A Series of natural circumstances will produce variations in cocoon quality. Some of the most noteworthy include:
Differences in cocoon quality in the same batch
Differences in cocoons produced in the same location by different farmers who have reared the same speciesSeasonal influences. In Japan for example, cocoons produced in the spring and late autumn are higher in quality than those in early autumn and summer
Environmental conditions affect cocoon reelability such as temperature and humidity
Processing technique in reeling will impact reeling efficiency as well as raw silk quality
Bivoltine cocoons are superior quality compared to multivoltine silkworm species traditional farmed in tropical zones.
Recent silkworm cultivation now develops cross-breeds of multivoltine with bivoltine silkworms as a strategy to improve overall cocoon quality.