LPT 321: Meat Science (1+1)

FREEZE DRYING OR LYOPHILIZATION

• This is the process of removing water from frozen foods.
• The removal of water is accomplished by sublimation, i.e the water in the frozen meat evaporates without melting of ice.
• Frozen meat is subjected to controlled vacuum and temperature conditions to accomplish the removal of water, by sublimation.
• The food product must be in comminuted form (sliced or diced) and packaging must be completely moisture proof since, the dried products are hygroscopic.
• This process can preserve beef, pork, chicken and shellfish.
• Whole steaks and chops can be freeze dried.
• Since, meat has high moisture content, it is expensive to preserve meat by lyophilization.
• The advantages of lyophilization are shrinkage and distortion of shape are very minimal, and retention of flavour and nutrition is excellent.