Abstract:
This research aims to prepare red cabbage extracts and enhance their stability using vacuum freeze-dried technique and copigmentation with 1.25% guar gum. Red cabbage was extracted using a solvent alongside ultrasonic-assisted extraction and evaporate off the solvent, yielding a crude anthocyanin extract of 57.67±6.81% for freeze-dried and 59.26±5.13% for copigmentation combined with freeze-dried. The total anthocyanin content of the freeze-dried red cabbage extract was 79.44±0.06 mg/L, while that of the copigmentation combined freeze-dried extract was 87.72±0.23 mg/L. For thermal stability testing at 40, 60, and 80°C over 120 minutes (measured every 10 minutes), the copigmentation and freeze-dried red cabbage anthocyanin extract exhibited the highest stability at 40°C, retaining 82.95 mg/L of total anthocyanins (only a 4.92% reduction). At 80°C after 120 minutes, this extract showed the highest degradation rate (14.04%), with a remaining anthocyanin content of 73.50 mg/L. These findings correlated with color measurements under four conditions. In the dark storage condition, the total color difference (∆E*) was only 2.25, which was undetectable by the visual observation.