Determination of lycopene and beta-carotene content in tomato fruits and related products: Comparison of FT-Raman, ATR-IR, and NIR spectroscopy.
Tomatoes and various products derived from thermally processed tomatoes are major sources of lycopene, but apart from this micronutrient, other carotenoids such as beta-carotene also are present in the fruit. They occur in tomato fruits and various tomato products in amounts of 2.62-629.00 (lycopene) and 0.23-2.83 mg/100 g (beta-carotene). Standard methods for determining the carotenoid content require the extraction of the analyte as well as other cleanup steps. In this work, FT-Raman, ATR-IR, and NIR spectroscopy are applied in order to establish new, fast, and nondestructive calibration methods for quantification of lycopene and beta-carotene content in tomato fruits and related products. The best prediction quality was achieved using a model based on IR spectroscopy (R2 = 0.98 and 0.97, SECV = 33.20 and 0.16 for lycopene and beta-carotene, respectively). In spite of the fact that Raman spectra of tomato products show characteristic key bands of the investigated carotenoids, this method gives slightly lower reliability (R2 = 0.91 and 0.89, SECV = 74.34 and 0.34 for lycopene and beta-carotene, respectively). NIR spectroscopy, which has been used for quantification purposes in the agricultural sector for several decades, in this study shows the worse prediction quality (R2 = 0.85 and 0.80, SECV = 91.19 and 0.41 for lycopene and beta-carotene, respectively).
Baranska
M
M
Federal Centre for Breeding Research on Cultivated Plants, Institute of Plant Analysis, Erwin-Baur-Str. 27, D-06484 Quedlinburg, Germany.
Schütze
W
W
Schulz
H
H
D002338:Carotenoids / Q000032:analysis*; D000077276:Lycopene; D018551:Solanum lycopersicum / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D019265:Spectroscopy, Near-Infrared; D013059:Spectrum Analysis, Raman; D013997:Time Factors; D019207:beta Carotene / Q000032:analysis*
D019207:beta Carotene; D002338:Carotenoids; D000077276:Lycopene