Eggs From Production To Table

As one of the most common and nutritious foods in human diet, eggs run through the food culture of all parts of the world. From a professional perspective, we comprehensively analyze the production process, quality identification, scientific storage, nutritional value and differences in eating eggs in China and abroad to help consumers better understand this daily ingredient.

1. Egg production process

The birth of a high-quality egg begins with a healthy hen. Modern laying hen farming usually adopts scientific management. Hens start laying eggs at 18-20 weeks of age, and the peak egg-laying period can last until about 80 weeks of age. The egg formation process takes about 24-26 hours: first the yolk is formed in the ovary, then enters the oviduct to add egg white, and finally the eggshell is formed and colored in the uterus. The production of high-quality eggs requires strict control of feed nutrition (protein, calcium, vitamins, etc.), drinking water quality, light time (14-16 hours/day) and breeding environment hygiene.

2. Egg quality identification method

2.1 Appearance inspection: The eggshell of fresh eggs is rough and shiny, while the surface of old eggs is smooth; the eggshell should be free of cracks and dirt. Brown eggs and white eggs are only different in species, and there is no significant difference in nutritional value.

2.2 Light transmission test: In a dark room, when irradiated with strong light, the air chamber of fresh eggs is small (less than 5mm), the outline of the yolk is blurred, and the egg white is clear; the air chamber of old eggs is enlarged, and blood or foreign matter may appear.

2.3 Water floating test: Put the egg in 10% salt water, the fresh egg will lie on the bottom; the slightly old egg will stand upright; the egg floating on the surface may have deteriorated.

2.4 Shell breaking observation: After the fresh egg is opened, the yolk is full and convex, and the egg white is clearly divided (thick egg white and thin egg white); the yolk of inferior eggs is flat and easy to disperse, and the egg white is thin and turbid.

3. Scientific storage method of eggs

The correct storage method directly affects the quality and safety of eggs:

3.1 Temperature control: The ideal storage temperature is below 4℃, and refrigeration can extend the shelf life to 4-5 weeks. Avoid drastic temperature changes that cause "sweating" and breed bacteria.

3.2 Placement: Store with the pointed end facing down and the yolk in the middle. Avoid placing with foods with strong odors, as the eggshell is porous and easily absorbs odors.

3.3 Cleaning: Do not wash the eggshell with water, which will destroy the natural protective film. If cleaning is required, wipe it with a dry cloth and wash it thoroughly before eating.

3.4 Special attention: Cracked eggs should be eaten immediately; cooked eggs should not be refrigerated for more than 1 week; separated egg whites and yolks can be frozen for several months.

4. Analysis of the nutritional value of eggs

4.1 Eggs are known as "natural nutrition banks". A large egg (about 50g) usually contains:

- 6-7g of high-quality protein (including all essential amino acids)

- 5g of healthy fat (including 1.5g of saturated fat)

- Vitamins A, B2, B12, D, E and other vitamins

- Minerals such as iron, phosphorus, selenium, zinc, etc.

- Choline (promotes brain development) about 147mg

- Calories about 70-80kcal

4.2 The lecithin in the egg yolk helps reduce cholesterol absorption, and recent studies have clarified that moderate consumption (1-2 per day) will not significantly affect blood cholesterol levels. Different breeding methods (such as organic, selenium-rich, omega-3 fortified, etc.) will produce certain differences in nutritional content.

5. Comparison of egg eating culture in China and foreign countries

Based on dietary traditions and cooking habits, various ways of eating eggs have been developed around the world:

5.1 Common ways of eating eggs in China:

- Boiled eggs (tea eggs, braised eggs)

- Fried eggs (poached eggs, sunny-side-up eggs)

- Steamed eggs (steamed eggs with minced meat, steamed eggs with clams)

- Scrambled eggs (scrambled eggs with tomatoes, scrambled eggs with chives)

- Special processing (pickled eggs, salted eggs, fermented eggs)

5.2 Common ways of eating eggs in the West:

- Breakfast eggs (poached eggs, scrambled eggs, omelets)

- Baking applications (cakes, bread, puddings)

- Salad ingredients (boiled egg slices)

- Sauce bases (mayonnaise, hollandaise sauce)

- Wine pairing (egg beer, eggnog)

5.3 Japan has raw egg rice and hot spring eggs; Southeast Asia often uses omelets with rice; the Middle East has special practices such as egg stew. Different cultures also have different preferences for egg doneness. Easterners prefer fully cooked eggs, while some parts of the West accept half-cooked eggs.

As an economical and efficient source of nutrition, scientific knowledge and rational consumption of eggs are essential for a healthy diet. Consumers should pay attention to the freshness of eggs, store them correctly, and try a variety of cooking methods to obtain the best nutrition and taste. The poultry industry will also continue to optimize production processes to provide the market with safer and more nutritious egg options.