Quantitative evaluation of anaerobic microorganisms in filtered beer, recovered beer, beer in keg, etc. Descriptors: general anaerobic count on beer, growth of microorganisms.

It is necessary to use EBC Microbiology 2.3.2.1 and 2.3.2.2 and 2.3.4.3 or 2.3.4.4

Quantitative detection of bacteria belonging to the genera Lactobacillus and Pediococcus. Descriptors. lactic acid bacteria, selective culture medium, microscopy, gram differentiation, catalase test, membrane filtration, incubation.

It is necessary to use EBC Microbiology 2.3.2.1, 2.3.2.2, 2.3.4.3, 2.3.5.4, 2.3.6.1 or 2.3.6.2 and 2.3.7 

Quantitative detection of strictly anaerobic Pectinatus and Megasphaera in bottled beer. Pectinatus and Megasphaera may arise as secondary contaminants when tunnel pasteurisation of the packaged product is not applied. Descriptors: anaerobic incubation, microscopy, selective medium.

It is necessary to use EBC Microbiology 2.3.7 and 2.3.6.1 and 2.3.6.2

Qualitative detection of strictly anaerobic Pectinatus and Megasphaera in bottled  beer. Pectinatus and Megasphaera may arise as secondary contaminants when tunnel pasteurisation of the packaged product is not applied. Descriptors: selective enrichment, anaerobic incubation.

It is necessary to use EBC Microbiology 2.3.5.1, 2.3.5.2, 2.3.5.3 and 2.3.5.4 and 2.3.6.1 and 2.3.6.2

Detection of culturable water bacteria. Descriptors: growth medium. For full details see: EN ISO 6222:2000 Enumeration of culturable micro-organisms — colony count by inoculation in a nutrient agar culture medium. 

It is necessary to use EBC Microbiology 2.3.3.1 and 2.3.4.2

Detection and enumeration of Escherichia coli and coliform bacteria in potable water for human consumption. Because of the low selectivity, the method is unsuitable for water that has not been disinfected. Descriptors: membrane filtration, selective medium. For full details see: EN ISO 9308-1: 2000 Water quality — detection and enumeration of Escherichia coli and coliform bacteria. Part 1: Membrane filtration method. 

Qualitative detection of microorganisms present and able to grow in wort. Descriptors: wort forcing test, detection of contaminants in wort, haze and CO2 development.

Classification of yeast isolates based on their ability to flocculate or form flocs and to de-flocculate. Descriptors: Hough Method, yeast analysis, determine the flocculation characteristic,  appearance of yeast suspensions.

It is necessary to use EBC Microbology 3.5.3.1

Classification of a suspension of yeast based on its rate of flocculation. Descriptors: Helm Method, sedimentation of yeast, calcium sulphate solution, yeast analysis.

The rapid estimation of yeast fraction in a slurry. Descriptors: Centrifugation of yeast mass, alkaline treatment.

Determination of the concentration of yeast in suspension by means of its dry weight. Descriptors: Dry Weight of Yeast, centrifugation, alkaline solution.

Rapid estimation of the percentage of “viable” yeast cells by counting dead cells. The method is applicable to all samples containing yeast. Descriptors: Methylene Blue / Violet Stain, ratio between total and dead cells.

Rapid estimation of the percentage of “viable” yeast cells by counting dead cells. Descriptors: Fluorescence Stain for yeast analysis,  fluoresce under UV-light, percentage of fluorescing cells.

Estimation of the percentage of viable cells capable of reproducing in a yeast sample. Descriptors: Slide culture techniques for yeast analysis, micro-colonies.

Primary differentiation of yeasts based on cell morphology. Descriptors: cell morphology of yeasts,  size, shape, vegetative reproduction of the cells, examine only pure cultures.

Quantitative estimate of the proportions of the different brewing yeast strains present in a mixed culture. Descriptors: cell colony morphologie,  yeast giant colonies, long-time incubation.

The method is intended for breweries that use different yeast strains in fermentation. lt may give a quantitative estimate of the proportions of the different strains present in a mixed culture depending on the strains. Descriptors: yeast morphology on WLN agar.

The laboratory storage of brewing yeast stocks cultures over a number of years. It has been demonstrated that the genetic stability and survival of brewing yeast strains are optimal after cryopreservation at ultra-low temperatures (below -139 °C) compared to other preservation methods. The cultures may be stored in plastic tubes or straws. The present method describes the preservation in polypropylene straws under liquid nitrogen or in mechanical freezers. Descriptors: yeast storage at ultra-low temperatures, cryoprotectant agent, long-term storage, cryopreservation,  dehydration, osmotic imbalance, intracellular ice.

This method describes the storage of brewing yeast strains for short periods of time (up to 6 months) in the laboratory. Changes in brewing yeast genotype following maintenance of the strains by repeated subculturing have been reported to influence yeast brewing performance. Preservation of the original properties of the stored yeasts in the long term is only recommended at ultra-low temperatures. For short-term storage (up to 6 months), other methods are available that allow safe and simple management of strains in the lab. Repeated subculturing for preservation of brewing yeast should be totally avoided. Descriptors: yeast subculturing for short-term storage.

It is necessary to use EBC Microbology 3.4.1

The shipment of brewing yeast strains from a supplier laboratory to a receiving laboratory  where they are to be propagated for industrial purposes. Descriptors: yeast strain transport, short-term storage, free from contaminant microorganisms.

It is necessary to use EBC Microbiology 3.4.2