Quality of saffron is based on 3 factors:
Crocin is a chemical that is responsible for the color of Saffron. The higher the Crocin the higher the coloring strength of Saffron. Customers demand high Crocin level Saffron.
Safranal is a constituent responsible for the aroma of Saffron. In other words, it is why saffron smells how it does.
Picrocrocin is why saffron tastes a little bit bitter and it is responsible for the taste of Saffron.
All Red Sargol
1 Crocin (Coloring Strength) minimum 205-225
2 Safranal (flavor & smell) minimum 35
3 Picrocrocin (bitterness) minimum 80
4 Moisture under 8%