Method for rapidly detecting content of amino acid nitrogen and total acids by using mid-infrared spectrum

Abstract

The invention relates to the field of rapid food detection and particularly relates to a method for rapidly detecting the content of amino acid nitrogen and total acids by using a mid-infrared spectrum. The method comprises the following steps: (1) selecting multiple parts of soy sauce with different contents of amino acid nitrogen and total acids; (2) determining the content of the amino acid nitrogen in each soy sauce sample; (3) determining the content of the total acids in each soy sauce sample; (4) performing spectral collection by using a mid-infrared spectrometer; (5) establishing a quantitative determination model for the amino acid nitrogen and total acids, wherein bands selected by the quantitative determination model are all in a range from 1697.05cm<-1> to 1369.21cm<-1>; (6) performing spectral collection on to-be-detected soy sauce samples by using the mid-infrared spectrometer, and comparing the spectrum of the soy sauce sample with the quantitative determination model, so as to obtain the content of the amino acid nitrogen and total acids. According to the method, only the mid-infrared spectrum in the sample needs to be collected once, and when the spectrum is inputinto the model, the content of the amino acid nitrogen and total acids can be rapidly and simultaneously detected.

Description

technical field [0001] The invention relates to the field of rapid detection of food, in particular to a method for rapid detection of amino acid nitrogen and total acid content in soy sauce by using mid-infrared spectroscopy. Background technique [0002] Amino acid nitrogen is one of the most important indicators in soy sauce. The quality grade of soy sauce can be determined according to the amino acid content. The higher the amino peptide content, the better the quality of soy sauce. Total acid refers to the amount of all organic acids in soy sauce converted into lactic acid, which can reflect the degree of sourness of soy sauce and the level of fermentation technology of soy sauce. However, at present, whether it is the determination of amino acid nitrogen content in soy sauce by double-indicator formaldehyde titration method and potentiometric titration method, or the determination of total acid content in soy sauce by acid-base titration method, not only the experiment...

AI Technical Summary

Problems solved by technology

However, at present, whether it is the determination of amino acid nitrogen content in soy sauce by double-indicator formaldehyde titration method and potentiometric titration method, or the determination of total acid content in soy sauce by acid-base titration method, not only the experimental operation is cumbersome, but even a large amount of toxic reagents similar to formaldehyde are required, which is harmful to the body. dangerous

[0003] Infrared spectral analysis technology has the advantages of fast analysis speed, high detection efficiency, easy operation, no need for pretreatment and no pollution, it can detect multiple indicators of samples at the same time, and quickly complete the monitoring of large-scale sample production processes. , cosmetics, petrochemical and many other industries have been applied, but most of them are near-infrared, and there are relatively few reports on rapid detection based on mid-infrared.

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