Poultry Science (Dec 2020)
Survey of egg quality in commercially available table eggs
Abstract
Increased demand in consumer choice has resulted in a wide variety of egg selection available in the retail market. Specialty and designer chicken eggs represent a portion of the table egg market that is increasing in size. Egg quality is known to be of great importance in all eggs as it relates to food safety, consumer preferences, and product value. In this study, egg quality characteristics were analyzed using a one-way ANOVA to evaluate 2 commercially available conventional egg brands (A and B) and 4 commercially available designer egg brands (C–F). Three hundred nine eggs were evaluated for shell and content weight, dimensional measurements, and breakage force. Calculations were completed to determine %yolk and albumen, yolk index, and Haugh units (HU), followed by an accelerated lipid oxidation study. No significant variation exists in breakage force. Brands A–E meet AA grade standard at a score of 72 HU or above, while brand F, a pasture-raised brand, meets the A grade standard, falling between 60 and 71 HU. Brand F has the highest yolk fan color value (10.41 ± 0.193, P < 0.001) and the lowest yolk index (0.523 ± 0.013, P < 0.05). In addition, brand F has the lowest albumen height (P < 0.001). As albumen height is an indication of freshness, and as all eggs were of equivalent age, it is possible that brand F exhibits overall lower quality than other brands. The conventionally raised white eggs of A experienced the greatest increase in % free fatty acids, which would likely result in off-flavors from hydrolytic rancidity. The organic cage-free D eggs have a significantly greater peroxide value (17.3 ± 2.9, P < 0.001), relative to all other brands, and is over the 10 mEg/kg threshold, which would be considered an unsuitable product for consumption. Ultimately, the measures of egg quality used in this study are essential for evaluating the delivery of the specialty market to the consumer and may indicate that improved measures of quality are needed to truly differentiate between the different egg types and their quality.
