Yes, cooking kills both E. coli and Salmonella, but only if the food reaches the right internal temperature throughout. The critical number depends on what you’re cooking: 165°F for poultry, 160°F for ground meat and eggs, and 145°F for steaks, chops, roasts, and seafood. Undercooking, uneven heating, or contaminating food after it’s cooked can all leave you exposed.
The Temperatures That Matter
Both E. coli and Salmonella are destroyed by heat, but they don’t all die at the same threshold. The USDA sets minimum internal temperatures based on the type of food and how deeply bacteria can penetrate it:
- All poultry (breasts, whole birds, legs, wings, ground poultry, stuffing): 165°F (73.9°C)
- Ground meats (beef, pork, lamb): 160°F (71.1°C)
- Eggs and egg dishes: 160°F (71.1°C)
- Steaks, chops, and roasts (beef, pork, veal, lamb): 145°F (62.8°C), then rest for at least 3 minutes
- Fish and shellfish: 145°F (62.8°C)
At 165°F, a 7-log reduction of Salmonella happens instantly in poultry. That means 99.99999% of the bacteria are eliminated the moment the meat hits that temperature. Lower temperatures can also kill these pathogens, but they require the food to stay at that temperature for longer. This is why sous vide cooking at, say, 145°F can be safe for chicken if held at that temperature for several minutes, while a quick sear wouldn’t be enough.
Why Ground Meat Needs a Higher Temperature Than Steak
A solid steak or chop carries bacteria primarily on its outer surface, where the heat of a grill or pan reaches immediately. That’s why a medium-rare steak cooked to 145°F with a 3-minute rest is considered safe. The surface gets well above that temperature during cooking.
Ground meat is a different situation entirely. The grinding process mixes surface bacteria throughout the interior. E. coli O157:H7, the strain most associated with serious illness from undercooked burgers, can be distributed evenly from edge to center. That’s why ground beef, pork, and lamb need to reach 160°F all the way through, with no pink-is-fine exceptions. You cannot judge doneness by color alone. Burgers can turn brown before reaching a safe temperature, or stay slightly pink even after they’re fully cooked.
Why Resting Time Counts
For steaks, roasts, and chops, the USDA specifies a 3-minute rest after reaching 145°F. This isn’t just about juiciness. After you remove meat from heat, the internal temperature continues climbing 5 to 10 degrees as residual heat moves inward. That carryover cooking extends the time the hottest part of the meat stays at bacteria-killing temperatures, helping ensure pathogens in the center are destroyed. Cutting into a roast immediately short-circuits this process.
How to Check Temperature Accurately
A food thermometer is the only reliable way to know your food is safe. Insert it into the thickest part of the meat, avoiding bone or gristle, which conduct heat differently and give misleading readings. For thin items like sausage patties, slide the thermometer in from the side until the tip reaches the center. Pull the food off the heat source before checking, since leaving it over a flame can give you an artificially high reading from the cooking surface rather than the food itself.
Microwaves Create Cold Spots
Microwave ovens are particularly risky for pathogen survival because they heat food unevenly. Pockets of cool food can persist even when other parts are steaming hot, and bacteria in those cold spots survive. The USDA recommends stirring, rotating, or flipping food halfway through microwaving, then checking the temperature in multiple spots before eating. A single reading from one area isn’t enough. If you’re reheating leftovers or cooking raw meat in a microwave, test at least two or three different locations.
Cooking Doesn’t Help With Produce the Same Way
Fruits, vegetables, and especially sprouts present a different challenge. Raw sprouts are one of the highest-risk foods for Salmonella and E. coli contamination because the warm, moist conditions that seeds need to germinate (around 70–77°F with high humidity) are also ideal for bacterial growth. The bacteria can actually be present inside the seed itself, not just on the surface.
Washing sprouts with water reduces E. coli and Salmonella counts by roughly 90%, which sounds meaningful but leaves plenty of bacteria behind. Even industrial treatments with high-concentration chlorine solutions reduce Salmonella by over 99.9% without fully eliminating it. If you’re eating sprouts raw, you’re accepting some risk that no washing method can remove. Cooking sprouts until steaming hot is the only way to reliably kill the pathogens.
For other produce like leafy greens or tomatoes, thorough washing under running water helps but doesn’t guarantee safety, especially if bacteria have been absorbed through damaged skin or cut surfaces. Cooking these foods to at least 160°F eliminates the risk.
How Food Gets Recontaminated After Cooking
One of the most overlooked risks is what happens after cooking. Properly cooked food can pick up E. coli or Salmonella from cutting boards, utensils, hands, or countertops that touched raw meat earlier. The FDA notes that cooked food is actually more vulnerable to recontamination than raw food, because cooking has already wiped out the competing bacteria that would normally slow pathogen growth. A single Salmonella cell on a cutting board has less competition on a cooked chicken breast than it would on a raw one, so it can multiply faster.
The practical takeaway: use separate cutting boards for raw meat and cooked food, wash your hands after handling raw proteins, and never place cooked meat back on the same plate that held it raw. These steps matter as much as hitting the right temperature in the first place.