Abstract:Objective To analyze and identify the coloring components in lotus root powder, clarify the reasons for the different colors of lotus root powder, and analyze the color variation patterns during brewing.Methods Five commercially available lotus root powder samples are analyzed. Acid-base chromogenic reactions and ultraviolet-visible (UV-Vis) spectroscopy are employed to preliminarily identify the chromogenic components. Ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and Fourier transform infrared spectroscopy (FT-IR) are used to determine their composition and structural units.Results The chromogenic components in lotus root powder are identified as proanthocyanidins, primarily oligomeric proanthocyanidins composed of catechins and epicatechins, with relative molecular weights predominantly below 896. The main structural unit is (-)-epicatechin. The proanthocyanidin content in the five commercially available samples ranges from 0.080 to 0.150 mg/g. In the high-content sample (0.147 mg/g), the levels of anthocyanins, total polyphenols, and total flavonoids are (0.001 1±0.000 3), (0.262±0.003) mg GAE/g, and (0.348±0.008) mg/g, respectively.Conclusion The color differences in lotus root powder are primarily attributed to proanthocyanidin content and storage conditions (temperature and duration).