Abstract:
In order to solve the problems such as poor stability and rapid precipitation of passion fruit juice, the influence of the different stabilizers on the stability of passion fruit juice was explored using the automatic stability analyzer based on the space and time resolved extinction profiles technology (STEP-Technology) in the current study. The sedimentation rate, the integral transmittance and transmission infrared spectrum were selected as the main indexes to determine the stabilizing effects of agar and/or sodium carboxymethyl cellulose (CMC-Na) on the passion fruit juice stability. Results showed that, addition of CMC-Na resulted smoother light extinction curves compared to agar, indicating CMC-Na might exert better stabilizing effects when single stabilizer was used. The optimal stabilizing effect being obtained by addition of CMC-Na at 0.30%~0.35% with the lowest settlement rates ((0.0209±0.0003) %/s and (0.0181±0.0002) %/s, respectively) being recorded. When these two stabilizers were applied simultaneously, it was found that increase in CMC-Na and decrease in agar led to the smoother light extinction curves and enhanced stability of juice. The optimal stability were reached by addition of 0.35% CMC-Na+0.15% agar and 0.30% CMC-Na+0.20% agar, which showed the lowest settlement rates ((0.0231±0.0004) %/s and (0.0209±0.0004) %/s, respectively). These findings could provide a scientific basis for the development of passion fruit juice with improved stability.