PS8-13. Evaluating the Effects of Natural Preservatives on the Quality Characteristics and Shelf Life of Commercially Available Table Eggs.

Abstract

Natural preservatives are explored as coating materials for food preservation due to their biodegradability, antimicrobial properties, and alignment with consumer preferences for safe products. Eggs are perishable products that deteriorate rapidly if they are not handled and stored properly, and the longer the storage time, the greater the egg quality deteriorates, especially at room temperature. However, there is insufficient knowledge about the effectiveness of natural preservatives and coatings in prolonging the shelf life and quality attributes of eggs. A total of 180 fresh, non-fertile eggs of uniform age and flock origin were obtained from commercial stores based on the sell-by date indicated on the packaging. Eggs were randomly assigned to six treatments (n = 30 eggs per treatment): uncoated eggs (control), eggs coated with vegetable oil, or eggs coated with vegetable oil combined with natural preservatives (ginger, lime, moringa, or turmeric). Eggs were stored at room temperature (24 ± 2 °C, 50% relative humidity) and analyzed weekly at 0, 7, 14, 21, and 28 days for external and internal quality parameters. Data were analyzed using analysis of variance (ANOVA) with PROC GLM in SAS, considering each egg as an experimental unit. Significant differences (P < 0.05) were determined using Tukey’s Honestly Significant Difference (HSD) test. Fresh eggs (day 0) showed no differences in albumen and yolk indices across treatments. Egg weight loss was highest in uncoated eggs at all storage intervals (7, 14, 21, and 28 days) and lowest in lime-coated eggs (P < 0.05). Similarly, albumen pH was highest in uncoated eggs throughout storage, while significantly lower values were observed in coated groups, particularly in lime-treated eggs. At day 7, ginger coating reduced albumen width expansion compared to uncoated eggs. This effect became more pronounced by day 21 in turmeric-, moringa-, and ginger-coated eggs, and by day 28, all coated eggs exhibited reduced albumen spread relative to uncoated eggs. At day 14, turmeric-coated eggs showed increased yolk weight and yolk percentage, while lime coating significantly reduced both albumen and yolk pH compared to other treatments (P < 0.05). At day 21, moringa-coated eggs had higher yolk height and yolk index compared to vegetable oil-only and uncoated eggs. By day 28, several egg quality parameters had markedly deteriorated in uncoated eggs relative to herb-coated groups. Overall, herb-infused edible oil coatings effectively preserved egg quality compared to uncoated eggs, with lime-based coatings showing the greatest protective effect against quality deterioration during storage. Plant-based oils and herbal additives are edible, safe, cost-effective, and readily available, making them promising natural preservatives for extending the shelf life of table eggs, particularly in regions with limited access to refrigeration.