Industrial drying of fruit has opened its place in the food industry today due to the progress of science and technology. Various people have been able to start their own business and earn income with this method. In this article, information about the method and challenges of industrial drying of fruits is provided for the dear readers of iFoods blog.
An introduction to drying fruits
Fruits have a great impact on human diet and nutrition. Fresh fruit contains more than 80% water and is highly perishable. Due to the fact that fruits are rich in nutrients, phenolic compounds and vitamins and their limited availability throughout the year, it is necessary to use methods to preserve and preserve fruits with the highest quality. One of the oldest methods of preserving food, which aims to increase the shelf life by reducing the humidity to a suitable level, is drying. Dried fruits are a group of foods that are called natural candy because of their nutritional value and taste.
Traditional methods of drying fruits
Among the home methods of drying fruits, we can mention the use of a heater or an oven. Another drying method is drying by sunlight, which is called natural drying. Considering that in drying by the sun, uncontrolled factors such as climate change, pollution by insects, dust and animal excrement, lack of access to sunlight, the need for a lot of space and long drying time, in the absence of careful management We will not produce a standard product, so nowadays the use of drying methods with multiple equipments called artificial dryers is on people’s agenda.
The difference between dried fruit and chips
Since dried fruits have a better and higher nutritional value than chips and also have a more favorable taste from the point of view of consumers (especially children), it is better to replace dried fruits with chips.
Changes that happen to fruits after drying
After the moisture of the fruit is taken by the sunlight or the machine, the nutrients of that fruit are changed to some extent. But this does not mean that dried fruit has no value. Dried fruit has a lower amount of vitamin C, but vitamins A, B and mineral salts are preserved in it and are not destroyed. Dried fruit is not different from its fresh varieties in terms of energy. Of course, because dried fruits have a smaller volume than fresh fruits and they are easier to eat, our stomach is able to accept more of them, and accordingly, more calories, carbohydrates, and nutrients enter the body. Among the types of dry fruits, figs, bananas and persimmons are the most energetic and kiwi the least energetic.
Advantages of industrial fruit drying
Unfortunately, the quality of products dried by the traditional method is greatly reduced compared to the raw material, so it is suggested to use alternative and newer methods. Among these methods, we can mention the use of a hot air device. These devices have different types. The way the fruit dryer works is in such a way that it dries the fruits without burning them by uniform heating. Of course, some of these devices operate at a lower temperature to prevent the loss of minerals inside the fruits.
Various components of industrial fruit drying machines
In general, fruit drying machines consist of three main systems, which include heating elements, fan, main body and tray. During the drying of the fruits, the thermal elements are turned on first. Then, with the help of a fan, the heat is evenly spread inside the device and causes the fruits to dry. Then, this moisture is taken out of the device through the fans.
Duration of fruit drying in industrial method
The duration of fruit drying depends on the following factors:
The amount of moisture in the fruit that is dried, the amount of environmental humidity and the power of the fruit dryer.
Depending on the type of fruit and fruit dryer, it takes about a day for the fruits to dry completely. If you intend to dry a large amount of fruit, using fruit drying machines is one of the best options.
Important points in industrial drying of fruit
To get the desired result, it is necessary to use good quality fruit. The fruits you choose for drying should be fresh and ripe. An odorless and colorless product is obtained from unripe fruits. The product obtained from overripe fruits becomes hard or soft and loose.
How to prevent fruit color change in fruit drying by industrial method
Some fruits may change color and darken (browning) due to drying. To prevent this, we use pre-treatment operations.
Pretreatment can prevent browning during drying and storage. It also increases the speed of drying of fruits. Fruits such as apples and peaches darken when sliced and exposed to air. This color change continues after drying and during storage. Among the pre-treatment methods are the use of substances such as lemon juice, citric acid, ascorbic acid (vitamin C) and… depending on the type of fruit. The duration of treatment depends on the type and size of the fruit. When the fruit slices are removed from the solution, the slices should be placed on a colander to remove excess water. As a result, the drying time is reduced.
The points that need to be taken into account when drying fruit with a fruit drying machine
- In order for drying all fruits to take approximately the same time, the fruits should be sliced in similar sizes.
- You can use slicer devices to have parts with more accurate and uniform sizes.
- Using a fruit dryer makes the fruit juice evaporate slowly and at a very low temperature. Most of the fruit drying machines have an electric element in the bottom, on which a fan is placed.
Important points in using industrial fruit dryer
To use the fruit dryer, set the machine to the fruit drying setting and place the fruits in the dryer. Depending on their type and thickness, the fruits in this device need between one and two days to dry. . Finally, collect the dried and crunchy fruits. Dried fruit should be relatively hard because their moisture has been lost.
Important points in the storage of dried fruits
One of the most important stages of fruit drying is its storage method after drying. For this reason, it is recommended to pay attention to the following things when storing fruit chips:
Store the dried fruit in a dry place with a low temperature and away from the humid environment.
The ambient temperature should be less than 7 degrees Celsius, but it should not be kept in the refrigerator or freezer because it causes a sharp decrease in nutritional value.
It is better to store them in a closed glass container or a paper envelope.