title: Comparison of spectrophotometric and HPLC methods for determination of carotenoids in foods.
abstract: This report is aimed at intra-laboratory and inter-laboratory comparison of the results obtained during spectrophotometric and HPLC analyses of lycopene, β-carotene and total carotenoids in tomato products and yellow maize flours/grits. Extensive statistical analyses are performed in order to identify the main sources of uncertainties which may occur when using: (i) different techniques/methods/approaches in the same/different laboratories, in various food samples, and (ii) to indicate the facts/conditions under which the biases between results may remain unidentified after applying statistical testing. Our data points to the inertness of t-test to detect significance of differences, particularly at low R values: in general, the higher correlation coefficient, the higher is sensitivity of statistical testing, especially of the paired t-test. Therefore, simple deviation of relationship line slope from unity could be used as additional evaluation parameter. This adds to reliable and objective quality assurance of foods in regard to carotenoids.
authors.affiliation: Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, HR-10000 Zagreb, Croatia. sluter@pharma.hr
authors.forename: Svjetlana
authors.initials: S
authors.lastname: Luterotti
authors.forename: Ksenija
authors.initials: K
authors.lastname: Marković
authors.forename: Mladen
authors.initials: M
authors.lastname: Franko
authors.forename: Dane
authors.initials: D
authors.lastname: Bicanic
authors.forename: Azamela
authors.initials: A
authors.lastname: Madžgalj
authors.forename: Kristina
authors.initials: K
authors.lastname: Kljak
mesh_terms: D002338:Carotenoids / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005433:Flour / Q000032:analysis*; D018551:Solanum lycopersicum / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D002338:Carotenoids