IMMUNOFLUORESCENT STAINING TECHNIQUE FOR THE DETECTION OF WILD YEASTS - PRACTICAL PROBLEMS

An apparent heavy wild yeast infection in pitching yeast has been detected using the immunofluorescent detection method. This infection could not be detected by conventional liquid forcing or plating techniques. The yeasts responsible were isolated and identified as Saccharomyces cerevisiae. The yeasts were very similar to the pitching yeast but varied in a number of respects associated with the cell wall such as flocculation character and giant colony morphology. The results suggest that the immunofluorescent‐positive (IP) yeasts are variants of the culture yeast. As a result of this work it is felt that although immunofluorescence is of value for the rapid detection of infection, it must always be used in association with more conventional microbiological techniques. 1979 The Institute of Brewing & Distilling