Abstract:Lycium barbarum L. (goji) is one of the most important economic crops with well-known and widely consumed fruits as both medicine and functional fruits in Northwest China. In order to explore a novel way to identify producing areas of goji, the moisture absorption rate and floating rate of dry fruits collected from 24 producing areas were detected. The results showed that the moisture absorption rate and floating rate of goji fruits from the same producing area were stable and not affected by desiccation method, cultivar, tree age and harvest time. Goji from different producing areas had different floating rate and moisture absorption rate. The moisture absorption rate of fruits from Guyuan was 1.47%, which was significantly lower than those from other producing areas except Jingyuan, Yumen or Wuwei (P<0.05), whereas goji from Guazhou showed the highest moisture rate with 2.87%. The floating rate of fruits from Urad Qianqi, Huinong, Jingyuan and Zhongning were 95.56%, 95.00%, 94.44% and 93.29%, respectively, and were significantly higher than those from Gonghe, Golmud, Jinghe, Wuwei, Yuli, Guazhou, and Altay areas (76.67%, 73.89%, 73.13%, 71.67%, 67.67%, 66.39%, 65.00%, respectively) (P<0.05). Principal component analysis (PCA) of floating rate and moisture absorption rate showed that the spots of fruits with the same producing area were concentrated, the fruits from Guazhou, Golmud could be distinguished from other producing areas. Therefore, floating rate and moisture absorption rate could be used for identification of producing areas of goji fruits.
