Search: monitoring brewhouse yield

Since determination of the hot wort yield can be problematic and the cold wort yield as described above does not represent a measure of the total extract obtained from the grain bill, an attempt has been made to record all of the extract recovered, with the exception of that remaining in the spent grain. This value is then compared to the laboratory yield. The result is expressed as the total yield (overall brewhouse yield) (OBY_CW) in %.

The brewhouse yield/hot wort yield represents the extract present in one batch of wort relative to the raw materials used to produce the wort. The malt, any supplements added to the mash, and brewhouse operations determine brewhouse yield.

An assessment of brewhouse operations and processes is possible through comparison with the laboratory yield, prepared using the same malt and supplements in the mash. However, the brewhouse yield does not allow a distinction to be made regarding where extract losses occur in the brewhouse, i.e., whether they stem from the mashing or lautering process and in which proportions. For this, a spent grain analysis is required.

Instead of brewhouse yield, quite often the cold wort yield is calculated. Cold wort yield is particularly recommended for wort produced using adjuncts. Extract yield is understood as the amount of extract in a batch of wort relative to the amount of extract in the raw materials used to produce the wort.

The fermentation cellar yield is calculated using the value determined for the amount of extract contained in a batch of wort relative to the amount of extract present in the raw materials used to produce the wort.

The moisture content of malt is determined through the loss in mass during a standardized drying process, in which ground malt is dried at a defined temperature within a specified time in an electrically heated drying oven. The moisture content is determined through the difference in the weight of the malt prior to and after drying.

It should be borne in mind that allowing the weighed sample of ground malt to stand for any length of time prior to performing the analysis can alter the outcome, depending upon the humidity in the air. For this reason, it is recommended that the analysis be carried out immediately after grinding the malt.

For rapid methods, refer to analysis methods R-110.40.022 Moisture Content in Barley – Infrared Drying to R-110.40.183 Moisture Content in Barley – NIT (Verweise).

Since the Congress mash method does not accurately quantify the extract content of malt, an attempt was made to eliminate the sources of error present in the method. The method described below incorporates the procedure for producing a Congress mash according to the EBC, followed by a complete extraction of the dissolved substances with a suitable apparatus. After the extraction is complete, the weight is determined. This method is preferred for determining brewhouse yield (e.g., during brewhouse equipment commissioning tests).