The objective of this study was to predict the degradation kinetics of vitamin C in camu camu and naranjilla juices using accelerated storage tests. The juices were produced under controlled processing conditions, including physicochemical standardization, pasteurization, and hot filling into glass containers. They were then stored at 35, 45, and 55 °C for 21, 14, and 7 days, respectively. The vitamin C content was quantified using high-performance liquid chromatography, showing a progressive decrease depending on temperature. The kinetic data were fitted to zero-order and first-order models, as well as to the nonlinear Weibull model, the latter presenting the best statistical fit (R2 = 0.9678–0.9931) and adequately describing the nonlinear degradation behavior of vitamin C. Temperature dependence was modeled using the Arrhenius equation, allowing activation energy to be estimated and confirming temperature-dependent degradation behavior in both juices, with different thermal responses depending on the modeling approach. Likewise, shelf life (t80) was estimated using the Weibull model and showed a significant reduction with increasing storage temperature. Arrhenius-based shelf-life predictions suggested greater vitamin C retention in camu camu juice at lower storage temperatures, whereas naranjilla exhibited a more pronounced decrease as temperature increased. The physicochemical parameters (pH, acidity, and °Brix) showed moderate changes, maintaining the stability of the system during storage. The results confirm the applicability of the Weibull model to describe vitamin C degradation in complex matrices and highlight the importance of thermal control in the preservation of bioactive compounds in tropical juices.
Fernández-Rosillo et al. (Thu,) studied this question.