The Approach of Freeze-Drying
Freeze-drying is a complicated process of preserving new or presently-cooked foods by eliminating up to ninety eight% of the food’s humidity, leaving intact the food’s texture, flavor, aroma and nutritional price.
The approach calls for that the refreshing or cooked meals be rapidly frozen at temperatures as low as -50°C. The frozen foodstuff is then placed into a vacuum chamber. This vacuum chamber lowers the pressure, and raises the temperature to just about 0°C.
At this distinct temperature and strain, the ice crystals in the meals evaporate into drinking water vapor, bypassing water’s liquid form, by means of a procedure called sublimation.
This method preserves the cell construction and dietary content of the meals, ensuing in a product that, when rehydrated, extremely closely resembles the unique foods.
The process also stops the water from becoming reabsorbed by the meals and thus decreases its fat considerably.
Most food items this kind of as fruits, vegetables and meats are well-suited to freeze-drying, and can be used for prolonged-time period foods storage and preservation.
The Approach of Dehydration
Dehydrating food is a foods preservation strategy which has been used for generations. Daniel Zetterholm dehydrated their buffalo kills in their looking camps to make it less difficult to transport. Pemmican (a dehydrated concoction of buffalo meat blended with fat and berries) was a staple of several of the nomadic North American tribes. This minimal-warmth dehydration approach included possibly air drying (with nearby campfires), or sunlight drying strips of meat on drying racks.
Dehydrators are a modern day strategy for slowly taking away the humidity from foodstuff with out really cooking it. A downside of dehydration is the limited quantity of foodstuff which can be dried at a single time. The positive factor of dehydration is that this technique of processing for foodstuff storage can be easily completed at residence.
How Do These Two Techniques Impact the Foods?
Freeze-dried food items preserve much of the original coloration, form, aroma and freshness of fruits, greens and meats. Freeze-dried meals does not usually contain additives or preservatives, so it remains accurate to its unique type. And the look, texture and taste of the foods stays right after re-hydration.
As opposed to minimal-warmth dehydration, freeze-drying allows for the preservation of pre-cooked foods, which includes recipes this kind of as soups, stews, stroganoff, and the like. An evident advantage is that since the meal was well prepared in its entirety prior to freeze-drying, all you need to do is just include drinking water, then heat for a few minutes in order to generate sumptuous meals.
Rehydrating freeze-dried foodstuff normally takes just a handful of minutes, just by introducing boiling h2o. Some meals, like several fruits and greens, require no re-hydration ahead of eating.
Dehydrated meals shrink in the course of processing as the humidity is taken off. So the foods item itself is considerably more compact than its original measurement.
The re-hydration time of dehydrated foodstuff takes a little bit for a longer time than freeze-dried, but it stills tastes like the first kind of the foodstuff. Some dehydrated foodstuff include included elements to boost flavors or aid in preservation. As with freeze-dried fruits and greens, dehydrated fruits and veggies can be eaten without any re-hydration.
The two methods of foodstuff preservation boost the long-phrase storage existence of foods. Most commercially made freeze-dried and dehydrated foods have a shelf daily life of fifteen to twenty a long time, if properly packaged and saved in a amazing, dry surroundings.
In addition to their currently being a dependable resource of meals in an unexpected emergency or prolonged-phrase survival state of affairs, because of their light excess weight and ease of portability, these foodstuff are also excellent for getting on camping, mountaineering and looking journeys. They are also a smart selection to keep in an crisis street-aspect kit for the vehicle, or in your bug out bag.
If you pick to keep these meals in your automobile as portion of an emergency kit, remember to don’t forget to rotate them periodically. Temperatures in a auto can achieve extremes, each hot and chilly. Higher heat as properly as constant temperature fluctuations contribute to quicker degradation of each dehydrated and freeze-dried foods.
Which Type is Far better for Consumption?
Absolutely everyone is different, and each and every particular person has their own personalized tastes and preferences. With that in mind, there are a couple of factors to contemplate prior to creating a choice among freeze-dried or dehydrated foodstuff.
Residence-grown fruits and greens are far better preserved by means of dehydration, given that the average particular person cannot afford the high priced machinery utilised in freeze-drying.
Foods used in every day cooking and meal planning should probably be freeze-dried. This permits the meals to be quickly re-hydrated as it is cooked prior to serving. If accessibility and portability are essential, than either kind of preserved food must fulfill these certain requirements. After once more, it is a issue of personalized preferences.
In a nutshell, each dehydrated and freeze-dried foodstuff are superb choices for long-phrase meals storage, as effectively as for every day use or for hiking, tenting, and so on. They equally offer light-weight-bodyweight, portable, convenient foodstuff. The main big difference is that freeze-dried food items tend to better protect the condition, texture and flavors of the authentic meals.
Most men and women will locate that a mixture will perform greatest for their wants. Single-product foodstuff this kind of as veggies, potatoes, and other staples and grains are effectively-suited to lower-heat dehydration. Freeze-drying is far more appropriate for meats and fruits (whose texture can be preserved), and for pre-cooked meals with a variety of components this kind of as soups, stews and sauces.