AOAC RI ERP E-Book - DS DF

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

outliers, laboratories 3 and 13 had one statistical outlier and laboratory 12 had two statistical outliers, for a total of four statistical outlier pairs overall. The raw data and statistically paired data from the blind duplicate results for TDF reported by the collaborating laboratories are shown in Tables III and IV, respectively. Outliers and the reason for outlier removal, are indicated and footnoted in Table III. AOAC Official Method 2017. XX Total Dietary Fiber in Foods Rapid Integrated Enzymatic-Gravimetric-High Pressure Liquid Chromatography Method

(Applicable to plant material, foods, and food ingredients).

A. Principle A method is described for the measurement of total dietary fiber as defined by Codex Alimentarius Commission (CAC). The method quantitates higher molecular weight dietary fiber (HMWDF), which includes insoluble dietary fiber (IDF) and fiber which precipitates in the presence of 78% ethanol (SDFP); and fiber which is soluble in 78% ethanol (SDFS) (Figure 2017.xxA). Resistant starch (RS) is captured in the IDF fraction. This method combines the key attributes of AOAC Official Methods of Analysis 985.29 (11), 2001.03 (9), and 2002.02 (12) and is an update of AOAC Method 2009.01 (2, 3, 4). Duplicate test portions are incubated with pancreatic α - amylase (PAA) and amyloglucosidase (AMG) for 4 hr at 37 o C in sealed 250 mL bottles in a shaking water bath while mixing in orbital motion, or stirring with a magnetic stirrer, during which time non-resistant starch is solubilized and hydrolyzed to glucose and maltose by the combined action of the two enzymes. The reaction is terminated by pH adjustment followed by temporary heating. Protein in the sample is digested with protease. For the measurement of total dietary fiber, ethanol (EtOH) or industrial methylated spirits (IMS) are added and the IDF and SFDP are captured on a sintered glass crucible, washed with EtOH and acetone, dried and weighed. One of the duplicate residues is analyzed for protein, the other for ash. SDFS in the filtrate is concentrated, desalted with resins and quantitated by HPLC. This method differs from AOAC Method 2009.01 in that incubation time with PAA and AMG is reduced from AOAC Research Institute ERP Use Only

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