Freeze-drying of lactic acid bacteria.

Area of Science:

• Food Science & Technology
• Microbiology
• Biotechnology

Background:

• Lactic acid bacteria (LAB) are vital for food production (yogurt, cheese) and probiotics.
• Freeze-drying (lyophilization) is a key preservation technique for LAB, ensuring long-term stability.
• Effective LAB preservation is essential for industrial applications and green chemistry.

Purpose of the Study:

• To present a pilot-scale freeze-drying method for lactic acid bacteria.
• To detail process parameters for maximizing bacterial survival and functionality.
• To enable controlled, large-scale preservation of LAB.

Main Methods:

• Bacterial suspension stabilization with protectant solutions.
• Pilot-scale freeze-drying involving freezing, primary drying (sublimation), and secondary drying (desorption).
• Controlled manipulation of process parameters during lyophilization.

Main Results:

• Achieved low water activity (<0.2) for extended storage.
• Minimized loss of bacterial viability and functionality.
• Demonstrated feasibility of pilot-scale freeze-drying for LAB.

Conclusions:

• The described pilot-scale freeze-drying method effectively preserves lactic acid bacteria.
• Optimized process control enhances bacterial survival and functional recovery.
• This technique supports industrial-scale application and distribution of LAB.