Is a white egg yolk safe to eat? (Yoke color facts)
In this brief guide, we will answer the question “Is a white egg yolk safe to eat?”, and will discuss why egg yolk can be white, what factors affect yolk color and if there are nutritional differences between them.
Is a white egg yolk safe to eat?
Yes, white egg yolk is safe to eat. While consumers often associate a well-colored egg yolk, typically golden yellow to orange, with healthiness and quality, and may perceive pale or non-uniform colored egg yolks as inferior products from unhealthy hens, this is not necessarily the case.
The color of an egg yolk is more a matter of consumer preference than an indicator of egg quality. Yolk color is one of the most easily controlled factors that affect the commercial quality of eggs. Across regions, some preferences and standards shape consumer choices.
For instance, in Europe, deeply colored yolks are preferred, whereas lighter hues are favored in the United States when it comes to table eggs. However, this preference is not universally shared as the baking industry specifically demands more intensely pigmented yolks.
What factors affect the color of egg yolk?
The color of a yolk is mainly influenced by a hen’s diet. By adjusting what the hen eats, it becomes possible to change the yolk’s color. The pigments responsible for yolk color come from their food, specifically carotenoids and chlorophyll. Carotenoids like carotene and xanthophyll create deep yellow yolks, while chlorophyll leads to darker orange-red yolks.
In the past, people believed that yolk color was determined by a particular hen breed. However, it is now widely accepted that there is no connection between yolk color and any specific breed of hen. (3)
How do foodstuffs affect the color of egg yolk?
Various food items lead to distinct yolk colors: rice, white oats, barley, wheat, and their by-products, along with meat, milk, and fish meal, typically produce pale yellow or nearly white yolks, yellow maize and green foods result in deep yellow yolks.
Young green foods rich in chlorophyll tend to yield dark orange-red yolks, cabbage gives rise to a brighter orange-red hue, and beetroot contributes to a dark yellow yolk color. Conversely, linseed imparts a greenish tinge to the yolks. (3)
What is the nutritional profile of egg yolk?
Egg yolks contain approximately 16% protein, 32% lipids, and 50% water. One-third of these lipids are phospholipids, with phosphatidylcholine being the dominant type, comprising approximately 80% of them. A medium-sized boiled egg weighing about 50 grams provides 78 calories. It contains 6.29 grams of protein, 0.56 grams of carbohydrates, and 5.3 grams of total fat.
Out of the total fat content, roughly 1.6 grams are saturated fats, while monounsaturated fats make up around 2 grams and polyunsaturated fats contribute to approximately 0.7 grams with approximately 186 milligrams of cholesterol Eggs are a rich source of micronutrients, encompassing vital minerals like calcium, iron, magnesium, phosphorus, potassium, sodium, and zinc.
Additionally, they provide an array of essential vitamins including thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, vitamin A, vitamin E, vitamin D, and vitamin K. Eggs provide a wealth of essential proteins, fats, vitamins, minerals, and bioactive compounds.
These components’ specific composition and quantity can vary depending on factors such as the egg’s strain, the hen’s age, diet, and environmental conditions. (4)
Why is organic egg yolk usually paler?
Egg yolks from organically raised hens appear lighter in color compared to those from conventional farming. This color difference is attributed to the presence of carotenoids in the hen diet.
Conventional hen diets often incorporate sources of carotenoids like corn gluten, alfalfa, saponified extracts from marigold flower, or paprika fruit, or even synthetic carotenoids such as astaxanthin or canthaxanthin to enhance the yolk color. These synthetic pigments can be utilized in conventional egg production to control and maintain yolk color at a consistent level.
However, in organic egg production, these additives are prohibited and hens in free-range and organic systems, with access to vegetation or provided plant-based forage, have ample access to carotenoids, especially when compared to hens in conventional systems, although this availability might decrease during winter making the yolk even more pale. (1, 5)
Is there a nutritional difference between yoke colors?
There likely isn’t a significant link between yolk color and its nutritional value, apart from the fact that higher carotene deposition leads to increased Vitamin A activity in the yolk. (3)
In this brief guide, we answered the question “Is a white egg yolk safe to eat?”, and discussed why egg yolk can be white, what factors affect yolk color and if there are nutritional differences between them.
Was this helpful?
SÜNDER, Angela et al. Egg yolk color in organic production as affected by feeding–Consequences for farmers and consumers. Food Chemistry, v. 382, p. 131854, 2022.
TITUS, Harry W.; FRITZ, James C.; KAUFFMAN, W. R. Some observations on egg-yolk color. Poultry Science, v. 17, n. 1, p. 38-45, 1938.
FRENCH, M. H. Quality in Egg Yolks. The East African Agricultural Journal, v. 4, n. 2, p. 102-104, 1938.
KUANG, Heqian et al. The impact of egg nutrient composition and its consumption on cholesterol homeostasis. Cholesterol, v. 2018, 2018.
HAMMEISHØJ, M. Organic and free-range egg production. In: Improving the Safety and Quality of Eggs and Egg products. Woodhead Publishing, 2011. p. 463-486.