According to the public relations of the Research Institute of Food Science and Technology, "Dr. Salehi", while visiting this research institute unveiled a freeze-dryer designed by the academic staff of the Institute
The director of the Food Machinery Department, Dr. Seyed Mehdi Mirzababaei, explaining the importance of the design and construction of this device stated that "Every year, about 35% of agricultural products are wasted; however, this amount could be reduced by applying such alternate industries as this machine.
He continued: "Drying food products can have a significant effect on reducing agricultural waste." The industry can be implemented in many areas, such as home-made dried fruit production, so it can expand rapidly in the society.
He stated that "Currently, the best way to increase the shelf life of products is the freeze-drying method.”
Dr. Mohsen Heydari, a member of the academic staff of the Institute and the supervisor of this research project, also said in this regard: “In the freeze-drying process, the products are first frozen. Freeze-drying operations are generally performed in a vacuum environment. Therefore, the dried products in this method, in addition to complete removal of moisture content, aroma, taste, color and appearance of the product are preserved and heat-sensitive nutrients suffer the least damage.
However, in recent years, the process of freeze-drying at atmospheric pressure has received much attention from researchers due to the reduction of process costs and has even been used on an industrial scale in some countries. This method is one of the fields of study in the Research Institute of Food Science and Technology and the first samples will be made in the near future.
Heydari, while stating that the device is based on a vacuum environment and is special for food, added that this device can reduce the cost of production to about 35%. "The difference between the current device and the existing sample is that it is based on drying a wide range of food, while the other samples are designed for general applications and their technical specifications are often more than necessary, which makes them more expensive.
The administrator of this research project stated about the features of the device made at RIFST "It has two modes, automatic and manual. In this device, drying programs designed for food with different geometries. In automatic mode, a special program is applied to it by selecting the product type. The effectiveness of drying programs designed for food has been evaluated in several experimental studies. The results of studies show that the drying time of food, thanks to the programs applied, has been reduced by up to 50%, compared to other devices.
This device has unique features in manual mode that are intended for use in study and research environments. The freeze-drying process consists of three stages of freezing, primary and secondary drying.
The device is capable of freezing food to -40oC for three hours. In manual mode, it is possible for researchers to change the freezing temperature and the rate of temperature reduction according to the type of study material, if necessary. Researchers can examine their study conditions by defining the curve of changes in freezing temperature over time using the device.
The dryer chamber is equipped with heaters that allow the chamber temperature to be increased up to 200oC. In the manual mode, researchers are given the opportunity to define the temperature change curve of the dryer chamber and to find the best way to dry the products by examining the different conditions of the rage.
He added: the price of the device is about a quarter of the imported products and its production in the country will lead to currency savings.
Finally, he said: "Due to the successful implementation of this technological project, the Food Science and Industry Research Institute has the ability to design and manufacture these devices for other food products on a laboratory, semi-industrial and industrial scale."