Effective Ethyl Carbamate Prevention in Red Wines by Treatment with Immobilized Acid Urease

Area of Science:

• Enology
• Food Chemistry
• Biotechnology

Background:

• Climate change presents challenges for the wine industry, increasing risks from chemical food contaminants like biogenic amines and ethyl carbamate (EC).
• Ethyl carbamate (EC) is a potential carcinogen that can form in wine during storage, influenced by precursor compounds like urea.
• Controlling EC formation is crucial for wine safety and quality.

Purpose of the Study:

• To investigate the efficacy of immobilized acid urease for urea removal in red wines.
• To assess the impact of urea reduction on ethyl carbamate (EC) formation during wine storage.
• To model the kinetics of urea removal using immobilized urease in batch reactors.

Main Methods:

• Red wine was treated with immobilized acid urease to remove urea.
• The study employed separable kinetics to model catalyst deactivation and urea hydrolysis.
• Urea concentration and potential ethyl carbamate (PEC) levels were monitored over time in repeated batch reactor uses.

Main Results:

• Immobilized urease treatment reduced urea concentration in red wine from 30 mg/L to approximately 0.5 mg/L within 28.5 hours.
• This reduction led to a significant decrease in potential ethyl carbamate (PEC) from 1662 μg/L to 93 μg/L.
• The immobilized enzyme demonstrated superior efficiency compared to free urease, achieving lower contaminant levels in less time.

Conclusions:

• Urease immobilization is a highly effective strategy for urea removal in red wines.
• This method significantly reduces the formation of ethyl carbamate (EC), a key process contaminant.
• The findings support the potential for industrial-scale application of immobilized urease for wine safety.