The latest application knowledge of frying oil filter

In China's thousands of years of food culture, fried food has always been an important component. Deep-fried foods have been loved by the general public because of their special flavor and taste. In the past two decades, the living standards of the Chinese people have been continuously improved, and the leisure food industry has prospered. Fried foods are the main component of snack foods. In the food processing often mentioned, frying is a common and common method of processing.

However, with the standardization of the market and the improvement of food processing supervision laws and regulations, people’s requirements for food hygiene and safety are also increasing. How to extend the service life of frying oil and how to ensure the safety of frying oil has become a serious issue for fried food processing technicians.

The standard of edible oil

China has already established a standard analytical method (GB/T5009.37-1996) for the hygienic standard of edible frying oil (GB7102.1-94) and the hygienic standard for edible oils and fats, and the parameters such as the acid value, carbonyl value, and peroxide value of oils and fats. , as well as inspection methods made strict regulations. However, many fried food manufacturers in China have not paid enough attention to this issue. Although they all know that the use of rancid oil fried foods will seriously affect product quality and shorten the product's shelf life. However, due to the failure to find suitable and effective equipment and methods, many manufacturers have to regularly clean out the larger carbide residue in the oil pan, add some new oil, or replace the new oil and other methods to maintain normal production activities .

Physicochemical indexes of edible vegetable oil during frying (GB7102.1-94)

1. The sensory index of edible vegetable oil during frying: It has the color, smell and taste of vegetable oil during normal frying of various foods, and there is no odor, impurity and residue. 2. Physical and chemical indicators of edible vegetable oil during frying

The mechanism and influence of edible oils and fats

Many Chinese and foreign scholars have found that carbonized residues (such as fine flour and starch granules), peroxides and high-molecular polymers suspended in oils and greases are catalysts for the oxidation reaction and hydrolysis reaction of oils and fats. If these catalysts can be effectively removed in time to prevent their catalytic action due to repeated heating, the process of deterioration of the grease will be slow.

Another school of thought believes that most of the deteriorating reactions such as oxidation and hydrolysis of lipids are centered around particles. When these particles are removed, the reaction loses its center and the reaction speed becomes significantly slower. The diameters of these catalysts and particles are very small, most of which are between 5 and 10μ. Most of these particles are suspended in frying oil and are extremely difficult to remove by simple precipitation methods.

Due to the inability to remove fine suspended particles and high-molecular polymers, it is not effective in solving the problems of deterioration of fats and oils, accumulation of polymers and toxic substances. Frying oil often produces excessive acid values ​​and peroxide values, which greatly increases production costs. Moreover, the fine particles that are invisible to the naked eye suspended in the frying oil are often charred and extremely easily adhere to the surface of the fried food. This is why fried foods gradually change to deep colors as frying oil is used.

Therefore, in the process of food frying, the frying oil used for frying the food is continuously heated at a high temperature in the presence of air, moisture, and food residue, and the grease generates a series of complicated chemical reactions such as polymerization, decomposition, and oxidation. Oil is oxidized to acid, and oil is hydrolyzed to generate acid. Once the free fatty acid content exceeds 0.5%-1.0%, the hydrolysis rate increases.

If the acid value is too high, the smoke point of the oil is reduced, and smoking is easily caused thereby affecting the flavor of the fried food. In the absence of oxygen, oil molecules will polymerize to produce cyclic compounds and polymers with high molecular weight. These substances increase the viscosity of the oil, lower the heat transfer coefficient, increase the oil absorption rate of the food, and make the oil content of the fried product. Increased. Foods with a large amount of oils and fats, due to air, sunlight, microorganisms, enzymes, etc., can easily lead to bad odors, make fried foods taste bitterer or even more toxic. This phenomenon is called rancidity.

How the oil filter works

In recent years, many people engaged in food processing and oil and fat research have attempted to use chemical methods and use various antioxidants to suppress the rise in acid value and peroxide value. However, due to temperature control, oil-water mixing and other factors, the effect is still Not very ideal. The use of physisorption and precision filtration methods to achieve the purpose of inhibiting the increase in acid value and peroxidation value is a more convenient method that is more consistent with food processing safety.

In recent years, fried oil filters have been developed at home and abroad. Guangzhou Zhongtian Food Packaging Machinery Co., Ltd. is one of the typical representatives. They tried to filter out high-temperature frying oil in the form of high-density frying oil polymer, peroxides, suspended particulates and other impurities in the reaction of the catalyst, thus inhibiting the acid value and peroxide in frying oil. The value increases.

Due to the usual filtration method using general filtration equipment, such minute impurities cannot be filtered out. In order to achieve a very precise filtration effect of 5μ or more, Guangzhou Zhongtian Food Packaging Machinery Co., Ltd. has taken the lead in the development and production of Zhongtian-brand frying oil filter, focusing on the complete filtration of suspended particles and impurities. It not only meets the requirement of high precision, but also is suitable for operating at a high temperature of 185°C-200°C. It also meets the need for large industrial filtration.

In the filtration operation, as the filtration pressure difference increases, the pores of the compressible filter residue will become narrower and the fluid resistance will increase, sometimes the pores will be blocked due to the fine particles, which will affect the smooth progress of the filtration process.

To prevent this from happening, Zhongtian brand frying oil filter coated on the filter paper has a very strong surface activity, has a strong dynamic positive charge, can adsorb polar polymers such as high molecular polymers, peroxides, etc. Cluster and particulate filter aids.

As it constitutes the framework of the filter residue, a relatively loose filter residue is formed, so that the grease can be passed through smoothly. Together with the special filter paper has a very high porosity and good air permeability. It can effectively filter out particulate impurities, carbides, polymers and other harmful substances that are suspended in frying oil by more than 5 microns.

The practice of using hundreds of fried food manufacturers at home and abroad has proven that the frying oil filter can effectively improve the frying environment of food, inhibit the increase of acid value and peroxide value, increase the shelf life of fried foods, and prolong the frying. The life of the oil. In order to improve product quality and save production costs.

Oil Filter Workflow

The oil filter can be connected to the production line, or it can be used as a mobile device with several oil pans. These can be based on the actual production of the customer and make the optimal combination.

The main function of frying oil filter

1. The oil filter can effectively improve the appearance quality of fried foods. Because the particulate impurities suspended in frying oil are filtered out, the frying environment is significantly improved. Fujian Foods Co., Ltd. Southern Foods Co., Ltd. has stated in the oil filter test report that after the oil filter equipment was used, the fine brown-black particles of palm oil in the fryer were adsorbed by filter aids. The filter aids and filter paper retained significant brown-black impurities. The use of the oil filter device can effectively remove the fine solid impurities in the palm oil, so that the oil becomes clear and bright, and the color of the fried and expanded food becomes significantly lighter.

2. The oil filter can extend the shelf life of fried foods. As the device can effectively suppress the increase of frying acid price, food shelf life is guaranteed. Wangwang Food Group Hangzhou Branch made a graph of acid price changes based on data from the laboratory before and after the oil filter unit. Laboratory data showed that the use of oil filters played a significant role in suppressing the rise in frying acid price. It is of great significance to improve the frying environment, improve product quality, and extend the shelf life of products.

3. The oil filter can save the production cost, because the filter organic extended the life of the frying oil. In general fried food enterprises, after using frying oil two or three days later, the oil has turned black and thickened, the acid price has exceeded the standard, and it has to be abandoned. After using an oil filter, it can be used for fifteen days or more, greatly reducing production costs.

4. The oil filter can increase the heat efficiency of the heat exchanger and save energy. As the frying oil polymer polymer and other colloidal impurities are continuously filtered out, the viscosity of the oil is reduced, and the dirt in the heat exchanger tube wall is greatly reduced, thereby improving the heat transfer efficiency and saving energy.

5. Improve the taste of fried foods. As the viscosity of the frying oil is greatly reduced, the oil content of the fried food is effectively controlled. The food is more brittle and its greasy feel is reduced.

6. More in line with environmental requirements. The treatment of waste cooking oil is currently more stringent in advanced Western developed countries. There is reason to believe that people's environmental awareness will inevitably be greatly improved in the process of further integration with China. From the perspective of corporate social responsibility, we should promote the protection of the environment and minimize the discharge of waste. The role of the frying oil filter in reducing the consumption of frying oil is quite significant.