Evaluation of dynamic changes in the bioactive components in Citri Reticulatae Pericarpium (Citrus reticulata 'Chachi') under different harvesting and drying conditions

BACKGROUND The Citrus reticulata 'Chachi' pericarp (CRCP) is one cultivar of Citri Reticulatae Pericarpium (Chenpi), which is widely applied in medicine and food. To determine the potential value of CRCP harvested at different stages and subjected to different drying processes, the dynamic changes in the bioactive components were profiled and evaluated in this study. RESULTS The contents of all non-volatile components, i.e. synephrine, limonin, phenolic acids and flavonoids, decreased with delayed harvest time. The volatiles thujene, alpha-pinene, beta-pinene, d-citronellol, d-citronellal, decanal, linalool, geraniol, l-cis-carveol, terpinen-4-ol, alpha-terpineol, carvacrol, perillaldehyde, methyl 2-(methylamino)benzoate and d-limonene were considered the characteristic components for distinguishing CRCP harvested at different stages. Phenolic acids, synephrine and limonin were stable at different drying temperatures; however, high-temperature drying at 60 degrees C induced a significant transformation in the flavonoids (especially polymethoxyflavones) and volatile substances in CRCP. CONCLUSIONS The results suggested that most of the bioactive components declined with the growth of Citrus reticulata 'Chachi'. And it is believed that the fresh peel should be naturally sun-dried or dried at low temperature (30 or 45 degrees C) rather than at high temperature (60 degrees C) to prevent excessive loss of nutrients. (c) 2020 Society of Chemical Industry

Automated summary

Most bioactive components in Citrus reticulata 'Chachi' decline with growth, suggesting that fresh peel should be naturally sun-dried or dried at low temperature to prevent excessive loss of nutrients. High-temperature drying has a significant impact on flavonoids and volatile substances in CRCP.