Formulation and Application of Cinnamon Oil-Chitosan Emulsion Coating to Increase the Internal Quality and Shelf-Life of Shelled Eggs

Abstract

As time passes, eggs' internal quality deteriorates due to evaporation of carbon dioxide and moisture through the eggshell pores. To increase the internal quality and shelf-life of eggs, cinnamon oil (CO)–chitosan (CH) emulsions with ratios of 3:97, 6:94, 9:91, 12:88 were prepared. The coated eggs were then evaluated throughout 5 and 9 weeks of storage at 25 ± 2C and 4C, respectively. Test results revealed that the noncoated eggs' grade declined from AA to C after 4 weeks of storage. CO : CH 9:91 and 12:88 coated eggs' grade was, however, turned to B after 5 weeks of storage at 25 ± 2C. CO : CH 9:91 and 12: 88 emulsions coating significantly (P < 0.05) retarded the yolk index and Haugh unit decline rate and the increase of weight loss percentage, pH value and air cell height of eggs. This study demonstrated that CO:CH coatings with ratios of 9:91 and 12:88 could preserve the internal quality of eggs and prolong their shelf-life compared to the other treatments. Practical Application Coating the shell and covering its pores can preserve the internal quality and increase the shelf-life of refrigerated eggs. Coating eggshells is also being used instead of refrigeration in some developing countries and in farmers' markets. The results of this study revealed the effectiveness of even small amounts of the combined cinnamon oil and chitosan emulsion coating in decreasing the weight loss rate, prolonging the shelf life and maintaining the internal quality of chicken eggs.