Monitoramento das dicetonas vicinais durante o processamento da cerveja

Abstract

Among the main challenges that come at the industrial market of beer production in the current days, we can mention the provisioning of the market with the smallest possible cost and with quality, seeking to guarantee the customers' expectations and consumers. The stage of fermentation of the beer represents 70% of the whole necessary time approximately for his/her production, tends a compulsory nature of rigorous process controls. That stage is responsible for the formation of a series of by-products, as the local dicetonas (VDK). VDK possesses a low perception threshold for the consumer and they pass flavor and unpleasant odor. The objective of this work was to accomplish the attendance of VDK for gauging of the quality of the beer from I begin him/it of the fermentation to the filtration of the beer type pilsen, in three lots. They were monitored besides VDK some varied: as pH, extract and alcohol, temperature and cells in suspension. The applied methodology for the determination of VDK consists of extracting of the beer in fermentation, in maturation and filtered VDK through the distillation, with a reaction among distilled him/it and the reagent orto-fenilenodiamina, supplies a composition whose measured absorbance is in 335 nm. The pH was determined after the complete immersion of the electrode in the sample, the extract and alcohol of the fermentation / maturation samples and filtered were certain for the equipment Beer Analyzer. The temperature was obtained through the temperature monitor, and the cells in suspension were certain for counting of the number of cells, accomplished in camera of Neubauer in beer samples in fermentation / maturation. it was Obtained, as results of the total time of medium fermentation for the three lots of 144 hours, in that the medium levels of VDK were of 0,11mg/L. The average of the pH values same to 4, alcoholic content 4,70 v/v%, extract 2,00°P, concentration of cells in suspension close of 5x106cel/ml and temperature of 13°C. In the maturation he/she had duration averages inside for the three lots of 90 hours, and levels of VDK of the expected strip (0,07mg/L), the other variables stayed constant. In the filtration stage the levels of found VDK (0,07mg/L) average for the three lots, demonstrates that the beer type pilsen produced by the industry brewer is of quality, in which that values that VDK is inside of the allowed strip.