The types and percentages of various grades produced in a tea factory depend upon market demand. Also, but to a lesser extent, plucking standards and the quality of leaf play a role. In orthodox tea manufacture, the following percentages of different grades are normally produced:
Whole leaf | 15% |
Broken | 60% |
Fannings | 18% |
Dust | 4% |
Residue | 3% |
From the 15% whole leaf grades, the following three sub-grads are extracted.
FBOP | 2% |
OP | 7% |
P | 6% |
Similarly, the broken, fanning and dust grades are processed further into:
FBOP | 15% |
BOP | 36% |
OF | 10% |
BP | 7% |
BPS | 2% |
PF | 8% |
Dust | 4% |
It should be noted here that failure to produce whole leaf grades will result in reduced liquor colour and strength in broken and fanning grades.
In CTC tea, primary broken and fanning grades constitute about 20 and 50%, respectively. Secondary siftings of the same two grades yield about 9% each. Dust accounts for about 18% of the total product, leaving a residue of 3%.