The compounds in the malt dissolved in the mash liquor during a standardized mashing process using finely ground malt (fine grist) are determined in this analysis.
Malt intended for use in beer brewing or elsewhere in the food industry
The Congress mash method primarily serves to determine the extract content of malt.
The extract content is determined by the weight ratio sL 20/20 of the wort on the basis of the official sugar tables (Plato tables) at 20 °C. sL 20/20 stands for the weight ratio of a volume of wort at 20 °C to the same volume of water at the same temperature.
Furthermore, the following is tested over the course of this analysis: Iodine test (saccharification time), odor of the mash, wort run-off, clarity of the filtered wort; the Congress wort is also used as a basis for a wide variety of further analyses.
Determination of xanthohumol and isoxanthohumol
All beers, beer-based beverages, wort, ethanol extracts, CO2 spent hops and xanthohumol products
Xanthohumol and isoxanthohumol are dissolved with acetonitrile from the sample and following separation, are determined using a Nucleodur C18 column and UV detection.
The cations in beer and wort are determined with this analysis.
This method is suitable for both wort and beer.
Inductively coupled plasma optical emission spectroscopy (ICP-OES) is a fast and reliable method for the laboratory analysis of metals. Inductively coupled plasma (ICP), a high frequency field of ionized gas, serves as a medium for atomizing and exciting the substances found in samples. Liquid, dissolved or aerosol samples are injected into the ionized gas stream. In emission spectroscopy, ICP can be used in conjunction with a number of optical and electronic systems either simultaneously or sequentially in multi-element spectrometers. In the plasma, the atoms and ions are excited to a higher energy state bringing about the emission of electromagnetic radiation (light), primarily in the ultraviolet and visible region of the spectrum. Metals ordinarily occur as ions in the temperature range typical for ICP of 6000 to 10000 K; however, non-metals and metalloids are only partially ionized.
ICP-OES operates within a very wide range. This usually encompasses six orders of magnitude in concentrations smaller than μg/l up to g/l, depending upon the element and the concentrations used for the set of analysis data. With ICP-OES, beer and wort can also be analyzed without prior processing of the samples, in contrast to AAS. Methods for determining the following in beer and wort will be described below: Al, B, Ba, Ca, Co, Cu, Fe, K, Mg, Mn, Mo, Na, P, Si, Sr, Sn and Zn.
This method is suitable for the determination of steam-volatile aroma compounds in wort.
Volatile aroma compounds are driven out of the sample through steam distillation. The ethanol distillate is adjusted to be alkaline and saturated with NaCl. The extraction of the aroma compounds is performed by shaking out with dichloromethane and the phases separated by centrifuging. The organic phase is further concentrated in a stream of nitrogen gas. An ammonia solution is added to remove the acids, because the acids would co-elute, thus preventing quantification of the target substances.
Determination of the concentration of the anions bromide, chloride, fluoride, nitrate, nitrite, oxalate, phosphate and sulfate through ion chromatography
Water, wort, beer, NAB and beverages as well as malt and hops
Separation of bromide, chloride, fluoride, nitrate, nitrite, oxalate, phosphate and sulfate through ion chromatography followed by conductivity detection
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.