Studies of tropical fruit ripening using three different spectroscopic techniques

Abstract

Abstract. We present a noninvasive method to study fruit ripening. The method is based on the combination of reflectance and fluorescence spectroscopies, as well as gas in scattering media absorption spectroscopy (GASMAS). Chlorophyll and oxygen are two of the most important constituents in the fruit ripening process. Reflectance and fluorescence spectroscopies were used to quantify the changes of chlorophyll and other chromophores. GASMAS, based on tunable diode laser absorption spectroscopy, was used to measure free molecular oxygen in the fruit tissue at 760 nm, based on the fact that the free gases have much narrower spectral imprints than those of solid materials. The fruit maturation and ripening processes can be followed by studying the changes of chlorophyll and oxygen contents with these three techniques. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Gas exchange in fruits related to skin condition and fruit ripening studied with diode laser spectroscopy

“…The present work studying the gas dynamics greatly extends our earlier GASMAS studies of static gas behavior, as reported in Ref. 29, and also connects to the techniques of direct application of an artificial "skin" on the fruits, a surface coating. 39…”

“…Although there have been several experimental techniques for gas studies related to fruits, there is clearly room for additional and improved methods. A nonintrusive, compact, in-situ, and easily implemented spectroscopic technique-gas in scattering media absorption spectroscopy (GASMAS)-was introduced in 2001, 22 and since then this technique has been developed into different applications, 23,24 such as for wood, [25][26][27] fruits, 5,28,29 food packaging, 30,31 and medical diagnostics. 32,33 This technique employs a narrowband tunable diode laser to measure gases in pores and cavities in condensed-matter matrices.…”

Nondestructive Evaluation of Apple Fruit Quality by Frequency-Domain Diffuse Reflectance Spectroscopy: Variations in Apple Skin and Flesh

“…Numerous studies on measuring the optical properties of fruits using advanced optical techniques that are mainly based on the radiative transfer theory have been conducted [6][7][8]. These optical methods have been widely applied for the noninvasive characterization of tissue properties through measurements of light-tissue interaction phenomena such as reflectance, propagation, and attenuation [7,9]. Among the various optical methods, diffuse reflectance spectroscopy (DRS) is useful for monitoring apple quality.…”

Investigating Maturity State and Internal Properties of Fruits Using Non-destructive Techniques-a Review

“…From the testing of each fruit, it was found that the reflectance and fluorescent spectra were sensitive to chlorophyll content. Hence the technique could be an estimator of chlorophyll changes in the fruit ripening process [11]. The reflectance property of NIR spectroscopy was tested with different cultivars of apples, where it was found that the water content of apples decreases with increased shelf-life of the fruit [12].…”