Effect Of Swelling Agent Treatment On Grape Fruit Quality And Rapid Recognition Of Electronic Nose

With the improvement of living standards,people pay more and more attention to food quality and safety.Bulking agent is a plant growth regulator,which can promote plant cell division,cell expansion and improve crop yield.In grape production,using bulking agent treatment can promote the increase of fruit grain,so as to effectively improve grape yield.However,under the action of swelling agent,the fruit quality will also be affected,and the residue of swelling agent exceeding the standard will endanger human health.Therefore,it is of great significance to actively explore some methods that can effectively detect whether grape fruits are treated with bulking agent,which is conducive to promoting the healthy development of fruit market.Due to the thinning of grape peel and the change of internal nutritional components of grape fruit under the action of expander,the volatile gas composition and content of grape fruit will also be different from that of naturally mature fruit(without expander treatment).Based on this,this study discussed the effect of swelling agent treatment on grape fruit quality,and used gas sensing technology(electronic nose technology)to detect the odor information of grape fruit treated with different concentrations of swelling agent,and used four feature extraction methods to analyze through four pattern recognition algorithms,in order to explore an accurate and efficient recognition model and provide a scientific basis for the rapid recognition of grape swelling fruit.The main results are as follows:1.Effect of swelling agent treatment on fruit quality.In the development stage of grape fruit,the content of soluble sugar and soluble solid decreased and the content of titratable acid increased when treated with low concentration swelling agent(CPPU concentration of 2mg / L),but the difference was not significant compared with the fruit without swelling treatment(natural maturity)(P > 0.05);When the concentration of CPPU reached 4mg / L,the content of soluble sugar and soluble solid decreased significantly,and the content of titratable acid increased significantly.Compared with natural mature fruits,the difference reached a significant level(P < 0.05),but it had little effect on the content of soluble protein and vitamin C;When the concentration of CPPU reached 6mg / L,the contents of soluble sugar,soluble solid,soluble protein and vitamin C in fruits decreased significantly compared with naturally mature fruits,while the content of titratable acid increased significantly,and the difference between fruits and naturally mature fruits reached a significant level(P < 0.05).2.Recognition research of electronic nose technology in Grape Fruit Swelling detection.The electronic nose detection system was used to collect the odor information of naturally mature fruits and fruits treated with bulking agent,and the eigenvalue extraction and data processing of the collected electronic nose response signals were carried out.Four eigenvalues(max,mean,IV,WT)are extracted and identified by using linear discriminant analysis(LDA),back propagation neural network(BPNN),support vector machine(SVM)and random forest(RF)based on R language software.The results show that the effect of linear discriminant analysis(LDA)recognition algorithm is not ideal,and the data overlap in the classification map is more,so the samples can not be accurately distinguished.By comparing the accuracy of the combined recognition pattern of different eigenvalues and three nonlinear algorithms(BPNN,SVM and RF),it shows that the recognition pattern constructed based on the eigenvalues extracted by wavelet transform(WT)and support vector machine(SVM)algorithm has high accuracy,and the accuracy of its test set is 96.88%.This study analyzed the effect of swelling agent treatment on grape fruit quality,and established a recognition model based on electronic nose detection technology to quickly identify whether grape fruit has been treated with swelling agent.The research results can provide a reference basis for the quality and safety detection of grape fruit.