This work set out to examine the methodologies of dry hopping, compare different hop materials, and look at the extraction behavior of different types of hop compounds. This work consists of two discrete studies, where the first study informed the design of the second. The first study measured the concentrations of hop aroma compounds extracted from Cascade hops during dry hopping using a model beer system devoid of malt, yeast aromas, and hops. Cascade hops pelletized by four different processors yielded different particle size distributions and pellet densities. These pellets were dosed into a degassed medium (water, 6% v/v ethanol, pH 4.2) and the hop aroma extraction was measured periodically over a one week period. Solid phase micro-extraction (SPME) followed by gas chromatography (GC-FID) was used to analyze the levels of aroma compounds in the extraction medium. Variation in the hop pellet physical properties did not significantly impact the extraction rate of hop volatiles such as linalool, geraniol, limonene and myrcene with one exception. One treatment showed an increased absolute concentration of geraniol. Separately, dry hop aroma extraction was measured over a short time (1 day) at room temperature in an unhopped beer using small-scale (1L), stirred vessels. Irrespective of the hop form (whole or pellet), the concentrations of hydrocarbon terpenes peaked between 3 and 6 hours and subsequently declined, while the concentrations of terpene alcohols continued to increase throughout the 24 hour dry hop extraction. The rate of hop aroma extraction did not appear to be significantly influenced by hop pellet properties and occurred rather rapidly regardless of the hop form. The second study examined the extraction of hop aroma compounds during a pilot brewery scale (~4hL) dry hop treatment. Dry hop treatments consisted of whole cone hops and pellet hops (Cascade cultivar, 2011 harvest) which were dosed into cylindroconical vessels which were either stirred with a pump or left quiescent. Samples were taken for GC-FID and HPLC analysis as well as sensory evaluation at various time points between 30 minutes and 12 days. Polyphenol and alpha acid extraction was highest in a stirred system dosed with pellets. Hop aroma compound extraction was also the highest in the stirred system utilizing pellet hops. The sensory panel rated the stirred pellet samples as having the highest hop aroma, bitterness, and astringency. The results showed that hop flavor from dry hopping can be readily achieved with much shorter contact time than the current 4-12 day industry practice. / Graduation date: 2013

This study provides the model that first synthesizes strategic group theory with the New Empirical Industrial Organization (NEIO) approach in the international trade analysis, and uses the annual group data (1953-1988) from the U.S. brewing industry with two strategic groups (national producers and regional producers) in the presence of growing import competition. The main goal of study is to examine the impact of import and strategic group competition on strategic group behavior and market power in the U.S. brewing industry. Using the conjectural variation technique under the profit maximization assumption, the model estimates directly conjectural elasticities and the Lerner indexes incorporating firm behavior in competing with rivals from imports, and inside and outside each strategic group. The thesis shows the main following conclusions. Inside the group, national and regional brewers behave like Bertrand-type competitors and regional firms are more competitive than national firms. In the cross-group rivalry, national firms expect a cooperative response from regional brewers and regional firms expect an aggressive response from national producers. Holding possibly a sufficient niche market, import competition does not affect the behavior and market power of national and regional producers. As for over-all behavior, neither national nor regional firms behave like price-takers. National firms exert a significantly higher degree of market power than do regional firms, the market power of which appears to be harmed by national brewers. However, an average brewer exercises no market power in the industry as a whole. / Graduation date: 1997

With the purpose of expanding the understanding of the main causes that make creating and maintaining successful, strong brands a challenging issue for companies, a qualitative research is conducted in this thesis. It is based on an integrated model of Doyle’ and Stern’s along with Aaker’s approaches discussing building successful/strong brands with the following Doyle’ and Stern’s model discussing sustaining successful/strong brands; thereby selecting a single case study of Carlsberg Polska belonging to brewing potentates on the Polish beer market and two of its major brands – Carlsberg and Harnaś. The findings show that, in terms of building successful brands, introducing a quality product along with superior perceived quality, creating a basic brand along with brand awareness, augmenting a brand along with building brand loyalty as well as establishing a potential brand along with brand associations are the most crucial actions that had to be taken by Carlsberg Polska in order to win out a number 3 market-leader position. Concerning sustaining strong brands, on the other hand, the investigated firm needs to monitor competition and constantly revitalize and reposition its products in order to be the fastest growing beer producer on the Polish market.

Thesis (doctoral)--University of Helsinki, 2009. / Includes bibliographical references. Also available on the World Wide Web.

The quantity of alcohol produced through wort fermentation is fundamental to a malt’s quality. Good fermentability is dependent on many malt quality parameters but requirement for proteases to provide amino acids and peptides for yeast is poorly understood. The thesis investigated relationships between amino acid profiles, endoprotease activities and fermentability under different malting and brewing conditions. Methods for measuring individual wort amino acids, endoprotease activity and fermentability were modified or developed to better understand the relationships. Levels of lysine and glycine were affected the most by malting and the variability was not always well predicted by the standard FAN analysis. Cysteine endoprotease activity developed similarly to total amino acids levels but associations were not significant Amino acids were limiting to fermentability at low yeast pitching rates and with the use of high maltose syrups but malt modification was the key determinant of fermentability. Studies on non fermentable sugar content were recommended.

Glucoamylase, a saccharifying enzyme, is applied in the brewing industry to hydrolyse the dextrins of malted barley into simple sugars which can then be fermented by brewer's yeast. In order to establish the potential of glucoamylase from Lactobacillus amylovorus for application in the brewing industry, the main objectives of this study were: (1) to determine the cultural conditions for growth and glucoamylase production, (2) to purify the enzyme to homogeneity using chromatography and electrophoretic techniques, (3) to study biochemical properties of the purified enzyme, and (4) to clone the gene coding for glucoamylase, and characterize the recombinant glucoamylase. / The actively amylolytic Lactobacillus amylovorus ATCC 33621 produced an intracellular glucoamylase activity. Conditions for growth and glucoamylase production were maximized by using dextrose free MRS medium supplemented with 1% dextrin, at pH 5.5 and 37$ sp circ$C. Enzyme production was maximal during the late logarithmic phase of growth from 16-18 h. Crude cell extract showed optimal activity at pH 6.0 and 55$ sp circ$C. / Native and SDS-PAGE of the purified enzyme showed a monomeric protein of 47 kD. Glucoamylase activity was confirmed by activity staining using a starch/polyacrylamide gel where a zone of clearing was visible on a blue/black background stained with Kl/I$ sb2.$ Optimal pH, pl and temperature of purified glucoamylase were 4.5, 4.39 and 45$ sp circ$C, respectively. The enzyme was rapidly inactivated by temperatures above 55$ sp circ$C and was inhibited by heavy metals, e.g. Pb$ sp{2+}$ and Cu$ sp{2+}$ at 1.0 mM. EDTA did not inhibit the enzyme activity at a final concentration of 10 mM. Enzyme inhibition by 1 mM of p-chloromercuribenzoic acid (pCMB) and iodoacetate suggested that a sulfhydryl group was present in the enzyme active site. Kinetic studies of glucoamylase confirmed that the enzyme reacted preferentially with polysaccharides. HPLC analyses of the end products of enzyme action showed that glucose was the major end product of enzyme action and this glucose was responsible for end product inhibition. / The gene coding for glucoamylase was cloned into Escherichia coli using the STA2 glucoamylase gene of Saccharomyces diastaticus as a probe. Three glucoamylase producing transformants were identified as the insert sizes of about 5.2 Kb, 6.4 Kb and 5.9 Kb, respectively. When the characteristics of both recombinant and purified wild type glucoamylases were compared, both enzymes showed a similar pH range of 3.0-8.0, and temperature optimum of 45$ sp circ$C. The recombinant enzyme pH profiles were broader than that of the wild type and an optimum pH of 6.0 was obtained. This study has shown that glucoamylase from Lb. amylovorus is less heat stable than other bacterial glucoamylases and thus may be suitable for application in the brewing industry. Successful cloning of this gene coding for glucoamylase in brewer's yeast, Saccharomyces cerevisiae, would reap the advantageous properties of the enzyme while eliminating the costs of adding commercial enzymes.

The quantity of alcohol produced through wort fermentation is fundamental to a malt’s quality. Good fermentability is dependent on many malt quality parameters but requirement for proteases to provide amino acids and peptides for yeast is poorly understood. The thesis investigated relationships between amino acid profiles, endoprotease activities and fermentability under different malting and brewing conditions. Methods for measuring individual wort amino acids, endoprotease activity and fermentability were modified or developed to better understand the relationships. Levels of lysine and glycine were affected the most by malting and the variability was not always well predicted by the standard FAN analysis. Cysteine endoprotease activity developed similarly to total amino acids levels but associations were not significant Amino acids were limiting to fermentability at low yeast pitching rates and with the use of high maltose syrups but malt modification was the key determinant of fermentability. Studies on non fermentable sugar content were recommended.

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Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 95-101). Also available on the World Wide Web.