The Research On Assessment Methods Of Table Grapes’ Logistics Quality Safety

Table grapes occupy an important position in the fruit consumption of residents in China, which are also a kind of major consumption fruits in the world. As berry fruits, table grapes are perishable and usually need to get through a multi-stage logistics process from the harvest to final consuming. Therefore, study about table grape logistics safety is of practical significance.In this work, we analyzed the characteristics of table grape logistics and the formation mechanism of the logistics safety based on field research and literature summary, and carried out studies on the key elements of the logistics safety formation mechanism. Assessment method of table grapes’ logistics quality safety was studied based on the quantitative analysis of the table grapes’ quality decay; the influence of constant concentrations of SO2 was studied; the methods based on nondestructive testing technology were studied with the application of near-infrared detecting and odor recognition; table grapes’ logistics quality safety control platform was designed based on the systematic analysis of the informatization requirements of table grapes’ logistics quality safety control. The main conclusions are as follows:(1) In this work, surface mold growth is the key limiting factor of table grapes’ logistics quality safety, the determination coefficient of the mold growth dynamics model built in this work is more than 0.9, in reliability assessment, the deviation value of the accuracy factor is less than 0.2, which show that the method based on mold growth kinetics could be used in the quality evolution prediction and logistics quality safety assessment of table grapes. Moreover, the dominating spoilage organism could also be Penicillium besides Botrytis mold in the quality decay, and its growth could be instability.(2) Using SO2 to control the growth of the mold, texture change and brown stain would become the key limiting factors of table grapes’ logistics quality safety, which could be modeled based on one order reaction model and zero order reaction model respectively, the determination coefficients are more 0.8, the method based on chemical kinetics could be used in the assessment under corresponding conditions. In cold chain logistics, SO2 with a stable concentration of 10ppm could effectively control the microbial growth on the skin of table grapes, but at room temperature, it should be 20 ppm.(3) The determination coefficient of the texture change nondestructive testing model built based on near infrared spectrum is more than 0.93, and the prediction accuracy in cross-validation is 0.81, which show that the method based on the combination of near infrared spectrum testing and the textural change kinetics model could be used for the assessment. At 0℃, after the sensor array optimization, the determination coefficient of the freshness shelf-life equivalent nondestructive testing model based on 4 gas sensors is more than 0.8, corresponding method could be used in the assessment based on odor recognition. Moreover, the modeling at room temperature should consider the influence of the concentration of SO2.(4) Based on the informatization requirement analysis of table grapes logistics safety control and related technology application testing, the integration of internet technology, GPRS technology and SMS warning technology could be used to improve the information management efficiency of table grapes logistics safety control and ensure the effectiveness of the assessment.