AOAC OMB Final Action Recommendation (December 2019)-2016.14

2016.14 (October 2019) – FOS-03 METHOD

FOR ERP USE ONLY DO NOT DISTRIBUTE

Figure 2016.14D. Example of calibration curves obtained on a CarboPac PA20 column, but without post- 359 column addition, resulting in reduced quantitative range. A: Glucose B: Fructose.

360 361

362

363

364

365

366

Appendix A: Sucrase/β-amylase/pullulanase/maltase enzyme mixture check test 367

To check performance and suitability of sucrase enzyme mixture, equal aliquots (100 µL) of sucrose 368

solution (0.75 mg/mL) and fructooligosaccharide (FOS) ingredient solution (0.75 mg/mL) are mixed and 369

treated with the sucrase enzyme mixture (200 µL) to be tested. Water is added (100 µl) and the mixture 370

is incubated at 40 °C for 90 min (or the relevant conditions to be tested). After centrifugation (5 min at 371

10 000 x g ), an aliquot of the supernatant (100 µL) is transferred into a vial suitable for the autosampler 372

instrument, diluted with water (400 µL) and mixed. This solution is injected onto an HPAEC-PAD 373

instrument (conditions described below) and the chromatographic profile obtained is compared with the 374

one obtained from the same solution (sucrose/FOS) not treated with the enzyme mixture (200 µL of water 375

376

instead of the enzyme mixture).

Note: It is highly recommended to perform this test with a FOS ingredient of low DP (average 3-5) which 377

has been produced by partial hydrolysis of inulin, as these seem to be the most sensitive to sucrase side 378

379

activities or impurities.

20