Microbes in Raw Meat

Contamination of food by microbes is a public health concern around the world. Episodes of food poisoning due to microbial contamination have led to a large number of food recalls over the years, particularly of meat products that have caused outbreaks of dangerous illnesses.

Image Credit: Billion Photos / Shutterstock
Image Credit: Billion Photos / Shutterstock

How Microbes Contaminate Meat

The growth of microbes in meat is governed by a number of intrinsic and extrinsic factors. Intrinsic properties of meat, such as pH and moisture can promote microbial growth, whereas temperature is an extrinsic factor.

Fresh meat has a high water content that is favorable for the growth of microorganisms. It also generally contains bacteria, including those that can cause diseases. The animals naturally carry bacterial species like Salmonella and E. coli in their intestines, and raw meat can become contaminated during the slaughter process.

Equipment and tools used in the processing of meat can also become contaminated with microbes and spread to the raw meat.

Bacteria multiply rapidly at temperatures from 40 °F to 140 °F. Pathogenic bacteria do not necessarily multiply in meat leading to illness. Some species such as Staphylococcus aureus tend to be outcompeted by other harmless flora or spoilage bacteria that lead to a bad odor that causes most consumers to discard the meat.

Bacteria Staphylococcus aureus on the surface of skin or mucous membrane, 3D illustration. Image Credit: Kateryna Kon / Shutterstock
Bacteria Staphylococcus aureus. Image Credit: Kateryna Kon / Shutterstock.com

Preventing Contamination in Different Kinds of Meat

Food poisoning due to microbial contamination of meat can be prevented by cooking the meat thoroughly before consumption and observing good hygiene practices when cooking and handling meat. This includes the use of clean utensils, cutting boards, knives, and prevention of cross-contamination between raw meat and ready-to-eat foods. If there is a lapse in safe handling practices, cooked meat may still become tainted through cross-contamination.

The spores of some pathogenic bacteria, such as Clostridium perfringens are not easily destroyed during cooking. The heat of cooking can activate those spores to germinate and develop into mature bacteria if the food is kept at ambient temperature for a prolonged period.

Clostridium perfringens bacteria, anaerobic spore-producing bacteria, the causative agent of gas gangrene infection and food poisoning, 3D illustration. Image Credit: Kateryna Kon / Shutterstock
Clostridium perfringens bacteria. Image Credit: Kateryna Kon/Shutterstock.com

Raw meat should be cooked thoroughly before consumption. Ready-to-eat cooked meat should be discarded if it has been at room temperature for more than four hours. Cooked and raw meat should be stored in a refrigerator.


The most common pathogenic bacteria found in beef is Escherichia coli. The E. coli strain O157: H7 is a rare, dangerous bacterium that can cause severe damage to the intestinal lining. Salmonella, Staphylococcus aureus, and Listeria monocytogenes are also common contaminants in beef. All of these organisms can be destroyed by cooking.


In pork, E. coli, Salmonella, S. aureus, and Yersinia enterocolitica are the most common bacterial contaminants. Chitterlings (intestine) can be contaminated with Y. enterocolitica, leading to a diarrheal illness known as yersiniosis. Microbial contaminants in pork can be destroyed by cooking to an internal temperature of 145 °F.


Chicken is often contaminated with Salmonella enteritidis. S. aureus, Campylobacter jejuni, L. monocytogenes, and E. coli can also be found in chicken. Chicken should be cooked to an internal temperature of 165 ° F to kill the microbes.


Further Reading

Last Updated: Jan 11, 2023

Dr. Catherine Shaffer

Written by

Dr. Catherine Shaffer

Catherine Shaffer is a freelance science and health writer from Michigan. She has written for a wide variety of trade and consumer publications on life sciences topics, particularly in the area of drug discovery and development. She holds a Ph.D. in Biological Chemistry and began her career as a laboratory researcher before transitioning to science writing. She also writes and publishes fiction, and in her free time enjoys yoga, biking, and taking care of her pets.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Shaffer, Catherine. (2023, January 11). Microbes in Raw Meat. AZoLifeSciences. Retrieved on May 28, 2024 from https://www.azolifesciences.com/article/Microbes-in-Raw-Meat.aspx.

  • MLA

    Shaffer, Catherine. "Microbes in Raw Meat". AZoLifeSciences. 28 May 2024. <https://www.azolifesciences.com/article/Microbes-in-Raw-Meat.aspx>.

  • Chicago

    Shaffer, Catherine. "Microbes in Raw Meat". AZoLifeSciences. https://www.azolifesciences.com/article/Microbes-in-Raw-Meat.aspx. (accessed May 28, 2024).

  • Harvard

    Shaffer, Catherine. 2023. Microbes in Raw Meat. AZoLifeSciences, viewed 28 May 2024, https://www.azolifesciences.com/article/Microbes-in-Raw-Meat.aspx.


  1. sahar Hemeda sahar Hemeda Sudan says:

    I am wondering, If there is any standard for the existence of  bacteria? or the beef meat should be free from pathogen?

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoLifeSciences.
Post a new comment

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.