Applicable for all (laboratory) worts
The Congress wort is heated in order to inactivate the amylolytic enzymes, and afterwards, yeast is added and the wort is allowed to completely ferment out at a minimum temperature of 20 °C in a fermentation tube (fig. 1). The difference in the extract before and after fermentation is measured in order to calculate the limit of attenuation.
Applicable for all (laboratory) worts
The Congress wort is heated in order to inactivate the amylolytic enzymes. Afterwards, 16 g/100 ml yeast is added, and the wort is allowed to completely ferment out in approx. 7 h.
Determination of the fermentable extract in beer and wort
This method is suitable for all types of beer and wort.
Beer or wort is fully attenuated under agitation in an Erlenmeyer flask after yeast has been added. From the difference between the extract content prior to fermentation commencing (original gravity) and after fermentation is complete, the limit of attenuation is calculated.
Real extract minus apparent extract of the fully attenuated beer (from which the alcohol was removed) yields the value for “apparent attenuation”, because during the final stages of attenuation alcohol is produced.
The portion, which has actually been fermented, can be calculated through multiplication by the factor 0.81. This factor is related to the so-called attenuation quotient q [1].
The method describes the procedure for conducting a paired comparison test.
beer, beer-based beverages, non-alcoholic beverages, mineral water
The method can be employed to reveal slight differences between two samples, e.g., the type and expression of specific attributes or the overall impression as well as for training and selection of individuals for a tasting panel.
Suitable for all beverages
The energy value or caloric value of beer is calculated according to Council Directive 90/496/EEC and is based upon the amount of protein, carbohydrate, alcohol, glycerin and organic acids. For performing the calculation, caloric values are attributed to 1 g of each of the following: 17 kJ (4 kcal) of protein or utilizable carbohydrate, 29 kJ (7 kcal) of ethanol, 13 kJ (3 kcal) of organic acid, and 10 kJ (2.4 kcal) of higher alcohols. (Fat is not included in the calculation for beer.)
This is a mathematical method for calculating the dextrin content as a difference between the total glucose content and the fermentable extract as determined through analytical methods.
Suitable for beer
The dextrin content is calculated through multiplication of the difference between the total glucose content and the fermentable extract by a factor of 0.915.