The growing need to make your food last longer has led to the adoption of different methods for food preservation. Two of such methods which yield proven results are dehydration and freeze drying. In this article, we will compare these two methods of removing moisture from your food in detail.
Dehydration with the help of heat is already a very popular method and it is well-known worldwide. Our modern needs had paved the path for another less known but yet well prevalent dehydration method called freeze drying. Before going deeper into the processes let’s have an overview of each of the processes:
Overview
Food Dehydration:
Food Dehydration in general terms is drying food by heat dissipation at high temperature. The water content of the food is removed by supplying heat to the food in enclosed container. This helps in drying the food and preserving it for long period of time. Portable dehydrators are commonly used at home which helps in dehydrating food.
Freeze Drying:
Freeze-drying (also called lyophilization or cryodesiccation) is the process in which food is frozen with the help very low temperatures. Food is then kept in a vacuum chamber and moisture is removed. Sublimation process is used in freeze-drying where the water content is directly converted from solid phase into the gaseous phase.
Let’s delve deeper into the topic and know the basic difference between the two processes and how essentially it impacts your food.
The Differences Between Dehydration vs Freeze Drying
1) Food Taste:
The food being dried can be made tastier by adding seasonings to eat when the process of drying takes place in a food dehydrator, while in freeze drying seasonings are not usually preferred and the food itself retains its original flavor. You can try different seasoning and flavors available in market for the dehydrated food
2) Process Complexity:
Freeze-drying is a complex process which requires industrial scale machines that are not only expensive but also needs operational expertise and occupies huge space making it very difficult to perform at home. While in the dehydration process you can easily dry foods items with the help of portable dehydrators which are both user-friendly and economical.
You can easily buy a dehydrator which suits your needs easily from the technologically advanced market space which offers an array of features to their users and start dehydrating the fruits and vegetables you like the most.
3) Rehydration:
The dehydration process requires the user to can add water to rehydrate the dried food but with a little more effort consumption, for instance, the dehydrated food should be boiled in water for optimum time length to restore the moisture content.
In freeze-drying, the moisture content of the dried food can easily be restored with little effort, for instance by just simply adding water and soaking the fruit or vegetables in it for some time. The fruit or vegetable pieces retain their original shape easily with minimal visible deformations.
4) Food Cell Structure:
The food cell structure remains intact in freeze drying process while in dehydration the food cell structure gets changed. As the cells of the fruit loose moisture, the cell shape gets shriveled and the fruit or vegetable being dried shrinks and get a little de-shaped in dehydration.
Foods dried by both the processes will have a different physical appearance. Freeze dried food looks fresher in appearance and more closely resembles the original shape.
5) Nutritional Value:
Freeze dried food has more nutrition value as compare to the dehydrated food. Some of the vitamins are lost in the process of dehydration while in freeze-drying most of the vitamins are retained. However, the dehydrated food is still rich in carbohydrates and fiber.
6) Shelf Life and Storage:
The shelf life of freeze-dried food is longer as compare to the dehydrated food. This is because of the simple reason that freeze drying removes almost 100% moisture from the food while dehydration removes more than 90% of the moisture content of the food being dehydrated.
Thereby, lower the moisture content lesser are the chance of food spoilage. The dehydrated food needs to be stored properly is airtight containers, while freeze dried food should be preferably stored at the temperature of 75 degrees F or lower.
7) Cost:
The cost of dehydrators available in the market is very less as compared to freeze drying equipment. Normally, freeze drying process is done commercially with the help of freeze drying equipment/machines.
8) Effort and Expertise:
Freeze Drying requires additional effort and operational expertise while you can dry foods easily in a dehydrator as they are user-friendly. Normally, machines available in the market for freeze-drying are of industrial use. Programmable dehydrators are available in the market which requires very less monitoring as they have features like timer, thermostat etc.
9) Space:
Space occupied by dehydrated food is less than freeze dried food as the food pieces are thinner because of less moisture content. You can carry more food with yourself if you’re going on a long trip or you can to store more food in smaller packets.
Comparative Video Guide:
Conclusion
After going through both the process in depth we conclude that the nutritional value of the freeze dried food is superior to the dehydrated food as freeze drying prevents the enzymes from getting denatured at high temperatures and prevents vitamin losses for instance loss of vitamin C from citrus fruits as in the case of dehydration.
However, dehydration is a great and a healthy way to dry food items at home and retains maximum nutrients like carbohydrates and fibers in the food. Additionally, there are high chances of you not being able to find your favorite freeze-dried food – fruit, vegetable or meat commercially available in stores. Having a dehydrator at home equips you a plethora of choices to dry a range of different food items as per your wish.
Moreover, as discussed, dehydrators come in different price ranges and are portable. This gives the user the feature to budget flexibility and allows you to have your own dehydrator instead of spending a huge amount of money on store bought dried food.
Freezing v. dehydration
I use both.
Both have totally different attributes.