ISI 44-1e Determination of Whiteness by Reflection

Return 1. Scope The method is applicable to starch   LT 12. Dec. 1966 2. Principle Light reflected from a sample relative to the reflection from magnesium oxide is measured.   3. Apparatus 3.1 Photometer (Whiteness meter / Reflection meter)  KETT C100 4. Reagents 4.1 Magnesium oxide standard 5. Procedure Fill starch sample in vial identical to the one used for (4.1) magnesium oxide. Follow instructions for the instrument used.

ISI 41-1e Determination of COD

Return 1. Scope The method is applicable to starch milk and hydrolysates   LT 12. Dec. 1966 Rev. LT 16. Dec. 1997 2. Principle Titration with NaOH to pH 8.3.   3. Apparatus 3.1 Burette 3.2 pH meter 3.3 Volumetric flask 50 ml   4. Reagents 4.1 Sodium hydroxide 0.1 N 4.2 Phenolphtalein: 1 g in 1 l ethanol 90%   5. Proce

ISI 40-1e Determination of Residual Juice in Potato Starch

Return 1. Scope The method is applicable to native potato starch   OJB 1960 Rev. LT 17.12.99 2. Principle Peroxidase in potato juice oxidises benzidin (as a hydrogen-donor) by means of hydrogen peroxyde as a hydrogen-acceptor. H 2 O 2  + AH 2  = 2H 2 O 2  + A. A is colored 3. Apparatus 3.1 Test tube 4. Reagents 4.1 Diluted hydrogen peroxide, 0.3%. 1 ml 30% H 2 O 2  is diluted to 100 ml with distilled water. 4.2 Benzidine solution, 0.5%. =.50 g benzidin (H 2 NC 6 H 4 -C 6 H 4 NH 2 ) is dissolved in 5 ml concentrated acetic acid

ISI 39-1e Determination of Conductivity of Starch

Return 1. Scope The method is applicable to native and modified starch.   LT 1989 Rev. LT 09 Sep. 1999 2. Principle Conductivity is measured in the water phase of a starch slurry   3. Apparatus 3.1 Conductivity meter with probe and temperature correction  Properly calibrated 3.2 Laboratory scale   4. Procedure Weigh sample on (3.2) to the nearest g in a  beaker Ambient   temperature Commercial starch: Add the equivalent quantity of distilled water and sti

ISI 38-3e Determination of Cold Water Solubles by Viscometer

Return 1. Scope The method is applicable to commercial starch.   Jan 1990 rev. Nov. 2002 2. Principle Viscosity of the water phase of a slurry is interpreted as concentration of cws   cws = cold water solubles 3. Apparatus 3.1 Brookfield viscometer RVT   4. Procedure Weigh a starch sample w g as is containing 50 g starch dry matter to the nearest g. Add distilled water at ambient temperature to a total of 200 g and stir for 30 minutes. Equivalent to 21 degree Beaumé starch slurry. The starch is allowed to set

ISI 37-1e Determination of Colour of Adjunct Syrup.

Return 1. Scope The method is applicable to liquid adjuncts.   LT 26/08/1999 2. Principle Spectrophotometric determination of colour.   3. Reagents 3.1 Kieselguhr   4. Apparatus 4.1 Spectrophotometer with 10 mm cells and adjustable to 430 nm +/-0.5 nm 4.2 Membrane filter holder and filters with pore size 0.45 micron   5. Procedure Dilute one part of sample with nine parts of distilled water. Dilution factor (f). Dilution factor (f) = 10.

ISI 34-1e Determination of Baumé of Starch Slurry by Aerometer

Return 1. Scope The method is applicable to starch slurry   LT 15 Jan 1998 2. Principle Slurry density is interpreted as concentration of slurry   3. Apparatus 3.1 Aerometer 0 - 10 Bé o 3.2 Aerometer 0 - 25 Bé o 3.3 Cylinder, slim 100 ml   4. Procedure Keep aerometers floating in cylinder or bucket with water. Fill cylinder (3.3) to the brim with starch slurry. Immerse appropriate aerometer (3.1 or 3.2) and let float. Read imm