ICUMSA Methods of Sugar Analysis presents the recommendations of the International Commission for Uniform Methods of Sugar Analysis (ICUMSA) that are based on thorough investigations of methods likely to prove practical and appropriate for the sugar industry. This book discusses the procedures for raw sugar polarization. Organized into two parts encompassing 21 chapters, this book begins with an overview of the various methods of determining sucrose by polarimetry, including the invertase method and the Jackson and Grill's method. This text then examines the methods of determining reducing sugars, which depends on knowing the amount of cuprous oxide precipitated from Fehling's solution. Other chapters consider the method to be applied for all beet products. This book discusses as well the principle of double sulfation that is necessary to ensure conversion of ash to sulfate. The final chapter deals with the evaluation of filter aids. This book is a valuable resource for chemists.
ICUMSA Methods Book.pdf
The ICUMSA Methods Book[3] contains detailed instructions for analyzing raw, cane, white, beet, molasses, plantation white and specialty sugars. Among these are methods for determination of dry solids content by polarimetry, densimetry and refractometry, color (extinction coefficient at 420 nm), reducing sugars, and the presence of metals such as arsenic and copper. The Methods Book also contains polynomials and tables (derived from the polynomials)[4] which relate the refractive index of solutions of pure sucrose, glucose, fructose and invert sugar to the strength of those solutions. These are to be used with the analysis methods that characterize sugars by refractometric means but find wide application outside the sugar industry as the sucrose polynomial is built into the firmware of modern refractometers and is the basis for calibration of purely optical refractometers which read in Brix. Temperature correction factors, also derived from the polynomials, are the basis for the Automatic Temperature Compensation features found in those instruments.[5] Thus, a vintner measuring the Brix of juice from his grapes by means of a refractometer accepts a sugar content reading based on the refractive properties of sucrose despite the fact that the primary sugar in grape juice is fructose, not sucrose. This usually does not result in significant error.
To determine if fuel, e.g., kerosene, gasoline, diesel, is contaminated or has degraded during storage time, a specific color measurement test, using the Saybolt color scale (ASTM D156, ASTM D6045), can be performed. Both ASTM methods are off-line methods. The Saybolt color scale range is from +30 (clear water / white) to -16 (dark yellow). ASTM D 1500 also describes the color testing of petroleum products.
For product and production control beer brewers have to measure color intensity and turbidity (haze) in EBC units, roughly darkness of a beer or wort, as well as quantifying turbidity (haze) of beer. The Standard Reference Method (SRM) and European Brewery Convention (EBC) methods have mainly replaced the "Degrees Lovibond" or "L" scale, with SRM results being approximately equal to L. The Standard Reference Method describes the use of a spectrophotometer or photometer measuring the attenuation of light at 430 nm wavelength, (blue).
With the ICUMSA methods book detailed instructions are given to analyse all types of sugars, molasses etc. For color evaluation the extinction at 420 nm wavelength is controlled at defined optical path length. Pure, white sugar absorbing less light (value 45) compared to brown sugar at value 1000 for high absorption. For the calculation of the ICUMSA value additional parameters must be tested, such as density, refraction index. 2ff7e9595c
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