Maximising the stability of anthocyanins and the physicochemical quality in pure blood orange juice using advanced Weibull-Log-Logistic modelling and ascorbic acid fortification during pasteurisation

Anthocyanins are natural pigments plentiful in Blood Orange Juice (BOJ), that give juice colour with highly beneficial nutrients. However, pasteurisation can affect anthocyanin stability and quality. This study aimed to investigate the effect of Ascorbic Acid Fortification (AAF) (100 ppm, “0.01%”) varying temperature/time pasteurisation (60 to 90 °C) on the kinetics of anthocyanins degradation and the physicochemical quality of pure BOJ. Anthocyanin content was determined using the pH-differential method. The degradation kinetics was well predicted using the Weibull model with optimized n values (fixed values) (0.824 ≤ Radj2 ≤ 0.952; 0.10 ≤ RMSE ≤0.01). Findings showed that AAF improved anthocyanins retention, but increased thermal sensitivity over time. Furthermore, the Log-Logistic model accurately explains temperature-dependent anthocyanin rate constants during pasteurisation for BOJ with and without added ascorbic acid (0.828 ≤ Radj2 ≤ 0.991; 0.0002 ≤ RMSE ≤0.0019). This study provides a novel approach for maximising pure BOJ pasteurisation parameters, using an advanced Weibull-Log-Logistic modelling approach and AAF.