Enhancing zein functionality through sequential limited Alcalase hydrolysis and transglutaminase treatment:...

Area of Science:

• Food Science
• Biochemistry
• Protein Chemistry

Background:

• Zein, a major storage protein in corn, has limited solubility and functional properties.
• Enzymatic hydrolysis and protein conjugation are strategies to improve protein functionality.

Purpose of the Study:

• To investigate the impact of sequential enzymatic hydrolysis (Alcalase) and transglutaminase conjugation on zein's structure and functional properties.
• To determine the optimal degree of hydrolysis for specific functional improvements.

Main Methods:

• Sequential enzymatic hydrolysis of zein using Alcalase.
• Transglutaminase conjugation of zein hydrolysates.
• Analysis of secondary/tertiary structures (FTIR), hydrophobicity, free amine content, protein-protein interactions, emulsifying activity, solubility, foam capacity, and water holding capacity.

Main Results:

• Significant changes in secondary structure (decreased α-helix, increased β-turns) observed at higher hydrolysis degrees.
• Optimal emulsifying activity (65.96 m²/g) at 2% hydrolysis.
• Highest solubility (75.06%) achieved at 5% hydrolysis.
• Zein hydrolysate (7% hydrolysis) with transglutaminase showed improved hydrophobicity (H₀: 2992.33), foam capacity (65.95%), and solubilized protein (31.35%).
• Native zein with transglutaminase exhibited the highest water holding capacity (4.47 g/g).

Conclusions:

• Combined enzymatic treatment effectively modifies zein's structure and enhances its functional properties.
• This approach offers a promising strategy for improving zein's utility in plant-based food systems.
• Specific functional properties can be tailored by controlling the degree of hydrolysis and enzymatic treatment.