What is Freeze-Dried Cat Food?
19th May 2021
Pet owners are becoming increasingly more concerned about what they are feeding their four-legged family members .
A relatively new trend that is becoming more and more popular amongst pet food manufacturers is freeze dried pet food and snacks.
We will explain what freeze-dried means whilst looking at some of the pros and cons of the freeze-dried approach when it comes to feeding our pets.
What does Freeze-Dried mean?
Freeze drying, which can also be referred to as lyophilisation or cryodesiccation.
It’s a low-temperature dehydration process that
involves freezing a product, lowering pressure, and then removing the ice by
sublimation.
The Freeze-Dried Process Explained
The exact process of freeze-drying is split into 3 key steps.
Step 1: Freezing Phase. In this step, the products are exposed to temperatures around -4.5°C to -8°C
Step 2: Sublimation. The pressure in the machine is lowered creating a vacuum effect around the food. The trays that the foods are laid on gradually warm causing the water to sublimate.
This means that the ice in and on the food turns into vapour which is then vacuumed out of the machine.
Step 3: Adsorption. During this phase, the temperature is raised slightly (still below 0°C) and the rest of the non-frozen molecules are removed. This whole process removes around 95% of the moisture in the food.
There may be some vitamin % lost from the food at this stage, however, the food still restores a lot of its nutritious value compared to some other food processing techniques.