Application Of Rapid Evaporative Ionization Mass Spectrometry In The Identification Of Olive Oil Adulteration And Gelatin Donkey Hide Authentication

With the development of modern food industry,food adulteration driven by economic benefits occurs frequently.The complex and complicated problem of food adulteration and identification is in urgent need of fast,simple,highly sensitive and selective detection technology.Rapid evaporative ionization mass spectrometry(REIMS)is an emerging ambient mass spectrometry that requires little sample preparation and can directly analyze samples of different physical forms such as liquids,semi-solids or solids.It is easy to operate and fast to analyze,and is suitable for the detection of high-throughput samples.Combined with multivariate statistical methods,it shows great potential in the rapid identification of adulteration of food and raw materialsAccording to the actual,the olive oil and gelatin donkey hide that were easily adulterated in food were selected as the research objects.Combining REIMS and multivariate statistical analysis models,a rapid analysis method for the identification of olive oil and gelatin donkey hide was established respectively.The main contents include:1.Research on the application of REIMS technology in the identification of olive oil.Due to the non-conductive properties of olive oil,an innovative soldering iron replaced the REIMS smart scalpel i Knife as a sample collection tool.By collecting REIMS information of virgin olive oil,blended olive oil,sunflower oil,soybean oil,peanut oil,colza oil and corn oil,a qualitative and quantitative prediction model of virgin olive oil was established by using PCA-LDA and PLS analysis methods.The results showed that PCA-LDA model could distinguish virgin olive oil from blended olive oil and other vegetable oils,with the accuracy of cross-validation was 99.29%.Secondly,the model can be used to distinguished virgin olive oil of different adulteration levels effectively,and it showed a certain linear with the amount of adulteration increased,the minimum detection limit can be up to 5%.In addition,the PLS quantitative prediction model can be used to predict the adulteration content of other cheap vegetable oils in virgin olive oil samples.2.Research on the application of REIMS technology in the identification of gelatin donkey hide.By collecting REIMS information of donkey hide,mule hide and horse hide,PCA-LDA and OPLS-DA analysis methods were used as the identification models of different parts of donkey hide,donkey samples and other samples.The results showed that the use of PCA-LDA supervised model can be used to distinguish the four parts of donkey hide samples,and the accuracy of cross-validation can reach to 97.6%,but the accuracy of real-time recognition was low;The donkey samples from the four parts were placed at the same level as those from other hide included mule hide and horse hide,and all the samples were divided into two groups: donkey hide group and non-donkey hide group.The results showed that by simplifying the model,the donkey samples and other samples can be clustered and distinguished well.The accuracy of cross-validation and real-time recognition can reach 100%,which achieved fast and accurate authentication.