What is Freeze-Drying: A 101 Guide

What is Freeze-Drying: A 101 Guide

So you’ve been following our blog for a while now and reading all about our freeze-drying adventures! But you may be left wondering: what exactly is freeze-drying? 

As the internet’s freeze-drying experts, we’re here to give you all the facts about freeze-drying: what it is, how it works, and what you’re left with. If you want to learn about the science behind our freeze-dried experiments, keep reading! 

What is freeze-drying? 

Freeze-drying, in its simplest terms, is the process of removing all the moisture from a piece of food. You can freeze-dry candy, fruit, vegetables, and even complete meals! Here at that sweet lyfe, we’ve tried everything from Skittles to lemons to Christmas rum cake. We take these foods and, using our freeze-drier, remove all the water content to give you our tasty, delicious freeze-dried treats. 

So how exactly does it work? 

Freeze-drying is a bit more complicated than just removing the moisture from food. It’s an interesting process that involves three main steps: freezing, sublimation, and adsorption. These terms sound very technical, but read on to hear how they work! 

The first step is freezing. In this step, the food is frozen at extreme temperatures so that the water in the food turns into ice. This allows sublimation, the next step, to occur. 

In this step, you lower the pressure and raise the temperature. By doing this, the ice turns directly into a gas, instead of a liquid (this is what sublimation means). About 95% of the product’s water is removed in this step. 

The rest of the water is removed in the third step, adsorption. Here, the remaining water molecules are removed by raising the temperature even higher. 

These steps sound complicated, but here at that sweet lyfe, we like to use the Harvest Right freeze-dryer, which automates these steps and makes it super easy! 

What are you left with? 

After these three steps, you’re left with a tasty, yummy freeze-dried candy. When freeze-drying, almost none of the nutrients are removed from the food, so the flavour stays the same (sometimes it even gets sweeter!). By removing all the water from the product, the most noticeable change you’ll see is in the texture of the food. Remember our post about Jell-O? These candies turned into these super crunchy little bites. And Jolly Ranchers swelled up to about the size of a golf ball when we freeze-dried them (stay tuned for this review)! 

This is why we love freeze-drying. By changing the texture of our favourite candies, it’s like discovering a whole new treat! Candies that are normally soft become crunchy, and tiny candies turn into big bites. It helps us keep things new and exciting, so we never get bored of our favourite treats. 

As a plus, since freeze-drying removes the moisture from the food, it extends its shelf-life. Freeze-dried foods can last up to 25 years! This makes it a popular option for campers and adventurers, or anyone who wants their favourite snacks to last. 

Freeze-drying can seem like a mysterious process, but we hope this blog helped you understand the science behind it a little more. Not a science fan? Don’t worry – leave it to us, and just sit back and enjoy our delicious treats. 

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