Freeze drying, also known as lyophilization, is widely regarded as a superior industrial drying and preservation method. By drying at lower pressure, boiling points are lowered which allows products to dried at lower temperatures compared to other methods. This reduces damage to the product and ensures cellular integrity is retained.

Perhaps the key benefit of freeze drying is that all cellular integrity is retained throughout the drying process. The only thing removed from the product is water. This means that products retain the following characteristics from when they're fresh to when they're dry:

Other benefits include the fact that vitamins and enzymes remain intact, shipping weight is significantly reduced and shelf-life is extended to over 2 years, providing suitable packaging is used. Reconstitution (rehydration) is almost instantaneous when water is added to the dried product.

General steps to successful freeze drying are as follows:

1.Freeze

Moisture is ‘locked’ into the product by freezing in a separate freezer.

NB: Difficult products can be frozen inside the Freeze Dryer. Shelf freezing reduces the shelf temperature in the chamber to -18°C or lower, but this adds to the processing time.

2.Load

Product is placed into a chamber, which is evacuated to low pressure. As a guide, atmospheric (sea level) pressure is 1017mBar, and the chamber is evacuated to around 1mBar before drying begins.

3.Dry

Energy is then gradually applied to the product over a period of 20-24 hours, although this varies depending on the product and loading. This heat (energy) causes the ice to sublimate – that is transform from ice to vapour without passing through the liquid phase. The water vapour is then attracted to the lower temperature ice coil where it condenses as ice.

4. Pack

Product is removed and packed in air tight sealed bags to prevent rehydration

Strictly speaking, anything can be freeze dried providing it contains water. Freeze drying is often used for food preservation and also for storing biologicals and pharmaceutical products. Examples include:

• Vegetables, meat and fish
• Fruits and juices
• Aloe vera, echinacea, and neutraceuticals
• Cultures for use in the dairy industry
• Water damaged books and documents
• Viruses and bacteria storage

Find out more about freeze drying applications.

We have a free guide to help you choose a freeze dry. To download this click our link - A Guide To Choosing A Freeze Dryer

Cuddon Freeze Dry's engineers will travel to your site to install and commission your freeze drying equipment.

At this point our engineers also train your staff to use the freeze drying equipment.

All Cuddon freeze dryers are fabricated from T304 stainless steel, include 2 sets of stainless steel product trays, shelf freezing to -20°C, shelf heating to +60°C, CIF freight, installation, commissioning and staff training.

We can quote a number of optional extras depending on your user requirements. A few common examples are as follows:

• Lower and higher shelf freezing/heating as required
• Tray trolley's for ease of handling
• SCADA data acquisition
• Air-cooled refrigeration condenser instead of water-cooled
• Cooling tower for refrigeration condenser
• Heat recovery system to allow for faster ice coil defrost time
• Inclusion of remote monitoring facility via modem
• IQ/OQ validation

Yes we can. Custom modifications can be built in during the manufacturing process. Upon confirmation of your order you’ll be required to submit a ‘User Requirement Form’ which outlines your requirements.

For New Zealand and Australia, delivery to site and taxes/duties are covered in the sale price.

For other countries, the customer is required to facilitate and pay for these components.