Summary of the Advantages and Disadvantages of Mechanical Pressing for Microbial Oil Extraction
Advantages
1. Simple Operation
- Equipment (e.g., screw presses, hydraulic presses) has a straightforward structure, making it easy to operate and maintain.
- The process is simple, requiring no complex chemical reactions or large amounts of chemical reagents.
2. Low Cost
- Lower investment and operating costs (mainly electricity consumption, no need for organic solvents).
- Minimal maintenance expenses, suitable for small-scale enterprises or laboratories.
3. No Organic Solvents Required
- Solvent-free product ensures high safety, meeting standards for food and cosmetics industries.
- Environmentally friendly, avoiding solvent volatilization and associated pollution or health risks.
4. High Product Quality
- Preserves natural oil components (e.g., unsaturated fatty acids, vitamins), enhancing nutritional and functional value.
- Better retention of original flavor and color, making it ideal for high-end applications.
Disadvantages
1. Relatively Low Oil Yield
- Limited by microbial cell wall structure (e.g., algal cellulose walls) and oil content, with yields typically ranging from 10% to 60%.
- Process conditions (pressure, temperature, duration) affect extraction efficiency.
2. High Cell Disruption Requirements
- Insufficient disruption reduces yield, while excessive disruption leads to oil-cell debris mixing, complicating separation.
3. High Labor Intensity
- Requires manual intervention for feeding, equipment adjustment, and post-pressing separation (filtration, centrifugation), reducing efficiency and introducing variability.
4. Limited Production Efficiency
- Poor continuous production capability; prone to clogging or wear, requiring frequent maintenance.
- Small batch processing capacity necessitates multiple units for large-scale production, increasing costs and space requirements.
Conclusion: Mechanical pressing is suitable for small-scale, low-cost, and eco-friendly applications, but its oil yield and production efficiency limit its use in industrial-scale operations.
