AOAC SPIFAN Nutrients ERP Review (March 14, 2019)

2016.13 (Jan. 2019) Carot-02 MLT Report FOR ERP USE ONLY DO NOT DISTRIBUTE

(c) Volumetrically pipet 5.0 mL of the appropriate ISTD solution from E(i) to each tube. (d) Add 1.5 mL KOH solution, C(l) , to each tube with a repeater pipet. (e) Shake on reciprocating shaker 5 min. (f) Add 8 mL extraction solution, C(p) , to each tube with a repeater pipet. (g) Shake 10 min. (h) With a repeater pipet or dispenser, add 10 mL water and 10 mL hexane to each tube. (i) Shake 1 min. (j) Centrifuge at 1000 rpm (or equivalent to 200 × g ) for 5 min. (k) Transfer a portion of the supernatant to a 12 mL scintillation vial. An adjustable pipette may be used. (1) Samples with individual carotenoid concentrations ≤50 μg/100 g – use 10 mL supernatant (2) Samples with individual carotenoid concentrations >50 μg/100 g – use 3 mL supernatant (l) Dry under nitrogen at ≤40 °C. (m) Reconstitute dried extract in sample solvent and vortex to dissolve, shaking if necessary to include any residue on the sides of the vial. (1) Samples with individual carotenoid concentrations ≤100 μg/100 g – add 0.5 mL. (2) Samples with individual carotenoid concentrations 100-500 μg/100 g – add 1 mL. (3) Samples with individual carotenoid concentrations 500-1000 μg/100 g – add 2 mL. (4) Samples with individual carotenoid concentrations 1000-1500 μg/100 g – add 3 mL. (n) Filter through 0.2 μm PTFE syringe filter prior to injection. G. Chromatography

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