If you have a backyard homestead, you need to know how to preserve your hard-earned produce. And there are many food preservation methods to choose from. Freezing is one of the traditional ways to store food long-term. But when it comes to freezing food, which method is best: standard freezing or freeze-drying?
Freeze-drying removes almost all the water from food to preserve it, whereas regular freezing turns the water in food into ice. Overall, freeze-dried foods will last decades longer than food in the freezer. But to freeze dry food, you’ll need a freeze dryer.
Even though both methods use freezing to preserve food, scientifically they have totally different effects. So below, we’re going to look at 7 major differences between a freeze dryer and a freezer.
Difference #1: The Way Freezers and Freeze-Dryers Work
The main difference between a freezer and a freeze-dryer is the way they work. Freezing will often change the cellular structure of the food. Whereas a freeze dryer causes less damage by gradually drawing out the moisture from food.
Here’s How a Freezer Works
Modern-day freezers work on a system of coils, coolants, and science. Vapors are heated and cooled in an endless cycle. And the result is that heat is constantly pumped away from your freezer box to keep it at temperatures below freezing.
The concept of freezing food has been around for a very long time. Our earliest ancestors used ice and snow to preserve their food. But since the 1930’s we’ve been blessed to have modern freezers available in our homes.
Food is made up mostly of water. And when it’s frozen, harmful microorganisms can’t grow because they can’t feed off the frozen water, nor can they thrive. Worst case scenario, the microorganisms hibernate because it’s too cold for them. In a best-case scenario, the cold actually bursts them and they die. It depends on their cellular structure, but that’s a chat for another time.
Freezing also slows down the enzymes that would usually cause the food to spoil.
A good freezer should be at least 0 degrees Fahrenheit (-18 degrees centigrade). At this temperature, you can safely store some foods for up to a year. If the freezer is any warmer than this, you can’t safely store foods in it for as long.
Here’s How a Freeze Dryer Works
Freeze drying is different from freezing because not only does it freeze the food, but it also dries it out. Freeze drying will remove 98 to 99 percent of the moisture from the food. Yet at the same time, the food retains up to 97 percent of its original flavor, coloring, nutrition, and taste.
Although freeze-drying is new in our homes, its basic principles have been around for hundreds of years. Freeze drying really took off in the 1950s for food and medical preservation. And freeze-dried food became a staple for space missions and military operations.
To freeze dry food, you need to have a freeze dryer. And the process of freeze-drying happens in three stages within its vacuumed chamber. The first stage, known as the freezing stage, is where the food is frozen rapidly to -30 to -50 degrees. When the food is frozen quickly, the ice doesn’t have a chance to expand and break the structure of the food.
The next stage is known as sublimation. And this is when a bit of heat is added to the chamber. And because of the vacuum, the water in the food which is now ice turns directly into a vapor. Instead of becoming a liquid first.
The third stage of freeze-drying is known as Secondary drying or adsorption. This is when the temperature increases a little bit more. So, the remaining moisture is removed from the food.
The process of freeze-drying takes between 20 to 40 hours, depending on what food you’re using. Smaller items or portions will freeze-dry quicker than larger ones. And some foods such as meat will dry quicker than vegetables with high water content.
Want to read more about the science of how freeze dryers work? Read this article we wrote on it next: How Do Home Freeze Dryers Work? Science and Process Made Easy.
Difference #2: Food Quality
Taking into account how a freezer and freeze dryer work, the next big difference between the two is the quality of the food.
When food is frozen, the water inside it will expand and turn into ice. This can damage the cell walls of the food. So, this is why the texture and flavor of frozen food can change when it’s defrosted. As well as this, some dairy products will curdle in the freezer.
And when food isn’t stored properly in the freezer, it’s susceptible to freezer burn. This is when the cold air comes into contact with the surface of the food. Although food with freezer burn is safe to eat, usually it will affect the taste and texture. Freezer-burned food is almost always subpar when compared to the fresh version of the food.
One of the most appealing things about freeze-drying is that the food will retain almost all of its quality, taste, and texture. This is because the process is gentler to the food. And once freeze-dried food has been reconstituted, it comes back to almost 100 percent of its original quality and texture.
As long as you reconstitute it slowly, anyway. You have to be patient, or you get a normal exterior with a crunchy interior. It’s a jarring texture change, to say the least.
Difference #3: Storage Capability and Location
Freezers and freeze dryers use different processes to preserve food. Thus, you have to treat them differently when you store them. So, we’ll take a closer look at the differences between storing freeze-dried and frozen food below.
When it comes to storing food in the freezer, each food has a different shelf life.
Meats, such as bacon, will only last for a month in the freezer while some vegetables can last up to a year. Because these dates vary so much, you need to clearly label and monitor the food in your freezer.
Also, you must use the right containers to store frozen food because if you don’t, potentially the food will spoil. For freezing, you should use Ziplock or silicone bags, Pyrex bowls (read more about using Pyrex bowls safely in the freezer here), or a suitable wrapping parchment.
Some freeze-dried food can be stored for more than 20 years. But to make sure it lasts; you must store it away from moisture and oxygen. The best way to store freeze-dried food is in Mylar bags along with their oxygen absorbers. You can also store it in vacuum bags, cans, and jars, but some of these may shorten the shelf life of the food as they let in more air or light than Mylar bags do.
With freeze-drying, the shelf life of food is much longer than freezing. It’s still a good idea to label the Mylar bags (or other containers) with the date you sealed them, but with most freeze-dried foods, you’ve got as many as 25-plus years to eat them.
So, with freeze-dried goods, you don’t have to do regular food inventories to see which food is past its date.
Difference #4: Usage of Stored Foods
When you want to use frozen food, most of the time you’ll have to defrost it first. And you can do this by leaving the food in a refrigerator, submerging it in cold water, or by using a microwave.
Never leave frozen food out on the side to defrost because this will encourage bacterial growth and it can make your food unsafe.
When you want to use freeze-dried food it’s simply a case of adding water to bring it back to its original state. This is known as reconstitution.
However, each food is different when it comes to reconstituting. Some foods reform better when you rehydrate them slowly. While others, you can simply submerge in water until they’re back to normal.
Difference #5: Convenience of Stored Foods
Freeze-dried food is one of the most convenient foods around. It’s lightweight, so it’s easy to take with you camping, hiking, or on a road trip. It’s also much quicker to reconstitute freeze-dried food than it is to defrost frozen food.
With frozen food, a lot of the time you have to defrost the food for several hours before you use it. Whereas some freeze-dried foods can be eaten straight from the pack, without the need for reconstitution.
Difference #6: Cost of Appliances
Freezers have a bit of a leg-up on this area because most everyone already has a freezer. And if your freezer is too full? It’s a whole lot cheaper in the short run to buy another freezer. After all, you can get a quality freezer starting at only several hundred dollars (but the nicer ones cost more, of course!).
Buying a freeze dryer might seem like a big investment upfront, though, as they can cost anywhere from $2,000 to $5,000 or more, depending on your options (see how much a freeze dryer costs here).
However, it can save you money in the long run. Think about how expensive freeze-dried foods are in the store for example. As well as this, you can also save money by buying food in bulk and preserving them for future use.
Freeze dryers do consume power when you use them. But unlike a freezer, your freeze dryer won’t always be running. Overall, using a freeze dryer is a cost-effective way to build up a home food store.
Difference #7: Frequently Asked Questions
Freezers and freeze-dryers are both amazing devices. They each have a purpose, a time to use them, and other amazing qualities. But let’s make sure all of your questions comparing and contrasting the two get answered.
Don’t see your question? Contact me and ask – and I’ll get it answered.
When to Store Food in a Freezer vs Using a Freeze Dryer
Almost all food can be freeze-dried, however, sugary, and fatty foods don’t freeze-dry well. At the same time, foods such as pasta aren’t great in the freezer. So, there are certain times when it’s better to use a freezer over a freeze drier and vice versa.
Store These in a Freezer
- Bread – Although you can freeze dry bread, often, it won’t come back to the same soft, fluffy state. So it’s better to store bread in the freezer if you want to use it to make sandwiches.
- Sugary and Fatty Foods – Fat and sugar don’t freeze-dry well so it’s better to freeze fatty foods such as butter and chocolate.
Use a Freeze Dryer For These
- Fruits and vegetables – This is particularly true when it comes to ones with a high water content such as apples, pears, and cucumbers.
- Herbs and Spices – These preserve better in the freeze dryer, especially if you grind them up first.
- Cream or Milk-Based Sauces – Things such as custard tend to separate or curdle in the freezer. So it’s better to freeze-dry these. For rich cream or creamy sauces, you should water them down before you freeze-dry them for the best results.
- Eggs – Even though you can freeze eggs, you can only freeze them raw. But with freeze-drying, you can preserve both raw and cooked eggs.
- Cooked Pasta and Rice – You can’t freeze cooked pasta or rice, but you can freeze-dry them pretty well.
Can You Freeze Dry Foods in a Regular Freezer?
According to some websites, you can freeze dry food in a regular freezer. And technically, foods can be both frozen and dried in a freezer. However, the results will be nothing like the ones from a freeze drier.
When you use a regular freezer to freeze dry food, you have to leave the food unwrapped and directly exposed to the frost to freeze the food. Then, over time, the food will naturally dry out due to the cold, dry air.
Basically, you’re getting severely freezer-burned foods. This will severely damage (if not destroy) both the texture and flavor of the food.
And in most cases, you’ll end up with food that’s not very appetizing. As well as this, “freeze-drying” in a regular freezer can take several months.
Freezer vs Freeze Dryer – Pros and Cons
Both freezing and freeze-drying are good methods of food preservation and each has its own benefits. Overall, freeze dryers will preserve foods for much longer than a freezer. But they’re not good for preserving fatty foods such as butter.
So to summarize, let’s take a closer look at the pros and cons of freezing and freeze-drying below.
Freeze Drying
Pros
- Freeze dryers are versatile. You can use them to freeze-dry most food items, including whole, pre-cooked meals.
- Freeze-dried food retains most of its original texture, flavor, and quality.
- After freeze-drying, food is lightweight so it’s easy to transport and carry around.
- Freeze-dried food generally has the longest shelf life of all preserved foods, which can be more than 20 years in some cases.
Cons
- The biggest downside to freeze-dryers is their cost. Freeze dries are pretty expensive to buy.
- Freeze dryers don’t work well for fatty or sugary foods such as butter and chocolate.
- Freeze dries can be noisy.
Freezing
Pros
- Almost every home has a freezer. So freezing is a very accessible and convenient way to preserve your food.
- Using a freezer is quick and simple.
Cons
- Freezers can dramatically alter the texture and flavor of food and sometimes defrosted food is mushy.
- If food isn’t covered correctly in the freezer, it can get freezer burn. And this can spoil the taste and texture of your food.
- A freezer needs to be constantly plugged into a power source. If you lose power, your food will spoil.
- Often, you have to wait for food to defrost before you can use it.
Best Freezing and Freeze-Dryer Products
Want to do some shopping? Here are some of the best and coolest products.
- Tired of buying disposable Ziploc bags? Try these reusable, closable silicone bags instead.
- Need more mylar bags and oxygen absorbers? Grab this large, 5-gallon mylar bag kit set on Amazon – click there for the current sale price.
- Get more pint-sized mylar bags here on Amazon.
- Go disposable-free with this 24-count glass bento container kit on Amazon.
Conclusion: Freezers and Freeze-Dryers
Although buying a freeze dryer is a big investment, overall, it’s a better way to preserve most foods. Freeze-dried foods can last for years (up to 25 years or more) while frozen food can only last for up to a year.
However, freezing is always a better option for fatty and sugary foods. So, for the ultimate in food preservation, you should have both a freezer and a freeze dryer on your homestead.
Now that you know the difference between when to use each device, think about investing in a Harvest Right freezer (click here to see current sales). They’re the only brand we use and recommend.
Need to do more reading first? Gotcha covered. Go read this freeze-drying article next.
Resources
Learning from your own experience is essential, but learning from others is also intelligent. These are the sources used in this article and our research to be more informed as homesteaders.
- “79 Foods You Can Freeze Dry and 17 You Cannot: Complete Guide.” Backyard Homestead HQ, backyardhomesteadhq.com/77-foods-you-can-freeze-dry-and-17-you-cannot-complete-guide. Accessed 7 Oct. 2021.
- FDA. “REFRIGERATOR & FREEZER STORAGE CHART.” FDA, 2018, www.fda.gov/media/74435/download.
- “Freeze Drying – A New Option for Home Food Preservation • AnswerLine • Iowa State University Extension and Outreach.” Iowa State University Extension, 27 July 2021, blogs.extension.iastate.edu/answerline/2021/07/27/freeze-drying-a-new-option-for-home-food-preservation.
- Harvest Right. “How to Store Freeze Dried Food.” Harvest Rightâ„¢ | Home Freeze Dryers | Freeze Dried Food Storage, 15 Nov. 2019, harvestright.com/blog/2017/how-to-store-freeze-dried-food.
- “National Center for Home Food Preservation | How Do I? Freeze.” National Center for Home Food Preservation, nchfp.uga.edu/how/freeze/dont_freeze_foods.html. Accessed 7 Oct. 2021.
- Rey, L., et al. “Freezing and Freeze-Drying [and Discussion].” Proceedings of the Royal Society of London. Series B, Biological Sciences, vol. 191, no. 1102, The Royal Society, 1975, pp. 9–19, http://www.jstor.org/stable/76904.
- Starr, Kimberly. “How Do Home Freeze Dryers Work? Science and Process Made Easy.” Backyard Homestead HQ, backyardhomesteadhq.com/how-do-home-freeze-dryers-work-science-and-process-made-easy. Accessed 7 Oct. 2021.
- “The Science of Freezing Foods.” UMN Extension, extension.umn.edu/preserving-and-preparing/science-freezing-foods. Accessed 7 Oct. 2021.
- Utah State University. “Buying a Home Freeze-Dryer: What to Know Before You Go.” USU, 26 May 2021, extension.usu.edu/preserve-the-harvest/research/buying-a-home-freeze-dryer-what-to-know-before-you-go.
