This method describes the general requirements for boiler feed water:
Boiler feed water for use in the production of beer and other foods
The requirements for boiler feed water are detailed in the analysis methods listed below.
Determination of the quantity of solids in wort
unboiled lauter wort in the kettle, cast-out wort, wort at the midpoint of cooling (upstream from plate chiller)
The solids are separated at approx. 85 °C by means of filtration and are determined through weighing.
Determination of solids in wort
unboiled lauter wort in the kettle, cast-out wort, wort at the midpoint of chilling (upstream from the plate chiller)
Solids contained in the wort are separated by filtration at a temperature of approx. 85 °C and measured by weighing.
Determination of the amount of cold break material in the pitching wort
Cast-out wort, wort from the midpoint of chilling/pitching wort (without yeast)
The hot break material (trub) and any hop particles which may be present in the wort, must first be removed. After the wort has been cooled to 2 °C, it is filtered through a glass fiber filter. The residue remaining on the filter is dried and then weighed.
Cold break material or cold trub refers to all material that settles out in the process of chilling wort after separation of the hot trub or hot break material. Cold trub can be filtered out of the wort and primarily consists of proteins (48–57 %), tannins (11–26 %) and carbohydrates (20–36 %). The amount of cold break material in wort depends on the quality and composition of the raw materials, brewhouse equipment and wort handling. In academic and professional circles, opinions regarding the significance of cold break material for downstream processes and for the quality of the finished beer are strongly divided [1, 2, 5]. Under certain circumstances, the quantity of cold break material in wort may exceed 250 mg/l, especially where accelerated fermentation is practiced. Ultimately, this can detract from the flavor of the finished beer [3]. Breweries, where removal of the cold break material has been practiced successfully, determine the quantity of cold break in their pitching wort at regular intervals, in order to evaluate the efficacy of their separation equipment.