Application of ozone in cold storage

 

Ozone in the storage of vegetables and fruits, in addition to kill or inhibit the growth of mold, prevent decay, but also prevent aging and other fresh. The mechanism is that ozone can oxidize and decompose the ripening agent - ethylene gas C2H4. Ethylene intermediates also have inhibitory effects on fungi and other microorganisms. Ozone can play a role in sterilization, mildew prevention and rapid decomposition of ethylene to slow down the metabolism, delay the ripening, aging and decay, together with packaging, refrigeration, air conditioning and other means to improve the fresh-keeping effect.

 

1.ozone preservation technology

 

Ozone gas was used in refrigerated storage to preserve fruits and vegetables. Ozone has been used in cold storage for nearly 100 years worldwide. The application of ozone in cold storage started late in China. With the improvement of the manufacturing technology of ozone generator, ozone is more and more widely used in cold storage.

 

According to the physical and chemical properties of ozone, it is effective to use it for preservation. The test shows that the ozone generator should be installed on the wall 2 meters away from the floor of the storage room, and it should be switched on for 1-2 hours every day. The refrigerator should be closed as far as possible to maintain and improve the ozone concentration, and the indoor humidity should be controlled at about 95%. In the case of higher humidity, sterilization and preservation effect can be greatly improved.

 

2. ozone in the refrigerator sterilization, fresh, mildew - proof three stages.

 

Empty storage sterilization, disinfection, storage sterilization, preservation and daily mildew proof refrigerator design, the purpose is to reduce mold, yeast caused by the rot. The ozone generator is turned on for 24 hours and turned over for disinfection. The ozone concentration is maintained at about 2-10ppm. It stops for 1-2 days before storage to seal the warehouse.

 

It is difficult to establish the ozone concentration because the cooling fan has been running. At this time, the ozone generator should be placed at the farthest end of the reservoir from the cooling fan. At this time the ozone generated by the air cooler driven by the air flow and fruit and vegetable surface contact, play a part of the role of sterilization. Ozone can be opened all the time before bagging, due to large storage capacity, air flow, will not reach 2.5 PPM harm concentration.

 

Daily mildew control for the air storage and gas account to be adjusted to supplement the air at the same time into the ozone, at this time should choose a pressure, ozone concentration of moderate ozone source. The packaging of fruits and vegetables should be conducive to contact and diffusion, the holes in the side of the carton should be opened, not piled. Ozone should be fed into the air conditioning warehouse and air conditioning account by pipes. Ozone packaged in natural air conditioning plastic bag with silicon window can penetrate into the cold storage board. Ozone can be applied before and after air change in plastic bag. The NPF, NP and NPS series generators developed by Shandong Lvbang Company meet this requirement and can input ozone through pipelines. The small package can be opened through the silicon window or open the bag before and after air purification ozone sterilization air, odor removal.

 

Practical application shows that ozone can strongly inhibit the expansion of the garlic moss bud decay, if there is mildew, it can be directly exposed to ozone sterilization to inhibit its expansion. Fruits such as apples, pears and grapes have good ozone effect, and the intermittent application concentration does not exceed 2.0 PPM without any harm. Ozone mildew-proof fresh vegetables and fruits remain fresh for a period of time after they are shipped out of storage.