Eggs are a nutritious and versatile food that can be prepared in many different ways. One popular method is cooking eggs “over medium,” which leaves the whites fully cooked while the yolks remain runny. But are over medium eggs considered fully cooked from a food safety perspective? Let’s take a closer look at what cooking eggs to this doneness level means.
What does “over medium” mean?
When eggs are cooked over medium, the whites are fully set while the yolks are warmer and runnier in the middle. Technically, there is no single definition of over medium eggs, but they are generally characterized by:
- Firmed up egg whites that are completely opaque and set, with no translucent or runny parts
- Yolks that are partially cooked and thickened, but still liquid and runny in the center
The key is that while the whites are fully cooked through, the yolks are cooked to the point where they thicken but remain soft, jammy, and fluid on the inside.
Are the whites fully cooked?
Yes, when eggs are cooked over medium, the whites are always fully cooked and safe to eat. Egg whites coagulate and set at temperatures starting around 144°F to 149°F. As the proteins denature and bond together, the liquid egg white becomes completely firm and opaque.
With over medium eggs, the whites reach well above the minimum temperature needed to fully cook and solidify them. The whites should reach an internal temperature of at least 160°F to be considered safe and ready to eat.
Are the yolks fully cooked?
No, the yolks are not fully cooked or solidified when eggs are prepared over medium. The yolks coagulate and begin thickening at temperatures between 149°F and 158°F. However, they don’t fully set until reaching 160°F or hotter.
With over medium eggs, the goal is to heat the yolks so they thicken slightly and turn opaque around the outer edges, while keeping the inside undercooked and runny. This means they don’t reach the higher temperatures needed to fully cook through and solidify them.
Why are the yolks left runny?
There are a few reasons professional chefs and home cooks may intentionally undercook the yolks when preparing eggs over medium:
- Runny egg yolks provide a pleasing visual contrast to the firmer whites.
- The liquid yolk texture provides a luscious, rich mouthfeel when eaten.
- Heating only partially coagulates the proteins, leaving the yolk thickened but still creamy-textured.
- The inner uncooked yolk remains extremely hot while the firmer outer layer contains it neatly.
- Runny yolks allow for mopping up and dipping of toast, hash browns, etc.
The runny yolks in over medium eggs provide both visual appeal and desired texture/mouthfeel for many egg lovers.
Are runny egg yolks safe to eat?
Runny or undercooked egg yolks present higher risks of foodborne illness compared to fully cooked yolks. Potential food safety issues with runny yolks include:
- Bacterial growth – Salmonella and other bacteria can survive in raw or undercooked egg yolks.
- Biogenic amine toxicity – Undercooked yolks contain higher levels of amino acids that can convert to biogenic amines like tyramine.
- Allergen exposure – Runny yolks retain more intact egg proteins that provoke allergic reactions for sensitive individuals.
However, the risks are still relatively low for eggs from healthy chickens that have been properly handled and refrigerated:
- Salmonella penetration is low for uncracked, clean Grade A/AA eggs. Salmonella risk increases if shells are cracked/dirty.
- Tyramine toxicity mainly occurs after prolonged storage or inadequate refrigeration, allowing more amine conversion.
- Those with egg allergies must avoid all yolks, cooked or uncooked.
For most people, runny yolks pose minimal risks if eggs are very fresh and stored/handled properly. But those who are very young, elderly, pregnant, or immunocompromised may still want to avoid undercooked yolks whenever possible.
Can raw or runny yolks contain harmful bacteria?
Yes, raw or runny egg yolks can potentially harbor harmful bacteria like Salmonella. Here are some key facts about Salmonella and undercooked yolks:
- Salmonella is occasionally present inside perfectly normal looking shells, even with clean, uncracked Grade A eggs.
- The inner egg yolk could be contaminated with Salmonella from the hen’s infected ovaries prior to the shell forming around it.
- Salmonella starts dying rapidly at sustained temperatures above 160°F. Runny yolks may not reach high enough temps to destroy bacteria.
- Acidic yolks provide some protection against bacterial growth, but some Salmonella can survive pH as low as 4.2-4.6.
While Salmonella inside eggs is uncommon, the bacteria can survive if the yolk remains raw or undercooked. Proper food handling and cooking the yolks completely are necessary to kill any pathogens present.
Should you request fully cooked yolks?
Those most at risk for foodborne illness or who simply want to err on the side of caution can request eggs cooked fully through without runny yolks. Some options for fully cooked yolks include:
- Over hard – Yolks are fully cooked through until completely solidified and firm.
- Over well – Whites and yolks are fully cooked and firm with no runniness.
- Hard boiled – Boiling until both yolks and whites are fully set and solid.
Individuals who should consider always requesting fully cooked yolks without runniness include:
- Young children
- Pregnant women
- Older adults
- Those who are immunocompromised
- Anyone wanting to limit foodborne illness risks
Can you make over medium eggs safer to eat?
There are some methods that can reduce the risks of potential foodborne pathogens in over medium eggs with runny yolks:
- Use pasteurized shell eggs – Pasteurization kills Salmonella while maintaining raw properties.
- Don’t use eggs with cracked shells – Cracks can allow bacteria inside.
- Cook eggs thoroughly until whites are completely set.
- Use a food thermometer – Cook whites to at least 160°F and yolks to your desired doneness.
- Don’t allow eggs to pool together on the plate – Prevent cross contamination.
- Refrigerate promptly after cooking – Don’t leave eggs at room temperature.
Proper purchasing, storage, handling, cooking, and serving practices can all help reduce foodborne illness risks even with runny egg yolks.
Key points
To summarize key points on whether over medium eggs are fully cooked:
- The egg whites are always fully cooked, set, and safe to eat when eggs are prepared over medium.
- The yolks are intentionally cooked to remain runny and will not reach temperatures high enough to fully set.
- Runny yolks are favored for richer texture and eye appeal, but do pose higher risks of foodborne illness.
- Risks are still low with properly handled fresh eggs, but higher risk individuals should avoid runny yolks.
- Requesting yolks cooked through fully or using pasteurized eggs can reduce potential risks.
The bottom line
When cooked over medium, only the egg whites can be considered fully cooked through while the yolks remain deliberately undercooked. While runny yolks are not inherently unsafe, they do present increased risks especially for the very young, elderly, pregnant, or immunocompromised. Those wanting to limit risks have options like requesting fully set yolks, using pasteurized eggs, and proper cooking/handling practices.
Frequently Asked Questions
Are over medium eggs safe for pregnant women to eat?
Over medium eggs with runny, undercooked yolks are generally considered unsafe for pregnant women. Pasteurized eggs or eggs cooked fully through until the yolks are completely set are safer options during pregnancy.
Can over medium eggs contain raw egg?
Technically yes, since the yolks are deliberately undercooked and remain raw on the inside while only the outer portion thickens. The whites are always fully cooked though.
Do over medium eggs need to rest before serving?
Resting isn’t mandatory, but allowing over medium eggs to rest for a few minutes after cooking allows the residual heat to finish thickening the outer edges of the yolk slightly more. This can provide a better texture contrast between the very runny interior yolk and the warmer, thicker exterior.
Should over medium eggs be cooked covered or uncovered?
You can cook over medium eggs either covered or uncovered, depending on your preferences. Covering helps steam the tops of the whites and yolks more evenly. Uncovered allows you to better monitor the eggs while cooking and may provide more textural variation.
How do you cook an over medium egg without breaking the yolk?
Use a non-stick pan, allow eggs to come to room temp before cooking, baste hot oil over the tops as they cook, and remove before whites fully set to allow carryover cooking. Gently flipping with a spatula can keep yolks intact too.
