@phdthesis{digilib75478,
           month = {January},
           title = {UJI ADULTERASI SERBUK SECANG DENGAN PEWARNA SINTETIS KARMOISIN MENGGUNAKAN SPEKTROFOTOMETER UV-VIS DENGAN PENDEKATAN KEMOMETRIKA},
          school = {UIN SUNAN KALIJAGA YOGYAKARTA},
          author = {NIM.: 22106030023 Nur Intan Sheila Rahmah},
            year = {2026},
            note = {Karmanto, S.Si., M.Sc.},
        keywords = {Adulterasi, Serbuk Secang, Pewarna Sintetis, Karmoisin, Resolusi Kurva Multivariat, Regresi Kuadrat Terkecil Parsial (PLSR)},
             url = {https://digilib.uin-suka.ac.id/id/eprint/75478/},
        abstract = {Adulteration of the natural colorant secang (Caesalpinia sappan L.) with the synthetic dye carmoisine may compromise product quality and food safety, and poses an analytical challenge due to matrix complexity and spectral overlap. Therefore, an analytical approach capable of reliably distinguishing and quantifying the contribution of each component is required. This study aimed to analyze the UV?Vis spectra of secang powder solutions, carmoisine, and their mixtures; to resolve and identify the contributions of secang and carmoisine within the mixed system using Multivariate Curve Resolution (MCR); and to develop a quantitative model based on Partial Least Squares Regression (PLSR) for predicting component levels in potentially adulterated samples. Solutions of secang, carmoisine, and various mixtures were measured using a UV?Vis spectrophotometer, and the resulting spectral data were analyzed chemometrically using MCR and PLSR. Spectral analysis showed that secang exhibited characteristic absorption peaks at approximately 283, 441 and 538 nm, while carmoisine displayed a dominant absorption band near 514 nm. In the mixed samples, overlapping absorption bands accompanied by intensity variations were observed. MCR modeling successfully resolved the mixed spectra into individual component spectra, with the decomposed spectra of component 1 closely resembling secang and component 2 corresponding to carmoisine, showing similarity levels of 93?99\% based on cluster analysis. A PLSR model was then constructed to validate the quantitative analysis of secang and carmoisine, yielding an R? value of 0.9998761, a slope close to unity, and an RMSEC of 0.1414941. Predictions for test samples indicated carmoisine concentrations of 0.70 ppm, 8.83 ppm, and 17.27 ppm, alongside secang concentrations of 101.16 ppm, 64.80 ppm, and 5.59 ppm, respectively, all of which were highly consistent with the model space and suitable for quantitative interpretation. Overall, the results demonstrate that the combined application of UV?Vis spectroscopy, MCR, and PLSR is effective for detecting and quantifying carmoisine adulteration in secang-based natural colorants.}
}