Classification of goji berry (Lycium barbarum L.) varieties according to physicochemical and bioactive signature

Abstract

Goji berries (L. barbarum L.) are characterised by a high content of bioactive compounds that make them one of the so-called ‘superfoods’. Due to the growing demand for goji berries, a great interest in this crop is being generated in Europe. Therefore, this study determined the physicochemical and bioactive composition of eight varieties of goji berries cultivated in Southwest Spain. Results showed that glucose (13.7–48.6 g 100 g⁻¹) and fructose (13.8–35.2 g 100 g⁻¹) were the major sugars. The main organic acids found were succinic (0.92–2.16 g 100 g⁻¹), tartaric (0.91–2.03 g 100 g⁻¹), and citric (0.36–4.50 g 100 g⁻¹). Carotenoid analysis showed zeaxanthin being the predominant carotenoid compound (279–1044 μg g⁻¹), while the chlorogenic acid (540–1077 μg g⁻¹) was the majority phenolic compound. In addition, antioxidant activity showed values between 6.7 to 17.6 mg Trolox equivalents g⁻¹. Finally, principal component analysis classified the varieties into three groups, which allowed similarities to be established between them. The bioactive knowledge of the varieties in the studied growing area allows maximizing the potential of goji berries as functional products.