1. Processes

Freeze drying is a 3-step process. It involves selecting the type of food that you want to dry and freezing it. Next, the food is placed in a strong vacuum Here, the ice crystals in the food sublimate turn directly into water vapor rather than passing through the liquid state.

The food is then placed in vacuum storage bags or containers and stored either in a freezer, pantry or in an emergency kit when prepping.

On the other hand, dehydration involves using heat, dry air, and air movement to remove water from food. Dehydration can be done with or without a dehydrator.

2. Nutrition

Of course, the first consideration that should top your checklist is how good each of these methods preserves the nutrients in your food.

Freeze-drying has the upper hand at this front. Researchers suggest that since freeze-drying food involves removing up to 98% of the food’s water without the use of heat, the food tends to maintain a significantly higher nutrient content compared to dehydration.

On the other hand, dehydration is known for leading to a higher loss of nutrients. This could be attributed to the fact that this process involves subjecting the nutrients to high heat (up to 140℉) and light.

3. Taste

Having seen that some vitamins and minerals are stripped when dehydrating than during freeze-drying, it’s pretty much obvious that freeze-dried food tastes great.

Freeze-drying removes water only. Since it does not involve heating, the nutrients, flavors, and color of the food are left intact and remain so for quite a long time with proper storage.

4. Use Of Additives

Another major difference between freeze dried and dehydrated methods is the use of additives. If you are fond of buying dehydrated food from stores, then you must have realized that they have very high sugar contents. This sugary taste comes from the preservatives added during storage to extend the food’s shelf life.

5. Texture

This is where dehydrated foods beat their freeze-dried alternatives. Freeze-dried food has most of its water content removed. Dehydrated food, however, has a considerable amount of its water content sealed in.

As a result, dehydrated foods have a chewy texture and are sweet in taste. Unfortunately, remember that their taste slightly differs from that of fresh food due to the sugar, salt, and other preservatives used.

On the other hand, freeze-dried food tends to have a crispier and crunchy texture since they are virtually dry.

6. Variety

People are coming up with ways to freeze dry or dehydrate different types of food each day. However, it’s undeniable that freeze-drying offers a lot of options than any other food preservation method.

Freeze-drying allows you to use almost all foods ranging from high-water content to low-water content varieties. This means that you can freeze-dry not only herbs but yogurt, ice cream, cheese and fruits among others.

7. Rehydration

Regardless of the method that you go for, you’ll want to rehydrate your food before consuming it. Freeze-dried foods are much easier to rehydrate than dehydrated foods. The best part about rehydrated freeze-dried food is that it’s almost similar to fresh food in all aspects. These foods also rehydrate easily and only require water (hot or cold).

Dehydrated foods are another story. These foods can be really tough and this means that rehydration won’t be a walk in the park.

While cold water can still be used to rehydrate dehydrated foods, hot water is most preferred since it speeds up the process. 

While the use of hot water seems more promising, it might be a huge problem during emergencies and when you are far from civilization.

8. Cooking And Baking

Basically, both freeze-dried and dehydrated foods can be rehydrated and be used in a variety of dishes. All in all, freeze-dried food offer more options in that, they don’t vary much from fresh foods upon rehydration.

Dehydrated foods, on the other hand, remain very different from fresh their fresh food derivatives. This means that the two don’t deliver the same results. You could be limited to certain dishes due to this reason.

9. Shelf Life

Freeze-dried foods still take the lead here. Dehydrated foods contain between 30-50% of their water content compared to the 2% water content in freeze-dried foods.

What this means is that while these two methods aim at extending your food’s shelf-life, dehydrated foods are more susceptible to microbial growth than freeze-dried foods.

That being said, you should expect the latter to last for much longer. In fact, experts say that freeze-dried foods could be stored indefinitely if is stored in a free-standing freezer at zero degrees Fahrenheit.

This is subjective though. Whether you are dealing with dehydrated or freeze-dried foods, minute leaks in the packaging bags, cans, or jars could lead to bacterial growth even without causing any color changes on the package. Therefore, proper care is required irrespective of the method of preservation that you go with.

10. Cost And Efficiency

Freeze-drying your food seems like the best way of preserving food until you consider the cost. This method is usually quite costly especially in terms of power. Store-bought freeze-dried foods are also considerably costlier than their dehydrated alternatives.

In addition, these units don’t require so much power to run. Thus, you could save hundreds by dehydrating lots of food for usage when the supply is low.

Worth mentioning, however, is that dehydration can be time-consuming. This depends on the method of dehydration that you are using and the size of your family.

All in all, considering most of the other factors, freeze-drying stands out in terms of efficiency and speed. The key benefit here is that there is less waste credit to the long shelf-life of the foods. In addition, most freeze-dried foods can be added to virtually any dish that requires freshness.