Nondestructive determination of sugar content in 'Danshaku' potato (Solanum tuberosum L.) by near infrared spectroscopy
2000
Yaptenco, K.F. (Tokyo Univ. of Agriculture (Japan)) | Suzuki, T. | Kawakami, S. | Sato, H. | Takano, K. | Kozima, T.T.
Near infrared (NIR) spectroscopy was evaluated as a nondestructive method of predicting sugars in 'Danshaku' potatoes. Tubers were stored at 2 and 10 degrees C for 4 weeks; samples were taken weekly and scanned at 400-1,100 nm. Cortical tissue from scanned areas was extracted and sucrose, glucose and fructose levels were determined by high performance liquid chromatography. Statistical analysis of NIR spectra by partial least squares (PLS) regression showed significant correlations between second derivative spectra and glucose and fructose levels (either individually or as reducing sugars). The best PLS regression model was for glucose, and used 6 factors with a correlation coefficient of 0.95 and standard error of calibration of 1.71 mg/g fresh weight. Weight spectra of these sugars correlated with optical spectra at 914 nm where sugar absorption occurs. HPLC-analyzed and NIR-estimated sugar levels of a separate prediction set were not significantly different for glucose, fructose, and reducing sugars (alpha=5%). However, at low sugar levels, more precise calibration models are needed to detect potatoes suitable for processing. With further refinement of the models, NIR spectroscopy could be used for rapid nondestructive testing of tubers prior to processing
Показать больше [+] Меньше [-]