Integrated Enzyme- and Ultrasound-Assisted Extraction of Fennel Seed Proteins: Process Optimization, Structure, and...

Area of Science:

• Food Science
• Biotechnology
• Protein Chemistry

Background:

• Fennel seeds are a potential source of plant-based proteins.
• Traditional protein extraction methods can be time-consuming and less efficient.
• Optimizing extraction techniques is crucial for maximizing yield and functionality.

Purpose of the Study:

• To develop an integrated enzyme-assisted and ultrasound-assisted extraction method for fennel seed proteins.
• To optimize enzymatic pretreatment conditions for enhanced protein yield and cell wall degradation.
• To evaluate the functional properties and structural integrity of the extracted protein isolates.

Main Methods:

• Enzymatic pretreatment optimized for pH, temperature, enzyme dosage, and time.
• Ultrasound-assisted extraction (UAE) as an alternative to alkaline extraction.
• Functional property analysis (solubility, emulsifying, foaming, water/oil holding).
• Molecular weight profiling (SDS-PAGE), FT-IR spectroscopy, and differential scanning calorimetry (DSC).

Main Results:

• Optimized enzymatic pretreatment (pH 4.20, 48.95°C, 1.91 FBGU/g, 2.60 h) increased protein yield to ~92%.
• Ultrasound-assisted extraction achieved ~93% yield in just 10 minutes.
• Enzyme-ultrasound treated isolates showed improved solubility, emulsifying, foaming, and water/oil holding capacities.
• Treatments preserved protein integrity while enhancing thermal stability (denaturation temperature increased to 176.23°C).

Conclusions:

• The combined enzyme-ultrasound method is effective and sustainable for producing functional fennel seed protein isolates.
• This approach offers a significant improvement over traditional methods in terms of efficiency and yield.
• The resulting protein isolates possess desirable nutritional and functional properties for food industry applications.