Selecting a Freeze Drier on Amazon.com

Freeze driers, sometimes spelled freeze dryers, are used to preserve materials and specimens by removing moisture. Freeze drying equipment is used in food processing, pharmaceutical, and research settings to process samples for testing and long-term preservation. The process of freeze drying, called lyophilization, is a three-step process that works by exposing samples to temperatures below their freezing point. Because of this, it's important to know the freezing point of the substance and the temperature range of the freeze drying machine.

A freeze dryer's capability is determined by its condenser and shelf configuration. The condenser determines the lowest achievable temperature and the speed at which the condenser dries. Drying speed is an important factor for high-production applications. Shelf configuration is also an important consideration. Larger shelf sizes enable operators to process larger quantity of materials in one operation, while specific shelf configurations are available for bulk processing or processing test tubes, flasks, or stoppered materials. Note that recommended loads are always less than the stated capacity. For example, while the stated capacity of chamber might be six liters, the recommended capacity for might be only three liters.

The chamber material is usually composed of 304 stainless steel or 316SS stainless steel. The FDA requires 304 stainless steel when processing food-grade substances, while 316SS stainless steel is most often used when processing pharmaceuticals. While one freeze dry machine model might have the ability to perform automatic sterilization, other models require manual sterilization. Some digital models have digital displays and data output capability to ensure that samples are always kept within safe limits.

Factors to consider when selecting a freeze dryer include the available space, whether a benchtop or floor-standing model is required, regulatory compliance requirements, chamber material, freezing point of the material being processed, shelf configuration and capacity, automatic sterilization, and the proximity to a power, water, and air conditioning.