Hochschule Neubrandenburg, 2009
Abstract: The aim of this diploma thesis is the evaluation of the applicability of a method to determine the microbiological safety of fruit juices in the company Eckes Granini Deutschland. The functionality of the regarded measurement instrument "Promilite III" provided by the manufacturer Promicol is based on bioluminescence. In the context of this work different tests were conducted. At first it the alteration of the ATP-concentration of the microbiological cells over a fixed period was observed. Furthermore a comparison between "Promilite III", the currently used technique of flow cytometry with the instrument "D-Count" and the conventional method for the detection of microorganisms with culture media was drawn. For this purpose different products were inoculated with several dilutions of Saccharomyces cereviseae, Candida parapsilosis, Lactobacillus rhamnosus and Aspergillus niger. Moreover the daily controls of the products were performed with "Promilite III". Consequently the resemblance of the results obtained from "Promilite III" and "D-Count" was assed. Concerning the low sample volume demanded by "Promilite III" the possibility to increase this by means of centrifugation was also examined. As a result the effects of this procedure on the measured values were observed.
diploma thesis free access