3 DIY freeze dryers you can make at home
If you’re curious about the freeze drying process but the high price of commercial freeze dryers puts you off, you might be pleased to know that you can build your own.
Although building your own DIY freeze dryer may seem daunting, once you understand how freeze drying works, you’ll find that it’s totally possible. If you want to know what it takes, here are three freeze dryers you can make at home.
Why build a home freeze dryer?
The biggest downside to freeze drying food is the incredibly high cost of commercial machines. That’s why building your own DIY freeze dryer might be well worth your time and effort.
With a little patience, you can avoid the high price of commercial freeze dryers, which start at $2,500 and go up to $6,000 depending on size. Luckily, there are a few project guides to help you build your own home freeze dryer. Soon you will be freeze drying all your favorite foods which, if stored properly, can last up to 25 years.
If you choose to build your own freeze dryer at home, you can expect to hold all kinds of foods for short and long term storage. From berries and fruits to meat and whole meal leftovers, freeze-drying is a process that doesn’t change the shape, size, or color of your canned foods.
You can use your DIY freeze dryer to prepare meals for the hike, store your extra garden produce, or preserve meats and vegetables you buy on sale at the supermarket. Whatever you plan to use your freeze dryer for, building your own freeze dryer can save you a lot of money.
1. Easy Home Freeze Dryer
You may have heard of astronaut ice cream; it is one of the most famous examples of freeze-dried foods. Developed for space travel, astronaut ice cream is real ice cream with all moisture removed through the freeze-drying process. You can buy this space treat from the Astronaut Foods website, but of course you can replicate it at home if you build your own freeze dryer.
The easy part of this project is choosing the materials. You can find everything you need to build this freeze dryer on websites such as Amazon or at a local hardware store. Some basic components include a few vacuum chambers, a regular cooking pot, dry ice, polystyrene, and denatured ethanol (aka methyl alcohol). You will need minimal tools to assemble these parts together. At some point you will need a spade bit and a drill to widen a hole, but otherwise most parts are secured with bolts and hose clamps which can be tightened with a wrench.
More importantly, you will need a vacuum pump and a digital gauge to ensure you can achieve a low enough pressure for sublimation to occur. In simple terms, this means that the frozen water inside the food turns into vapor, without passing through the liquid stage first. For an overview of the science as well as exactly how to build a freeze dryer yourself, this project video will have you covered.
2. Inexpensive DIY Freeze Dryer
Not sure if you want to tackle building a freeze dryer yourself? Then take a short break of five minutes to watch this video. It briefly covers the science behind freeze drying while giving you an overview of the parts and construction needed for this project. Most parts can be purchased online or at a hardware store; at the time of the video’s posting, they cost less than $200.
Again, you will need a vacuum pump that can reach extremely low pressures. You will also need foam insulation, dry ice, and strong glass bowls to create the steam trap, all connected by strong plastic pipes and metal fittings. Although the process involves the use of a drill press which you may not have easy access to, the cost is undoubtedly more affordable than a commercial freeze dryer.
3. Simple home freeze dryer
Finally, if you want to try freeze drying food without buying specialized equipment, there is a way. This project on Instructables was designed by someone who works in a lab with desiccators, aka those little packets of beads that are included in the packaging to keep products dry. By using desiccators to suck out the moisture and a freezer to lower the temperature, you can effectively freeze-dry your food – it just takes a little longer.
Instead of a vacuum pump, you simply need a wine saver hand pump to lower the pressure inside the container you want to use. Inside this container, place the desiccators on the bottom to absorb the moisture, with the food you wish to freeze-dry placed on top (a divider is placed between the two). To mimic the low temperatures required for the process to work, place the low-pressure container in the coldest part of your freezer. After a day, check if you need to replace the desiccant inside, then put the vacuum container back.
Freeze-drying takes about a week, which is much longer than a commercial machine: the latter can freeze-dry items in 24 hours. However, for this incredibly cheap and easy-to-do freeze-drying process, it’s definitely worth a try.
Build your own freeze dryer
If you’re a DIY enthusiast, building your own homemade freeze dryer is a great weekend project. Especially if you have experience with machines like vacuum pumps and press drills, building a freeze dryer is a much more affordable option than buying a commercial unit.
Even if you don’t normally work with special power tools, you can freeze dry food with nothing more than a wine-saver hand pump and the clever use of desiccants and a freezer. With the help of science and DIY design skills, building your own freeze dryer is totally doable.
Try these exciting DIY projects this year and save some extra cash.
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