Qualitative and nutritional comparison of goji berry fruits produced in organic and conventional systems

Abstract

Goji berries are fruits widely cultivated in Asian countries and have been consumed all over the world due to the high content of nutrients. In this paper, nutrient composition including moisture, ash, minerals (including heavy metals), proteins, lipids (including fatty acids), available carbohydrates (including soluble sugars), organic acids and dietary fiber were determined in organic and conventionally cultivated goji fruits. Physicochemical properties, total titratable acidity, pH, soluble solids, water activity and color were also investigated. Goji berries presented higher contents of available total sugars (67.85 and 75.05%), dietary fiber and essential minerals (Mg, Fe, Zn, Cu and Mn). Fructose was the main soluble sugar identified in organic and conventional fruits (5.45 and 4.92 g/100 g, respectively), followed by glucose and sucrose. Conventional fruits presented Hg and Pb contents above the established limits by the Codex Alimentarius. The linoleic acid was the main fatty acid identified in organic (54.68%) and conventional (37.06%) goji berry. Fructose was the main soluble sugar identified in organic and conventional fruits (5.45 and 4.92 g/100 g, respectively), followed by glucose and sucrose. Citric acid was identified as the main organic acid present in organic and conventional goji berries (0.90 and 1.14 g/100 g, respectively). The parameters, total titratable acidity, pH, soluble solids and water activity were considered as sensorial desirable in both samples. The color parameters indicated the red-orange coloration as predominant in the samples. These results demonstrate that goji fruits present high nutritional and sensory potential as ingredients in the formulation of foods, cosmetics and medicines. However, goji fruits grown in organic systems are better alternatives to ensure the food safety of industrialized products due to its lower content on heavy metals (Cd, Hg and Pb).