The Method of Freeze-Drying
Freeze-drying is a complex method of preserving new or currently-cooked foods by taking away up to 98% of the food’s dampness, leaving intact the food’s texture, taste, aroma and dietary value.
The method needs that the fresh or cooked foods be speedily frozen at temperatures as low as -50°C. The frozen meals is then put into a vacuum chamber. This vacuum chamber lowers the pressure, and raises the temperature to just about 0°C.
At this particular temperature and pressure, the ice crystals in the meals evaporate into water vapor, bypassing water’s liquid type, by means of a method referred to as sublimation.
This approach preserves the mobile composition and dietary content of the foods, ensuing in a merchandise that, when rehydrated, quite intently resembles the authentic food.
The method also prevents the h2o from getting reabsorbed by the food and thus decreases its fat considerably.
Most foodstuff items such as fruits, veggies and meats are well-suited to freeze-drying, and can be employed for extended-phrase food storage and preservation.
The Approach of Dehydration
Dehydrating foodstuff is a food preservation strategy which has been utilised for hundreds of years. Native Americans dehydrated their buffalo kills in their looking camps to make it simpler to transportation. Pemmican (a dehydrated concoction of buffalo meat blended with unwanted fat and berries) was a staple of many of the nomadic North American tribes. This lower-warmth dehydration process included either air drying (with nearby campfires), or sunshine drying strips of meat on drying racks.
Dehydrators are a modern technique for gradually removing the humidity from meals with no really cooking it. A drawback of dehydration is the minimal volume of foodstuff which can be dried at one time. The optimistic element of dehydration is that this method of processing for foods storage can be easily completed at house.
How Do These Two Approaches Have an effect on the Meals?
Freeze-dried foods maintain much of the authentic shade, condition, aroma and freshness of fruits, vegetables and meats. Freeze-dried meals does not usually incorporate additives or preservatives, so it remains correct to its authentic sort. And the look, texture and flavor of the foods stays following re-hydration.
Unlike low-heat dehydration, freeze-drying enables for the preservation of pre-cooked foods, including recipes this sort of as soups, stews, stroganoff, and the like. An evident gain is that since the food was ready in its entirety prior to freeze-drying, all you need to do is simply include h2o, then warmth for a couple of minutes in buy to generate sumptuous foods.
Rehydrating freeze-dried foods will take just a few minutes, basically by introducing boiling water. Some foodstuff, like numerous fruits and vegetables, want no re-hydration just before consuming.
Dehydrated meals shrink throughout processing as the moisture is removed. So the food product itself is substantially smaller sized than its unique size.
The re-hydration time of dehydrated foodstuff requires a little bit more time than freeze-dried, but it stills preferences like the original form of the foods. Some dehydrated foods have added substances to improve flavors or aid in preservation. As with freeze-dried fruits and veggies, dehydrated fruits and veggies can be eaten with out any re-hydration.
Both techniques of food preservation boost the long-phrase storage lifestyle of foods. Most commercially produced freeze-dried and dehydrated food items have a shelf daily life of fifteen to twenty several years, if properly packaged and stored in a cool, dry setting.
In addition to their currently being a reliable source of foods in an emergency or lengthy-time period survival scenario, since of their light-weight excess weight and ease of portability, these food items are also great for using on tenting, climbing and hunting journeys. They are also a clever selection to hold in an emergency street-facet kit for the auto, or in your bug out bag.
If you choose to preserve these foods in your automobile as part of an unexpected emergency kit, make sure you don’t forget to rotate them periodically. Daniel Zetterholm in a vehicle can reach extremes, equally hot and cold. High heat as nicely as steady temperature fluctuations contribute to a lot quicker degradation of both dehydrated and freeze-dried foodstuff.
Which Variety is Far better for Intake?
Everybody is diverse, and each particular person has their personal personal tastes and choices. With that in thoughts, there are a couple of factors to consider prior to making a choice in between freeze-dried or dehydrated foods.
House-grown fruits and greens are better preserved through dehydration, given that the regular particular person can’t manage the expensive equipment utilized in freeze-drying.
Foods utilised in every day cooking and meal preparing should almost certainly be freeze-dried. This permits the meals to be swiftly re-hydrated as it is cooked prior to serving. If accessibility and portability are important, than either variety of preserved foods should satisfy these particular needs. Once yet again, it is a subject of personal preferences.
In a nutshell, each dehydrated and freeze-dried foodstuff are excellent options for extended-term foods storage, as effectively as for daily use or for hiking, tenting, and so forth. They both provide gentle-weight, transportable, handy foods. The main variation is that freeze-dried foods are inclined to greater maintain the shape, texture and flavors of the original meals.
Most people will locate that a blend will perform ideal for their demands. Single-product foods such as vegetables, potatoes, and other staples and grains are effectively-suited to lower-heat dehydration. Freeze-drying is a lot more suitable for meats and fruits (whose texture can be preserved), and for pre-cooked foods with a assortment of elements these kinds of as soups, stews and sauces.