Methods of Drying Food

Posted by Rajnikant on July 4th, 2019

Drying is one of the oldest means of preserving food. Even today people dry fishes, vegetables and fruits in many different ways to use them well past their use-by date. What has changed is the way we dry our food. From drying in sun, today we use large industrial drying oven for this purpose. The demand for dried food has also gone up significantly. Today dried food is an important part of grocery shelves by themselves or as part of an entire dish, such as instant noodles.

While sun drying is still followed in cottage industries or for domestic purposes, the industrial sector largely depends on drying oven manufacturers for their production facilities. The drying oven is the most efficient means because you can control the heat and hasten the process. For industrial purposes, it can make a major difference because it allows efficiency and quick turnaround.

Different drying methodologies

Sun drying

This is one of the oldest methods of preserving food. The culture of drying food can be seen across almost every community in the world. It was the best way to preserve certain food and ensure they were available out of season. Dried food was often the only source of nutrition for people living in harsh conditions, such as dessert communities. It was also the favored means for travelers, such as fishermen or nomads who could not get access to fresh food regularly.

But the drying of food was not just a matter of necessity. It was also often about choice. People who had access to fresh produce sometimes chose to dry certain foods in order to enjoy them off-season or to eat their dried version. Dried food has a distinct taste. Some dishes depend on the drying of food, such as pickles. Many people even today choose to dry their food in the sun. However, it is largely a domestic method. From an industrial point of view it is too slow and inefficient.

Solar drying

Solar drying was developed to make sun drying more efficient. In this method we use specially constructed solar dryers to use solar energy. The dehydrator has a foil surface for better heat transfer and a ventilator to speed up drying time. Although, the drying time is faster than sun drying, it is rarely adequate for large scale industrial operations.

Freeze drying

This is a relatively new technology where we use cryodesiccation or lyophilisation to dry perishable food. We freeze the product, lower pressure and then remove any ice that is formed by the sublimation process. This can be a very effective method as the quality remains quite good. It is often used for preserving readymade meals.

Industrial oven

This is the most efficient means of drying food and used extensively in the food industry. For drying oven manufacturers, food drying is among their most common applications.Any oven can act as a dehumidifier, using that to dry food. However, the domestic oven is still pretty inefficient because in the absence of a fan it does not allow air movement. Industrial oven are built in large scale with maximum heat efficiency. Exhaust fans and air inlets allow for the movement of air. There is also a proper ventilation system that further adds to the oven efficiency.

The advantage of oven drying:

-    Better control of heat and moisture. We can adjust the temperature and the conditions inside the compartment.

-    We can achieve uniform heating of the food since the temperature and other conditions remain constant.

-    Heating can be achieved very rapidly. This increases our line speed.

-    It is the most efficient system because we can dry a large amount of food in a small time.

-    It allows efficient use of space. Some ovens have racks where a large quantity of food can be stacked for maximum use of space. This is not possible in many other drying methods.

-    Rapid line speed adds to the overall efficiency. The production values are unparalleled.

These are just some of the advantages offered by drying oven manufacturers. You can also customize the design for specific results.