AOAC SPIFAN Nutrients ERP Review (March 14, 2019)

Carot-02 (February 2016) FOR ERP USE ONLY DO NOT DISTRIBUTE

(d) Calculate the response factor (RF) for each carotenoid based on average peak areas in the mixed carotenoid WS:

RF L

= (C L

/C A

) x (A A

/A L

)

Where C L

= the concentration of all-trans-lutein in the mixed carotenoid WS (μg/100 mL) C A = the concentration of apocarotenal in the mixed carotenoid WS (μg/100 mL) A A = the peak area of apocarotenal in the mixed carotenoid WS (AU) A L = the peak area of all-trans lutein in the mixed carotenoid WS (AU)

(e) Calculate the mass of apocarotenal (M A

), in μg, added to the test samples:

M A

= (C A

x V A

) x (4/50)

Where C A

= the concentration of apocarotenal in the apocarotenal WS (μg/100 mL) V A = the volume of ISTD solution added to each sample, in mL 4 = the volume of apocarotenal WS used in the ISTD solution, in mL 50 = the total volume of ISTD solution made, in mL

(f) Calculate the contents of all- trans lutein and cis isomers of lutein in the test samples:

L trans

= RF L

x (M A

/M S

) x (A L

/A A

) x 100

Where L trans

= the all- trans lutein in the sample (μg/100 g)

RF L = the response factor for all- trans -lutein M A = the mass of apocarotenal added to the test sample, in μg M S = the sample weight, in g A L = the peak area of all- trans -lutein in the sample chromatogram (AU) A A = the peak area of apocarotenal in the sample chromatogram (AU)

L cis

= RF L

x (M A

/M S

) x ([A 13cisL

+ A 13’cisL

+ A XcisL

]/A A

) x 100

Where L cis

= the cis isomers of lutein in the sample (μg/100 g) RF L = the response factor for all- trans -lutein M A = the mass of apocarotenal added to the test sample, in μg M S = the sample weight, in g A 13cisL = the peak area of 13- cis lutein in the sample chromatogram (AU) A 13’cisL = the peak area of 13’- cis lutein in the sample chromatogram (AU) A XcisL = the peak area of unidentified cis isomers of lutein in the sample chromatogram (AU) A A = the peak area of apocarotenal in the sample chromatogram (AU)