Air Disinfection in Food Processing Workshops
In food processing enterprises, problems such as excessive total colony counts and mold in food due to air pollution are no longer unfamiliar.
Faced with the country's increasingly strict control over food, more and more food factories have gradually begun to pay attention to the
problem of air quality in the workshop.
Only by strictly controlling the disinfection of the air in the food processing workshop can the content of microorganisms in the air in the
workshop be effectively controlled to prevent product contamination and mold.
- 1. Physical disinfection
- 2. Chemical disinfection
Ultraviolet disinfection
Common form: Evenly distribute ultraviolet sterilization lamps on the ceiling of the workshop, and use the ultraviolet radiation generated by
them to disinfect and sterilize the surface of objects and the air.
Advantages:
Simple operation, low price, convenient management, flexible and mobile, individual rooms can be disinfected and sterilized at any time
according to production needs, without adding or producing any toxic and harmful substances.
Disadvantages:
- 1. The intensity of ultraviolet rays emitted by ultraviolet lamps decreases with the increase of use time, so the disinfection and sterilization ability continues to weaken.
- 2. Ultraviolet rays have weak penetration and are easily blocked by production equipment, resulting in dead corners and affecting the steril-ization effect.
- 3. Ultraviolet sterilization is greatly affected by relative humidity. When the relative humidity in the clean room is ≥60%, its sterilization effec-t is significantly weakened. When the relative humidity is ≥80%, it is not suitable for use.
- 4. Ultraviolet radiation energy is low and can only kill microorganisms directly irradiated. Therefore, the disinfected area must be fully expos-ed to ultraviolet rays.
- 5. The distance from the surface of the object irradiated by ultraviolet rays should not be ≥1.50m
- 6. It cannot be used when there are people at work
Air filtration
Air filtration is a method of removing dust and microorganisms from the air medium by physical retention.
In food manufacturing, especially the packaging process, a purified environment (clean room) is required for aseptic (purified) packaging. This
clean room purifies the filtered air and enters a specific environment. The food after heat sterilization enters the environment and is cooled and
packaged. The food packaging purification environment here is equivalent to the ultra-clean workbench in the laboratory, which can achieve
aseptic packaging.
Fumigation is the use of disinfectant gas or smoke to fumigate in a closed space to achieve the purpose of disinfection. This method can be used
to treat indoor air (polluted air) and can also be used to treat contaminated surfaces. Food production and operation sites should be fumigated
regularly to ensure the cleanliness of the production site and air.
The products used for fumigation are currently more (formaldehyde, potassium permanganate, peracetic acid, chlorine dioxide). Food companies
are reminded not to use formaldehyde and potassium permanganate for fumigation.
Why is it not recommended for food companies to use formaldehyde fumigation to disinfect workshop air?
1. The disinfection and sterilization time is long, which affects production. For example, formaldehyde fumigation: disinfection time is 12h,
standing for 4h, exhaust for 8h, and disinfection takes at least 24h. Disinfection requires 2~5 days of suspension.
2. In order to eliminate irritating odors, the ventilation system is turned on for a long time after disinfection and sterilization, and the
non-production operation time is too long, which wastes a lot of energy.
3. An exhaust system or facility needs to be set up.
4. It is easy to produce secondary pollution. For example, formaldehyde fumigation will produce polyformaldehyde polymer (white powder),
which will be attached to the surface of the maintenance structure and equipment pipes in the clean room. Within a few days after disinfection,
the number of suspended ions will increase, and the formaldehyde polymer will gradually depolymerize into formaldehyde, which is very harmful
to production operators.
5. The disinfection interval is long. Since each chemical reagent fumigation disinfection and sterilization time takes at least 24 hours and cannot
be carried out every day, most manufacturers currently use a large disinfection once a month, while the microbial contamination sources - people,
objects, materials, outdoor fresh air, etc., have to enter and exit the workshop every day, and the microorganisms brought in cannot be killed in
time, and the phenomenon of microorganisms increasing over time will occur.
6. There is a strong irritating odor. After disinfection and sterilization, it stays in the indoor environment for a long time. It takes a long time to
remove the residual odor, which is harmful to the health of production operators and has a carcinogenic effect.
Ozone disinfection:
Looking at the mechanism and process of ozone disinfection and sterilization, the following characteristics can be summarized:
1. High-efficiency ozone's chemical properties, the instability of the three oxygen atoms, and the easy decomposition characteristics determine its
strong oxidation and sterilization capabilities, and its killing rate for microorganisms such as viruses and bacteria is extremely high. Therefore,
ozone is a highly efficient sterilizer.
2. Environmental protection (or cleanliness) The half-life of ozone is about 20 minutes. After the ozone is oxidized and sterilized, the excess
oxygen atoms will combine into oxygen molecules after 30 to 40 minutes, without producing any toxic residues, and there is no secondary
pollution problem after sterilization; at the same time, it increases the oxygen content of indoor air, and also has a strong function of removing
mold, waking up, smelling and other organic odors. It has a significant effect on the mildew and insect prevention of Chinese medicinal materials
and other raw and auxiliary materials, and improves the quality of clean indoor air environment, so it is called a clean disinfectant.
3. Broad-spectrum ozone has a strong oxidative destructive effect on the internal structure of microorganisms such as bacteria and viruses when
its concentration in the air reaches 2 to 15 ppm. Therefore, it and chemical reagents such as formaldehyde, ethylene oxide, and peracetic acid
are all broad-spectrum sterilizers.
4. Thoroughness Since ozone is a broad-spectrum sterilizer, it diffuses evenly in a relatively closed environment at a certain concentration. It only
takes 30 to 60 minutes to kill bacteria in the clean room, overcoming the shortcomings of ultraviolet sterilization with many dead corners, and
achieving the purpose of all-round disinfection and sterilization.
5. Economical Ozone is introduced into the air conditioning system for circulation disinfection, which has the effect of preventing mildew and
blocking on air purification equipment, filtration system, and medium filtration materials. It can reduce the aerosol particles suspended in the air,
improve the cleanliness of the air, extend the service life of the purification equipment, and reduce the operating cost, which is impossible for
other methods. At the same time, because ozone disinfection does not cause secondary pollution problems, it is not necessary to set up exhaust
measures for secondary cleaning, which reduces the initial investment of air conditioning facilities, does not need to set up duty fans, and saves
operating costs.
6. Simple operation When disinfecting, ozone is directly introduced into the clean room or air conditioning system. According to the characteristics
of the clean room, the disinfection time is determined, the timer is set, and the machine automatically shuts down after the disinfection is
completed. The operation and use are particularly simple.
7. Short running time When using ozone disinfection, the disinfection time is generally 30 to 60 minutes. After disinfection, the excess oxygen
atoms will combine into oxygen molecules after 30 minutes. It only takes 60 to 90 minutes to complete a disinfection, which is both time-saving
and safe.
Chlorine dioxide disinfection
Advantages:
- The fourth generation of peroxide disinfectants containing chlorine rather than chlorine preparations; exists in molecular form, oxidative sterilization, and does not generate organic halides such as chloroform;No drug resistance;
- Killing range is wide, and has good inhibition and killing effects on bacteria, fungi, viruses, spores, AIDS, hepatitis B, etc.;
- Not affected by factors such as temperature, humidity, and pH value;
- A product can be diluted to different concentrations according to different objects;
- Can be sprayed, soaked, wiped, fumigated, sprayed, etc.;
- Can be used for personnel, equipment, utensils, space environment, production water, etc. in food production;
- Its application scope is involved in relevant national standards such as GB5749, GB2760, GB26366, and GB20783;
- Under a certain concentration, the antibacterial ability is 1.9 times that of ozone;
- Multiple experiments have shown that 50ppm soaks and disinfects hands for 20-30s, and the killing rate can reach more than 90%
Disadvantages:
- It has a pungent smell similar to chlorine;
- There is an activation link.
Warm Tips
Food safety is a systematic project. It is not a certain disinfectant or a disinfection equipment that can completely guarantee food safety, but
requires a reasonable combination of various disinfection equipment.
There are many ways to disinfect the air in food production workshops, but each method has its scope of application and limitations of use. Only
when the food production workshop masters the use method and scope of application of each disinfection method, and combines the air
disinfection of the processing site with the strict implementation of scientific disinfection, can it produce hygienic and safe food, further protect the
health of consumers, and promote its own healthy development.
For more information about the air disinfection in the food factory, welcome to communicate with us !
