Study On Application Of Stable Isotope Technique In Origin Tracing Of Mutton

With an increasing awareness of safety and health,the requirements for food safety are becoming higher and higher.Mutton,as a type of meat product which is low in fat and high in protein,brings a huge market potential.It is important to identify the Ningxia tan sheep which is a geographical indication agricultural product in China.In recent years,due to poor management of the geographical indication agricultural products,counterfeit and inferior products have emerged endlessly,which has seriously damaged the rights and interests of consumers.Therefore,it is urgent to establish an accurate and effective method to identify Tan sheep.At present,the traceability system of agricultural products is established mainly through the determination of the content and composition of fatty acid elements and the detection technologies of ICP-MS and stable isotopes.Stable isotope mass spectrometry has been used in geological exploration and environmental science for many years because of its obvious advantages.In recent years,with the progress of stable isotope mass spectrometry and the development of mass spectrometry,stable isotope mass spectrometry has been applied to the study of the traceability of animal-derived agricultural products.This article selects the mutton and sheep bone samples from four origins of the Ningxia Tibet mutton,black sheep in Gansu province,sheep in New Zealand and Anhui native goat.Geographical origins of the mutton samples can be identified effectively by using the stable isotope mass spectrometry to determine the?¹³C,?¹⁵N,?²H and?¹⁸O value of the mutton in the butterfly steak part and the SPSS 22.0 software,SIMCA 14.1 software and ORIGIN software to analyze the data.The main results are as follows:1.59 experimental mutton samples were selected from five different parts of the hind legs,chest fork,pork ribs,neck and abdomen on 12 black native goats in Gansu province.A sample preparation method with freeze-dried,degreasing and flouring was established and the stable isotope mass spectrometry was applied to determine the?¹³C,?¹⁵N,?²H and?¹⁸O of five different parts on Gansu province native goat.PLS-DA was used to analyze the?¹³C,?¹⁵N,?²H and?¹⁸O of different parts and the cross validation results was 44.07%.SPSS 22.0 software was used to conduct the Duncan statistical analysis and variance analysis for the sample data,and we discovered the least significant difference was found in the butterfly steak part of the mutton,so in the next tests,the mutton sample from the butterfly steak part was selected as the detection samples.2.78 mutton of butterfly steaks parts from four origins of Ningxia Tibet sheep,black sheep in Gansu province,sheep in New Zealand and Anhui native sheep was selected as experimental samples.We established sample preparation methods combining freeze-dried,degreasing with flouring as a whole and applied the stable isotope mass spectrometry to determine the?¹³C,?¹⁵N,?²H and?¹⁸O value of mutton of the butterfly steaks part from four different regions.Cross validation results was 97.26%using PLS-DA to analyze the?¹³C,?¹⁵N,?²H and?¹⁸O of the mutton of butterfly steak parts from four different regions.SPSS 22.0 software was used to conduct the Duncan statistical analysis and variance analysis for the sample data,and we found that the significant difference was obvious in the mutton samples of the butterfly steak part,so the retrospective study to the mutton sold on markets can be conducted using the mutton samples from the butterfly steak part.3.To further study the?¹³C and?¹⁵N trace ability in the whole bone meal,skimmed sheep bone meal,collagen of the sheep bones in the butterfly steak part from four origins:Ningxia Tibet mutton,black sheep in Gansu province,sheep in New Zealand and Anhui native goat.Therefore,the sheep bones of 78 mutton of butterfly steak part from four different regions were removed and a total of 234 samples of total bone meal,defatted bone meal,and bone collagen were extracted as experimental samples,whose?¹³C and?¹⁵N were measured by stable isotope mass spectrometry.The?¹³C value and?¹⁵N value in different parts were analyzed by Duncan statistics using SPSS 22.0 software,and the analysis of variance was performed.It was found that the significant difference in defatted bone meal of butterfly steak part in sheep's bones from four different regions was obvious,and it was followed by collagen and defatted bone meal.The original verification result of whole bone meal was 70.50%,and the cross-validation result was 66.70%;the original verification result of defatted bone meal was 64.10%,and the cross-validation result was 68.20%;the original verification result of bone collagen was 69.20%,and the cross-validation result is 66.70%.Simply looking at the measurement of?¹³C and?¹⁵N values,the original verification result of the mutton sample of the butterfly steak part was 84.60%,and the cross-validation result was 82.10%.From this,we can know that the identification rate of carbon and nitrogen stable isotope ratios of the three substances:the whole bone meal,defatted bone meal and bone collagen in the mutton bone of the butterfly steak part is lower than that of the mutton samples of the butterfly steak part.