What is Wagyu?

The term "Wagyu" refers to the four breeds of Japanese Black, Brown, Hornless, and Japanese Shorthorn, as well as their crossbreeds. Therefore, cattle produced overseas are not recognized as Wagyu, even if they are improved Japanese breeds.

Since sperm and embryos from Wagyu cattle taken for research purposes in Colorado, U.S.A. in 1976 were leaked to other countries, and mixed cattle crossed with other breeds in Australia and the U.S. are now more common as Wagyu than those from Japan, the Japanese government provides official recognition to distinguish them.

Most of today's Wagyu are improved Wagyu that have been fixed as a breed through crossbreeding with foreign breeds. Among them, the Kuroge-Wagyu accounts for about 97%. The reason why the Black Wagyu has become the mainstream is because it tends to produce marbled meat.

The first characteristic of Wagyu beef meat is that it has a high ratio of intramuscular fat with a fine layer of fat in the lean meat. This is what is called "marbled meat" or "deer meat. However, of the four Wagyu breeds, only the Black Japanese breed has this characteristic, while the other three breeds do not have a high degree of marbling. The degree of marbling varies depending on sex, castration, and fattening method, but in the case of the Black Wagyu, it is believed that genes play a major role.

The fat of the Black Wagyu is also known for its high content of monounsaturated fatty acids (e.g., oleic acid). Generally, the melting point of beef fat is between 40 and 50 degrees Celsius, but monounsaturated fatty acids have a lower melting point, so the melting point of Wagyu beef fat is below that of butter (around 30 degrees Celsius). Therefore, the fat melts at body temperature as soon as it is put in the mouth, and this is thought to be one of the major factors that produce the tender, melt-in-your-mouth texture unique to Wagyu beef, as well as the marbling.

Wagyu beef, especially the black Wagyu breed, is known to have a unique sweet aroma called "Wagyu Aroma," which is thought to be caused by complex compounds such as lactones. Lactones are aroma components also found in peaches and coconuts, and Wagyu contains more of them than imported meats, and the aroma increases when heated.

How to define Wagyu grades?

Japanese beef is graded by the Japan Meat Grading Agency into yield grade and meat quality grade, with A being the highest yield grade. Meat quality grades are determined by the B.M.S. (Beef Marbling Standard), B.C.S. (Beef Coloring Standard), B.F.S. (Beef Fat Standard), and other grades. The B.M.S. is rated on a 5-point scale, while the B.C.S. and B.F.S. are rated on a 12-point scale and a 7-point scale, respectively.

Wagyu farmers, especially fattening farmers, place great importance on Sashi (Marbling), or BMS, as it has the greatest influence on the meat quality grade, and the finer it is, the higher the grade and the higher the unit price per kilogram.