2.1. Samples
A total of 117 Shaoxing rice wines were provided by three wellknown
wineries. Amongst, 40 samples were from ‘‘Guyuelongshan Guyuelongshan’’
winery. 40 samples were from ‘‘Kuaijishan’’ winery, and
the remaining 37 samples were from ‘‘Pagoda’’ winery. Shaoxing
rice wine, from which Chinese rice wine originated, is the most famous
and representative in China. It is also labelled as the product
of protected designation of origin (PDO) by Chinese National Standard
GB 17946-2000 (Shen et al., 2010). In this study, 109 samples
used were semi-dry wines; the remaining 8 samples were dry
wines. All the samples were from the vintage year of 2007 and they
were aged for different periods (27 samples, 3 months; 30 samples,
9 months; 30 samples, 15 months and 30 samples, 21 months) before
analysed in the laboratory. Each sample used was selected
from different batches of production and directly taken from storage
containers without any additive.