The Method of Freeze-Drying
Freeze-drying is a complex procedure of preserving clean or previously-cooked meals by taking away up to ninety eight% of the food’s humidity, leaving intact the food’s texture, taste, aroma and nutritional price.
The method demands that the clean or cooked foodstuff be quickly frozen at temperatures as reduced as -50°C. The frozen foodstuff is then positioned into a vacuum chamber. This vacuum chamber lowers the strain, and raises the temperature to just about 0°C.
At this specific temperature and strain, the ice crystals in the meals evaporate into water vapor, bypassing water’s liquid kind, through a process known as sublimation.
This process preserves the cell composition and dietary articles of the meals, resulting in a item that, when rehydrated, extremely carefully resembles the original foods.
The approach also stops the water from being reabsorbed by the foodstuff and as a result decreases its excess weight drastically.
Most food items this sort of as fruits, vegetables and meats are nicely-suited to freeze-drying, and can be utilized for lengthy-expression meals storage and preservation.
The Method of Dehydration
Dehydrating foodstuff is a foods preservation approach which has been employed for hundreds of years. Native Us citizens dehydrated their buffalo kills in their searching camps to make it less difficult to transport. Pemmican (a dehydrated concoction of buffalo meat mixed with body fat and berries) was a staple of several of the nomadic North American tribes. This minimal-heat dehydration procedure included both air drying (with nearby campfires), or sunshine drying strips of meat on drying racks.
Dehydrators are a modern strategy for slowly and gradually removing the dampness from foodstuff with out actually cooking it. A downside of dehydration is the limited volume of foods which can be dried at one particular time. The optimistic element of dehydration is that this technique of processing for food storage can be effortlessly accomplished at property.
How Do These Two Strategies Affect the Food?
Freeze-dried foodstuff protect a lot of the unique shade, shape, aroma and freshness of fruits, vegetables and meats. Freeze-dried foodstuff does not normally have additives or preservatives, so it continues to be correct to its original type. And the appear, texture and taste of the food continues to be following re-hydration.
Not like minimal-heat dehydration, freeze-drying makes it possible for for the preservation of pre-cooked meals, like recipes such as soups, stews, stroganoff, and the like. An clear benefit is that given that the meal was well prepared in its entirety prior to freeze-drying, all you need to have to do is merely incorporate drinking water, then warmth for a number of minutes in order to generate luxurious meals.
Rehydrating freeze-dried foods will take just a few minutes, merely by introducing boiling h2o. Some meals, like a lot of fruits and veggies, require no re-hydration before ingesting.
Dehydrated foodstuff shrink in the course of processing as the humidity is removed. So the foodstuff merchandise by itself is significantly smaller sized than its unique dimension.
The re-hydration time of dehydrated foods normally takes a bit longer than freeze-dried, but it stills preferences like the original form of the foods. Some dehydrated foodstuff include added substances to enhance flavors or support in preservation. As with freeze-dried fruits and vegetables, dehydrated fruits and greens can be eaten without having any re-hydration.
Daniel Zetterholm of meals preservation enhance the long-expression storage existence of food. Most commercially developed freeze-dried and dehydrated foods have a shelf daily life of fifteen to twenty a long time, if correctly packaged and stored in a awesome, dry atmosphere.
In addition to their being a dependable source of meals in an crisis or long-expression survival situation, since of their light excess weight and relieve of portability, these food items are also great for taking on tenting, climbing and looking excursions. They are also a sensible selection to hold in an unexpected emergency highway-side kit for the auto, or in your bug out bag.
If you choose to hold these foods in your automobile as portion of an crisis kit, you should remember to rotate them periodically. Temperatures in a automobile can get to extremes, the two scorching and chilly. High warmth as nicely as constant temperature fluctuations add to a lot quicker degradation of both dehydrated and freeze-dried meals.
Which Kind is Far better for Intake?
Absolutely everyone is diverse, and every man or woman has their own personal tastes and tastes. With that in thoughts, there are a couple of issues to consider just before generating a selection between freeze-dried or dehydrated foods.
Home-grown fruits and veggies are far better preserved through dehydration, considering that the average individual can’t afford the high priced machinery utilised in freeze-drying.
Foods utilised in daily cooking and food planning must most likely be freeze-dried. This permits the foodstuff to be quickly re-hydrated as it is cooked prior to serving. If accessibility and portability are critical, than possibly sort of preserved foods ought to satisfy these distinct wants. When once again, it really is a issue of personalized preferences.
In a nutshell, each dehydrated and freeze-dried food items are exceptional alternatives for prolonged-phrase foodstuff storage, as effectively as for everyday use or for mountaineering, camping, and so on. They each give mild-excess weight, portable, handy foods. The major variation is that freeze-dried foods are likely to greater protect the shape, texture and flavors of the unique foodstuff.
Most people will locate that a combination will function very best for their needs. Single-product food items this kind of as veggies, potatoes, and other staples and grains are effectively-suited to low-warmth dehydration. Freeze-drying is far more suitable for meats and fruits (whose texture can be preserved), and for pre-cooked meals with a selection of ingredients this kind of as soups, stews and sauces.