AOAC RI ERP E-Book - DS DF

OMAMAN-38 B: Collaborative Study Protocol Expert Review Panel Use Only September, 2017

mixing with 1.5 g of Amberlite ® FPA53 (OH − ) and 1.5 g of Ambersep ® 200 (H + ) resins over 5 min and the supernatant was analysed by HPLC with no Bio-Rad ® de- ashing pre-cartridges in place; c) Sample b) was analysed with a Bio-Rad ® deionising pre-cartridges in place. Desalting with resins in a polypropylene tube, as described here, removes > 95% of the salt from the sample, thus ensuring more efficient use of the expensive Bio-Rad ® de-ashing pre-cartridges. This desalting step increases the effectiveness of the deionising cartridges and allows up to 10-times more samples to be chromatographed before the need to regenerate or replace the deionising cartridges Figure 2007.xxF. Desalting of samples for HPLC. Five (5) mL of concentrated eluate mixed with 1.5 g of Amberlite ® FPA53 (OH − ) and 1.5 g of Ambersep ® 200 (H + ) resins in a polypropylene tube. Figure 2007.xxG. Photograph of HPLC setup for measurement of SDFS, highlighting the two TSK-GelG2500PWXL HPLC columns, the TSK-Gel PWx1guard column and a Bio-Rad cartridge containing cation and anion deionizing cartridges.

Figures Figure 2007.xxA. Rapid integrated total dietary fiber assay procedure showing the key steps in the procedure.

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Figure 2007.xxB. Incubation of samples in Fisherbrand ® incubation bottles in a shaking water bath, showing custom made polypropylene bottle holder.

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