The Science Behind Freeze Drying and Its Preservation Effects
Our on-the-go lifestyle has turned to packaged foods, and freeze dried foods have been one of the most successful hits of the past few years. Wonder what happens to that delicious strawberry to become that delectable dark brown nibblet in a matter of seconds? Well, let's take a peek at this prolific process.
101 to Freeze Drying
Imagine your favourite piece of fresh fruit, or a bar of your favourite chocolate, frozen for a year, and then retaining the exact flavour, colour and vitamin level it had on the day it was frozen; sounds like a fraud.
The Freeze Drying Process
What's different about a freeze-dryer – also known as a lyophyliser (‘lyo' for short) – then? Well, it's a multistage process, first: you freeze the product and then, once it's frozen, you lower the pressure around it and apply heat so the frozen water sublimes.
Pre-Freeze Phase
First, the food is super-chilled – quickly frozen below the point of freezing; the tiny ice crystals formed are the same size and shape.
Primary Drying Phase
Just putting the frozen food into the vacuum isn't enough. Then again, some gentle heating can get it off to a head start …The liquid phase is short‑circuited; the ice crystals skip past it subliming straight from ice to vapour.
Secondary Drying Phase
Only at the end of this process do higher temperatures remove any water molecules trapped within as the food is evacuated, completing the desiccation.
Why Choose Freeze Drying?
The important point is that, being preserved, the integrity of the food form remains perfectly preserved, that is, taking account of its shape and colour and - and most importantly - of its nutritional value. There is no damage to the food and the product quality is unchanged, which could not be said for other drying processes.
The Science of Freeze Dried Food
The upshot was a shatterable product indistinguishable both in nutritional value and storage needs from its freshly picked version. For years it could be stored in the cupboard, out of refrigeration, with the help of a little plastic to keep it airtight Candy, anyone? Meats? Greens? The examples are infinite.
Freeze Dried Candy: How Cool and Where to Buy It?
And even the world of candy isn't safe; in fact, freeze-drying candy is just another way that this process is poised to take over. The satisfying crunchiness of dried fruit applies just as well to candy, turning an already sweet food into somehow more of a snack. Shop Here at Freeze N Dried.
The Delight of Freeze Dried Fruit
Since freeze drying retains most of the nutrients, the reduced water content merely serves to concentrate the natural sugars present in the fruit, so that the end product of freeze drying is sweeter than the original fruit specimen.
Freeze Drying vs Processed Foods
Many of us eat processed foods daily, but what are they?
What are Processed Foods?
Processed foods are foods that have been altered in some way during preparation: the problem is that these additions and alterations result in the loss of nutrients and the introduction of additives that are bad for you.
Comparing the Nutritional Value
In contrast, freeze drying retains the nutritional content, making it a healthier choice.
The Magic of Rehydration
Bringing back the moisture to foods that had no moisture to begin with is really just a small incremental step to creating a cheap, quick and effective freeze-dried food system.
Let's Sum Up so You don't Forget!
Hardly a more persuasive scientific procedure to maintain a food's taste, texture, colour, and nutrients, and a vision of ease and sustenance for an endless period of time. When it comes to freeze dried fruits to sweets, convenience never tasted so nourishing.
Frequently Asked Questions
1. Will we eat dehydrated, or freeze dried food straight from the pouch?
You can if you like, but most people prefer to rehydrate.
2. When freeze-dried, are bacteria still present?
Ah, it can be used to kill some gram-negative bacteria, but it's not a valid replacement for cooking or pasteurisation.
3. Could all our food be freeze dried and still be healthy?
While the nutrients are retained in the food for the freeze drying process, it will be as healthy as the food you eat originally.
4. Are foods that are preservated by freeze drying tasty?
Yes, those freeze-dried foods can be — tend to retain most of the flavours from the original produce, and even improve on the taste with a distinctive pleasing crunch.
5. Are freeze dried foods expensive?
Although dried food is expensive than the regular foods in market because it is prepared trough an extensive finishing , it is worth to buy.