Description

Vacumn Fried Fruits

Vacumn Dried Fruits

Vacuum drying method

Vacuum drying is a drying method in a near-vacuum environment (currently, scientists cannot create a vacuum environment but only a near-vacuum environment).

The dried material is put into a closed chamber, then a vacuum pump is used to create a vacuum environment. The vacuum environment we create has a very small pressure, about 50mmHg (The environment on Earth has a pressure of 760mmHg).

In a low pressure environment, water will boil at a very low temperature of about 30-40 degrees Celsius. When water boils, it means that water evaporation occurs very quickly, causing the object to dry faster than with conventional heat drying.

Low drying temperatures also help the output product retain its color and flavor better. Not only that, it also maintains the physical structure of the product.

Freeze drying method

Freeze drying is a more complicated drying method than vacuum drying. Vacuum drying is the final stage of freeze drying, so many people mistakenly think vacuum drying and freeze drying are the same thing.

Freeze drying has two main processes:

First, people will put the dried object into a cold room and quickly freeze it at very low temperatures -40 – -80 degrees Celsius.Then the dried object is put into the vacuum drying chamber and dried like the vacuum drying method.

The dried material is frozen before vacuum drying:

The difference between freeze drying and vacuum drying is the process of freezing the dried object. When the water in the dried product is in a solid state, immediately put into the vacuum dryer, the water will change to a gaseous state without changing to a liquid state as usual. That is sublimation.

When freeze drying, the dried object will freeze almost immediately, which helps the dried object retain its physical structure better than with vacuum drying. After drying, only the water in the product is sucked out, so it retains many nutrients, color and crispness.