ISI 09-2e Determination of Fibre in Starch by Weight
ISI 09-2e Determination of Fibre in Starch by Weight 1. Scope The method is applicable to native potato and cassava starch LT 1994 Rev. LT 11. Dec. 1997 2. Principle Starch is hydrolyzed and filtered. Fibre defined as non-soluble impurities are retained, dried and determined by weight. Cornstarches do not filter properly. 3. Apparatus 3.1 Analytical balance weighing to the nearest 1 mg. 3.2 Shaking boiling water bath. 3.3 Büchner funnel or Sartorius 250 ml glass vacuum filter funnel. Use a high flux filter. Do not use a glass frit filter support 4. Reagents 4.1 Dilute hydrochloric acid 0.1 N 5. Procedure 100.0 g (w 1 ) sample is slurried in a 1000 ml conical flask with 600 ml acid (4.1) Hydrolysis Place flask in boiling water bath (3.2) for 30 min Shake min. until starch is gelatinised Filtration Filter hot on filter (3.3). Flush flask and filter with 100 ml hot water. Increase hydrolysis parameters if flux too low Dry filter at 105 o C over night - min 12 hours. Weigh filter