The Application Research Of Near Infrared Spectroscopy In Nondestructive Detection Of Nanjiang Jujubes Internal Quality

This study took Southern Xinjiang red jujube as the research object, and tested jujube water, total sugarand total acid based on near infrared spectral. Based on the technology spot investigation of non-destructivetesting in well-known industry, this paper discussed jujube sugar and acidity nondestructive testing factorsaffecting accuracy, red jujube model sample selection method and moisture content, total sugar and totalacid fast nondestructive testing of mathematical model, red jujube processing factory practical applicationetc. The main results in present study are listed below:(1) The factors that affect the red jujube spectrum are: geography, size, variety and gathering place,sample collection, collection and temperature, etc.; The optimize parameters in the instrument wasequipped with a reflectance post-dispersive optical configuration and an indium gallium arsenide (InGaAs)array (range4000–10000cm-1,8cm-1resolution) with32times of scanning for each acquired spectrum.The method of SPXY to choose correct sample was better than the KS and random method. The model ofmoisture and total sugar was established with joint interval partial least squares method and the geneticcombination of partial least squares method. The model of total acid was established with informationvariable elimination. Finally the standard deviation correction (RMSEC), the correction coefficient ofcorrelation (RC), the prediction to standard deviation (RMSEP) and correlation coefficient (RP) of junjujube moisture and ash model are1.1280and1.6266,0.9879and0.9880,3.1551and1.8779,0.9384and0.9765respectively. Jun jujube total sugar model (RMSEC) standard deviation correction, the correctioncoefficient of correlation (RC), the prediction to standard deviation (RMSEP) and correlation coefficient(RP) are0.9778,0.8510,0.9446, and1.3748, respectively. The mathematical models of total acid standarddeviation correction (RMSEC), the correction coefficient of correlation (RC), prediction to standarddeviation (RMSEP) and correlation coefficient (RP) are0.9216,0.0582,0.8778, and0.0582, respectively.(2) In jujube processing, The temperature hybrid model with5℃,15℃,35℃was established topredict the unknown sample standard deviation. The result is better than single temperature model;Compared to the temperature model, the temperature stability of the hybrid model, the reliability andaccuracy relative was greatly improved. The operation is simple, rapid, without damage to samples.(3) The near infrared spectrum of red jujube was acquired by Antaris Ⅱ FT-NIR and then transferredinto a portable near infrared spectrometer supNIR-1520spectrum through the model algorithm, thenmodeled. The results showed that the predictive results of the model before and after were same.This paper explored and testing the red jujube internal water, sugar and acidity method based on nearinfrared spectrum fast nondestructive and establishing the mathematical model of stable performance, areimportant theoretical significance and practical application value of the basic work.