304-8158/10/7/1657 |
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