Making the Grade

The Japanese meat grading standards were last changed in 1988. Beef carcasses are now cut or "ribbed" between the sixth and seventh rib throughout Japan. There are three yield grades: A, B, and C - classified by yield percentages estimated by an equation.

There are five quality grades 1, 2, 3, 4 and 5. based on marbling, meat colour and texture and fat colour and quality.

If Australia is going to raise cattle for export to Japan, it is important to have a fundamental understanding of the Japanese meat grading system.

Yield Grade

Yield score is determined by an estimated cutability percentage that is calculated by an equation which includes four carcass measurements.

The measurements are obtained at the sixth and seventh rib section. The yield grading is absolutely objective, delivering an estimated yield percentage as follows:

• Grade A - 72% and above
• Grade B - 69% and above
• Grade C - under 69%

Quality Grade

The meat quality scores are determined in terms of beef marbling, meat colour and brightness, firmness and texture of meat, colour, lustre and quality of fat. The relationship between beef marbling evaluation and classification of grade is as follows

Meat colour is evaluated across seven continuous standards. The colour range is from No. 1 down to No. 7 and carcass colour graders are preferred in Grade 1 to Grade 3.

Beef "brightness" is a factor in this evaluation. Firmness and texture of meat are evaluated by visual appraisal and classified into five grades.

The firmness measure ranges from very good to inferior and the texture of the meat is evaluated on a scale from very fine to course.

The colour, lustre and quality of fat is evaluated objectively against the Beef Fat Standards prepared as seven continuous stands, with grade No. 1 being the most desired.

The remaining two factors, lustre and quality are evaluated simultaneously by visual appraisal.

Carcass quality grade is determined by the lowest score for each of marbling, meat colour and fat colour assessments.