Process Optimization of Almond Protein Extraction by Reverse Micelles and Comparison of Its Physicochemical Properties
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
Almond protein was extracted by a reverse micelle system constructed using AOT as the surfactant. Singlefactor experiments were conducted on the first and second extraction processes to study their effects. Based on this, response surface optimization experiments were performed on the first extraction process. The optimal parameters for the first extraction are as follows: a solid to liquid mass ratio of 1:15, an AOT mass concentration of 0.11 g/mL, a temperature level of 41 ℃, and a pH value of 7.0. For the second extraction, the optimal conditions are as follows: a KCl concentration of 0.5 mol/L, a temperature level of 45 ℃, and a pH value of 8.0 for the new aqueous phase. Under these conditions, the almond protein extraction rate of the first and second extraction processes reaches 67.37% and 66.50%, respectively. The physical and chemical properties indicate that emulsifiability and foamability initially increase and then decrease as the temperature rises within the range of 20 to 100 ℃, while they decrease slowly and then increase continuously as the pH value increases from 3.0 to 9.0. The emulsifiability and foamability of the extracted almond protein are optimal at 40 ℃ and pH 9.0. More specifically, the emulsifiability reaches 48.93 m2/g and 60.22 m2/g, respectively, whereas the foamability reaches 75.70% and 88.05%, respectively. These results differ from the effects of temperature on surface hydrophobicity, as the highest surface hydrophobicity is observed at 80 ℃. Antioxidant activity analysis revealed that almond protein exhibits stronger scavenging ability against ABTS compared to DPPH. Other properties, including solubility (74.84%), water holding capacity (4.34 g/g), and oil holding capacity (5.77 g/g), are favorable. In conclusion, applying the reverse micelle method for almond protein extraction is beneficial in obtaining high-quality almond protein, and the above finding provide a scientific basis for the application of this method in almond protein extraction.
