Modification of structure and functionalities of ginkgo seed proteins by pH-shifting treatment

Weiwei Zhang; Changqi Liu; Jing Zhao; Tianyi Ma; Zhendong He; Meigui Huang; Yaosong Wang

doi:10.1016/j.foodchem.2021.129862

Modification of structure and functionalities of ginkgo seed proteins by pH-shifting treatment

Food Chem. 2021 Oct 1:358:129862. doi: 10.1016/j.foodchem.2021.129862. Epub 2021 Apr 20.

Authors

Weiwei Zhang¹, Changqi Liu², Jing Zhao³, Tianyi Ma¹, Zhendong He¹, Meigui Huang¹, Yaosong Wang⁴

Affiliations

¹ Department of Food Science and Engineering, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, China.
² School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.
³ School of Kinesiology, Nutrition, and Food Science, California State University, Los Angeles, CA 90032, USA.
⁴ Department of Food Science and Engineering, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, China. Electronic address: yaosongwang@njfu.edu.cn.

PMID: 33940296
DOI: 10.1016/j.foodchem.2021.129862

Abstract

Modification and improvement of protein functionalities are important for expanding the applications of proteins in food. The objective of this study was to investigate the effects of pH-shifting treatments on the structural and functional properties of ginkgo seed protein isolate (GSPI). GSPI was exposed to acidic (pH 2.0-4.0) and basic (pH 10.0-12.0) pHs for 0, 0.5, 1, 2, and 4 h and subsequently neutralized for refolding. The pH-shifting treatments significantly increased GSPI solubility by 43-141% except for the treatment at pH 2.0, which decreased protein solubility by 16-39%. All pH-shifting treatments more than doubled the surface hydrophobicity of GSPI and significantly improved the emulsifying activity. The highest emulsifying activity was observed in the pH 2.0-treated GSPI, which was 4.9-fold higher than the control. Acid-induced GSPI degradation likely promoted protein adsorption to the oil-water interface. In summary, the pH-shifting-modified GSPI may serve as a promising emulsifier in various food systems.

Keywords: Emulsifying properties; Ginkgo seed proteins; Solubility; pH-shifting.

MeSH terms

Adsorption
Emulsifying Agents / chemistry*
Emulsions / chemistry
Ginkgo biloba / chemistry*
Hydrogen-Ion Concentration
Hydrophobic and Hydrophilic Interactions
Particle Size
Plant Proteins / chemistry*
Proteolysis
Seeds / chemistry
Solubility

Substances

Emulsifying Agents
Emulsions
Plant Proteins