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How To Freeze Dry Food At Home

Can you visualize if you are prepared for an emergency with a food supply that would last over 30 years without spoiling? Let me rephrase this, do you want to know or learn how to freeze dry food in the convenience of your home. Well, folks, I like to brainstorm and share new ideas and inventions, which in due course could help someone in some way.

>>Read our post on Best Vacuum Chamber For Freeze Drying Food<<

Nevertheless, here is the thing the reason you should know about this particular subject at hand is that we live in a crazy world and it is a happening place. A personal supply of frozen dry food could help you and your families survive disasters and any other emergency.

Last but not the least, can you envision if this form of food storage was actually smaller and lighter than regular food, and can be prepared very cheaply with minimal time investment. Well, good news folks! This technology at present exists. It is known as freeze-drying (or lyophilisation or cryo desiccation or “suspended animation” for food ).

A Little Bit of History

Freeze-drying was first invented during World War II to solve the problem of food being spoiled while shipped for wounded troops.

What You Will Need to Follow This Tutorial

You will need the following equipment (appliances) for the freeze drying process.

1. Freeze Drying with a vacuum chamber

The quickest and most efficient means of freeze drying is with a vacuum chamber. However, there is an alternative method available which is freeze drying with a freezer.

A. Freeze drying with a freezer

When and if a vacuum chamber isn’t easily assessable to you, however, you can still follow this tutorial and freeze dry your food. The only thing you need is extra time. This process works by chopping food into small pieces and place them on a perforated tray in the freezer (This method works much better in non-frost freezers). Once the food is frozen in the initial few hours extending on to the next week the process of sublimation should take over (all the moisture will be removed). Moreover, to ensure the process is working test the food by letting a piece thaw outside. If it turns black rapidly, it isn’t set yet. If the food color doesn’t change, move on to the next step of storage.

2. Freeze drying with dry ice

There's another alternative way to freeze dry food, and that's by the utilization of dry ice if the choice of above two mentioned methods is not available. In a small humid setting, water molecules are strained out of a material such as food. The food you need freeze-dried has to be surrounded with dry ice (CO2 in its stable solid state), this will create a near-zero humid setting, will drain the moisture extremely efficiently. You'll need a box double in size to the amount of food you're going to freeze dry (Tupperware would be a good choice). Then makes some pits on the lid for the various gasses to escape. Add equal amounts of dry ice and the food you'd like to freeze dry into the box. Alternating with one layer of dry ice, with a layer of food, etc. goes well together. Soon after this place the box in the freezer, to solidify the dry ice further for as long as you can. Inspect after every 24 hours till the dry ice vanishes. The food should now be fully frozen dried, and all set for storage.

3. Freeze drying with Freeze Dryer

The fourth alternative Freeze Dryer is an expensive option that carries a considerable price tag, so I recognize it’s not one of the regular appliances like a microwave, or something you buy just “for fun”. Freeze drying technology previously something only big companies could afford in commercially packaged goods. However, before an analogous freeze dryer before Harvest Right used to cost over 30 grand and it had the capacity to process about the same amount of food in a single batch as this one. Moreover, the team behind Harvest Right spent many years improvising a way to cut the price tag to about 1/10 of the price, that can be plugged into a regular home electric outlet, and easily used at home. Although it still an expensive equipment at $3-4K, however, the freeze dryer has the capacity to dry about $10 grand worth of freeze dried food in a year. Several studies have shown the average American family trashes out around $2,5 – $3 grand worth of food every year, so all of that helps put things into perspective a little bit!

     Storing freeze dried food

      What can be freeze dried?

Step by Step Instructions

Freeze Drying With a Vacuum Chamber

This is the most efficient and swift method to freeze dry food (a).

1. First the food is frozen.

You should first get the food ready on your kitchen table or countertops so that it is easier for you to make sense of what food needs to be freeze-dried.Get that one right.Once you are done with that step, then place that food in the freezer for some time till it is completely frozen solid. Make sure that you do not put a lot of food for freeze-drying in one go since the freezing process won’t work efficiently and it can even harm the freezer,so that is one the first precautions. The food should be put in the freezer in small loads to ensure the food gets frozen completely.Figure (a) displays the vacuum chamber method for freeze drying food and vegetables.It is a very handy and efficient method and has been used for many years and is quite popular with the general public and it has proven impact on the freeze-dried food industry.

2. The vacuum chamber

The food is then put in the vacuum chamber at a pump level below 133 x 10-3

Once in the vacuum chamber all the remaining air is sucked out of the frozen food and it is then ready for storage.

If you carefully follow the step-by-step instructions which are also shown in figure (b), the vacuum atmosphere will cause sublimation to occur in an expedited manner, and more food can be freeze dried in less time.

Once completely sublimated, the food is prepped for storage. Virtually all and any edible food item and food ingredient can be freeze-dried.

However, when deciding which options to use it is important that you choose a freeze drying method that is efficient, fast, and appropriate and gets you the best results.

Since some options mentioned earlier requires specialized equipment. There have been rumors about free-dried food low on nutrients.

However, that is not the case. If you read literature on freeze-dried food, you will learn that most of the nutrients are preserved in the food and in most instances the the food retains its texture ,taste and freshness when ready to consume.

Figure (b) displays the vacuum chamber that is mostly used at a commercial level to freeze-dry food. However, the smaller consumer version of the vacuum chamber performs the same task on a smaller scale.

For those that don't have vacuum chamber, check this out.

For 3 gallon or less jobs, the ProVac vacuum chamber gets the it done.

3. Additionally, some backpackers and travelers freeze-dry their own food.

However, they have preferences for types of food that are already freeze-dried such as Mountain House brand (figure c).Figure (c) below displays a tub of Mountain House freeze-dried food brand.If you have observed lately, with the migrant crisis recently in Europe, relief and rescue workers have been handing out freeze-dried food tubs to refugees.

The branded free-dried food is an easier option for relief organizations since the food remains unspoiled and a tub of a freeze-dried meal can feed a whole family depending on the number of household members.

4. Preservation of Cellular components

Moreover, the cell structure, its nutrients, consistency, and color are all preserved due to the rapid change, which allows the food to retain its looks and texture. It is worth noting that all the fresh foods have water, which is known to be their primary source of weight. Moreover, fruits are made up of greater than 80%-90% water by weight.

During the dehydration process about 98% of the moistness from the food is removed, that ultimately results in reducing the weight of the food as much as 90%, thus making it lightweight for the purpose of backpacking as well.

Moreover, apart from backpacking and camping, the freeze-drying process is also regularly used by the military to make freeze-dried foods easier for one person to carry large amounts of food.

Figure (c) below displays a tub of Mountain House freeze-dried food brand.If you have observed lately, with the migrant crisis recently in Europe, relief and rescue workers have been handing out freeze-dried food tubs to refugees.The branded free-dried food is an easier option for relief organizations since the food remains unspoiled and a tub of a freeze-dried meal can feed a whole family depending on the number of household members.

Here's a video on how to freeze dry food at home.

Storing Freeze Dried Food

Once you are done freeze-drying, for whatever reason you have chosen either with a vacuum chamber or not, set the food in airtight, moisture-proof bags. Moreover, you can use a vacuum packing machine if it is readily available to you.

However, Ziploc bags work fine too, as long as a vacuum can be created in them. Now you can seal them up and put them away in your preferred storage space.

Finally, you now have freeze-dried food ready, along with other emergency food supply that will be good for decades to come! I want to put a lot of emphasis on the fact that this technology has been doing wonders with the current refugee crisis. European nations have vast storages of freeze-dried food not just for its own population but also for the neighboring countries.The reason behind this is that in Europe a lot of wealthy nations are surrounded by weak and poor European counterparts.Therefore, in the light of anticipated crisis the rich European countries prep themselves for upcoming disasters of food shortages. Moreover, the USA. also has vast storage of freeze-dried food to cater to its own disaster relief efforts as being a continent in itself the USA has no shortage of crisis and disasters happening on its land.

What Types of Food to Freeze Dry?

There is a diverse variety of food available in the grocery stores that you can freeze-dry such as certain vegetables and tops my list. Apples and potatoes are good starters since they are the easiest. Some people even freeze-dried ice cream. Nevertheless, a word of caution here though, from previous studies it is known that water is the only known substance that sublimates, therefore,  you may want to eliminate all the water moistness.

Some brand of alcohols and a variety of acids can still have an impact on the storage and chemical stability of your food. Occasionally test your freeze dried food to make sure it has transformed efficiently and will come in handy for you should the day come when you actually need it.

Conclusion

As I mentioned earlier of all the fantastic, exciting, and innovative appliances I’ve worked with, the food vacuum chamber was downright the most incredible. It's, however, the first machine of its kind for in-home use.

Moreover, I am making a real effort here not to sound like an infomercial when I am giving out this information about this particular piece of equipment. I enjoy sharing cool things with you awesome people and shedding light to kitchen products that you might not know exist and can come in handy someday. Even if at this present time it’s not in your budget, or you’re not interested in purchasing one, I hope that you will enjoy reading this tutorial. Moreover, if you like this tutorial, I would really appreciate that you l leave a positive comment in the comment box!

DISCLAIMER: the tips provided in this list does not guarantee survival. We are providing insights based on our own knowledge and experience. We simply sharing our personal ideas and opinions with our audience. Use the outlined advice at your own risk.

Additional resources: 

  • ​When considering different frozen foods to eat, make sure you have a weight scale on hand to keep your body fat percentage in check. 

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