Wagyu Grading (BMS, USDA) and the difference between Kobe and Wagyu
What is Wagyu beef?
Credit: Japan Meat Grading Association and Japan Meat Information Service Center
Wagyu beef is specially bred to contain specific amounts of fatty acid lipids in the marbling in its meat combined with iosinic and glutamic acids which comprise the basics of umami (see here for more details on umami - what exactly is umami). This makes Japanese wagyu tastier than regular cattle due to its special breeding programs, feed, and nature of farming to enhance flavour.
According to the Japan Meat Information Service Center (which disseminates information for the Japan Meat Grading Association, there are four basic breeds of Wagyu.
Japanese Black Wagyu (Kuroge)
Historically the Japanese Black as raised as work cattle in the Kinki and Chugoku areas and through the Meiji Era (1868 – 1912, the reign of the Emperor Meiji) it was improved through cross-breeding with foreign cattle breeds. This was certified as an indigenous breed in 1944. This is the most common wagyu breed and is raised all over Japan nowadays, comprising 90% of all wagyu. This breed is fattened and raised in a certain calm environment with good quality feed which makes even the leanest parts of the cow have marbling – this marbling is of a creamy texture, further tenderising the meat so that it dissolves in the mouth.
Japanese Brown Wagyu (Akage)
The Japanese Brown or Akaushi (red cattle) is historically a breed from the Kumamoto and Kochi Prefectures. This breed was improved by crossbreeding Simmental with Akaushi, which was formerly used as work cattle during the Meiji Era. It was certified as indigenous Japanese beef cattle in 1944. Among its characteristics is its low fat content, about 12% or less. Because it contains much lean meat, its tastiness and pleasantly firm texture is highly enjoyable. Its fat is also not very heavy, and has been attracting a great deal of attention by way of its healthiness and mild taste.
Japanese Shorthorn (Nihon Tankaku)
The Japanese Shorthorn is raised mainly in the Tohoku Region. This breed was improved by crossbreeding the Shorthorn with the indigenous Nanbu Cattle. It has been continuously improved thereafter, until its certification as indigenous Japanese beef cattle in 1957. Its meat contains much lean meat and low fat content, and has a mild and savoury flavour. It also richly contains inosinic acid and glutamic acid, which are substances that give beef its tastiness.
Japanese Polled (Mukaku)
The Japanese Polled was produced through crossbreeding of Aberdeen Angus imported from Scotland with the indigenous Japanese Black in 1920. It was further improved thereafter, and was certified as indigenous Japanese beef cattle in 1944. Its characteristics include its high lean meat content and distinctive Wagyu taste. It contains a high percentage of amino acid and has a rich chewy, meaty flavour.
The Beef Marble Score - Japanese Meat Grading Association (JMGA)
A standard determined by the Japan Meat Grading Association, having been certified by the Director-General of the Agricultural Production Bureau of the Ministry of Agriculture, Forestry and Fisheries, serving as a nationwide unified transaction standard for Japan. Beef is graded in 15 stages in a combination of Yield Grade and Quality Grade (see chart below).
Yield Grade is the ratio of meat to dressed carcass weight, and is classified into three grades, from A to C .
A: 72 and greater;
B: 69 and greater;
C: less than 69
According to numbers determined in four categories (rib eye area, rib thickness, subcutaneous fat thickness, chilled carcass weight).
Quality Grade is the classified into grades (from 5 to 1) according to marbling, meat brightness, meat firmness and texture, and fat brightness and quality.
Credit: Japan Meat Grading Association and Japan Meat Information Service Center
Marbling Grade Categories
Grade 5 (very abundant) No.8~No.12
Grade 4 (somewhat abundant) No.5~No.7
Grade 3 (standard) No.3~No.4
[Grade 2 (somewhat scarce) No.2
Grade 1 (very scarce) No.1]
Credit: Japan Meat Grading Association (IMF = Intramuscular Fat)
According to the authors of a recent report, The Japanese Wagyu beef industry: current situation and future prospects — A review,
“In recent years, the intramuscular fat percentage in beef (longissimus muscle) from Japanese Black cattle has increased to be greater than 30%. The Japanese Black breed is genetically predisposed to producing carcass lipids containing higher concentrations of monounsaturated fatty acids than other breeds. However, there are numerous problems with the management of this breed including high production costs, disposal of untreated excrement, the requirement for imported feed, and food security risks resulting from various viral diseases introduced by imported feed.”
Feeding and Finishing Wagyu
The standards for feeding also vary and justify the cost of wagyu, according to the authors above,
“During the finishing period in particular, the most common fattening method is to provide as much concentrate as possible and rice straw ad libitum.
Overall, cattle are fed a high-energy diet twice or three times daily from 11 months of age until slaughter at 28 to 30 months of age.
From 11 to 18 months of age, the diet comprises increasing amounts of concentrate (36.8% to 86.4%, formulated feed) and decreasing amounts of roughage (Jamboree [beer bran], hay, and rice straw).
During the final stage from 18 months of age until slaughter, the diet comprises 86.4% to 84.2% concentrate and 13.6% to 15.8% roughage.
All cattle have constant access to water and blocks containing minerals, salt, and a diuretic. Total feed consumption during fattening is normally 4,000 to 5,000 kg/head, and more than 90% of the concentrate used for fattening Japanese Black cattle is imported.”
Correlation between Japanese Beef Marbling Standard numbers and crude fat content (IMF) in the longissimus thoracis muscle from Japanese Black steers from 1996 to 2004. Credit: Takafumi Gotoh, Takanori Nishimura, Keigo Kuchida, and Hideyuki Mannen, “The Japanese Wagyu beef industry: current situation and future prospects — A review”
Body location used for carcass grading in Japan, Credit: Takafumi Gotoh, Takanori Nishimura, Keigo Kuchida, and Hideyuki Mannen
Breeding Wagyu
Japan banned the export of Kuroge-washu cattle and DNA, despite exports of meat resuming to the US and other markets in 2012. This has meant that all Kuroge cattle are now (and in the past) documented with lineage so that it can be confirmed as authentic.
Internationally, we usually have a Wagyu cross (50%) and quality itself is reflected in the calm environment for the herd, feeding practices and the farm itself.
Full Blood Wagyu
This is 100% Wagyu DNA, traceable to Japanese cattle without any cross breeding. Wagyu that is Fullblood comes directly from a bull and cow whose ancestors come from Japan.
Purebred Wagyu
This is when a fullblood ox and a crossbred cow and should contain more than 93.75% wagyu DNA from the Kuroge strain.
Wagyu-Cross
Wagyu crosses contain 50% or less Kuroge DNA. These are usually Wagyu-Angus crosses.
USDA Beef Grading
USDA Grading
There are three prime grades: USDA Prime. Choice and Select with Prime being the best quality. Within these are the marbling grades: Moderately Abundant, Moderate, and Slight.