Detection of harmful yeasts and bacteria in weakly acidic non-alcoholic beverages.
All non-alcoholic drinks with a pH value > 4.3.
Non-alcoholic beverages with a pH value greater than 4.3, e.g. vegetable juices, mixed drinks etc., are considered to be more susceptible to contamination. In addition to the fermentable yeasts, respiratory yeasts, moulds, lactic and acetic acid bacteria, it is also advisable to record the mesophilic and thermophilic bacterial counts (aerobic and anaerobic). These also provide initial indications of possible heat-resistant spore formers such as bacilli and clostridia.
Cloudy Hefeweizen beer samples from the fermentation tank to the filled bottle.
Preliminary microscopic analysis for obligate beer-spoilage organisms and wild yeasts with subsequent enrichment.
Unfiltered, cloudy beer samples
Analysis of the microbiological status of green beer samples, in particular the presence of obligate beer-spoilage organisms and wild yeasts.
Cloudy beer samples with sediment
Microscopic examination of the sediment for obligate beer-spoilage organisms and wild yeasts by selective enrichment.
Cloudy lager samples
To analyse the microbiological status of lager beer samples, especially to detect obligate beer-spoilage organisms and wild yeasts.
Cloudy beers
The shelf-life test involves direct incubation of the untreated, sealed sample with accompanying visual inspection of the biological states of a beverage (slime formation, creamy skin, agglomerates) and a final microscopic analysis.