The Research of Nondestructive Testing of Apple Acidity Based on Near Infrared Spectroscopy
the detection of the apple internal acidity using near infrared reflection spectroscopy is researched in this paper. This paper also elaborates the principle of partial least squares (PLS), and models spectral data by using the partial least squares method. Focuses on the comparison of the single points measurement and multiple points measurement in the Apple’s maximum diameter measurements, gets the following conclusions: a single point spectral scans can not accurately predict the internal acidity of the apple, the experimental precision of the multi-points measurement is higher then the single points measurement. The authors suggest that the measurement of average spectral values by multi-fiber optic probe should be used for the detection of the apple acidity.