Portable near‐infrared and Raman spectroscopic devices as complementary tools for instantaneous quality control of turmeric powder

• Published in: Phytochemical analysis Vol. 34; no. 5; pp. 518 - 527
• Main Authors: Cruz, Jordi, Khongkaew, Putthiporn, Bertotto, Judit Puig, Cárdenas, Vanessa, Alcalà, Manel, Nuchtavorn, Nantana, Rojsanga, Piyanuch, Suwanvecho, Chaweewan, Phechkrajang, Chutima
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.07.2023
• Subjects: Calibration; Curcuma - chemistry; curcuminoids; Diarylheptanoids; High performance liquid chromatography; Industry 4.0; Infrared analysis; Infrared spectroscopy; Least-Squares Analysis; Liquid chromatography; Mathematical models; Near infrared radiation; Plastics; Portable equipment; portable NIR; portable Raman; Powders; Quality assurance; Quality Control; Regression analysis; Spectra; Spectroscopy, Near-Infrared - methods; Technology assessment; turmeric powder; turmeric powder; curcuminoids; portable NIR; portable Raman
• ISSN: 0958-0344; 1099-1565
• DOI: 10.1002/pca.3231

Introduction Process analytical technology (PAT) guidance is implemented in the quality assurance of phytocompounds to achieve the Industry 4.0 concept. Near‐infrared (NIR) and Raman spectroscopies are feasible for rapid, reliable quantitative analysis through transparent packaging without removing the samples from their original containers. These instruments can serve PAT guidance. Objective This study aimed to develop online portable NIR and Raman spectroscopic methods for quantifying total curcuminoids in turmeric samples through a plastic bag. The method mimicked an in‐line measurement mode in PAT compared with placing samples into a glass vessel (at‐line mode). Materials and methods Sixty‐three curcuminoid standard‐spiked samples were prepared. Then, 15 samples were randomly selected as fixed validation samples, and 40 of the 48 remaining samples were chosen as calibration set. The results obtained from the partial least square regression (PLSR) models constructed by using the spectra acquired from NIR and Raman were compared with the reference values from high‐performance liquid chromatography (HPLC). Results The optimum PLSR model of at‐line Raman was achieved with three latent variables and a root mean square error of prediction (RMSEP) of 0.46. Meanwhile, the PLSR model of at‐line NIR with one latent variable offered an RMSEP of 0.43. For the in‐line mode, PLSR models created from Raman and NIR spectra had one latent variable with RMSEP of 0.49 and 0.42, respectively. The R2 values for prediction were 0.88–0.92. Conclusion The models established from the spectra from portable NIR and Raman spectroscopic devices with the appropriate spectral pretreatments allowed the determination of total curcuminoid contents through plastic bag. This study aimed to develop online portable NIR and Raman spectroscopic methods, the fesible instruments for Process Analytical Technology (PAT), for quantifying total curcuminoids in turmeric samples through a plastic bag, which is a situation of in‐line measurment mode in PAT, compared to placing samples into a glass vessel (at‐line measurement mode). In summary, PLSR models establised from the portable NIR and Raman devices with appropriate spectral pretreatments allowed the determination of the total curcuminoids contents through plastic bag.