Carotenoid content of Goji berries: CIELAB, HPLC-DAD analyses and quantitative correlation

Fruits of Lycium barbarum L., have been used in Chinese traditional medicine for centuries. In the last decade, there has been much interest in the potential health benefits of many biologically constituents of these fruits. The high level of carotenoids offers protection against development of cardiovascular diseases, diabetes and related comorbidities. In the present work two different selections of Lycium barbarum L., cultivated in Italy and coming from three discrete harvest stages, were subjected to two different grinding procedure and to a simplified extraction method of carotenoid component. CIELAB colorimetric analysis of the freshly prepared purees and HPLC-DAD analysis of carotenoid extracts were performed and compared. Different harvesting dates and grinding procedures deeply influence the carotenoids content and statistical analysis showed high correlation between carotenoid content and colorimetric data. The final model provides a reliable tool to directly assess carotenoid content by performing cheap and routinely colorimetric analyses for food industry.