How Long Does Food That Has Been Freeze-Dried Stay Fresh?
If there is one thing that a global epidemic has taught us, it is that it is a smart option to have a few essential items in our pantries that we can use in case of an emergency. As the price of everyday necessities continues to skyrocket, more households are giving serious consideration to building up their emergency supplies in case of any unexpected circumstances. People are stockpiling basic necessities such as water and powdered milk, and some are even resorting to freeze-drying to have their supplies ready for the long haul. The trend of shopping in bulk has also increased.
Foods that have been freeze-dried typically have a storage life of between 8 自 20 年 (even 30 in some cases) depending upon the type of product that is freeze dried and the storage. The method is an effective approach of retaining the majority of a food’s nutritional value while also maintaining its structural integrity. When something is freeze-dried, about 98 percent of the moisture content is removed, which eliminates one of the major elements that are required for deterioration.
There are still a number of unanswered concerns, despite the fact that more and more households are becoming familiar with the freeze-drying method. Which foods benefit the most from being freeze-dried? What’s the difference between dehydrating something and freezing it to make it dry? How long does such an item have before it goes bad? You wouldn’t want to go through the trouble of freeze-drying strawberries only to find that they’ve lost all flavor by the time you need them. Why put in the effort to stock your cupboard with freeze-dried meals if they won’t endure or be of any use when you want to use them?
What exactly is “freeze-drying”?
In the process of freeze drying, an item is subjected to a combination of a vacuum and heat, which causes the water to shift directly from a solid state into a gaseous state without first turning into a liquid. This allows moisture to be extracted from the item.
Consider it this way: if you put a handful of frozen strawberries into a dish, some of them will become ice crystals, while the rest will melt and become more liquid. If, however, you were able to eliminate the moisture by subjecting the fruit to heat and pressure, bypassing the melting process, you should be left only with the purest form of the product, devoid of any trace of water content, the water having been converted into a gas.
When freeze-dried and adequately packed, the vast majority of items have a storage life of between 20 和 25 年.
How long has the process of freeze-drying been used?
The process of freeze drying was initially developed in France in the year 1906, but it wasn’t until World War II that it was refined and put to use for the purpose of transporting penicillin, blood serum, and other medical supplies that needed to be preserved. The discovery made by scientists was that by using this procedure, they could help assure that organics would not go bad before they arrived at the hospitals, where doctors and nurses were urgently fighting to rescue patients.
In the 1950s, businesses started using the freeze-drying method to lengthen the period that some commodities could be stored after being prepared. While the military put this technique to use to improve their MREs, NASA took the concept of freeze-drying and ran with it to ensure that its astronauts had access to the critical foods they needed while they were in space.
Coffee was the initial food item to be frozen, but now practically anything can be perfectly preserved using this approach, from whole meals to emergency supplements to desserts like ice cream.
Which Kinds of Foods Can Be Dehydrated Using the Freeze-Drying Method?
The majority of households preserve perishable goods, such as fruits, vegetables, dairy products, or meats, by the process of freeze-drying. Although certain foods lend themselves better to the freeze-drying process than others, it is important to be aware of which goods may be used and which should be avoided.
Foods that don’t suffer too much damage when frozen and dried.
The following is a list of foods that perform very well when subjected to the freeze-drying process.
Because most fruits, including strawberries, 蘋果, and even bananas, have a high percentage of water, this technique of preserving food is well suited for preserving foods that have high water content. The end product is a fruit piece that keeps its primary form and the nutrients it contains.
Potatoes, radishes, tomatoes, 芹菜, squash, and eggplant are just a few of the vegetables that are able to withstand the rigors of the freeze-drying process. Freeze-drying something may be a more efficient method of prolonging the lifespan of an item than canning it, which is what the vast majority of preppers do with their home-cooked veggies. Canning is only anticipated to last for a few years, thus, most long-term pantry users can only do it once a year to meet their most fundamental requirements. 相反, they save their freeze-dried provisions for longer-lasting and more severe food shortages.
Because of their high moisture content, meats like hog, poultry, and cattle are quite amenable to the freeze-drying process (raw or cooked). Raw freeze-dried meat may be kept in the store at room temperature for up to ten to fifteen years if it is first cooked and then vacuum-sealed in an airtight container. To prepare the meat for usage, you need to run it under water and pat it dry using a paper towel before seasoning it and cooking it on a barbecue grill in the same manner that you would any other piece of conventional meat.
After being subjected to the freeze-drying process, dairy products such as milk, egg, and cream produce a powder that may be used. After that, the powder may be kept, and when it is time to utilize it, it can be rehydrated with water.
Herbs & Spices
A lot of preppers choose to plant their own herbs and spices and then freeze-dry them so they may use them whenever they need them. It is also possible to freeze-dry sauces, which will result in the creation of powders. In the pantries of many people who believe in the value of long-term food preservation are packages of sauce or buttermilk, both of which are used in baking.
Prime possibilities for freeze-drying include liquids like coffee, milk, and juices, as they can be powdered after being freeze-dried.
Freeze-drying is not appropriate for any kind of food that has a foundation of oil. Some varieties of peanut butter, margarine, lard, jams, syrups, mayonnaise, and chocolate are examples of these products. These types of meals do not have a sufficient amount of moisture for a procedure that depends on drawing water from foods since it cannot operate with foods that have too much water in them.
The freeze-drying procedure does not work very well with foods that are high in sugar content. For instance, pineapple juice and fructose syrup are not good candidates for being freeze-dried because of their high water content.
Many different kinds of snacks, such as Oreos, cakes, pies, 餅乾, and Twizzlers, will not be significant enough for freeze-drying to be worthwhile.
What is the Distinction Between Freeze-Drying and Dehydration?
There are a lot of individuals who are under the impression that dehydrating and freeze-drying are the same thing, which is not so.
The Stages of the Dehydration Process
Dehydration removes moisture from foods by subjecting them to hot air, in contrast to drying, which relies on other methods. After that, the product is sealed so that no further moisture can make its way inside while it is being stored. Since ancient civilizations first recognized that by heating things in a stone building, they could prolong the life of meat for a longer period, this method has been in use for many thousands of years.
During this procedure, the object is first frozen, and then, as it is subjected to pressure and heat, the water content is nearly entirely (98%) eliminated while maintaining the item’s vital integrity.
As was indicated before, freeze drying proved to be an effective method for preserving medical supplies and delivering them to the exhausted soldiers who were fighting and dying on the front lines in Europe during World War II.
Later on, commercial applications grew prominent as NASA developed methods to use the technique to deliver meals for astronauts as they tried to journey into space. This led to the popularity of commercial applications.
Freeze-dried food can remain fresh for a long time when stored properly. The exact shelf life of freeze-dried food depends on various factors, such as the type of food, the packaging, and the storage conditions. 然而, as a general rule, freeze-dried food can last for several years when stored in a cool, dry place and in an airtight container. Proper storage helps preserve the quality and flavor of freeze-dried food and ensures that it remains safe to eat. It is important to follow the storage instructions provided by the manufacturer to ensure that your freeze-dried food stays fresh and retains its nutritional value.