FOOD & COOKING

How to Freeze Dry Food: Guide To Your Lightweight Meal in Nature

how to freeze dry food
John C. Porter
Written by John C. Porter

Camping in the great outdoors is great, but it’s not always easy to pack all the food you need, right? The best way to deal with this without getting the whole fridge with you is to learn how to freeze dry food. However, the process of freeze drying the food is not a simple thing and you’ll need to learn a thing or two about it.

Freeze dried food is an option that will provide you with more calories and nutrition than regular food on your trips. Freeze dried food is more lightweight and compact and with it, easier to be carried in a backpack. On top of everything, preparing it is very easy, it doesn’t take much time and you don’t need some special tools.

Since the freeze dry food is proven to be the best option when it comes to packing food for longer period of time, you’ll need to learn everything there is about this process. In this article, we’ll tell you everything you need to know about it and at the end, you’ll feel like an expert in the field of freezing dry food. Read on to see how to never stay hungry in nature again.

What Freezing Dry Food Actually Means

The process of freeze drying food for the purpose of later consuming of it is actually removing the water from the food and leaving only the useful ingredients that you need. Since there is no logic in dragging a pound of bananas in nature, this is the way that you’ll save weight, space, time to prepare the food and yet, you’ll be full all the time.

dried fruit in mason jars

The process for the food to be ready though takes some time. All good things in life need time to be done, right? Well, this is just one of them. Sure you can buy one of those heavy expensive machines that suck out the water from the food in no-time, but why? If you’re in a hurry, buy some already frozen dried food from the store, and prepare better for your next adventure.

The Difference Between Freeze Dried Food and Dehydration

Many people don’t know there is a difference between the two of these processes, but there is a great difference. Even though they both extract the water out of the food, the method is different and many people are not aware of it. Here’s a short explanation of this, just in case you’re one of them that think this is the same thing.

The main and most important difference between these two methods of handling food is the amount of water they extract and the type of food they provide after the process. The dehydration process is somewhat easier to do, but the freeze-drying gives you a better deal.

When it comes to extracting water, you get about 95% of the liquids out the food with dehydration and about 98-99% with freeze drying. However, this is not as important as the fact that after you’re done, you can’t reverse the process and, for example, get whole vegetables again with the dehydration method.

tomatoes in food dehydrator

Your food with it stays crunchy and lost the shape it used to have forever. Yes, the nutrition is still in there, but not all. Some foods lose up to half of the important things that were in the food with the dehydration. Also, the shelf life is really shorter – at least three times shorter.

How Both Methods Work

Both methods drain the water out of the food but with different methods. The freeze drying, like we will explain in bigger detail later on, uses low temperatures to take the water out, while dehydration uses high temperatures. When it comes to dehydrating, in short, it looks like this – you cut the vegetables or fruits in half, or in slices, you place them in a tray and put them in the oven.

Then, set the temperature on the lowest level and let them like that for at least 6 hours. There are machines that dehydrate food for an extremely fast period of time, but they are not essential for this process – food can be dehydrated without a machine.

Why Make Freeze Dried Food

Well, it’s not always easy and simple to carry a whole backpack just with food. Some trips can last longer, sometimes the adventurer goes on camping trips for more than a week and must be equipped with everything. That means carrying a lot of weight, and prepared food is not lightweight at all.

dried fruit and nuts in ziploc.png

But, when you freeze dry the food, everything is lighter up to 10 times. A normal freeze-drying process will cut the weight more than 5 times on some foods. Foods with more water are usually the ones that will lose the most weight – those that are not rich in liquids will remain more or less heavy.

How to Freeze Dry Food

It is quite simple really, you take the food you like to take camping and you put it in the freezer. That’s it – the rest it on the mother nature and the freezing temperatures of your freezer. So why waste more words on it, you’d ask? Because there are tricks on how to do it better. Want to know some of them? Follow up and see!

What Food is Best For Freeze Drying

We’ve already mentioned that the process of freeze dry food is taking the moisture out of it. So based on this, the best foods are those that contain more water. Fruits and vegetables that contain lots of liquids are the best – grapes, apples, strawberries, oranges, bananas, carrots, tomatoes, peas, avocados, etc.

Everything that is filled with water is the best, but it doesn’t mean that this is the only thing you can freeze dry. Meats, pasta, even full dishes can be freeze-dried.

freeze dried food

However, if you’re about to go camping, you’re surely not thinking about lobster in a special sauce – it’s more about food that will keep you full and give you strength to continue your journey.

What Food is Not Suitable For Freeze Drying

Well, it would be logical to say that foods with less water are not suitable for freeze drying, right? Meat might be full of nutrition, calories and everything you need to stay in shape, but after you freeze dry it, it’s not as great as it would be on your kitchen table.

However, if you’re aware of the fact that your frozen and unfrozen food can’t be the same, then cooking and freezing meat is just okay.

What You Need to Know About The Freeze Drying Process

Even though the process seems pretty simple, there are some things you need to know. First of all, the food that you’re about to take camping – you place in the freezer. The deep freeze is the best option, but it’s not absolutely necessary.

packing freezed dried food

Make sure it is the only food in the freezer so the water that is extracted from one food doesn’t mix with others. The freezing process is pretty fast, in a matter of hours your food will be frozen.

If you want to check how the process is going, open the freezer door after a few hours, because frequent opening will only slow it down and you’ll need to wait for longer. When the food is ready, you’ll place it fast in a vacuum and leave it like that at least a week.

How to Know if the Food is Ready

The food stays in the freezer for at least several hours, and this depends on the type of food and the strength of the freezer. It must pass at least 3-4 hours before it’s really ready. When that’s over, place the food in a vacuum and leave it there at least a week but preferably, around a month. Foods with more water are harder to dry, so keep that in mind.

After several weeks in special conditions, 120 torrs and a temperature of 50 F degrees, your food is almost ready to be eaten. When you take it out, you’ll see that the food is exactly like you placed it inside, practically intact, but it seems like there is no water in it. It’s dried.

freeze dried pickles

When you’ve reached this point, you simply take the food and seal it in special bags that you will later take on your journey. When the time comes to eat your freeze dried food, there is nothing easier in this world – you just feel a bowl of water and you place the food inside. The food then absorbs the water from it and comes back in its original shape and texture.

You Don’t Really Need a Vacuum Chamber

The best is to place the frozen food in a vacuum chamber, but the whole process will happen even without it. Simply place the food on a tray, or something that won’t be used for weeks, and leave it like that in the freezer. Nature will do the rest.

After several weeks, take one of the fruits, for example, or part of the food you’re freeze drying, leave it to get the room temperature and open it in half.

freeze drying strawberries

If the food is black or dark, then the process is not over yet. Leave it another week and then try the same all over again. The freeze-dried food that has gone through the whole process and finished successfully, doesn’t change the original color.

Freeze Drying With Dry Ice

A method to fast freeze dry your food is the dry ice method. It works thanks to the dried ice that keeps the temperature below freezing point, but it evaporates in time. As it evaporates, it takes the other liquids of the food you like too. When the dry ice is gone, the process is finished.

The preparation is almost the same as for the longer and natural version. You freeze the food and place it in the container filled with dry ice. Remember that it will constantly turn into gas and you’ll see how it’s going. But, if you place something over the container, the process will be slowed down and even be unsuccessful.

dry ice in container

Leave it unsealed and after 24 hours, you’ll have your food ready. It’s important to mention that 10 pounds of food will require the same amount of dry ice, so make sure you have a large enough container. Also, make sure the weather conditions are good – meaning the atmospheric moisture is at lower levels. If it rains outside, the process will take much longer.

Freeze Drying in a Machine

If you have some extra 2 or 3 grand, and for some machines even more, then you can forget about this whole process. There is nothing more simple than freeze drying your food in a machine made for this.

Every type has its own description manual that you’ll need to read, but basically, you place the food in the machine, and take it out after nine hours or similar, depending on the strength of the machine.

Take Caution Measures

Always wear gloves that can hold low-level temperatures. The ice will make serious damages to your fingers if you touch the tray with bare hands. Especially if you choose the dried ice method, you will need a special kind of insulated gloves that will protect you the most.

yellow rubber gloves

Another important thing when it comes to freeze drying food is to make sure the temperature is really freezing. Some foods that are left on temperature over 32 F degrees might get rotten and inedible. Plus, food that is getting spoiled smells awful, so you don’t want to deal that kind of stuff.

The Bad Side of Freeze Drying Food

First of all, preparing it means you will lose the freezer for some time. Unless you own a machine, then the process will occupy your freezer. Of course, you can freeze dry just two apples, but what’s the point of this, right? You need food that will be enough for a longer period of time, that is the main reason you do the whole process.

Second, you can’t just prepare food and take it with you, unless you’re filthy rich or have a company that needs constant freeze dried food. It’s an expensive machine if you want to purchase one for this occasion. Sure you can go without it, but then it will cost you time, and some people value this more than money.

home freeze dryer

Finally, the size of the food won’t change after the process. What you see is what you’ll get in the wilderness, only more lightweight.

Sure, this is an excellent advantage, but you should be aware that the food won’t simply shrinks or become miniature. Of course, all this is nothing compared to the advantages, but a traveler should know all the details.

Final Thoughts – Get Your Apples Ready

The preps for camping are starting way before the camping day. All backpackers and campers know how important the food is, and making freeze dried food is the best option without a doubt. We say this to encourage you – you’re making the right choice with freeze drying foods.

freeze drying food in home freeze dryer

With freeze dried food you get ultralight backpacking and you’ll be able to travel without worrying about the heavy food, yet still have plenty of reserves for unexpected situations. You just need to give yourself some time before the trip and complete the freeze-drying process well.

Of course, if you get the freeze-drying machine, you’ll have this in no time, but we recommend to save your money. There is absolutely no need of it if you have enough time to prepare for the trip.

And before you get in the kitchen and start slicing, don’t forget to leave us a comment in the comment box section about your thoughts on the subject.

ABOUT THE AUTHOR

John C. Porter

John C. Porter

John is passionate about hiking long distances. His record is over 65 miles in one day with backpacking gear. John hiked over 10 thousand miles, tried over 100 hiking shoes and visited 56 countries so far. His favourite hiking route is West Coast Trail on Vancouver Island in British Columbia, Canada.