Complex evaluation of technological changes—Impact on foam

Analytical Session
Adam Broz, Budejovicky Budvar, n.p., Ceske Budejovice, Czech Republic
Co-author(s): Petr Kosin and Jan Savel, Budejovicky Budvar, n.p., Ceske Budejovice, Czech Republic

ABSTRACT: Traditional brewers are facing the pressure of being fully competitive in the beer market. Their more difficult position comes from the use of traditional recipes and natural raw materials. The traditional brewing philosophy brings higher production costs due to higher energy demands and the higher price of raw materials. The traditional brewer has to be very careful about any technological changes. Possible savings in this case could be found by the increase of process effectiveness and minimization of extract loss in the production pathway. All steps to higher effectiveness must be proved in quality tests. Either analytical specifications or complex characteristics, and the sensory profile of a beer must be kept constant. One of the complex characteristics is beer foam, which is very sensitive to any technological changes and could indicate not only foam problems. A special method has been developed that allows measurement of foam potential in brewing intermediates. The method could be used as well for intermediates without any carbon dioxide content or sample filtration to obtain results immediately. Using this unique method, a study was implemented that tests the qualitative impact on beer when two extract loss decreasing techniques are used: wort recovery from sediment in a whirlpool and beer recovery from yeast after main fermentation, as well as after maturation. Different process modes of wort or beer recovery were tested to obtain a saving solution without any quality damage in the conditions of a traditional industrial brewery (volume 650 hL per brew, two-mash process, two-phase fermentation). A decanter separator installed after the whirlpool was tested in production scale. Separated wort was added into the wort line before cooling, followed by two-phase fermentation. Next to matrix foaming potential, amounts of wort recovered, removed solids, fatty acids, tannoids, nitrogen of MW > 5,000 in wort, wort concentration, dry matter, color, pH value, colloidal stability of beer, and beer sensory profile were analyzed. A cross-flow micro-filtration device was installed and run for recovery of beer from yeast. Recovered beer was added to young beer before maturation. Matrix foam potential, original extract, real extract, alcohol, color, pH value, bitterness, colloidal stability of beer, and beer sensory profile were analyzed. A new approach to judging the suitability of brewing intermediate recovery methods was used, with a focus on the complex evaluation of foaming potential. Using a very sensitive method of matrix foaming potential could reveal beer foam problems in early production phases. Results were compared with NIBEM and foam developed using a pouring test in final beer. Evaluation of such an important beer characteristic accompanied by stability and sensory measurements in final beer allows brewers to select optimal solutions for savings with no risk to quality.

Adam Broz received a Dipl.-Ing. (M.S. equivalent) degree in brewing and malting from the Institute of Chemical Technology Prague, Czech Republic, in 1999. He has been employed for Budweiser Budvar N.C. in Ceske Budejovice, Czech Republic, since his graduation. He worked as a technician (1999–2001), a brewhouse chief (2001–2004), a plant technologist (2004–2006), and a deputy brewmaster (2006–2008). Since 2009, he has been working as a technical and production director. He received a Ph.D. degree in biotechnology from the Institute of Chemical Technology Prague in January 2011.