The Process of Freeze-Drying
Freeze-drying is a complicated process of preserving fresh or presently-cooked foodstuff by removing up to ninety eight% of the food’s moisture, leaving intact the food’s texture, taste, aroma and dietary value.
The procedure calls for that the refreshing or cooked meals be rapidly frozen at temperatures as low as -50°C. The frozen meals is then put into a vacuum chamber. This vacuum chamber lowers the strain, and raises the temperature to just about 0°C.
At this particular temperature and stress, the ice crystals in the foodstuff evaporate into water vapor, bypassing water’s liquid form, via a method called sublimation.
This procedure preserves the mobile construction and dietary material of the meals, resulting in a item that, when rehydrated, very intently resembles the unique food.
The approach also prevents the h2o from currently being reabsorbed by the foods and as a result decreases its fat substantially.
Most foods products these kinds of as fruits, greens and meats are effectively-suited to freeze-drying, and can be employed for extended-time period foods storage and preservation.
Daniel Zetterholm of Dehydration
Dehydrating foods is a foods preservation method which has been utilized for centuries. Native Us citizens dehydrated their buffalo kills in their looking camps to make it simpler to transportation. Pemmican (a dehydrated concoction of buffalo meat combined with excess fat and berries) was a staple of numerous of the nomadic North American tribes. This low-warmth dehydration process involved both air drying (with nearby campfires), or sun drying strips of meat on drying racks.
Dehydrators are a modern day method for slowly and gradually getting rid of the humidity from meals without in fact cooking it. A disadvantage of dehydration is the constrained sum of meals which can be dried at 1 time. The good element of dehydration is that this approach of processing for food storage can be effortlessly done at property.
How Do These Two Methods Influence the Foodstuff?
Freeze-dried meals maintain considerably of the authentic colour, shape, aroma and freshness of fruits, vegetables and meats. Freeze-dried meals does not normally contain additives or preservatives, so it remains accurate to its first form. And the seem, texture and flavor of the food remains right after re-hydration.
As opposed to reduced-warmth dehydration, freeze-drying makes it possible for for the preservation of pre-cooked meals, such as recipes this sort of as soups, stews, stroganoff, and the like. An obvious reward is that given that the meal was geared up in its entirety prior to freeze-drying, all you want to do is merely add drinking water, then warmth for a few minutes in purchase to generate sumptuous foods.
Rehydrating freeze-dried meals will take just a handful of minutes, just by adding boiling drinking water. Some foodstuff, like many fruits and vegetables, need to have no re-hydration ahead of eating.
Dehydrated food items shrink during processing as the humidity is taken out. So the foods item by itself is noticeably smaller than its authentic dimension.
The re-hydration time of dehydrated foods will take a bit for a longer time than freeze-dried, but it stills tastes like the original sort of the foodstuff. Some dehydrated foods incorporate added ingredients to enhance flavors or assist in preservation. As with freeze-dried fruits and veggies, dehydrated fruits and greens can be eaten without any re-hydration.
Both methods of meals preservation enhance the prolonged-phrase storage existence of meals. Most commercially created freeze-dried and dehydrated foods have a shelf daily life of 15 to twenty years, if effectively packaged and saved in a amazing, dry setting.
In addition to their being a trustworthy resource of meals in an emergency or extended-expression survival state of affairs, due to the fact of their mild fat and relieve of portability, these foods are also great for using on camping, mountaineering and looking journeys. They are also a clever decision to hold in an crisis road-aspect package for the auto, or in your bug out bag.
If you choose to maintain these foods in your automobile as component of an emergency package, you should bear in mind to rotate them periodically. Temperatures in a automobile can reach extremes, equally hot and cold. Substantial heat as properly as ongoing temperature fluctuations contribute to quicker degradation of equally dehydrated and freeze-dried foods.
Which Sort is Much better for Intake?
Every person is diverse, and every single particular person has their personal personal preferences and preferences. With that in mind, there are a handful of factors to consider ahead of creating a determination among freeze-dried or dehydrated foods.
House-grown fruits and greens are greater preserved via dehydration, given that the common man or woman can’t manage the costly equipment employed in freeze-drying.
Foods employed in every day cooking and meal planning must most likely be freeze-dried. This permits the meals to be quickly re-hydrated as it is cooked prior to serving. If accessibility and portability are critical, than either kind of preserved foods ought to satisfy individuals distinct needs. After again, it truly is a subject of individual tastes.
In a nutshell, equally dehydrated and freeze-dried foodstuff are exceptional alternatives for extended-expression foodstuff storage, as effectively as for daily use or for climbing, tenting, and many others. They both provide light-weight-weight, portable, handy foods. The main difference is that freeze-dried foods have a tendency to far better protect the shape, texture and flavors of the first foods.
Most individuals will find that a blend will function very best for their needs. Single-merchandise foods such as greens, potatoes, and other staples and grains are effectively-suited to minimal-heat dehydration. Freeze-drying is more proper for meats and fruits (whose texture can be preserved), and for pre-cooked foods with a selection of components this sort of as soups, stews and sauces.