Growth kinetics model of coliform under different storage temperatures of pitaya pulp and shelf-life prediction

In order to explore the suitable storage temperature,take red pitaya pulp as the material and storage experiment was carried out at 4,10 and 25℃ after instantaneous sterilization. The growth kinetics model and the shelf life prediction model were established. Total sugar,titratable acid,anthocyanin content,total bacteria and coliform bacteria of pitaya pulp during the storage at different temperature were studied and analysis of physical and chemical indicators,Gompertz model were used to establish the prediction model for shelf-life of pitaya pulp. The results showed that the contents of total sugar and anthocyanin were decreased after the temperature was higher than that of the control. The content of titratable acid decreased first and then increased,and the total number of coliforms and total bacteria increased gradually,compared with different temperature,storage temperature at 4℃ could reduce the physical and chemical quality,The establishment of coliform bacteria model,the R² value of more than 0.96 and they all fluctuate around zero.The average number of specific spoilage microorganisms was 4.28 lg(CFU/mL)at the end of shelf-life. Conclusion:The suitable storage temperature for the pitaya pulp was 4℃.The model for describing the growth of coliform bacteria is credible,Therefore,the prediction model for the shelf-life were validated.