Research on vitamin C loss prediction model of extruded kiwifruit pork jerky

Abstract

[Objective] In order to explore the loss pattern of VC in kiwifruit pork jerky by twin-screw extrusion and solve the "black box" problem of nutrient loss during the extrusion process. [Methods] In this paper, a twin-screw extruder was used to produce kiwifruit pork jerky, and the VC content of the material before and after extrusion was determined by high performance liquid chromatography, and the Mean Residence Time （MRT） was used as the reaction time of the material in the barrel, and the VC loss rate under different extrusion conditions was dynamically analyzed. [Results] Increasing the temperature and moisture content of the barrel, decreasing the screw speed, and increasing the amount of dried fruit added during the extrusion process will increase the VC loss rate of the extruded material. The variation pattern of MRT and VC loss rate is basically consistent. Dynamic analysis shows that VC loss during the extrusion process follows a first-order dynamic model, and the VC loss rate constant is between 0.003 54 and 0.006 05 s-1. [Conclusion] MRT is an important factor affecting the variation of VC loss rate. A predictive model for VC loss rate can be obtained through multiple regression analysis, which can achieve reasonable prediction of the variation pattern of VC loss rate under different conditions and reduce production costs.

Keywords

• twin-screw extrusion
• kiwifruit
• pork
• the mean residence time
• vitamin c
• kinetic analysis