Abstract:

Broken rice was used to make rice tea after soaking and roasting. In the process, the occurrence of Maillard reaction and caramelization could produce pigment materials that make rice tea infusion colorful. The effects of making parameters and infusing time on the color parameters of rice tea: lightness (L*), redness (a*), yellowness (b*) and chroma (c*) were investigated. The results showed that the orange color turned to pure yellowness and tea lightness decreased with prolonged infusing time. The process of color formation followed an exponential model. Furthermore, rice soaking could influence the color of rice tea. Rice tea resulting from 10 min soaking at a material-to-water ratio of 1:20 (m/V) could quickly show stable color with high lightness, yellowness and chroma.

Key words: rice tea, infusion, color, kinetics