How Does Freeze Drying Work?

Freeze drying is a remarkable method of food preservation that dramatically extends the shelf life of your favorite foods in a highly nutritious, light weight form that is easy to use in many ways. With a few exceptions, the freeze drying process will process almost any food in your kitchen, garden or pantry into nutritious, flavorful shelf stable dried foods.

What is the purpose of freeze-drying?

The purpose of freeze drying, in general, is to remove moisture from foods, pharmaceuticals, and other materials while preserving their quality and extending their shelf life. The Freeze-drying process, also known as lyophilization, involves removing moisture from a product through sublimation while preserving its texture, flavor, and nutritional content.

What is Freeze-Drying? The complete freeze drying process consists of three main stages: freezing, primary drying( my freeze dryer calls this stage vacuum freezing), and secondary drying.

Freezing: Once you place the food in the freeze-drying machine, it is frozen to a very low temperature, which solidifies the water content within it.
Primary Drying: Once frozen, the food dryer will create a vacuum. Under reduced pressure and controlled temperature, the ice within the product sublimates, transforming directly from a solid to a vapor. This phase removes the majority of the moisture.
Secondary Drying: After primary drying, the food is further dried at slightly higher temperatures to remove any remaining moisture.

Freeze Dried Fruits — Freeze dried fruits look almost like fresh

Importance of Food Preservation:

All methods of food preservation at home have something to offer your family. However, freeze drying food at home is especially good at maximizing the benefits of your investment.

Why Freeze Dry at Home?

The advantages of freeze drying include the superior preservation of flavor, texture, and nutritional value over other food preservation methods. This is especially true for the home preserver. Freeze drying also offers an extended shelf life at room temperature when properly dried and stored. If you’re looking for a way to store garden produce, meats, dairy products and much more, this is a fantastic solution.

Here’s a few points on why food preservation is something we should focus on, and why freeze drying at home makes sense.

Reduction of Food Waste: America has a food waste problem. We throw WAY too much valuable food away for various reasons. Food preservation methods like freeze drying, canning, dehydrating and regular freezing all help reduce food waste by offering good methods of easily preserving leftover foods, garden produce and more in the kitchen.

This is especially true with freeze drying. Freeze drying open up new possibilities for getting the most out of the food you cook at home. With little trouble you can freeze dry food otherwise wasted. This is especially true of leftovers. Rather than throwing away leftover food crowding the fridge, spread it on your freeze dryer trays and freeze dry it. Freeze drying casseroles, soups, stews and even cooked steaks, pulled pork and other meats will preserve it up to 25 years. And the taste is perfect with almost all its nutrients intact. Even the texture of your food is mostly retained with freeze drying.

Reduce Environmental Impact: Commericial large scale Food production and distribution have a significant environmental impact. By preserving and storing food at home, you can help reduce the carbon footprint associated with long-distance shipping and packaging. Plus you know what you are eating. 🙂

Cost Savings: Home freeze drying and other methods of food preservation can lead to cost savings in the long run if it fits your lifestyle. Reduce your food investment dollars whenever you can. Grow your own garden. If you can’t garden, try joining a local CSA or a local food gleaning club. Gleaning from harvested fields, harvesting otherwise unused tree fruits, grapes and other neglected crops from friends and neighbors will help reduce food waste and protect your hard earned dollars. Be sure to buy organic local foods in bulk or when they are on sale and preserve them in your freeze dryer. Use up leftovers by freeze drying them too.

Convenience: Having a stock of preserved foods on hand provides convenience and flexibility in meal planning. Freeze-dried ingredients can be used to create quick, nutritious meals, spice blends and snacks which is handy, nutritious and time saving. Until you actually get into freeze drying it’s not possible to really appreciate the potential of this.

Harvest Right Freeze Dryer Is A Good Tool For The Freeze Drying Process — My Harvest Right Pro Freeze Dryer

Is Freeze Drying Only For Foods?

Freeze drying foods and other products commercially has been done for decades. Commercial Freeze drying is not limited to food. It is also used in other applications like pharmaceuticals, biological research, and various other industries to preserve delicate materials.

How Did Home Freeze Drying Start?

The home food preserver had few options for attaining the freeze-drying process of food preservation until around 2016 when Harvest Right company designed and produced freeze drying equipment specifically to serve the home.

Today, There are several freeze dry machines designed for the home that can accomplish this process for the home cook. Harvest Right brand has been around the longest and has recently upgraded its machines and customer service. Blue Alpine Freeze dryers are new on the market and show a LOT of promise. But they are currently hard to source. Stay Fresh company also has a competitve freeze dryer. Check them all out and choose the one that best fits your lifestyle and pocket book.

Freeze dryers are pricey, but cost effective if you use them enough over a period of time. Considering the price of commercially freeze dried food, making your own freeze dried foods can pay back rather quickly.

If you’re considering getting into home freeze drying, it’s a good idea to research different models of home freeze drying machines. Read user reviews to find the one that best fits your needs and budget.

I purchased the medium sized Harvest Right Pro Fre eze Dryer and immediately put it to work.

Benefits of Freeze Drying:

Freeze drying stands apart from home canning, regular freezing, and regular food dehydration. Your home Freeze-drying equipment will preserve a large range of foods, and once packaged, requires no electricity to store.

AND this process will allow you to preserve most all of your kitchen foods, both cooked and raw. It easily protects the nutrients and useability of food. Freeze dried food is stored on the shelf at room temperature in a lightweight dry form in mylar bags, #10 tins, or sealed mason jars.

Emergency Preparedness and Food Security: Storing preserved food that requires no electricity to keep it useable and shelf safe is great for emergency preparedness. In the event of natural disasters, power outages, or other emergencies, having a supply of preserved food as meals ready to eat ensures your family is nourished in extreme circumstances, even when your normal food access is gone or severaly reduced.

Hiking, camping, biking, boating and other outdoor pursuits are so much easier when your food is lightweight to carry and easily eaten from a bag with just a bit of water to reconstitute it. Your freeze dried meals won’t as easily attract wild animals and the waste is minimal and simple to pack out. If you need to cook freeze dried meals on the trail nowasdays, small campstoves make it simple. All you need it water.

Health and Nutrition: This is a BIG PLUS. Freeze drying is a spectacular method of preserving the nutritional value of food. Unlike canning or traditional food drying, freeze drying retains 97% of the vitamins, minerals and trace elements of food. It also retains the natural flavor and color of the food.

Freeze dry herbs and other commonly used recipe condiments and add-ins like tomato sauce. Freeze dry bean dips, salsas or guacamole.

Whole Meals: Freeze dry and Rehydrate whole soups, stews, skillet meals and even casseroles when you want a quick meal.

Dog Food: Dog food can be made at home and freeze dried. You need to be careful here. Since dogs are not humans they eat differently than we do and need different nutrients. Be sure to work with your vet when planning to feed your dog food a complete diet made from scratch at home. Once you have it figured out, you can freeze dry your dogs food, just like human food. Package it for long term storage. Dog treats are also easy to make and freeze dry.

Culinary Creativity: You can experiment with recipes, flavors, and combinations using your freeze dried ingredients. The options here are endless. For example, its popular among freeze dryers with gardens to make tomato puree, freeze dry it and use it as a powder for LOTS of recipes from Pizza sauce to soup base.

Freeze drying offers you a different style of cooking. And a different, healthier option for making treats for the family, with fresh fruits leading the way. But even desserts like cheesecake bites and ice cream dollops are well loved freeze dried treats.

What are the Problems with Freeze Drying?

While freeze drying is an excellent method for preserving food and other materials, it’s not without its challenges and potential problems. It does require a mental and financial commitment.

Cost of Equipment: This is the biggest challenge for most of us. Home freeze dryers are expensive to purchase. This initial investment can be a significant barrier for individuals, but a small capital investment for small home businesses. For example, You can use your machine to make and sell freeze dried products to help pay the purchase price back. Many people sell freeze dried candy for this reason.

At this time, new freeze dryer manufacturing companies are coming into the market place which may significantly improve innovation and price competiveness of these machines in the near future.

Dedicated Space For Equipment: The freeze dryer and the motor for it will need a space off the floor (small sturdy table or bench) with a dedicated power outlet. These machines are heavy so they need a permanent home where it can work at between 45 and 90 degrees F for ideal performance.

Time-Consuming: Freeze drying is a time-consuming process, but actually require the same or less work from you the food producer as regular food drying. But you do have to realize it can take many hours, or even days, to complete the various phases of freezing, primary drying, and secondary drying, depending upon the product you are freeze drying. The dry time can be adjusted to suit your timeline though so don’t worry about this too much unless you intend to go into high production year round. Then you may need more than one, or a larger machine.

Energy Consumption: Freeze dryers can consume a significant amount of energy, especially during the freezing and drying phases. This can result in higher utility costs. This is important to add to the cost of your freeze dried foods. You may want to build your budget on high value foods that pay back well.

Maintenance: The Freeze drying machine and pump requires regular maintenance to ensure it operates efficiently. This includes cleaning, calibrating, filtering and changing the oil in the pump, and replacing parts as needed. And your machine life depends on you doing this. Don’t neglect your freeze dryer maintenance.

Food Texture: While freeze drying preserves the nutritional value and flavor of food exceptionally well, it will change the original texture. Most freeze dried foods have a crunchy or powdery texture before rehydrating. But most often the food will rehydrate with the same or better flavor than the food started with and the texture is most often very similar to fresh after rehydrating.

Storage Space: Freeze-dried food takes up less space compared to fresh food, but it still requires storage space. Consider your available storage space for dried foods when planning to freeze dry food.

Freeze Dried Meats — Freeze dried meats reconstitute really well.

Summary:

Freeze drying is a significant investment. but it may be worth it if you have the lifestyle and are interested in food preservation by this method long term.

Despite it’s challenges, freeze drying is a valuable food preservation method that can pay back large dividends. You can freeze dry a wide range of delicious foods that you can’t with other methods.

This is particularly attractive to home preservers when the high-quality preservation, high nutrient retention and long shelf life are considered.

I’m planning a full section on this Homemade Food Junkie blog all about freeze drying. I’ll include freeze drying methods, meal prep and recipes that use freeze dried foods. Ask your questions about this topic in the comment section below. I’m looking for topics home cooks want answers for. Let me know what you want to know about home freeze drying and I’ll do my best to find you answers.
Have a wonderful day!
Diane