The method is suitable for the determination of water vapor volatile aroma compounds in beer.
Volatile aroma compounds are driven out of the sample through steam distillation. The ethanolic distillate is saturated with NaCl. Potassium hydrogen sulfite is added to separate carbonyl groups that might interfere with the analysis. The extraction of the aroma compounds is performed by shaking out with dichloromethane and the phases separated by centrifuging.
The method describes how to determine the boron content of water photometrically with a cuvette test.
Water intended for use as an ingredient in the production of beer (brewing liquor) or other foods
Borate ions react with azomethine-H, forming a yellow substance which can be measured photometrically. This method is suitable for analyzing samples collected from surface water and wastewater. Comparison with a sample-specific blank compensates for any minor coloration in water samples that may influence the analysis. Turbidity, which may interfere with the photometric determination, can be eliminated by pouring the water sample through a membrane filter.