The Process of Freeze-Drying
Freeze-drying is a intricate procedure of preserving new or presently-cooked foods by removing up to 98% of the food’s dampness, leaving intact the food’s texture, flavor, aroma and dietary benefit.
The method requires that the fresh or cooked food be rapidly frozen at temperatures as reduced as -50°C. The frozen meals is then positioned into a vacuum chamber. This vacuum chamber lowers the stress, and raises the temperature to just about 0°C.
At this particular temperature and stress, the ice crystals in the foods evaporate into drinking water vapor, bypassing water’s liquid type, via a procedure referred to as sublimation.
This approach preserves the cell structure and nutritional material of the foodstuff, ensuing in a merchandise that, when rehydrated, very closely resembles the original foods.
The approach also stops the water from getting reabsorbed by the food and thus decreases its bodyweight significantly.
Most meals items this sort of as fruits, vegetables and meats are effectively-suited to freeze-drying, and can be utilised for prolonged-phrase foodstuff storage and preservation.
The Procedure of Dehydration
Dehydrating foods is a foods preservation technique which has been utilized for generations. Indigenous Us citizens dehydrated their buffalo kills in their looking camps to make it simpler to transport. Pemmican (a dehydrated concoction of buffalo meat combined with unwanted fat and berries) was a staple of numerous of the nomadic North American tribes. This reduced-heat dehydration procedure involved possibly air drying (with close by campfires), or sunshine drying strips of meat on drying racks.
Dehydrators are a modern technique for little by little getting rid of the humidity from foods with no actually cooking it. A downside of dehydration is the minimal volume of meals which can be dried at one time. The constructive facet of dehydration is that this approach of processing for foodstuff storage can be effortlessly carried out at house.
How Do These Two Strategies Impact the Food?
Freeze-dried foods maintain considerably of the authentic shade, form, aroma and freshness of fruits, greens and meats. Freeze-dried foods does not usually contain additives or preservatives, so it continues to be correct to its first form. And the search, texture and flavor of the foods stays after re-hydration.
As opposed to reduced-warmth dehydration, freeze-drying enables for the preservation of pre-cooked meals, such as recipes this sort of as soups, stews, stroganoff, and the like. An apparent gain is that because the meal was geared up in its entirety prior to freeze-drying, all you need to do is basically insert drinking water, then heat for a couple of minutes in buy to create sumptuous meals.
Rehydrating freeze-dried food will take just a few minutes, basically by introducing boiling drinking water. Some foods, like many fruits and greens, require no re-hydration prior to ingesting.
Dehydrated foodstuff shrink in the course of processing as the humidity is taken out. So the meals product itself is substantially scaled-down than its unique dimension.
The re-hydration time of dehydrated foods takes a bit for a longer time than freeze-dried, but it stills preferences like the unique type of the foods. Some dehydrated food items incorporate extra components to improve flavors or help in preservation. As with freeze-dried fruits and greens, dehydrated fruits and veggies can be eaten without any re-hydration.
Each strategies of meals preservation increase the lengthy-phrase storage daily life of foodstuff. Most commercially developed freeze-dried and dehydrated food items have a shelf life of fifteen to twenty several years, if appropriately packaged and saved in a awesome, dry surroundings.
In addition to their currently being a reputable resource of foods in an emergency or lengthy-time period survival scenario, because of their light-weight weight and simplicity of portability, these food items are also great for using on camping, climbing and searching excursions. They are also a clever selection to keep in an emergency street-aspect kit for the auto, or in your bug out bag.
If you pick to keep these foodstuff in your auto as component of an emergency package, make sure you keep in mind to rotate them periodically. Temperatures in a vehicle can attain extremes, the two sizzling and cold. Higher warmth as nicely as steady temperature fluctuations add to more quickly degradation of equally dehydrated and freeze-dried meals.
Which Variety is Better for Use?
Absolutely everyone is various, and every single person has their very own personal preferences and preferences. With that in head, there are a handful of issues to take into account prior to making a choice in between freeze-dried or dehydrated foods.
Residence-developed fruits and vegetables are greater preserved by means of dehydration, because the regular individual can not pay for the expensive equipment used in freeze-drying.
Food items used in everyday cooking and meal preparation must almost certainly be freeze-dried. This permits the foods to be speedily re-hydrated as it is cooked prior to serving. If accessibility and portability are essential, than both sort of preserved food need to fulfill individuals particular requirements. Once yet again, it really is a matter of personalized preferences.
In skewers , both dehydrated and freeze-dried foods are exceptional alternatives for long-phrase foods storage, as nicely as for day-to-day use or for climbing, tenting, and many others. They equally provide mild-weight, moveable, hassle-free meals. The major difference is that freeze-dried meals are inclined to greater maintain the form, texture and flavors of the unique meals.
Most men and women will find that a blend will work greatest for their needs. Single-item foods this kind of as vegetables, potatoes, and other staples and grains are well-suited to minimal-heat dehydration. Freeze-drying is far more proper for meats and fruits (whose texture can be preserved), and for pre-cooked meals with a assortment of components this sort of as soups, stews and sauces.