QUALITY OF CONVENTIONAL AND FREE-RANGE EGGS DURING STORAGE

The objective of the study was to evaluate the quality of eggs from laying hens housed in the conventional cage system and a free-range system, submitted to 42 days of storage, and coated or not with mineral oil. For the experiment, 156 eggs from each production system were randomly assigned one of the to two treatments (with or without mineral oil), using a completely randomized design. Eggs produced in the conventional cage system had higher Haugh unit, while free-range eggs had higher values of egg weight, albumen pH, and yolk color. Egg quality deteriorated over storage time, regardless of the production system or eggshell treatment. There was an increase in weight loss and albumen pH, and a reduction in the yolk index as the storage period increased, with more pronounced responses for eggs that did not receive the mineral oil treatment in the eggshell (P < 0.001). In conclusion, eggs produced in different housing systems show differences in internal quality, with favorable results for eggs produced in the conventional cage system. Eggs lose quality during storage and the use of mineral oil is an effective alternative for increasing the shelf-life of eggs, regardless of the production system.