In Japan, wagyu beef is graded into five categories, from 5 (highest quality) to 1 (lowest quality). Wagyu is combined with the yield score (Usually “A” for Wagyu breeds) to give the ratings of A1 to A5.
Wagyu beef is generally considered to be the best quality beef money can buy. Due to a rare genetic defect, Wagyu breeds have more marbling than any other beef breed on the planet.
In this article, we’ll explore the different wagyu quality and yield ratings and what they mean, look at how they compare to the US grading system, and find out what makes wagyu so much better than other beef breeds.
How is Wagyu Graded?
Wagyu beef is graded by two metrics, and the overall grade is a concatenation of both metrics. The first metric is a letter representing the yield, and the second is a number representing the quality. For example, A5 represents the highest yielding, highest wagyu meat available.
Part 1: Yield Score
The first metric is the yield score, which measures the amount of usable meat on each carcass, a sign of quality and good muscling.
The Japanese system measures yield using a complex calculation to come up with a numerical score using four different metrics and measurements that can be performed on the carcass to estimate the percentage of usable meat from each carcass.
The yield is calculated with the following metrics:
- Area of the rib eye in cm2
- Thickness of the short ribs in cm
- Overall weight of the half carcass in kg
- Subcutaneous fat width in cm
In addition, all meat breeds (which include every breed of Wagyu) are granted an additional few points on the score, to account for the fact that wagyu is a small framed breed with high levels of muscle and fat.
Through a calculation involving each of these metrics, each carcass is graded from A to C, depending on the expected yield of each carcass.
A: Above Average Yield
B: Average Yield
C: Below Average Yield
The yield score doesn’t say anything about the quality of the meat, only the expected yield, however, a higher yield can indicate more developed muscles and a healthier body, which will be reflected in the quality score, so it’s often a good indication.
Read More: How Many Steaks Can One Cow Make?
Part 2: Quality Score
The second part of the Japanese wagyu rating system is the quality score.
Quality is graded on a scale of 1 to 12, with 1 being the poorest quality meat and 12 being the highest quality.
Meat is then put into the correct category (from 1-5) according to its quality score and this category makes up its official rating.
Wagyu Quality Scores and Corresponding Categories:
|Quality Score||Quality Category||Description|
Source: American Wagyu Association
Wagyu Quality Criteria
Wagyu beef quality is determined by four tests. The meat is assigned a grade from 1 to 5 for each category, depending on the quality.
The overall grade of the meat is designated according to the lowest category.
For example, if the carcass scored 5, 5, 5, and 3, it would be classified as grade 3 quality beef.
Let’s take a look at each of the criteria and see what they mean:
Marbling is the amount of intramuscular fat present in the meat. More is better, since it makes the beef more tender, tastier, and prevents it from drying out during cooking.
Wagyu cattle have a rare genetic mutation that allows them to store much more fat intramuscularly, giving wagyu beef its characteristic marbling.
Read More: Why Are Cows Fat?
2: Fat Color
The color of the exterior and intramuscular fat is graded on a scale of 1-7 with the results being plotted appropriately to the 12 point rating scale.
Fat is more desirable when it’s white in color, and the more yellow/pink the fat is the lower the quality score.
3: Beef Color and Brightness
The color of the meat itself is an important indicator of the quality of the meat.
A brighter red indicates that the meat is healthy, and few blood vessels and capillaries have burst.
Damaged or stressed meat is sometimes called dark meat and generally isn’t used for steaks, but is instead used for secondary beef processing products like hotdogs or dog food.
Brighter, more vividly red meat gets a higher score than darker, brown colored meat.
4: Firmness and Texture
Wagyu beef is highly prized for its fine-textured, tender meat.
This is generally due to the farming techniques of Wagyu, which involve looking after the cattle and preventing them from becoming stressed or having to work, to keep their meat tender.
This has led to many folk tales about farmers massaging wagyu beef, serenading them with classical music, or even letting them drink beer!
Read More: Do Cows Like Music?
Wagyu is assessed for firmness and texture and put into one of five categories:
|5||Very Good||Very Fine|
|2||Below Average||Below Average|
Read Next: How much does it cost to butcher a cow?
To sum up, Japanese Wagyu are graded by a dual system that measures both yield and quality.
Yield is measured on a scale of A to C, with A being the highest yield, and quality is measured on a score of 1-12, with 12 being the highest possible quality.
The quality score is then put into a parent category between 1 and 5 and this makes up the final grade.
The highest quality beef available is A5 grade, which means that the yield is grade A (above average) and the quality is grade 5 (excellent) which corresponds to a score of between 8 and 12 on the full quality scale.
Stuart is the editor of Fauna Facts. He edits our writers’ work as well as contributing his own content. Stuart is passionate about sustainable farming and animal welfare and has written extensively on cows and geese for the site.