AOAC RI ERP E-Book - DS DF
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 II and III, respectively. Outliers and the reason for outlier removal, are indicated and footnoted in Table II. AOAC Official Method 2017. xx XX Total Dietary Fiber in Foods Rapid Integrated Enzymatic-Gravimetric-High Pressure Liquid Chromatography Method Principle A method is described for the measurement of total dietary fiber as defined by Codex Alimentarius Commission (CAC). The method quantitates highhigher molecular weight dietary fiber (HMWDF), [ which includes insoluble dietary fiber (IDF) and fiber which precipitates in the presence of 78% aqueous ethanol (SDFP );)] and fiber which is soluble in 78% aqueous ethanol (SDFS ) (Figure 2017.xxA ). Resistant starch (RS) is captured in the IDF fraction ( Figure 2017.xxA ). . This method combines the key attributes of AOAC Official Methods of Analysis 991.43,985.29 (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 -amylase (PAA) and amyloglucosidase (AMG) for 4 hrh 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 solubilisedsolubilized and hydrolysedhydrolyzed to glucose and maltose by the combined action of the two enzymes. The reaction is terminated and AMG and PAA inactivated by pH adjustment andfollowed by temporary heating to ~ 100 o C . 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 scinteredsintered glass crucible, washed with ethanolEtOH and acetone, dried and weighed. One of the duplicate residues is analysedanalyzed for protein, the other for ash. SDFS in the filtrate is concentrated, desalteddeionised with resins and quantitatingquantitated by HPLC. This method AOAC Research Institute ERP Use Only (Applicable to plant material, foods, and food ingredients). A.
Method updated 2008--08-10 This copy printed 22 August 2017
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