Mineral, spring and table waters as well as drinking waters that are to be marketed.
Qualitative detection of faecal streptococci in mineral water, spring water, table water and other drinking water bottled for distribution to the consumer by means of enrichment culture in double-concentrated azide-glucose broth [1].
Two-stage enrichment for the detection of harmful yeasts and bacteria in cloudy, non-alcoholic beverages using liquid pre-enrichment and pouring plate
All cloudy, non-filterable, non-alcoholic drinks with a pH value < 4.3.
Detection of harmful yeasts and bacteria using liquid enrichment and pouring plate.
Detection of Alicyclobacillus spp. in the NAB area by means of liquid pre-enrichment and streak.
All clear, non-alcoholic drinks and raw material samples.
Qualitative detection of Alicyclobacillus spp. by means of liquid enrichment and streak plate.
Detection of harmful osmophilic and osmotolerant yeasts, moulds and bacteria in NAB raw material samples
Raw material samples (e.g. fruit juice concentrates, sugar syrup, etc.) in the NAB area
The microorganisms should be quickly transferred from the lag phase to the log phase by the liquid pre-enrichment and then visualised as a colony in the agar plate.
Mineral, spring and table waters as well as drinking waters that are to be marketed.
Membrane filtration (MF) and immersion of the filter in single-strength azide-dextrose broth (corresponds to the methods in Annex 2, point 2b of Section 4 (3) of the German Mineral and Table Water Ordinance [1] and ASU Section 64 LFGB L59.00-2) [2].
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.