Dehydrated Foods and Freeze Dried Foods- By chef Raman

Dehydrated Foods and Freeze Dried Foods- By chef Raman


Are you wondering what the differences are between freeze dried foods and dehydrated foods? 


There are a number of differences:- 


First of all, the processes used to preserve the food and prevent spoilage and enzymatic breakdown are very different. Other factors you may want to consider are cost, shelf life, taste, texture, and nutritional value.

Dehydration removes moisture from the food by the circulation of hot dry air. The water evaporates. This prevents the growth of microorganisms. Oxygen, heat, light, and moisture all contribute to the breakdown of nutrients and spoilage of food. Due to the use of heat, some of the nutritional value will be lost. Using an electric dehydrator will preserve more nutrients than some of the other methods of dehydration. Dehydrated food is light and generally less expensive than freeze dried food.

However, it does have more changes to texture, aroma, taste, and nutritional value. It can have a shelf life of up to twelve years when stored properly. Re-hydration time is generally up to 20 minutes in boiling water and can be up to two hours in cold water.

Freeze drying removes water from the food by 

sublimation. 

The food is sealed in a vacuum chamber which forces the air out. Freeze drying uses temperatures between -50 degrees Celsius and -80 degrees Celsius. This vaporizes the ice. Because of this, freeze dried food retains more nutrients, and much of its original aroma, texture, and flavor. Freeze dried food is light and usually more expensive than dehydrated food. The process can take several days and the equipment is expensive.

Freeze dried food has a longer shelf life than dehydrated food because up to 98 percent of the moisture is removed. The shelf life can be up to twenty five years when stored properly. Re-hydration time is generally 5 minutes in hot water and up to 10 minutes in cool water.


Dehydrated and freeze dried foods are great for back packing as they are light and easy to prepare. They are both excellent for long term food storage. Both reduce the waste of throwing away fresh produce that has spoiled. However, if nutritional value and taste are a top priority for you then I would recommend choosing freeze dried foods over dehydrated foods. The flavor, texture, and aroma win every time.