A novel and enhanced approach for the assessment of the total carotenoid content of foods based on multipoint spectroscopic measurements

• Published in: Food chemistry Vol. 126; no. 4; pp. 1862 - 1869
• Main Authors: Meléndez-Martínez, A.J., Ayala, F., Echávarri, J.F., Negueruela, A.I., Escudero-Gilete, M.L., González-Miret, M.L., Vicario, I.M., Heredia, F.J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.06.2011; [Amsterdam]: Elsevier Science; Elsevier
• Subjects: Biological and medical sciences; Carotenoids; Characteristic vector; Citrus; Colour; equipment performance; food analysis; food composition; Food industries; Foods; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; General aspects; measurement; Methods of analysis, processing and quality control, regulation, standards; multipoint spectroscopic measurements; new methods; nutrient content; nutritive value; Orange juice; Quality control; reflectance; spectroscopy; Tristimulus colorimetry; Citrus; Carotenoids; Orange juice; Tristimulus colorimetry; Quality control; Characteristic vector; Foods; Colour; Measurement; Fruit; Rutaceae; Fruit product; Colorimetry; Fruit juice; Dicotyledones; Angiospermae; Pigments; Spermatophyta; Carotenoid; Vector; Food
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2010.11.167

► A novel approach considering several visible spectra wavelengths is described. ► It allows to asses the colour of orange juice with accuracy. ► Orange juice colour is related to the chemical composition (carotenoid content). ► It simplifies and improves the determination of the total carotenoid content. We have devised a more sensible approach to estimate the carotenoid content of orange juices, which can be regarded as a model system of food with intricate carotenoid pattern. For this purpose spectroscopic information at several wavelengths and spectra of the juices and not from their carotenoid extracts were considered, such that more accurate and rapid quantitative assessments can be achieved. The wavelengths proposed on the basis of the characteristic vector method were 420, 455, 515, 545 and 610nm or 420, 445, 510, 545 and 605nm, depending on the measurement conditions. The correlations between the carotenoid content and the reflectances at these wavelengths were very good (R=0.94 and 0.90, respectively). Additionally, it was demonstrated that the colour of the juices could be assessed with very good accuracy considering them. Due to its simplicity and rapidity, this method is intended to facilitate the quality control of the carotenoid content of foodstuffs in the industry and/or in the field.