Are you sick of constantly throwing away the food you shoved into the fridge to “use later”? Food waste is a major concern in the modern world, and tossing out spoiled produce every few weeks really starts to add up – both for the planet and your pocketbook. CNBC estimates that the average family of four annually wastes almost $2,500 in food costs because it goes bad before they get to it. Not only is that a massive waste of a household’s money, but it’s also a gross misuse of the world’s limited food supply.
The news isn’t all bleak. Technological advances are making it easier than ever to preserve food, which is why you need to look closer at the reasons why you need to invest in a home freeze dryer. These innovative devices let you store and preserve almost any food for decades without compromising its nutritional content. Freeze dryers might look expensive, but considering the food waste they help prevent, yours can pay for itself in a matter of years.
The Science Behind Freeze Drying
Lyophilization, more commonly known as freeze drying, is the scientific process of removing water from food by causing it to shift from a solid directly into a gas (skipping the liquid stage). In the natural world, this process is called sublimation, and it takes place when water molecules are exposed to both pressure and bitterly cold temperatures.
In the same way, freeze dryers work by first flash freezing food so that the water content forms ice crystals. It’s then put into a vacuum, which turns the crystals into a vapor. A low-temperature condenser plate then pulls the resulting gas from the chamber without damaging the structure of the food itself. This process usually takes between 24-48 hours, and the final result is a water-free, chemically-stable food product that can be eaten more than 25 years after you freeze it.
Once it’s time to eat, freeze dried food can be enjoyed precisely as is, or you can “cook” it by rehydrating it with water to restore the texture to resemble fresh food. Best of all, upwards of 97 percent of the food’s nutritional content remains intact for as long as you store the food.
Not sure whether you’ll like the taste? Consider buying pre-packaged freeze-dried food to see what your reaction is.
How Freeze Drying Got Started
Though the science involved still seems vaguely space-age, freeze drying has actually been practiced for thousands of years. The Peruvian Inca are the primary example, as they relied on the strong winds and chilly alpine conditions of the Andes to freeze dry their potato crops and keep them preserved for decades at a time.
Freeze drying didn’t move out from the natural world until 1905 when the first machine capable of it was invented. Its initial purpose was purely medical, as World War II doctors relied on freeze-dried medical products like organ tissue and blood plasma to supplement overseas soldiers.
In the decades that followed, freeze drying technology continued to develop, and researchers noted its potential for food preservation. Those experiments paid off, and today there are over 400 types of freeze-dried foods commercially available. These impressively preserved meals are meant to be taken on wilderness excursions, stockpiled in case of emergencies, and they are the central sustenance for astronauts in space. No matter your motive, there are plenty of benefits of making and using freeze-dried foods right at home.
10 Benefits of Home Freeze Drying
For those familiar with home preservation, it’s immediately apparent that freeze drying offers some profound benefits.
1. Little Equipment Necessary
Are you sick of finding canning supplies everywhere in the kitchen? Freeze drying requires nothing more than a mid-size machine, and it’s easy to store away when not in use.
2. More Natural Flavor
Unlike canning (which requires sweeteners or vinegar) or dehydrating (which can turn produce a little bland), freeze drying preserves far more of food’s natural flavor so that it almost tastes the same as fresh when you rehydrate it.
3. Natural-Looking Appearance
No one wants to deal with shriveled, dull-colored foods, so it’s a benefit that preserving produce through freeze drying helps it retain its bright hues. That makes it significantly more appealing to put on a plate.
4. Almost Full Nutrition Content
Because flash freezing preserves food at peak freshness, it’s a perfect strategy for retaining up to 97% of foods nutritional content when fresh. In contrast, other preservation methods rely on heat which can destroy more than half the nutrients in food. Others owe their shelf-stable properties to potentially toxic preservatives like high fructose corn syrup, trans fats, or sodium nitrate.
5. Less Food Waste
If you’re sick of tossing out leftovers every day, freeze drying is a smart solution to preserve them practically indefinitely.
6. Decades, Not Years, of Shelf Life
Food stays fresh in your freezer for about six months, and you might get three years from your canning shelf. But a freeze dryer? That can provide you with over 25 years of preservation potential, meaning you might be eating yesterday’s garden harvest sometime in the next decade.
7. Cost Effective
Home freeze dryers are coming down in price every year (you can snag a Harvest Right for under $2,000!) With regular use, your purchase will start to pay for itself.
8. Straightforward Preparation
There’s no slicing, dicing, or other prep required before using a freeze dryer. Just pop your preferred food on a tray, turn it on, and let it get to work. You won’t even have to set a timer, as most machines are designed to turn off when they’re done automatically.
9. Lightweight Storage
Because the bulk of food weight comes from its water content, flash freezing food pulls out most of its weight and leaves you with a light, versatile food item that is convenient for travel.
10. More Efficient Pantry Storage
Home canners know how quickly all those jars can take up valuable pantry space, but freeze-dried foods take up little space and are easy to store, especially when they are vacuum sealed.
How to Use a Freeze Dryer at Home
Once you have the right equipment, home freeze drying is a straightforward process. Most machines offer space for you to preserve several trays at once, so fill them with prepped food (ensuring individual pieces aren’t touching each other). Since a freeze drying cycle takes up to two days, it’s smart to fill each machine as full as you can before starting it. For best texture, consider blanching vegetables beforehand and making soups thicker than what’s called for (you can add extra water when you rehydrate things).
Once everything is in place, you can start the action. Your freeze dryer will begin to seal itself and drop the interior chamber temperature until the food inside is frozen solid. From there, the vacuum pump will remove air from the chamber and phase the resulting ice crystals directly into a vapor that is released from the dryer. The water removal process typically takes hours, but freeze dryers like the Harvest Right self-monitor during the process and turn themselves off once the process is completed.
The Best Foods for Freeze Drying
While just about any food type can be freeze-dried successfully, some produce better results than others. Foods that are most suitable for long-term storage include:
- Fresh fruits, vegetables, and herbs
- Dairy products
- Meat (cooked or raw)
- Whole meals (casseroles and pasta dishes work especially well)
- Loaves of bread
- Liquids like soup, yogurt, and even coffee*
*Note: Instant coffee is the most popular freeze dried food of all time and partly responsible for making the technology mainstream.
As a general rule, anything with a high fat content is not suitable for freeze drying. This is because fat can melt during the lyophilization process, potentially coating the inside of your machine. Watery fruits and vegetables like lettuce or watermelon also don’t work well because they completely lose their structure when the water is removed. Finally, foods that use sugar as a preservative (like jam) tend to have their texture destroyed when freeze dried.
Storing Freeze Dried Food
When the freeze drying process is completed, you’ll be left with impossibly light, wafer-like foods that can be eaten as-is if desired. To maximize their potential for long-term storage, you’ll need to store it in moisture-free packaging. Vacuum-sealed mylar bags are a smart option, as are canning jars (so long as they are kept away from direct sunlight). The primary concern is to keep the food from interacting with water or oxygen, as both compounds will cause it to spoil more quickly.
How to Rehydrate Freeze-Dried Food
Freeze drying might take close to 24 hours to complete, but you can restore your meals to edible quality with mere minutes of prep time. The best rehydration strategy is often to place the freeze-dried food in a bowl of hot water to allow it to draw water back in. Drain away the excess after about five minutes, and complete the heating process in the microwave. Bread and pasta dishes are best restored with a gently steaming so that they retain their shape, and delicate greens should be crushed into sauces or spritzed with water before serving.
Once you realize how easy making and using freeze-dried food can be, this innovative preservation technique might become part of your midweek meal prep. Experiment with a home freeze dryer today, and your household’s food waste might soon be reduced to nothing.