Effect of Raman exposure time on the quantitative and discriminant analyses of carotenoid concentrations in intact tomatoes

Risa Hara; Mika Ishigaki; Yukihiro Ozaki; Tofael Ahamed; Ryozo Noguchi; Aiko Miyamoto; Takuma Genkawa

doi:10.1016/j.foodchem.2021.129896

Effect of Raman exposure time on the quantitative and discriminant analyses of carotenoid concentrations in intact tomatoes

Food Chem. 2021 Oct 30:360:129896. doi: 10.1016/j.foodchem.2021.129896. Epub 2021 Apr 26.

Authors

Risa Hara¹, Mika Ishigaki², Yukihiro Ozaki³, Tofael Ahamed⁴, Ryozo Noguchi⁵, Aiko Miyamoto⁶, Takuma Genkawa⁷

Affiliations

¹ Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Research and Development Department, Yokogawa Electronic Corporation, 2-9-32, Nakacho, Musashino, Tokyo 180-8750, Japan. Electronic address: hara.risa.rw@alumni.tsukuba.ac.jp.
² Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan. Electronic address: ishigaki@life.shimane-u.ac.jp.
³ School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan. Electronic address: ozaki@kwansei.ac.jp.
⁴ Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan. Electronic address: tofael.ahamed.gp@u.tsukuba.ac.jp.
⁵ Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan. Electronic address: noguchi.ryozo.gm@u.tsukuba.ac.jp.
⁶ Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Institute of Food Research, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8602, Japan. Electronic address: miyamotoa729@affrc.go.jp.
⁷ Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Institute of Food Research, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8602, Japan. Electronic address: genkawat748@affrc.go.jp.

PMID: 33989876
DOI: 10.1016/j.foodchem.2021.129896

Abstract

The significant worldwide expansion of the health food market, which includes functional fruits and vegetables, requires a simple and rapid analytical method for the on-site analysis of functional components, such as carotenoids, in fruits and vegetables, and Raman spectroscopy is a powerful candidate. Herein, we clarified the effects of Raman exposure time on quantitative and discriminant analysis accuracies. Raman spectra of intact tomatoes with various carotenoid concentrations were acquired and used to develop partial least squares regression (PLSR) and partial least squares discriminant analysis (PLS-DA) models. The accuracy of the PLSR model was superior (R² = 0.87) when Raman spectra were acquired 10 s, but decreased with decreasing exposure time (R² = 0.69; 0.7 s). The accuracy of the PLS-DA model was unaffected by exposure time (hit rate: 90%). We conclude that Raman spectroscopy combined with PLS-DA is useful for the on-site analysis of carotenoids in fruits and vegetables.

Keywords: Exposure time; PLS-DA; PLSR; Raman spectroscopy; Rapid analysis; Tomato.

MeSH terms

Carotenoids / analysis
Carotenoids / chemistry*
Discriminant Analysis
Least-Squares Analysis
Solanum lycopersicum / chemistry*
Spectrum Analysis, Raman / methods
Time Factors

Substances

Carotenoids