Project Summary

NAMP/KSU Survey for Blade Tenderization

Principle Investigator(s):
Ann Rasor
North American Meat Processors Association (NAMP)
Completion Date:
May 2003



In January of 1999, the Food Safety and Inspection Service (FSIS) issued a policy clarification indicating that E. coli O157:H7 was an adulterant in all non-intact beef products, or in meat that would be consumed as a non-intact product, including trimmings and mechanically tenderized beef. Blade-tenderization of beef is a common industry practice that increases the tenderness of beef products, and processors were immediately concerned that the use of this process could be in jeopardy, despite the fact that no illness had been linked to these products. Research conducted at Kansas State University had shown that blade-tenderized steaks, when cooked to varying degrees of doneness, had shown no more risk than non-tenderized steaks, if cooked to medium rare. The National Advisory Committee on Microbiological Criteria for Foods reviewed the issue and the relevant research for FSIS. While no recommendations were made for any regulatory changes regarding these products, they were unable to support the claim that blade-tenderized steaks provided no greater risk than non-tenderized steaks, only that this was true if cooked to 140°F (rare). FSIS also conducted a risk assessment which concluded, “the probability of E. coli O157:H7 surviving typical cooking practices in either tenderized or not-tenderized steaks, is minuscule.”  Still FSIS officials had indicated that there was a need for more information on both industry and consumer practices in order to resolve the issue. FSIS also indicated their desire to have industry create Good Manufacturing Practices for the mechanical tenderization of beef products.

The stated objectives for this work were: NAMP and NCBA will use these 2 surveys to develop Good Manufacturing Practices (GMPs) for the use of blade tenderization of both primals and sub-primals by the meat processing industry.


A questionnaire was distributed to 500 individuals through personal contact, email, and telephone. The questionnaire consisted of the following nine questions.

  1. Where do you cook steaks and/or roasts (check all that apply)? (Home, Hotel/Restaurant, Institution/Hospital School)
  2. How do you determine doneness? (Check temperature using a thermometer, Use meat color as an indicator, use cooking time as an indicator) If yes to using a thermometer, do you know what minimum internal temperature to cook your steak or roast? (Yes, No) If yes, what temperature?
  3. What level of doneness do you prefer or typically prepare (Check all that apply)? (Rare, Medium Rare, Medium, Medium Well, Well)
  4. What is the most common thickness of steaks you prepare (check all that apply)? (½ inch or smaller, ¾ inch, 1 inch, 1 ¼ inch, 1 ½ inch or larger)
  5. Are your steaks usually frozen and thawed prior to cooking? (Yes, No, Do Not Freeze Steaks)
  6. What method do you use to cook your steaks (Check all that apply)? (Home Grill, Pan Fry, Commercial Grill, Oven Broil)
  7. Do you tenderize your steaks before cooking? (Yes All Cuts, Yes Some Cuts, No Cuts – Go to question 9)
  8. What do you use to tenderize your steaks? (Chemical Meat Tenderizer – i.e. Papain, Mechanical Meat Tenderizer – i.e. Mallet)
  9.  Do you marinate your steaks before cooking? (Always, Sometimes, Never)


The scientific research completed on blade-tenderized steaks has shown that when cooked to rare temperatures, blade tenderized steaks are equally as safe as non-tenderized steaks. Two surveys were completed to gather more information about the subject, the first to determine the extent and use of blade tenderization in the beef industry and the second to determine common consumer cooking practices for products that could potentially be blade tenderized.

The first survey shows a decrease in the use of blade tenderization in the last 3 years (54% compared to 84%), but the use of other tenderizing machines (dicers, cubers, etc.) is still popular. While most companies trim subprimals before blade tenderizing, most do so more for customer specifications than for food safety. Pathogen interventions other than trimming are used by only 22% of companies, probably due to expense or lack of validated technologies available. A complete breakdown of equipment for cleaning and sanitizing is performed at the end of each day by a majority of companies. Only 25% of the companies who blade tenderize also pump their product. The largest companies continue to produce the majority of blade-tenderized and injected meats.  

The consumer survey showed that most consumers used color to indicate doneness of steaks, and cooking times for roasts. None of those who were surveyed knew the recommended minimum internal temperature for cooking steaks and roasts. Only 5% of consumers cooked their steaks rare, with 82% preferring medium and above. Most consumers preferred their steaks at least ¾ inch thick, and home grilling was the preferred method of preparation for the vast majority of respondents.


The results indicate that most consumers cook their steaks above the temperature recommended in the FDA food code and that production practices for blade tenderizing, such as trimming and other interventions, combined with sanitation activities, provide an additional barrier of protection from the introduction of pathogens into the steaks. The development and use of GMPs for blade tenderizing should further reduce the already miniscule risk associated with these products.