Code 1 Means Free-Range, Code 4 Means Crowded... Does the Egg Shell Code Indicate Nutritional Differences?

Egg Shell Codes 1 to 4: Lower Numbers Mean Better Rearing Conditions
Little Difference in Nutritional Content... Freshness Best Judged by Laying Date

Recently, eggs released by a celebrity have sparked controversy over high prices, drawing increased consumer attention to egg quality standards and rearing conditions. The product in question was sold at a price similar to that of free-range eggs (category 1), despite its egg shell code ending in '4' (conventional cage farming), which fueled the debate.

Image of eggs to aid article understanding. Pixabay

According to the Rural Development Administration, eggs distributed in South Korea are labeled with a 10-digit egg shell code, which includes a 4-digit laying date, a 5-digit unique farm number, and a 1-digit rearing environment code. Among these, the 'rearing environment code' (the last digit) is an important standard for consumers who value the production process and animal welfare. There are four codes: 1 (free-range), 2 (barn), 3 (improved cage), and 4 (conventional cage), with lower numbers indicating better rearing environments.

In particular, code 4 (conventional cage) means each chicken has only 0.05㎡ of space, which is smaller than an A4 sheet of paper. In contrast, codes 1 and 2 represent environments certified for animal welfare. However, the rearing environment is not directly related to the nutritional content of the eggs.

The Korea Poultry Association explains, "The rearing method only reflects differences in the chickens' activity and welfare levels; the egg shell code does not indicate nutritional superiority." On the other hand, rearing conditions have been shown to affect the chickens' stress levels and health. In fact, research has found that eggs from chickens raised in improved cages have stress hormone levels nearly twice as high as those from free-range chickens.

The government has begun revising regulations to improve rearing conditions, and eggs with code 4 on the shell are expected to disappear from the market starting in September 2027.

Freshness, Size, Functionality... Nutritional Differences Are 'Less Significant Than Expected'

The 'Haugh Unit (HU)', used as a standard for egg freshness, indicates that the higher the value, the fresher the egg. However, since most distributors manage freshness, industry experts say it is difficult to claim that any particular brand is exceptionally fresh. To select fresh eggs, checking the first four digits of the egg shell code for the laying date is the most reliable method, and it is best to consume eggs as soon as possible after purchase.

Experts also explain that egg size or functional labeling is more a matter of choice than a difference in nutritional content. Larger eggs contain more nutrients by volume, but the composition itself does not change. There is also little difference in nutrition between fertilized and unfertilized eggs.

The Science Institute stated, "There may be some differences in nutritional content, but aside from functional substances, there are no significant differences in the overall composition." Executive Director Kim also said, "If expensive feed ingredients are given to chickens, those nutrients can be present in the eggs. However, this only creates subtle differences and does not significantly affect the nutritional content."

Ultimately, the standard for what constitutes a 'good egg' may vary depending on which factors consumers prioritize. It is advisable to make individual judgments based on rearing environment, freshness, and size when choosing eggs.

This content was produced with the assistance of AI translation services.