Soluble Solids Content and pH Prediction and Maturity Discrimination of Lychee Fruits Using Visible and Near Infrared Hyperspectral Imaging

Abstract

Hyperspectral imaging (HSI) technique has shown promise as a rapid and nondestructive tool to evaluate various internal quality attributes of fruits and vegetables. The objective of this study was to investigate the nondestructive prediction of soluble solids content (SSC) and pH of lychees and maturity discrimination. Two hyperspectral imaging systems of visible/short-wave near infrared range (600-1000 nm, Spectral Set I) and long-wave near infrared range (1000-2500 nm, Spectral Set II) were employed. Results showed that Spectral Set II (SSC: r p =0.877, RMSEP=0.911°Brix; pH: r p =0.745, RMSEP=0.291) performed better than Spectral Set I (SSC: r p =0.790, RMSEP=1.279°Brix; pH: r p =0.701, RMSEP=0.308) for the internal quality prediction of litchi and maturity discrimination. The partial least square discriminant analysis (PSL-DA) model had a discrimination rate of 90.63 % for Spectral Set I and 96.88 % for Spectral Set II. β-Coefficients of partial least squares regression (PLSR) models were used to choose optimal wavelengths for quality predictions. The performance of optimized PLSR in both spectral sets were comparable to the models developed using the whole spectral range.

Determination of pesticide residual levels in strawberry (Fragaria) by near‐infrared spectroscopy

“…(b) with bands highlighted. These vibrations were identified according to the literature . Accordingly, the peak reaching a maximum at 5240 cm −1 shows the first overtone of the O─H group.…”

“…, with the maximum wavelengths of the absorption peaks highlighted. These peaks were identified according to the literature . Accordingly, the absorption at 10 433 cm −1 corresponded to O─H bonds from water and carbohydrate.…”

Comparison of various chemometric analysis for rapid prediction of thiobarbituric acid reactive substances in rainbow trout fillets by hyperspectral imaging technique

“…Although TBARS test shows relatively exact result, this method is time‐, labor‐, and chemical solvent‐consuming and destructive. Hyperspectral imaging (HSI) techniqueby integrating the advantages of two important nondestructive methods, spectroscopy and computer vision, into one system has become a promising tool to determine and evaluate food quality and safety in a nondestructive and rapid manner (ElMasry, Barbin, Sun, & Allen, ; Kamal & Karoui, ; Naganathan et al, ; Pu, Liu, Wang, & Sun, ; Wang et al, ; Wu & Sun, , ; Xiong, Sun, Xie, Han, & Wang, ). In this regard, several exploratory studies were established about using HSI coupled with the appropriate linear and/or nonlinear chemometric multivariate analyses to evaluate quality and safety of fish and other seafood based on various important parameters such as sensory parameters (Cheng & Sun, ; Ma, Sun, Qu, & Pu, ; Wu, Sun, & He, ), TVB‐N (Cheng, Sun, & Wei, ; Cheng, Sun, Zeng, & Pu, ), TVC (Cheng & Sun, ; Khoshnoudi‐Nia, Moosavi‐Nasab, Nassiri, & Azimifar, ; Wu & Sun, ), K ‐value (Cheng, Sun, Pu, & Zhu, ; Cheng et al, ), and TBARS (Cheng, Sun, Pu, Wang, & Chen, ; Cheng et al, ; Xu et al, ).…”

Black Heart Detection in White Radish by Hyperspectral Transmittance Imaging Combined with Chemometric Analysis and a Successive Projections Algorithm

“…Many nondestructive sensing techniques, like spectroscopy, acoustics, and X-ray imaging, have been reported for internal quality inspection of fruits and vegetables [3][4][5][6]. Among these methods, substantial work has focused on using near-infrared spectroscopy (NIRS) to inspect internal defects, like brown core in Chinese pears [7], brown heart in Braeburn apples [8,9] and in Conference pears [10], translucent flesh disorder in mangosteen [11], black air-cavity defects in Japanese radishes [12], and mealiness in apples [13].…”

“…Huang and Lu [23] carried out apple mealiness detection using hyperspectral scattering imaging. Furthermore, quality attributes like soluble solids content, pH, and firmness can be successfully predicted by hyperspectral imaging [6,[24][25][26]. The technique, however, has so far been largely limited to laboratory or benchtop applications because of the cost, huge volume of data, and computing requirements.…”