DETERMINATION OF BRIX VALUE AND ACIDITY IN PINEAPPLE FRUITS BY NEAR INFRARED SPECTROSCOPY

T. Shiina, T. Ijiri, I. Matsuda, T. Sato, S. Kawano, N. Ohoshiro
The potential of near infrared (NIR) absorbance by fruit tissue in an integrating sphere to nondestructively evaluate pineapple (Ananas comosus (L.) Merr.) fruit quality was examined. Pineapples used in this investigation were cultivated in Okinawa prefecture, on the southernmost island in Japan. The fruits were harvested at five different maturity stages in both 1990 and 1991. A NIR spectrophotometer and a specially designed fruit drawer were used to generate spectral data in the wavelength region from 700 to 2500 nm. Sliced samples approximately 3 cm thick were removed from the outer layer of the intact fruit and used for NIR measurement. The samples were taken from the upper, middle, and lower parts of each fruit. NIR measurements were made on the skin-side and the flesh-side of the sliced samples. As a reference, Brix and acidity were measured by a sugar-acidity analyzer, which consisted of a refractometer and electrical conductivity meter. Where the Brix value was estimated by NIR measurement on the skin-side, a multiple correlation coefficient of 0.88 with a bias-corrected standard error of prediction (SEP) of 1.29 °Brix between the estimated and actual values was obtained. The data suggest that near infrared spectroscopy (NIRS) has a potential for determining the Brix value of intact pineapple.
Shiina, T., Ijiri, T., Matsuda, I., Sato, T., Kawano, S. and Ohoshiro, N. (1993). DETERMINATION OF BRIX VALUE AND ACIDITY IN PINEAPPLE FRUITS BY NEAR INFRARED SPECTROSCOPY. Acta Hortic. 334, 261-272
DOI: 10.17660/ActaHortic.1993.334.27
https://doi.org/10.17660/ActaHortic.1993.334.27

Acta Horticulturae