Physiological Quality And Respiratory Characteristics Of Psidium Guajava L. During Modified Atmosphere Storage

Guava （psidium guajava L.） belongs to Psidium in the Myrtaceae, which was originallyfrom tropical regions in America, and was introduced into China in the end of the17thcentury.This paper studied the modified atmosphere packaging of guava, studied physiological quality ofguava in modified atmosphere packaging and non-modified atmosphere packaging, comparedphysiological quality of guava in three gas concentrations, determined respiration rate of guavawith sealing system, and established three respiratory rate models and verified them. The mainresearch contents and conclusions are as follows:1. Comparing apperence （flesh firmness, chroma）, nutrients （reducing sugar, titratable acid, vitamin C）, peroxidase activity, putrefactive products （malondialdehyde）, and so on of guava in modified atmosphere and non-modified atmosphere packaging at12℃, the results showed that guava shelf-life in modified atmosphere packaging was extended by two times.2. Comparing apperence （flesh firmness, chroma）, nutrients （soluble solid content, reducing sugar, titratable acid）, peroxidase, malondialdehyde, and so on of guava in three gas concentrations （2%O2+5%CO₂+93%N2,4%O2+5%CO₂+91%N2,10%O2+5%CO₂+85%N2）, we discovered the storage quality of guava would be the best when atmosphere environment was4%O2+5%CO₂+91%N2.3. Determining the initial respiration rate of guava with sealing system at10℃,12℃,15℃,20℃and25℃, of which the respiratory data at10℃,15℃,20℃and25℃were used to establish respectively respiratory rate model based on chemical kinetics, enzyme kinetics and neural network, and the respiratory data at12℃were used to validate the models. By comparison of the model factors, we obtained the model based on neural network was the best respiration rate model of guava.