The Anthocyanins Content, Colour Changes and Thermal Stability of Roselle (Hibiscus sabdariffa L.) Petal Extract

The objectives of this study were to determine the effect of heating treatment on anthocyanin stability and discoloration and to determine the degradation kinetics of anthocyanins and color of rosella petal extract. The results showedthat temperature and heating time significantly affected on anthocyanin content, discoloration, and stability of anthocyanin extract of roselle petals. Thermal degradation of anthocyanin and color (a* and C*) decreased, while L*, b*, Ho, and E increased along with the increase of temperature and time. In addition, the results of the study also showed that higher temperatures and longer storage caused a faster rate of degradation (higher k-value) and the shelf life (t1/2) were shorter. It was clearly seen that anthocyanins were more stable at higher temperature with shorter time compared to heating at lower temperature in longer time.