Related Experiment Video
Updated: May 20, 2026

Fruit Volatile Analysis Using an Electronic Nose
Published on: March 30, 2012
[Temperature compensation for portable Vis/NIR spectrometer measurement of apple fruit soluble solids contents]
Jia-hua Wang1, Shu-ye Qi, Zhi-hui Tang
1School of Food Science & Engineering, Xuchang University, Xuchang 461000, China. w.jiahua@163.com
Abstract:
Visible (Vis)/near infrared (NIR) spectroscopy has been used successfully to measure soluble solids content (SSC) in fruit. However, for practical implementation, the NIR technique needs to be able to compensate for fruit temperature fluctuations, as it was observed that the sample temperature affects the NIR spectrum. A portable Vis/NIR spectrometer was used to collect diffused transmittance spectra of apples at different temperatures (0-30 degrees C). The spectral data of apple at 20 degrees C was used to develop a norm partial least squares (PLS) model. Slope/bias technique was found to well suits to control the accuracy of the calibration model for SSC concerning temperature fluctuations. The correctional PLS models were used to predict the SSC of apple at 0, 10 and 30 degrees C, respectively. The correctional method was found to perform well with Q values of 0.810, 0.822 and 0.802, respectively. When no precautions are taken, the Q value on the SSC may be as small as 0.525-0.680. The results obtained highlight the potential of portable Vis/NIR instruments for assessing internal quality of fruits on site under varying weather conditions.
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