Study On Application Of Nonlinear Chemical Fingerprint In Authenticity Identification And Quality Evaluation Of Soya Sauce And Dairy Product

With the improvement of living standards and the progress of human civilization, more attention has been paid on the quality of life and the healthy diet by people. Therefore, the quality evaluation and authenticity identification of foods were more and more concerned by people. Soya sauce and dairy product are the foods of mass consumption in our daily life, and their quality and authenticity are also concerned by people. The hotspot of researches is the method for quick and scientific identification and evaluation of them. The nonlinear chemical fingerprint as a new technology is able quickly and scientifically to identify and evaluate the foods as complex systems. Therefore, both of the nonlinear chemical fingerprint technology and its application to identify and evaluate soya sauce and dairy product were deeply studied in this paper.The food security situation, the nonlinear chemistry fingerprint and its application, the introduction and development of the nonlinear chemical fingerprint technology were introduced in the first chapter of the paper.The principles of food nonlinear chemical fingerprint and its similarity calculation as well as the comparison of pattern recognition methods were discussed in the second chapter.In the third and forth chapters, the principles of food nonlinear chemical fingerprint and its similarity calculation methods were combined to identify different soya sauces and dairy products as well as evaluate their qualities. The results obtained from the experiments and data analysis have shown that:All the nonlinear chemical fingerprints of soya sauces and dairy products have very good characteristic, reproducibility and abundant quantifiable information, and could directly be used to identify and evaluate the soya sauces and dairy products. The result obtained by comparing with correlation coefficient, included angle cosine and Euclidean distance showed that, system similarity could best reflect the difference between the characteristics of the fingerprints of different soya sauces and dairy products. The system similarities of the fingerprints of the same brand of soya sauces and dairy products≥93.85%and≥94.36%, respectively, while those of the different brands of soya sauces and dairy products≤64.03%and≤85.71%, respectively, and the average accuracy rates to identify the authenticities of the soya sauces and dairy products by system similarity were99.33%and97.64%, respectively. The total content of effective components of soya sauces and dairy products have good linear relationships with the undulatory lives of the relevant fingerprints, and the relationships may be used to evaluate the qualities of soya sauce and dairy product. The methods for identifying the authenticity of soya sauce or dairy product by system similarity pattern and evaluating its quality by the relationships between the quantitative information and the total content of effective components of soya sauce or dairy product were putted forward.