What is Freeze Drying?

Freeze-drying, or lyophilization, is a process of removing moisture from a product while preserving its structure and quality. It involves freezing the product and then reducing the pressure to allow the frozen water to sublimate directly into vapour. For more info on the Science behind freeze drying and why its useful, read our knowledge base article here.

What types of products can be freeze-dried?

A wide range of products can be freeze-dried, including fruits, vegetables, pharmaceuticals, biological samples, instant coffee, and more. It’s often used for heat-sensitive or perishable items. Take a look at our knowledge base for information on more applications.

How does freeze-drying differ from conventional drying methods?

Freeze-drying preserves the product’s structure, flavour, and nutritional content better than traditional drying methods like air drying or oven drying, which can often result in shrinkage, loss of colour, or degradation of nutrients. See our “Freeze Drying Vs Dehydration” video here.

What are the advantages of freeze-drying?

Advantages include long shelf life, minimal loss of product quality, and the ability to store products at room temperature without the need for refrigeration.

Does freeze-drying alter the nutritional content of foods?

Freeze-drying preserves the nutritional content of foods better than other drying methods, with minimal loss of vitamins and minerals. View our video in this knowledge base article on ‘Freeze-drying Food” here.

What is the primary mechanism involved in freeze-drying?

The primary mechanism is sublimation, where frozen water transitions directly from a solid to a vapor state without passing through the liquid phase, due to reduced pressure and controlled heat input.

What is the role of the vacuum pump in freeze-drying?

The vacuum pump is essential for creating and maintaining the low pressure within the freeze-drying chamber, which allows sublimation to occur. The vacuum pump does not “suck” the water from the product and running the vacuum at too low a pressure can slow down the process.

What are some common techniques for measuring product dryness during freeze-drying?

Techniques include monitoring the product’s weight loss, measuring residual moisture content using techniques like Karl Fischer titration, and assessing the product’s physical characteristics.

Can you explain the role of the condenser in freeze-drying?

The condenser is responsible for trapping the water vapor sublimated from the product, preventing it from re-entering the product or the vacuum pump. This helps maintain the vacuum in the chamber.

Can freeze-drying be used for heat-sensitive biological materials?

Yes, freeze-drying is commonly used for preserving biological materials like proteins, enzymes, and vaccines, as it minimizes heat exposure.

How many trays are included with the CryoDry CD8?

The CryoDry CD8 comes with 5 trays as standard. Additional trays can be purchased through your local distributor or direct from CryoDry.

Can you change the number of shelves in the CryoDry CD8?

Yes. As standard the CryoDry CD8 come with 5 shelves additional shelf stack are available for purchase giving 9,7,3 or 1 shelves.

How easy is it to change the shelf configuration?

Changing the shelf configuration is a very simple procedure and only takes a couple of minutes. Open the door and pull out the existing shelf stack. Unplug the connector between the shelf stack and the condenser. Fitting a new shelf stack is the reverse of this procedure. For more information check the YouTube video and article here.

Do I need to swap oil in the vacuum pump?

As standard CryoDry offers the PSP12 Scroll pump which is an oil free pump, so no need to change oil. Learn about the benefits of our PSP12 Scroll pump here

How often do I need to service the PSP12 Scroll Pump?

The scroll pump requires a yearly service which consists of a clean and tip seal replacement. This can be carried out by your local distributor. For more information check the YouTube video in our knowledge base article here.

Can I get local repairs and service?

You can get local support from the dealer you purchased the unit from. Alternatively you can contact our support team by clicking Service Support

In our university, we have a shared manifold freeze dryer that serves multiple users. Is it possible to utilize the CryoDry CD8 as a freeze dryer for shared use?

Yes, the CryoDry CD8 can indeed be used as a shared freeze dryer. However, to accommodate multiple users, the unit will need to be operated in manual mode. When adding additional samples, please follow these steps:

  1. Ensure that any additional samples you wish to load are pre-frozen.
  2. To load these pre-frozen samples, begin by turning off the vacuum pump.
  3. Release the pressure by opening the drain valve.
  4. Add your sample to the freeze dryer chamber.
  5. Close the drain valve securely.
  6. Finally, turn the vacuum pump back on to resume the freeze-drying process.

This procedure allows for the safe and efficient use of the CryoDry CD8 as a shared freeze dryer while maintaining the quality of the samples.