A New Method for Detection and Classification of Non-Volatile Nitroso Compounds in Beer Combining Gas Chromatography with Chemiluminescence Detection and Discriminant Analysis
Abstract
The problems of beer contamination with nitroso compounds have been addressed since 70's of twentieth century and have been partially solved, namely concerning the contamination by carcinogenic volatile N-nitrosamines. However, there is still a gap in the knowledge of non-volatile nitroso compounds in terms of both the determination of these compounds and description of their toxicity.
Therefore, a new method for their detailed study is necessary. Based on these facts, a new method permitting the detection and classification of non-volatile nitroso compounds groups in beer, such as N-nitroso, C-nitroso, and interfering substances.
Themethod is based on profiling of pyrolytic products of non-volatile nitroso compounds represented by GC chromatographic peaks determined by chemiluminescence detector and subsequent multivariate chemometric classification. The resulting classification function shows a good classification performance with total accuracy of 96.12% after method validation.
The method was applied and demonstrated on microbiologically contaminated beer sample.