The present study evaluated the physicochemical and sensory traits of marketed table eggs, deriving from different farming methods (cage, barn, and organic) and sampled in different marketing periods (June, July, September, October). A total of n=540 eggs (n=45 eggs/farming method/sampling period) of “medium” weight-grading were purchased and subjected to physical measurements (shell, yolk, and albumen physical traits), chemical evaluations (proximate composition, cholesterol content and fatty acid profile of the edible portion) and to a descriptive sensory analysis. Results highlighted that eggs physical traits often differed among the considered farming methods: organic eggs had the lowest albumen pH (P < 0.001) and the highest albumen proportion (P = 0.004), whereas barn and cage eggs had the highest yolk proportion (P = 0.026). Barn eggs had the heaviest shell proportion (P = 0.011), which did not however imply a higher resistance to penetration and compression tests. As expected, egg colour differed according to the farming method with cage eggs displaying the highest overall yolk colour intensity (a*, b* and yolk colour FAN; P < 0.001), followed by barn and organic eggs. The egg marketing period demonstrated to be a relevant factor in determining egg physical attributes too. Surprisingly, organic eggs showed constant albumen, yolk and shell physical characteristics, and yolk colour traits, whereas barn and cage eggs displayed a certain variability in these terms. Cage eggs showed the highest protein (P = 0.001) and barn eggs the highest lipid (P = 0.003) contents, whereas cholesterol content was only affected by the marketing period in all three farming methods. Organic eggs were the richest in moisture (P = 0.003), in polyunsaturated fatty acids (FA) of both n-6 (P = 0.011) and n-3 series (P < 0.001), whereas cage ones had the highest saturated (P = 0.030) and monounsaturated (P = 0.018) FA. Among the considered sensory traits, farming method only affected the yolk colour intensity, which was the lowest in organic eggs and, for cage and barn eggs, it decreased along the marketing period. Results of the present research indicated that the overall quality of marketed table eggs effectively differs according to the farming method and to the marketing period time which is a relevant information, yet poorly investigated, from the consumer's point of view. Organic eggs were the most distinguishable, especially in terms of yolk colour and nutritional composition.

本研究评估了市面食用鸡蛋的理化特性，这些鸡蛋来自不同的耕作方法（网箱，谷仓和有机食品），并在不同的市场销售时期（6月，7月，9月，10月）进行了抽样。总共购买了“中等”体重分级的n = 540个鸡蛋（n = 45个鸡蛋/种田方法/采样时间），并进行了物理测量（蛋壳，蛋黄和蛋清的物理特性），化学评估（近似组成，胆固醇含量和可食用部分的脂肪酸谱），并进行描述性的感官分析。结果表明，在所考虑的耕作方法中，鸡蛋的物理特性通常有所不同：有机鸡蛋的最低蛋白pH值（P <0.001）和最高蛋白比例（P = 0.004），而谷仓和网箱蛋的蛋黄比例最高（P  = 0.026）。谷仓蛋的壳比重最大（P  = 0.011），但这并不意味着对渗透和压缩测试的抵抗力更高。正如预期的那样，鸡蛋的颜色根据耕种方法的不同而不同，网箱鸡蛋显示出最高的蛋黄色强度（a *，b *和蛋黄色FAN; P<0.001），然后是谷仓和有机鸡蛋。鸡蛋销售期也被证明是决定鸡蛋物理特性的一个相关因素。出乎意料的是，有机鸡蛋显示出恒定的蛋白，蛋黄和蛋壳的物理特性，以及蛋黄的颜色特征，而谷仓和网箱鸡蛋在这些方面表现出一定的变异性。笼养鸡蛋的蛋白质 含量最高（P  = 0.001），谷仓鸡蛋的脂质含量最高（P = 0.003），而胆固醇含量仅受三种耕种方式的销售期影响。有机鸡蛋的水分 含量最高（P = 0.003），n-6系列（P  = 0.011）和n-3系列的多不饱和脂肪酸（FA）含量最高（P<0.001），而笼式笼具有最高的饱和（P  = 0.030）和单不饱和（P  = 0.018）FA。在考虑的感官特征中，耕作方法仅影响蛋黄颜色强度，这在有机蛋中最低，而对于网箱蛋和谷仓蛋，蛋黄颜色强度随销售期而下降。目前的研究结果表明，根据食用方式和销售周期，出售的食用鸡蛋的整体质量实际上有所不同，这是一个相关信息，但从消费者的角度来看，调查还很少。有机鸡蛋是最明显的，特别是在蛋黄颜色和营养成分方面。