Eggs are like the ultimate wardrobe staple—they can take center stage or play supporting roles in dishes, packed with nutrients and a staple in nearly every household.
Yet despite their simplicity, opinions on how to prepare eggs vary widely. Some claim raw eggs are more nutritious than boiled ones, arguing that cooking destroys their nutritional value. But what's the truth?
I. Are Raw Eggs Poached in Hot Water More Nutritious?
Many people do enjoy "boiling water over raw eggs," but what they may not realize is that a danger lurks quietly nearby: Salmonella in eggs.
Statistics reveal that over 100 million people worldwide are infected with Salmonella annually. Mild cases may present with vomiting and diarrhea, while severe infections can lead to typhoid symptoms. Tragically, many (155,000) even die from it.
In China, over 90% of infections originate from eggs, meat, and dairy products. Elderly individuals, infants, and those with weakened immune systems are particularly vulnerable.
What troubles many is that, like "indestructible cockroaches," it thrives in extremely low-maintenance environments, surviving between 5°C and 46°C. Fortunately, it has a fatal flaw: intolerance to high temperatures. Exposure to over 100°C instantly kills it.
However, at temperatures around 50-60°C, it may take 30-40 minutes to eliminate the bacteria.
Therefore, we can conclude that pouring boiling water over eggs carries a risk of infection. Although the boiling water exceeds the bacteria's tolerance range, the temperature rapidly drops when it contacts the cold egg and cup, preventing complete elimination of the bacteria. Consuming such eggs poses a risk of infection.
Additionally, some believe raw eggs are more nutritious because they haven't been damaged by high temperatures, particularly regarding protein denaturation. However, it's important to know that the protein in eggs is only easily digested and absorbed after being heated and denatured during cooking, achieving 100% absorption. In contrast, raw consumption yields only 30% to 50% absorption.
Regarding nutrient loss, while some fat-soluble vitamins (like vitamin E) are indeed destroyed by high heat, water-soluble vitamins (such as B vitamins) are actually protected. Thus, there's no need to worry about nutritional deficiencies in boiled eggs.
II. Which method is more nutritious: boiled eggs, fried eggs, or scrambled eggs?
Any cooking method should consider two aspects: first, whether it destroys nutrients in the food; second, whether it produces new harmful substances.
First, prioritize fully cooked eggs. The protein bioavailability of cooked eggs far exceeds that of raw eggs. In terms of nutrient absorption and digestibility: boiled eggs are 100%, scrambled eggs are 97%, lightly fried eggs are 98%, egg drop soup (boiled water with eggs) is 92.5%, while raw eggs range from 30% to 50%.
Second, frying, scrambling, and boiling all cause some nutrient loss. Moreover, frying and scrambling often involve substantial amounts of oil and salt, and prolonged high-temperature cooking may generate harmful substances.
Therefore, overall, boiling is the most ideal method. However, it's important to note: eggs should not be boiled for too long—generally 8-10 minutes is sufficient.
Overcooking causes the yolk surface to turn grayish-green (due to ferrous ions in the yolk reacting with sulfur ions in the white to form ferrous sulfide), a compound poorly absorbed by the body that reduces nutritional value.
For children and the elderly, steamed egg custard or egg drop soup is more suitable, as these methods break down proteins into easily digestible forms.
Additionally, many people make mistakes when cleaning and storing eggs, so let's continue.
III. Should raw eggs with chicken droppings be washed with water?
It's common for purchased eggs to have traces of chicken droppings. While many people instinctively wash them off with water, this practice is actually not recommended.
Although eggs appear intact on the surface, they actually have numerous tiny pores invisible to the naked eye. These pores are sealed by a thin membrane. Washing the eggs damages this membrane, making them more susceptible to bacterial contamination.
Therefore, it's crucial to note: if you really can't stand it, gently wipe the surface clean with a cloth before refrigerating.
Egg Storage Guidelines:
Proper storage requires specific care. Eggs should be stored separately, with the smaller end down and larger end up. This positions the yolk toward the top, making it harder for microorganisms to invade. It also keeps the yolk close to the air cell, preventing direct contact with the shell and minimizing nutrient loss.
Avoid storing eggs near strongly scented foods like onions, ginger, or garlic, as odors can transfer and cause eggs to spoil.
To enjoy fresh eggs, avoid buying too many at once. If you do purchase a larger quantity, lightly coat the eggshells with cooking oil. This helps block airborne bacteria and prevents moisture loss, extending the eggs' shelf life.
Eggs are a staple in our daily diet—delicious, versatile, and nutrient-rich. However, consuming them requires some know-how. Mastering these techniques ensures every egg you eat is truly worth savoring!
Interaction: How do you prefer to eat your eggs?
References
[1] "Is Eating Raw Eggs Really Good for You?"Chongqing Evening News. 2020-06-02
[2] "Beware of the Invisible Threat: Salmonella". Beijing Youth Daily. 2018-01-24