P-1
Brewing process and nitrogen compounds in beer
Presenter: Maria Daria Fumi, Institute of Oenology and Food Engineering, Università Cattolica del Sacro Cuore, Piacenza, Italy
Co-Authors: G. Donadini, A.I.D.A.S.A., Institute of Entomology and Plant Pathology, Università Cattolica del Sacro Cuore, Piacenza, Italy; and Roberta Galli, Institute of Oenology and Food Engineering, Università Cattolica del Sacro Cuore, Piacenza, Italy

Nitrogen compounds are important for the fermentation rate and are recognized as playing an important role in taste and stability of beer. This paper examines the nitrogen compounds in two different worts (Spugen Dry type and Gold type, respectively) and their evolution during the main steps of the brewing in a full-scale process. The quantitative and qualitative content of total nitrogen and nitrogenous fractions is found to be dependent on the raw materials and on the process technologies. In particular, we evidence a lower amount of nitrogen compounds in the Splugen Dry type of wort, i.e., a pure malt wort, than in the Gold type wort produced with maize as an adjunct; higher amino acid and ammonium consumption during fermentation in the wort with the lowest nitrogen level; differences in the utilization of the same amino acids in the fermented worts; and a decrease of the nitrogen compounds after mashing liquor filtration and fermentation as attended, respectively. Further investigations focusing on the effects of wort production parameters on the nitrogen compound content at pre- and postfermentation stages were being planned at the time of writing in order to improve the efficiency of the fermentation process and the overall quality of the finished beer.

Maria D. Fumi graduated in biology. She is a research scientist at the Faculty of Agriculture, U.C.S.C., Piacenza, Italy. She is a lecturer of food biotechnology, wine microbiology, and wine microbiological control at the Agriculture Faculty, with a degree in agriculture science and technologie and viticulture and oenology. She is a member of CEN (European Committee for Standardization) WGION working group. She is also involved in the EU project 2LK1-CT2001 on risk assessment and integrated OTA management in grape and wine. Her main research activities concern biotechnological application in fermented beverages (in particular wine, beer, and vinegar) to optimize the fermentation process, to reduce OTA contamination, and to improve chemical and sensorial characters. She's also involved in studies on indoor air quality in food-compatible environments.