Vol. XVIII · Meat and Poultry Plate 2 of 11doneness, core temperature, safe minimum temperature, rare, medium-rare, well done, poultry 74 °C, minced meat 71 °C, steak 63 °C, holding time, pasteurisation of meatSH

Doneness.

A rare steak and a rare chicken breast are different risks. One has its bacteria on the outside; the other may have them in the middle.

Every meat has two temperatures that matter. One is for texture: the core temperature at which it is at its best, set by the proteins in VI.5 — beef tender and red near 52–55 °C, pork juicy near 60–63 °C, chicken breast moist near 63–66 °C held long enough, chicken legs silky near 75–85 °C. The other is for safety, and it depends on where the bacteria are. A whole cut of beef or lamb is contaminated almost only on its surface, which a sear makes safe in seconds; its sterile centre can be rare. Poultry and minced meat are different: Salmonella and Campylobacter run through poultry tissue, and mincing spreads the surface's E. coli through the whole mass.

The safety rules therefore follow the bacteria. Food agencies give simple single temperatures: in the United States 63 °C with a three-minute rest for whole cuts of beef, pork, veal and lamb, 71 °C for mince, and 74 °C for all poultry. These are instant kills, set high enough to need no timing. But killing is a matter of time as well as temperature (XII.6): held long enough, a lower temperature does the same job, which is how a chicken breast at 63 °C can be both safe and juicy. The workshop shows how long.

Below: the minutes needed at each core temperature for a 7-log kill of Salmonella in chicken and a 5-log kill of E. coli O157:H7 (course D and z values, after USDA FSIS), the temperature you choose marked, and the single-temperature rules for each meat.

What you will learn
Workshop
Kill times from the course D and z values (microbe bench): Salmonella in chicken for 7 logs, the poultry standard; E. coli O157:H7 for 5 logs, the beef standard. Single temperatures: USDA FSIS safe minimum internal temperatures. Times assume the whole piece is at that temperature; reaching it takes longer.

Temperature and time, where the bacteria are

For poultry, the 7-log kill takes about 27 minutes at 60 °C, 7.6 at 63 °C and 3.2 at 65 °C, but only about 4 seconds at 74 °C — which is why 74 °C is given as a single number. A chicken breast held at 63–65 °C for the stated minutes, as in a water bath (XVI.7) or a well-rested roast, is as safe and much juicier. For E. coli in minced beef, five logs take about 5 minutes at 60 °C and a few seconds (2 s) at 71 °C.

Practical rules. Use a probe thermometer in the thickest part (I.4), away from bone. Whole cuts of beef and lamb: cook to taste, after a hot sear on all sides. Pork: 63 °C with a rest is juicy and safe; pink pork is not underdone. Poultry: 74 °C anywhere is the simple rule; lower with a hold only when you can control and measure the time. Mince, burgers, sausages, meatballs: 71 °C right through, 74 °C for poultry mince. The vulnerable (XVII.6) should keep to the simple rules. Many countries give similar temperatures; China's catering standard asks for a core of at least 70 °C.

At the stove

Cook a chicken breast and check it with a thermometer: pull it at 63 °C and let it rest covered for ten minutes, measuring how long it stays above 60 °C. Compare its juiciness with one taken to 74 °C.

The pink colour of cooked meat is a poor guide in both directions: well-done burgers can stay pink when the meat's pH is high, and undercooked ones can turn brown early (VI.7). Only a thermometer measures doneness.

Terms

Core temperature
The temperature at the thickest part of a piece.
Instant kill
A temperature high enough that the required time is seconds.
Holding time
The minutes at a temperature needed to reach the required log reduction.
Safe minimum
An agency's single core temperature for each meat.
Safety depends on where the bacteria are: whole cuts on the surface, poultry and mince throughout. Killing takes time and temperature: 74 °C for poultry and 71 °C for mince are instant; lower works only if held.

Sources

  1. USDA Food Safety and Inspection Service, "Safe Minimum Internal Temperature Chart" (foodsafety.gov), 2024.
  2. USDA FSIS, Time-Temperature Tables for Cooking Ready-to-Eat Poultry Products (7-log Salmonella reduction in chicken, 5% fat), as republished in D. E. Baldwin, A Practical Guide to Sous Vide Cooking, and J. K. López-Alt, The Food Lab.
  3. USDA FSIS, Appendix A to the Compliance Guidelines for Meeting Lethality Performance Standards for Certain Meat and Poultry Products (time–temperature table for 6.5- and 7-log reductions of Salmonella in cooked beef).
  4. China: GB 31654-2021 (National Food Safety Standard — General Hygiene Specification for Food Service), which requires cooked food held hot above 60 °C and cold below 8 °C, and food cooked so that its core reaches at least 70 °C.