Quality Analysis and Evaluation Standard Construction of Fresh Goji (Lycium barbarum L.) Pulp

In this paper, 46 fresh goji pulp products randomly selected from the market were compared and analyzed through the main components, color, flavor and other indicators, and the evaluation standard was preliminarily established. The results showed that the samples of fresh goji pulp showed good nutritional and flavor characteristics, but the quality of different products varied greatly. The pH ranged from 4.04~4.62, the viscosity ranged from 6.63~116.60 cP, the soluble solids ranged from 12.77%~30.63%, the total sugar content ranged from 93.19~220.26 mg/g, the flavonoid content ranged from 23.43~87.27 μg/g, and the total carotenoid content ranged from 3.23~1579.47 μg/g. The color of the samples was bright orange-red, and the samples responded to the eight flavor characteristics of umami, sour, astringency and saltness. Alkanes, alcohols, and volatile sulfides were the most varied compounds in the odor analysis. Based on principal component analysis, the correlation degree and contribution degree of each index and the main component were obtained, the quality evaluation index of fresh goji pulp was established, the grading standard of evaluation index was established by probability classification, and the evaluation standard of quality was constructed by analytic hierarchy process, and the comprehensive score of each sample of fresh goji pulp was obtained, which provided data reference for quality evaluation and standard formulation of fresh goji pulp.