Ground Beef vs Steak: Why the Same Cow Has Different Safety Rules

It seems odd that two products from the same animal — ground beef and steak — have different safe cooking temperatures. Steak only needs to reach 145°F with a three-minute rest. Ground beef must reach 160°F throughout. The difference isn’t arbitrary. It comes from one straightforward fact about where bacteria live in meat.

Surface vs. Interior Contamination

Bacteria don’t penetrate intact muscle tissue. They live on surfaces — the outside of the meat, where they arrived from the animal’s hide, intestinal contents, and processing equipment during slaughter.

When you buy a steak, the bacteria are on the exterior. Searing creates surface temperatures above 400°F. At that temperature, bacteria die in fractions of a second. The interior of the steak stays essentially sterile because bacteria never made it there. This is why a rare steak — with a red, 130°F center — is a food safety non-issue for a healthy adult. The surface contamination has been destroyed. The interior was never contaminated.

Grinding changes everything.

When beef is ground, the surface of the meat — the part carrying bacterial contamination — gets mixed throughout the entire product. Every cubic centimeter of a burger patty now contains what was on the outside of the original cuts. The contamination that was once isolated on a surface is now uniformly distributed, center to edge.

A burger’s center can harbor E. coli O157:H7 just as much as its exterior. So the center must reach a kill temperature too. That temperature is 160°F for ground beef, set by the USDA based on E. coli thermal kill kinetics.

The Multiple-Animal Problem

There’s a second layer to the ground beef risk that doesn’t exist with steaks: the multi-source problem.

A single steak comes from one animal. If that animal’s meat is contaminated, the contamination is in that specific cut. When you grind your own steak, the ground meat comes from one source.

Commercial ground beef is different. A package of supermarket ground beef typically contains meat from multiple animals — sometimes hundreds of cows processed and mixed together. One contaminated carcass can spread bacteria through an entire production batch.

This is why E. coli O157:H7 ground beef recalls often involve tens of thousands of pounds of product. A single contamination event at a processing facility can affect ground beef distributed across many states. The 2019 JBS beef recall involved 12 million pounds of ground beef products. One contamination source. Enormous reach.

The Temperature Rules by Meat Type

The grinding principle applies across all ground meats. The USDA minimum safe temperatures:

Sausages made from ground meat follow ground-meat rules, not whole-muscle rules. A pork sausage link or a beef bratwurst needs to reach 160°F throughout, not 145°F.

The Restaurant Burger Question

The USDA requires ground beef to be cooked to 160°F. But many restaurants offer medium or medium-rare burgers. They’re technically not compliant with federal recommendations, and many states have their own regulations on this.

Some restaurants use alternatives to reduce risk. High-pressure processing (HPP) treats ground beef before cooking to reduce pathogen loads. Some use sous vide pre-cooking followed by a sear. Some grind whole cuts to order for single-source traceability.

If you order a medium-rare burger at a restaurant, the risk is real but low in most establishments with good sourcing. If you’re in a high-risk group — pregnant, elderly, immunocompromised, or feeding young children — stick to well-done at 160°F. The E. coli article covers the specific pathogen involved in ground beef contamination in more detail.

The rule is easy to remember once you understand why it exists. Surface contamination: sear the outside, call it done. Interior contamination from grinding: every part needs to reach the kill temperature. A thermometer confirms the difference. The safe internal temperatures guide has the complete reference table.