Analysis of an optimized pasteurization treatment and the microbial stability in craft beer: enhancing shelf life of the product.

Identifier:  TFM:329

Handle: https://hdl.handle.net/20.500.11797/TFM329

Authors:  de Lima e Silva, Ana Carolina

Abstract:
Pasteurization can be defined as a heat/thermal applied to beer, enabling the extension of the shelf life and at the same time, ensuring its microbiological stability. This treatment is not often the chosen one for the craft beer sector due to the belief that is can change the final tasting of the final product. This project aimed at identifying which is the best time and temperature ratio for the pasteurisation process, that could guarantee the microbiolgical stability of the beer without adding or changing significantly the principal caracteristics of the product. In order to do so, two different types of beer were chosen: Pilsen and WIPA. Different temperatures and pasteurization times - – 70°C to 2 minutes; 80°C to 1 minute; 90°C to 0,5 minutes -, were applied to them, following a microbiological and sensorial analisys in order to assure that their specific characteristics – colour, pH and bitterness. The relation between time-temperature at 80°C for 1 minute was the most suitable to the process, since the microbiological stability was sustained during the process and no differences on the sensorial analysis were found between control and the pasteurized sample. Keyword: beer, pasteurization, microbiological stability, shelf life, tasting/flavor