In the process of fruit juice production and processing, effective sterilization is essential. Ultraviolet (UV) disinfection technology, as a universal disinfection treatment method, is gaining more and more recognition. Ultraviolet rays kill microorganisms by destroying their DNA structure. Ultraviolet disinfection technology can avoid the use of chemicals and can be used to disinfect water, syrup, clean water, wastewater, filtration systems, and packaging surfaces. At the same time, the installation and maintenance of the UV system is very simple and convenient.
Principle of UV disinfection
Ultraviolet light is an electromagnetic wave between visible light and X-ray. The wavelength range is 185-400nm. Ultraviolet light (also called UV-C) in a special wavelength range has a strong sterilization effect and reach a peak at UV 265nm. The strongest. Ultraviolet rays kill microbial tissues by penetrating cell membranes and destroying DNA, rendering them unable to reproduce and effectively destroying them.
A typical ultraviolet disinfection system is to install an ultraviolet lamp tube in a quartz protective sleeve in a stainless steel cylindrical cavity. Let the treated liquid enter from one end of the cavity and flow out from the other end. In fact, any liquid can be effectively treated with ultraviolet light, including untreated pipe water, process water after treatment, sewage, fruit juice and syrup, etc.
Based on the type of ultraviolet lamp, ultraviolet disinfection technology can be divided into two main types: low pressure and medium pressure. Low-pressure lamps have only monochromatic ultraviolet output (limited to a single wavelength of 254nm), while medium-pressure lamps have multi-color ultraviolet output (wavelength range between 185-400nm).
Advantages of UV disinfection
Compared with other disinfection methods, ultraviolet disinfection has many unparalleled advantages. Ultraviolet rays will not produce toxins or residues, nor will it change the chemical composition, taste, smell and pH of the liquid being disinfected. This feature is especially important in the fruit juice beverage industry. In chemical disinfection, the addition of chemicals to the production water will cause the taste and change the chemical properties of the product.
Ultraviolet treatment can be applied to raw water disinfection, or as a part of other water treatment processes, such as activated carbon filtration, reverse osmosis or low temperature sterilization. Because UV disinfection has no continuous disinfection ability, its best position in the treatment system is at the end link. In this way, the microbial pathogens introduced in all the previous links can be completely killed, so that the possibility of subsequent production pollution is minimized.
Application of ultraviolet disinfection in fruit juice beverage industry
Direct contact with water
Although general municipal water sources do not contain harmful or pathogenic microorganisms, this cannot be the basis. In addition, individual water sources such as natural spring water or groundwater may also be polluted. Any water used as an ingredient in juice or in direct contact with the product may become a source of pollution. Ultraviolet disinfection technology does not rely on chemical components to purify water, nor does it rely on heat disinfection, so that process water can be reused, which saves costs and improves production efficiency, and there is no risk of affecting product quality.
The syrup added to some fruit juices may be the main breeding ground for microorganisms. Although syrup with a high sugar content is not conducive to the growth of bacteria, the dormant spores may be activated after the syrup is diluted. Allowing the syrup and dilution water to undergo ultraviolet disinfection treatment before use can ensure that the dormant microbial tissues will not be activated again.
CIP (Clean Site) flushing water
The CIP final rinse water and disinfection method used to rinse impurities must meet microbiological safety standards. A fully automated UV disinfection system can be embedded in the CIP rinse water cycle to ensure that the final rinse water no longer introduces microorganisms and pathogens. The medium pressure lamp has high mechanical strength and will not be affected by sudden changes in CIP water temperature. For example, if the fluid temperature changes from 10oC to 80oC, the system will not be affected at all.