DISINFECTION OF FRUIT AND VEGETABLES BY OZONE

The purpose of disinfection of fruits and vegetables is to protect them against the harmful effects of bacteria, protozoa and fungi. Disinfection cannot be bypassed, because the losses would be greater than the profits and production would become unprofitable. Despite the constant tightening of safety criteria, commonly used disinfection methods still leave much to be desired. The most preferred alternative to popular methods is ozonization.

Currently used methods of disinfection:

Chlorine compounds: chlorinated water, acid sodium chlorite, chlorine dioxide - cause the production of carcinogenic by-products, such as chloroform.

Peracetic acid - causes corrosion of elements made of brass, copper, bronze, steel and galvanized iron. A solution higher than 5% creates a risk of burns.

Hydrogen peroxide - its vapors can cause hair discoloration in employees.

Blanching - has fairly limited use due to adverse changes caused by heat in the case of leafy vegetables and soft fruit.

Gamma radiation - a dose that effectively eliminates microorganisms very often lowers the nutritional value of vegetables and fruits at the same time.

Ultraviolet radiation - causes, among others formation of free radicals, destruction of vitamins and dyes and adverse organoleptic changes.

As you can see, all the methods used have disadvantages. This means that producers are forced to use several methods at the same time (with various productions). This increases costs, causes nuisances and generates threats. Ozone treatment in this situation is the most beneficial alternative to the methods used, while providing the greatest benefits and eliminating unwanted side effects.

Disinfection by ozonation - FACTS

Blackberry tests - after 12 days of storage at 20 ° C, about 20% of blackberries deteriorate as a result of the growth of mold fungi. After the same period, no ozone damage or adverse changes were seen in the ozonated fruit batch.

Research on apples - the apple batch was stored for 3 months at 2 ° C, and then for 13 days at room temperature. Burns occurred on about 80% of the fruit. The same experiment was carried out in parallel on a batch of ozonated apples. Neither mold nor burns were found.

Research on strawberries - washing fresh strawberries with water containing an average of 2.7 ppm ozone reduces the total number of E. coli and coliform bacteria, and the total number of bacteria, yeast and mold growing on the plates. The effect was estimated on 95-98% of removed organisms.

Carrot tests - whole carrot roots were stored in an atmosphere containing 0.0; 7.5; 15.0; 30.0 and 60.0 μl ozone. The rate of carrot respiration, electrolyte leakage, and differences in color increased with increasing ozone concentration. Carrots were less intense in color compared to the control sample.

Broccoli tests - lower levels of ethylene were observed for broccoli treated with ozone.

Ozone disinfection - CONCLUSIONS:

• ozonation extends the shelf life of vegetables and fruits;
• ensures microbiological purity;
• leaves no harmful by-products;
• ensures greater employee safety and eliminates the need for chemicals;
• many sources agree that the efficiency of disinfection by means of ozonation is fifty times greater than those based on chlorine.

The ozonization disinfection method is widely seen as relatively expensive in the implementation process. However, in a perspective term it is a technology that generates savings in total production costs. It is also worth emphasizing that this is the technology of the future and it is in this direction that global trends will weigh in the coming decades, because ozonization is gaining more and more trust from both producers and consumers from year to year.