Controlling cathepsin B activity in Jinhua ham through multifactorial analysis and modeling of temperature, pH and salt content

The activity of cathepsin B in Jinhua ham was affected by various processing parameters, which were investigated and quantified using a multi-layer artificial neural network (ANN). The key factors that influence ham quality are processing temperature, pH, and sodium chloride content. The study discussed the univariate analysis and multivariate interactions between two or three factors. The established ANN model was used for further investigation, and the actual enzyme activity of cathepsin B was characterized. The results showed that high temperature (greater than 60 °C) and an alkaline environment or the addition of Na + cation significantly reduced the enzyme activity (p < 0.05). The optimal conditions for protease activity were found to be at 40 °C and pH 6.0. The enzyme was found to be unstable at a temperature of 20 °C or pH 6.5–7.0 in the presence of NaCl, indicating significant interactions between temperature, pH value and NaCl content (p < 0.01). Furthermore, the ANN model showed good match between true and predicted values. The correlation coefficient was 0.98468, and the model provided supplementary information about the effect of NaCl on cathepsin B activity within 0.4M–0.6M. The findings could be useful in Jinhua ham production and the study of the structure-activity relationship of cathepsin B.