Document Type : Original Article
Author
Senior Res., Agr. Eng. Res. Inst., Agr. Res. Center, El-Dokki, Cairo, Egypt.
Abstract
The aim of this study was measuring and determination of the optical properties of maturity stages of orange fruits (Abo Sora variety) using visible light (VIS ) and invisible lights (UV and IR). Three light regions, ultraviolet (350 – 400 nm), visible light (400-700nm), and near infrared (700-1000 nm) wavelengths were used. Obtained results were summarized as follow: (a) Reflection intensities using ultraviolet light with wavelengths from 350 to 400 nm from orange fruit of maturity stages ranged between 173.8 and188.80 a.u. Meanwhile, absorption intensities ranged between 174.29 and188.80 a.u. , b) Reflection intensities of infrared wavelengths from 700 to 1000 nm from orange fruits of maturity stages ranged between 166.72 and 277.73 a.u. Meanwhile, absorption intensities were ranged between 172.01-290 a.u. Therefore, there are no big differences in reflection and absorption intensities values of ultraviolet and infrared wavelengths for different maturity stages of orange fruit, Therefore, measurements of reflection and absorption intensities using ultraviolet and infrared were negligible; c) The peak reflection intensities using visible light were found 1051.83, 1361.21, 1959.85, 2461.68, 3760.96 and 3610.12 a.u at wavelengths of 540, 545, 550, 560, 570, 580 nm, respectively. Meanwhile, the peak absorption intensities were found 598.12, 980.79, 1959.73, 2615.14, 3189.04 and 3840.15 a.u at wavelengths 545 , 550, 560, 570, 580, and 585 nm for green, light green , very light green and turning, yellow, and orange maturity stages of color orange fruits, respectively., e) It is possible to use of 540, 545, 550, 560, 570, 580 nm as a source of peak reflection, while using 545 , 550, 560, 570, 580, and 585 nm as a source of peak absorption for green, light green , very light green and turning, yellow, and orange maturity stages of color orange fruits, respectively, to detect maturity stages of orange fruits., and f) Using light spectrum with wavelengths from 540 to 585 nm is preferable in grading orange fruit as a source of reflection and absorption peaks during maturity stages and can automatically control the process.
Main Subjects
)
View on SCiNiTO