Evaluation of the use of propolis and sodium hypochlorite as methods to control contamination of free-range eggs

In recent years, the production of free-range eggs has increased due to growing consumer interest in animal welfare. However, this production method introduces new sanitary challenges due to free-range housing, which can increase the microbiological risk. It is therefore essential to implement proper egg sanitization practices to avoid contamination by harmful microorganisms. The use of propolis and sodium hypochlorite can be effective in improving the bacteriological quality of eggs, due to their antimicrobial properties. The aim of this study was to evaluate the effectiveness of 1% sodium hypochlorite and 30% propolis extract as methods of controlling egg contamination on a free-range farm located in southern Brazil. Eighteen eggs were collected and divided into three groups: six eggs were sprayed with 30% propolis, six were sprayed with 1% sodium hypochlorite and six eggs were used as controls, without spraying. For shell analysis, 6 eggs from each group were rinsed in 0.1% buffered peptone water. For the contents, two yolks from each group were used, adding peptone water in a ratio of 1:9. Mesophilic aerobes were counted using the plate count agar (PCA) method and colonies were counted after 48 hours of incubation (36ºC). On eggshells, the results were as follows: propolis: 0.6 log UFC/mL, sodium hypochlorite: 1.3 log UFC/mL, control: 3.26 log UFC/mL. In the egg contents, the propolis and sodium hypochlorite treatments had 0 log CFU/g, while the control group had 4.78 log CFU/g. It can be concluded that both methods were able to reduce the microbiological load of the eggshell and egg contents, with propolis being the most effective in this process.