What’s Freeze Drying?
Definition of Freeze Drying
Freeze drying, is a low temperature dehydration process, typically use to preserve perishable materials or make the material more convenient for storage.
The definition of freeze drying is to dry something in a solid state and is under vacuum environment.
How Freeze Drying Works?
Theory, Principle and Advantages
The theory of freeze drying is based on water triple point, that is: 3 phases of water (Vapor, Solid, Liquid) can flexibly convert, by change its surround pressure and temperature.
To achieve freeze drying, water in product should in solid phase(frozen), its surround pressure should be lower than water triple point.
Vacuum freeze drying is a sublimation process. It removes water by freezing the material, and then reduce its surrounding pressure to allow the frozen water in the material to sublime directly from solid phase to gas.
During the freeze drying process, most time, materials temperature is below zero. So, freeze drying has less impact on product chemical properties, which ensure the biological activity.
Differences Between Freeze Drying and Lyophilization
Lyophilization and freeze drying are synonymous. People call freeze drying or lyophilization depends on customary or the industry it taking place.
For example, food drying industry, people call freeze drying more, while in pharmaceutical or biological area, people call lyophilization instead.
Freeze Drying Working Steps?
Recipes Program and Time Chart
There are 3 main steps in freeze drying: Freezing, Primary Drying and Secondary Drying.
Freezing Stage. Materials completely frozen is the first step also is the insurance of a success lyophilization.
Primary Drying Stage. Remove physical water, as know, >90% water in raws are physical water, this stage takes quite long time.
Secondary Drying Stage. Remove bound water, bound water is hard to remove, this stage need ultra vacuum and higher Temp.
What’s A Freeze Dryer/ Lyophilizer?
Categories Of Freeze Dryers/Lyophilizers
Freeze dryers and lyophilizer machines are made to create all the necessary conditions that sublimation needs. As well as adjustable of itself working condition to execute freeze drying steps. Check Freeze Dryer Structure.
Based on production capacity, they can be divided into lab scale and production scale. Based on application field, they can be divided into pharmaceutical lyophilizers, food freeze dryers and general purpose freeze dryers.
Freeze Dryer/Drying Costs?
What Matters Freeze Drying
Freeze drying technology is very costly. The freeze drying equipment matters only 10% of its overall cost, 90% is its operation. A poor machine designing and a lack of productivity due to machine maintenance is going to cost you continuously.
Check Freeze Dryer/Drying Cost.
Freeze Drying Solutions
A freeze drying solution is not a freeze dryer model recommend. This is because freeze drying is very time costly and energy costly.
Purchase of a freeze dryer need consider: Application Feasibility, Supporting Facilities, Freeze Drying Batch Duration, Consumptions Of Water and Electric, Total Investment and Future Necessary Maintain/Labor Cost etc. Which need a comprehensive investigation to guarantee your freeze drying business is profitable.
In another word, when you purchase a freeze dryer, you are after supplier's service. Check Vikumer Freeze Drying Solutions.
What Product Can or Cannot Be Freeze Dried?
Products Can be Freeze Dried
- Food, Fruits, Vegetables, Meats, Dairy, Eggs, Meals, Coffee
- Pharmaceutical, Vaccines, Injectable Formulations, Serum, Penicillin
- Biological, Lactic acid bacteria, Probiotics, Plant Extracts.
- Chemical, Graphene, Earth
Products Can be Freeze Dried
- High fat, sugar and oil contain products not suit freeze drying. Like syrup, pure chocolate, pure honey and butter etc. is not easy to dry.
What’s The Differences Between Freeze Drying and Vacuum Drying?
The main difference between them is the water remove theory: Vacuum drying based on water boiling point, and vacuum freeze drying based on water melting point.
Read more the differences between freeze drying and vacuum drying.
Advantages of Freeze Drying and Lyophilization
Freeze drying is a low temperature dehydration method. During the process, most time, materials keep in minus temperature. So, freeze drying has less impact on product chemical properties, no ruin the biological activity, vitamin, flavor, taste and appearance.
Check Freeze Dried Samples.