Beef grading gets an upgrade

Trying to make kabobs out of stewing meat is going to be a wasted effort.

“As a society, North America-wide, there is a loss of cooking ability generally across the board,” said Marty Carpenter, chair of the Canadian Beef Grading Agency and formerly with Canada Beef Inc.

Carpenter is also a chef and he knows that people today are gravitating toward more convenient, easy-to-prepare products. Consumers look for guidance on meat labels but many remain confused.

Beef carries quality grades based on marbling but many consumers are unsure what A, AA and AAA mean and how to cook different cuts to get the best results.

Major retailers like Costco and WalMart have switched to Canada AAA programs because of a perceived link with quality.

Consequently there is not much A or AA product available.

“Those two categories are actually shrinking as we go forward because more and more retailers and restaurants gravitate toward that AAA target. That is where we see the majority of our beef being produced,” Carpenter said.

Grading ranks the amount of marbling, which is responsible for flavour and juiciness. Results vary throughout the year but almost 60 percent of carcasses are AAA compared to about a quarter of carcasses in the 1990s.

“Over the course of 20 plus years, we have been able to double the amount of beef in the best categories of AAA and Prime,” Carpenter said.

Prime makes up one to two percent of the total production but producers are generally aiming for AAA because that is what restaurants and retailers request.

A new Certified Tender from Cargill Meats goes one step further with its Sterling Silver beef line of premium AAA selections.

The new label appears on four different cuts of beef and is available at Sobey’s and Safeway.

“It is something the consumer can visibly see and make them feel confident in what they are eating,” said Tanya Thompson of Cargill Meats.

Tenderloin, ribeye and strip loin qualify. The cuts must be derived from the top end of AAA and aged a minimum 14 days.

Samples are submitted for shear force tests to assess tenderness.

The program is certified through the Canadian grading agency.

Since the first National Beef Quality Audit in 1995, tenderness was cited as the number one consideration for consumers. Improvements have been made because of changes in feeding practices, cattle genetics and enhancements done at the packing plant.

Electrical stimulation of the beef carcass and controlled carcass chilling as well as aging of certain beef cuts in temperature-controlled environments enhance tenderness through the actions of natural enzymes that soften muscle fibers.

Heather Bruce of the University of Alberta studies the nuances of beef tenderness. A particular area of research is examining collagen, the most abundant protein in the body that serves as a connector.

Collagen can look like a honeycomb holding the muscles together, she said.

There are different types of collagen that pervade the whole muscle so it can impact toughness.

Large amounts of collagen are often associated with tough meat along with other factors like production practices, age of animal, growth rate, use of steroids, breed and muscle type.

“The less collagen interferes with the eating experience the shorter the cooking time. We pay for the convenience of cooking low connective tissue meat like sirloin, ribeye and sometimes top sirloin from young animals,” she said in an interview.

Cooking techniques can make a difference.

Typically, both the amount of connective tissue and the resistance of collagen to break down during cooking increases as animals grow older.

Muscles used for movement have more connective tissue while other muscles are more tender.

Brisket has a lot of connective tissue but it is perfect for long cooking times.

“Eye of round reaches its total collagen plateau early because it is used as a locomotion muscle,” she said.

Her work is trying to gain insight into what is happening to meat at the cellular level.

“One of the things we are looking for is animals that have a high level of degradation of collagen in the post-mortem aging period,” Bruce said.

In a large genomics program at the University of Alberta, genetics are studied for their influence on tenderness.

“Angus genetics seem to have an inherent ability for increased degradation post-mortem. They seem to have greater tenderization occurring post-mortem and that is attributed to increased ability of their calpains, which are enzymes that will degrade muscle proteins,” Bruce said.

Aging helps tenderize the meat and research has shown 14 days of aging is probably sufficient.

Her team has not investigated dry versus wet aging but the technique appears to affect flavour versus tenderness.

Growth promoting hormones and beta agonists do not seem to affect the amount of collagen but the effect depends on the muscle tissue composition.

Other research looked at the toughness of meat using the Warner Braztler shear force test. This is a mechanical measurement to show how much force is needed to cut through a piece of meat.

Researchers have looked at different grades and found some surprising results.

“The only one that tends to be tougher is AA. The single A that is out there is as tender as AAA. It just has lower fat,” she said.

They are not sure why that is so but it may be linked to the growth stage of the animal. The longer an animal is fed, the more fat, including marbling is added.

“Marbling is very much a function of age, not just weight,” Bruce said.

Other work is being completed using near infrared predictions for tenderness.

All this work should lead to better beef.

“Once you understand the effects of all the different pathways to meat quality, you only need to do a little bit of research to understand what tweaking will do,” she said.

Bruce argues standard operating procedures should be developed to produce quality beef. This approach already exists in other sectors like grapes for wine making for example.


About the author


Stories from our other publications