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O efeito país de origem no processo de avaliação de cervejas especiais e a intenção de compra dos consumidoresBassani, Michel Gehlen 31 March 2017 (has links)
O mercado globalizado trouxe ao cenário brasileiro produtos provenientes de diversos países, sejam esses montados, desenvolvidos ou fabricados em mais de um país. Diante disso, surge a necessidade de entender como o consumidor percebe esses produtos importados e qual o seu comportamento diante desses. Para entender o comportamento do consumidor foi investigado o efeito do país de origem na percepção do consumidor, e sua relação com a qualidade percebida, disposição de preço a pagar, intenção de compra, abertura cultural e etnocentrismo, em um cenário considerado emergente no Brasil, que é o da cerveja especial. Dando sequência ao estudo, o mesmo foi realizado por meio de um método experimental, com um design 4 (País de Orígem: China, Alemanha, Brasil e sem identificação) x 1 (Produto: cerveja especial pilsen), compondo, dessa forma, quatro grupos experimentais. A pesquisa foi realizada através de um questionário com escalas do tipo Likert de sete pontos, que foi disponibilizado junto a uma prova de cerveja especial e um cartão contendo informações da cerveja e do país de fabricação. Por seguinte, para análise dos dados, foi realizada uma abordagem estatística quantitativa onde o processamento dos dados ocorreu por meio de uma análise multivariada de variância, aplicando-se testes post-hoc. A amostra foi composta por 159 respondentes que foram distribuídos nos quatro grupos experimentais. Os resultados comprovam que o efeito país de origem atua de forma significante na qualidade percebida, disposição de preço a pagar e intenção de compra dos consumidores, e que o consumidor brasileiro apresenta uma baixa pré-disposição ao protecionismo do consumo de produtos nacionais, bem como está aberto a experienciar interações com culturas estrangeiras. / Globalized market has brought products from different countries to the Brazilian scene, whether assembled, developed or manufactured in more than one country. Given this, the need arises to understand how the consumer perceives these imported products and what their behavior is in front of them. In order to understand consumer behavior, we investigated the effect of country-of-origin on consumer perception and its relationship with perceived quality, price-willingness to pay, purchase intent, cultural openness and ethnocentrism, in a market considered to be emerging in Brazil, which is speciality beer. Study was conducted by means of an experimental method, with a design 4 (Country of Origin: China, Germany, Brazil and no-ID) x 1 (Product: speciality pilsen beer), thus composing four experimental groups. Research was carried out through a questionnaire with seven-point Likert kind scale, which was made available with a speciality beer tasting and a card containing beer and country information. For data analysis, a quantitative statistical approach was performed with data processed through multivariate analysis of variance, applying post-hoc tests. The sample consisted of 159 respondents who were distributed in the four experimental groups. Results show that the country-of-origin effect plays a significant role in the perceived quality, willingness to pay and consumers' purchase intentions as well as that Brazilian consumer presents low bias towards protectionism (when it comes to consumption of domestic products), being open to experiencing interactions with foreign cultures.
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Cerveja envelhecida em barril de madeira, aspectos químicos e microbiológicos / Aged beer in wooden barrels, chemical and microbiological aspectsLuís Henrique Poleto Angeloni 18 November 2015 (has links)
Nas últimas décadas, houve um aumento do consumo de cerveja no Brasil e no resto do mundo. Existem diversos conceitos e metodologias que diferenciam os estilos de cerveja, sejam nas modificações dos processos de produção, uso de diferentes ingredientes, fermentações em fermentadores de diferentes tipos, metodologias de envase, utilização de madeira na maturação da bebida, entre outros. Paralelamente à evolução dos conhecimentos científicos em Microbiologia, tais como, o crescente entendimento da fisiologia celular, as técnicas de imobilização da levedura cervejeira e o isolamento de novas estirpes que fornecem características aromáticas diferenciadas às cervejas. O armazenamento de bebidas em barris de madeira é amplamente utilizado desde a antiguidade na produção de bebidas, seja na forma de armazenamento e no aumento da complexidade do produto. O objetivo desta pesquisa foi avaliar a formação de alguns compostos aromáticos durante o envelhecimento de cerveja tipo Flanders Red Ale em barris de madeira, levando em consideração aspectos químicos e microbiológicos tais como: congêneres de maturação analisando os conteúdos de compostos fenólicos de baixo peso molecular determinados por cromatografia líquida de alto desempenho, congêneres voláteis (aldeídos, ésteres e álcoois superiores) determinadas por cromatografia em fase gasosa e as propriedades microbiológicas da cerveja como viabilidade celular, meios de cultivo diferenciados para isolamento de levedura totais, bactérias ácidos acéticas, bactérias láticas e meio modificado para isolamento de Brettanomyces. O estudo foi realizado nas dependências da microcervejaria do Departamento de Agroindústria, Alimentos e Nutrição da Escola Superior de Agricultura Luiz de Queiroz, Piracicaba (SP). A fermentação primária do mosto cervejeiro foi conduzida à 23°C em fermentador cilíndrico cônico de inox, após refrigeração a 0°C por duas semanas a cerveja foi armazenada em barris (50 litros) de carvalho americano à 25°C por três e cinco meses. Após a maturação, uma cerveja nova (Young Ale) foi produzida e misturada (Blend) com a cerveja envelhecida em diferentes proporções: cerveja Young Ale; blends com 33% e 66% de cerveja envelhecida; 100% cerveja envelhecida, após os Blends, as cervejas foram engarrafadas e armazenadas por um período de três meses para início das análises químicas, microbiológicas e sensoriais. Ocorreram alterações químicas e microbiológicas que favoreceram o aumento da complexidade da cerveja após passar por um período de armazenamento em barril de carvalho, sendo que, essa alteração foi maior proporcionalmente ao aumento do tempo de armazenamento da cerveja. / In recent decades, there has been an increase in beer consumption in Brazil and around the world. There are many methodologies and concepts that differentiate styles of beer, are the modifications of the production processes, use of various ingredients fermentations in fermenters of different types of packaging methodologies, wood use in beverage maturation, among others. Parallel to the development of scientific knowledge in microbiology, such as the growing understanding of cellular physiology, the immobilization techniques of brewing yeast and isolation of new strains that provide aromatic characteristics differentiated the beers. The storage of drinks in wooden barrels is widely used since antiquity in the production of drinks. The objective of this research was to evaluate the formation of some aromatic compounds at Ale type beer aging in wooden barrels, taking into account chemical and microbiological aspects such as: maturation of similar analyzing the content of phenolic compounds of low molecular weight determined by chromatography high performance liquid volatile counterparts (aldehydes, esters and higher alcohols) determined by gas chromatography using a flame ionization detector and microbiological properties of beer analyzing cell viability, different culture media for total yeast, bacteria acetic acid, Lactic acid bacteria and growth medium modified to Brettanomyces. The study was conducted in the microbrewery premises of the agribusiness department, food and nutrition Luiz de Queiroz College of Agriculture, Piracicaba (SP). The primary fermentation was conducted at 23° C in tapered cylindrical stainless steel fermenter after cooling to 0° beer was stored in barrels (50 liters) American oak at 25° C for three and five months. After maturation, a new beer (Young Ale) was produced and blended (blend) with the aged beer bottled and stored for analysis. After maturation, a new beer (Young Ale) was produced and mixed ( Blend ) with the beer aged in different proportions : Young beer Ale ; blends of 33 % and 66 % of aged beer; 100 % aged beer, the beers were bottled and stored for a period of three months to the beginning of the chemical, microbiological and sensory analysis. Microbial and chemical chenges accurred that favored increased complexity of the beer after passing through a storage period in oak barrel, and that changes was greater in proportion to the increase beer storage time.
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Economic Experiments in Honor of Thorstein Veblen / Expériences économiques en l'honneur de Thorstein VeblenGoldstein, Robin 03 June 2019 (has links)
Thorstein Veblen, auteur de La théorie du loisir (1899), est commémoré en sciences économiques par «l'effet Veblen», terme introduit par Harvey Leibenstein pour représenter une réponse positive de la demande des consommateurs à une augmentation de prix. L’article de Leibenstein de 1950 qui introduit «l’effet Veblen» ne cite pas Veblen parmi ses 17 références.Je commence cette thèse en revisitant la théorie de Veblen sur le comportement du consommateur et en évaluant son traitement ultérieur dans la littérature économique. Je trouve que Leibenstein (1950) interprète mal le concept de «consommation ostentatoire» de Veblen et contredit les prédictions empiriques de Veblen.Comment la théorie de Veblen pourrait-elle être interprétée plus fidèlement et avec plus de pertinence pour les marchés actuels? Dans cette thèse, j'essaie d'observer certains attributs et certaines primes de Veblen sur les marchés de consommation actuels.Je présente des résultats expérimentaux sur les marchés de la vente au détail américains de bière (partie II), de vin (partie III) et de produits alimentaires (partie IV). J'utilise diverses techniques expérimentales, notamment des enquêtes auprès des consommateurs, des expériences de dégustation à l'aveugle, des expériences de laboratoire et des expériences d'infiltration. / Thorstein Veblen, author of The Theory of the Leisure Class (1899), is memorialized in economics by the “Veblen effect,” a term introduced by Harvey Leibenstein to represent a positive consumer demand response to an increase in price. However, Leibenstein’s 1950 QJE article introducing the world to the “Veblen effect” does not cite Veblen as one of its 17 references.I begin this dissertation by revisiting Veblen’s theory of consumer behavior and evaluating its subsequent treatment in the economics literature. I find that Leibenstein (1950) misunderstands Veblen’s concept of “conspicuous consumption” and contradicts Veblen’s empirical predictions.How might Veblen’s theory be interpreted more faithfully with relevance to present-day markets? I suggest that the notion of “Veblen goods” and “Veblen consumers” is misleading, because Veblen’s theories applied to nearly all goods and consumers. My alternative approach is to look for attributes and corresponding prices whose market behavior is in line with Veblen’s predictions. I divide the attributes of goods into three classes, and I suggest that each class has its own hedonic price component: “useful,” “decorative,” and “invisible” attributes.Invisible attributes cannot be detected by the consumer’s own unaided sensory apparatus. Examples of invisible attributes are a good’s market price, scarcity, reputation, ratings, place of origin, microbial content, organic certification, and age. I refer to decorative and invisible attributes, together, as “Veblen attributes”; and I refer to the premiums consumers are willing to pay for Veblen attributes as “Veblen premiums.”In this thesis, I attempt to observe some Veblen attributes and Veblen premiums in present-day consumer markets. I report experimental results from the U.S. retail markets for beer (part II), wine (part III), and food (part IV). I employ a variety of experimental techniques, including consumer surveys, blind tasting experiments, lab experiments, and undercover experiments. I include several first-person essays to round out the narrative.
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Desenvolvimento de cervejas com baixo teor alcoólico com características isotônicas e perfil de cepas com potencial para aplicação na indústria cervejeira. /De Fusco, Deborah Oliveira January 2019 (has links)
Orientador: Gustavo Henrique de Almeida Teixeira / Resumo: ------ / Doutor
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Ispitivanje sadržaja i antioksidativne aktivnosti fenolnih kiselina u toku proizvodnje slada i piva / Investigation of phenolic acids content andantioxidant activity during malt and beer productionPejin Jelena 23 June 2009 (has links)
<p>Cilj istraživanja doktorske disertacije je bio da se u<br />konitnuitetu ispita sadržaj ukupnih fenola, fenolnih kiselina i<br />anitoksidativna aktivnost (antiradikalska aktivnost na DPPH i<br />hidroksil radikale) u toku proizvodnje slada i piva (u ječmu,<br />namočenom ječmu, zelenom sladu, sladu, sladovini, ohmeljenoj<br />sladovini, sladovini tokom fermentacija, mladom pivu i pivu)<br />proizvedenih od tri priznate sorte pivskog ječma: NS 525, NS<br />565 i NS 583.<br />Sadržaj ukupnih fenola u uzorcima ječma je bio: NS 525 -<br />0,76; NS 565 - 0,75 i NS 583 - 0,70 mg GAE/g suve materije.<br />Sadržaj ukupnih fenola u svim proizvednim sladovima (0,96;<br />0,94 i 0,91 mg GAE/g suve materije za NS 525; NS 565 i NS<br />583) je bio viši od sadržaja u ječmu. Sorta NS 525 je imala<br />najviši sadržaj ukupnih fenola tokom svih faza sladovanja, dok<br />su sorte NS 565 i NS 583 imale niže sadržaje ukupnih fenola.<br />Najniži sadržaj ukupnih fenola imala je sorta NS 583.<br />U svim ispitivanim sortama ječma ferulna, p-kumarinska i<br />vanilinska kiselina su bile dominantne u uzorcima ječma,<br />tokom sladovanja i u proizvedenom sladu.<br />Sadržaj ukupnih fenolnih kiselina u ječmu je iznosio za sortu<br />NS 525 - 200,98; NS 565 - 184,10 i za NS 583 – 177,27 μg/g suve<br />materije. Sadržaj ukupnih fenolnih kiselina je rastao kod svih<br />ispitivanih sorti tokom močenja i dostigao maksimum u toku<br />prvog dana klijanja za NS 525 – 548,31; NS 565 – 518,65 i NS<br />583 – 517,17 μg/g suve materije. Dobijeni rezultati su pokazali<br />da je proces sladovanja imao značajan uticaj na sadržaj<br />pojedinačnih i ukupnih fenolnih kiselina.<br />Sorta NS 525 je imala najvišu antiradikalsku aktivnost na<br />DPPH radikale (EC50 za NS 525 - 0,658; NS 565 - 0,667 i NS<br />583 - 0,758 mg/ml) što pokazuje da sorta ječma ima uticaja na<br />antiradikalsku aktivnost na DPPH radikale. Za ispitivane sorte<br />ječma, antiradikalska aktivnost na DPPH radikale se povisila<br />značajno tokom močenja. U proizvedenim sladovima<br />antiradikalska aktivnost na DPPH radikale bila je viša nego u<br />ječmu. Trend porasta i smanjenja antiradikalske aktivnosti na<br />DPPH radikale tokom sladovanja je bio isti za sve ispitivane<br />sorte ječma.<br />Antiradikalska aktivnost na hidroksil radikale, izražena kao<br />EC50 vrednost, u ispitivanim sortama ječma je iznosila: NS 525<br />– 0,352; NS 565 – 0,385 i NS 583 – 0,455 mg/ml. Može se<br />zaključiti da je sorta NS 525 imala najvišu antiradikalsku<br />aktivnost na hidroksil radikale. Antiradikalska aktivnost na<br />hidroksil radikale se znatno povisila tokom močenja. U<br />proizvedenom sladu je antiradikalska aktivnost na hidroksil<br />radikale bila viša nego u ječmu. Trend porasta i smanjenja<br />antiradikalske aktivnosti na hidroksil radikale tokom<br />sladovanja je bio isti za sve ispitivane sorte ječma.<br />Sorta NS 525 je imala najviši sadržaj ukupnih fenola kao i<br />najvišu antioksidativnu aktivnost tj. DPPH i hidroksil<br />antiradikalsku aktivnost. Ovi rezultati pokazuju da sorta<br />ječma može da utiče na antiradikalske osobine slada. Sorta NS<br />525 je imala najviši sadržaj ukupnih fenola, ukupnih fenolnih<br />kiselina i najvišu antiradikalsku aktivnost na DPPH i hidroksil<br />radikale u toku sladovanja.<br />U svim proizvedenim sladovinama, ohmeljenim sladovinama i<br />pivima, ferulna, p-kumarinska, vanilinska i sinapinska kiselina<br />su imale najviše sadržaje. Sadržaj svih ispitivanih fenolnih<br />kiselina je povišen nakon hmeljenja. Najviši ukupni sadržaj<br />fenolnih kiselina je odreñen u ohmeljenim sladovinama (NS<br />525 - 461,41, NS 565 - 426,22 i NS 583 - 423,56 μg/100ml).<br />Sadržaj ukupnih fenolnih kiselina je u svim proizvedenim<br />pivima bio niži u odnosu na odgovarajuće ohmeljene sladovine.<br />U sladovini proizvedenoj iz slada NS 525 je odreñena najviša<br />antiradikalska aktivnost na DPPH i hidroksil radikale što<br />ukazuje da antiradikalska aktivnosti komponenti slada ima<br />uticaja na antiradikalsku aktivnost proizvedene sladovine. U<br />ispitivanim sladovinama, nakon hmeljenja se znatno povisila<br />antiradikalska aktivnost na DPPH i hidroksil radikale.<br />Antiradikalska aktivnost na DPPH i hidroksil radikale se<br />smanjila tokom glavne i naknadne fermentacije.<br />U sladovini proizvedenoj od slada NS 525 sa najvišim<br />sadržajem ukupnih fenola i ukupnih fenolnih kiselina<br />odreñena je najviša antiradikalska aktivnost na DPPH i<br />hidroksil radikale. Tokom proizvodnje piva sadržaj ukupnih<br />fenola se blago smanjio, što ukazuje da je proces proizvodnje<br />imao uticaja na njihov sadržaj. Trend smanjenja<br />antiradikalske aktivnosti na DPPH i hidroksil radikale<br />odgovara smanjenju sadržaja ukupnih fenola i ukupnih<br />fenolnih kiselina tokom procesa proizvodnje piva.<br />Primenjena GC-MS metoda za odreñivanje sadržaja fenolnih<br />kiselina tokom procesa proizvodnje slada i piva se pokazala<br />kao osetljiva, specifična i dobre ponovljivosti. Može se<br />primeniti za odreñivanje sadržaja fenolnih kiselina u ječmu,<br />namočenom ječmu, zelenom sladu, sladu, sladovini, ohmeljenoj<br />sladovini, tokom fermentacije i u pivu.<br />Sadržaj ukupnih fenola, fenolnih kiselina i antioksidativna<br />aktivnost slada, koji se koristi za proizvodnju piva, imaju<br />značajan uticaj na antioksidativnu aktivnost piva.<br />Razumevanje promena sadržaja fenolnih kiselina i<br />antioksidativne aktivnosti tokom proizvodnje slada i piva može<br />nam pružiti vredne informacije o zaštiti endogenih<br />antioksidanata u proizvodnji piva. Na taj način mogu se<br />proizvoditi piva sa višom antioksidativnom aktivnošću i prema<br />tome i povišenom otpornošću prema lipidnoj oksidaciji i<br />starenju piva.</p> / <p>Studies carried out in the frame of the doctorial thesis<br />aimed at continuous determination of the content of<br />total phenolics, phenolic acids and antioxidant activity<br />(antiradical activity on DPPH and hydroxyl radicals)<br />during malt and beer production (in barley, steeped<br />barley, green malt, malt, wort, hopped wort,<br />fermenting wort, green beer, and beer) produced from<br />three accepted brewer’s barley varieties: NS 525, NS<br />565, and NS 583.<br />The total phenolics content in the barley samples was<br />0.76 for NS 525, 0.75 for NS 565 and 0.70 mg GAE/g<br />dry matter (d.m.) for NS 583. Higher content of total<br />phenolics was determined in the malt samples in<br />comparison with the barley samples: (0.96, 0.94, and<br />0.91 mg GAE/g d.m. for NS 525, NS 565, and NS 583,<br />respectively). Variety NS 525 was the highest in total<br />phenolics content during all stages of malting when<br />compared to the other varieties. The lowest content of<br />total phenolics was found in the variety NS 583.<br />In all examined samples, ferulic, p-coumaric and<br />vanillic acid dominated in the barley samples, during<br />malting and in the produced malts.<br />Content of total phenolic acids in the barley samples<br />was 200.98 for NS 525, 184.10 for NS 565 and 177.27<br />mg/g d.m. for NS 583. During steeping, the content of<br />total phenolic acids increased for all samples reaching<br />the maximum at the first day of germination (NS 525 –<br />548.31; NS 565 – 518.65, and NS 583 – 517.17 μg/g<br />d.m.). The obtained results revealed that the malting<br />process had significant impact on the content of total<br />and individual phenolic acids.<br />Variety NS 525 showed the highest antiradical activity<br />on DPPH radicals (EC50 for NS 525 was 0.658, for NS<br />565 0.667, and for NS 583 0.758 mg/ml) indicating that<br />barley variety influences the antiradical activity on<br />DPPH radicals. Antiradical activity on DPPH radicals<br />significantly increased during steeping for all<br />investigated barley varieties. Higher antiradical<br />activity on DPPH radicals was determined in<br />produced malts when compared to corresponding<br />barley varieties. Similar increasing and decreasing<br />trends in the antiradical activity on DPPH radicals<br />during malting were observed in all investigated<br />barley varieties.<br />The antiradical activity on hydroxyl radicals,<br />expressed as EC50 value, in investigated barley<br />varieties, was: 0.325 for NS 525, 0.385 for NS 565, and<br />0.455 mg/ml for NS 583. It can be concluded that<br />barley variety NS 525 showed the highest antiradical<br />activity on hydroxyl radicals. The antiradical activity<br />on hydroxyl radicals significantly increased during<br />steeping. Higher antiradical activity on hydroxyl<br />radicals was determined in produced malts when<br />compared to corresponding barley varieties. Similar<br />increasing and decreasing trends in the antiradical<br />activity on hydroxyl radicals during malting were<br />observed in all investigated samples.<br />Variety NS 525 had the highest content of total<br />phenolics and exhibited the highest antioxidant<br />activity that is antiradical activity on DPPH and<br />hydroxyl radicals. These results suggest that variety<br />can influence the malt antiradical properties. Variety<br />NS 525 was the highest in total phenolics content, total<br />phenolic acids content and antiradical activity on<br />DPPH and hydroxyl radicals during malting.<br />The highest contents of ferulic, p-coumaric, vanillic,<br />and sinapic acids were determined in all wort, hopped<br />wort and beer samples. Increased contents of all<br />phenolic acids were observed after hopping. The<br />highest content of total phenolic acids was determined<br />in the hopped worts (461.41 for NS 525, 426.22 for NS<br />565, and 423.56 μg/100 ml for NS 583. The beers<br />contained less total phenolic acids when compared to<br />the corresponding hopped worts.<br />Wort produced from NS 525 malt showed the highest<br />antiradical activity on DPPH and hydroxyl radicals<br />which indicates that the antiradical activity of malt<br />components affects the antiradical activity in produced<br />wort. After hopping, antiradical activity on DPPH and<br />hydroxyl radicals significantly increased in all worts.<br />The antiradical activity on DPPH and hydroxyl<br />radicals decreased during primary and secondary<br />fermentation.<br />Wort produced from NS 525 malt contained the<br />highest total phenolic content, total phenolic acids<br />content and showed the highest antiradical activity on<br />DPPH and hydroxyl radicals. During beer production,<br />content of total phenolic compounds slightly decreased<br />which indicates that production process had an<br />influence on their content. Similar decreasing trends<br />between the antiradical activity on DPPH and<br />hydroxyl radicals and the contents of total phenolics<br />and total phenolic acids during beer production were<br />observed.<br />The applied GC-MS method for determination of<br />phenolic acids contents during malt and beer<br />production was sensitive, specific and had good<br />repeatability. It can be used for determination of<br />phenolic acids content in barley, steeped barley, green<br />malt, malt, wort, hopped wort, during fermentation<br />and in beer.<br />The content of total phenolics, phenolic acids and<br />antioxidant activity of malt used for beer production<br />have significant influence on the beer antioxidant<br />activity. Understanding how the phenolic acids and<br />antioxidant activity change during malt and beer<br />production can provide valuable information about<br />the protection of endogenous antioxidants in beer<br />production. In this way, the production of beer with<br />enhanced antioxidant activity is possible and therefore<br />higher resistance to lipid oxidation and longer shelflife<br />could be introduced.</p>
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Sledování změn obsahu proteinů lepku v průběhu technologie výroby piva / Changes of gluten proteins during beer processingPorubiaková, Otília January 2018 (has links)
The aim of thesis was monitoring of changes in the content of gluten proteins in the biotechnological process of beer production. During the production process of wheat and barley beer, the samples were collected and analysed using the electrophoresis and immunoassay method. The results of the analyses were compared with commercial Czech beers. The theoretical part contains description and composition of gluten proteins, malt and beer technology, the changes that occur in this process, and methods of gluten proteins analysis. The experimental part contains procedures for laboratory production of barley and wheat beer and analyses of gluten proteins. To identify the individual gluteal protein fraction acid and SDS electrophoresis methods were used. For quantification, enzyme immunoassay was used and evaluated spectrophotometrically. The identification of the gluten‘s fractions by electrophoretic methods has been shown to be less specific for samples with lower content of gluten proteins and for barley specimens. A decrease in the concentration of gliadins and glutenins in the beer production process was demonstrated. A significant change was found during wort production with 98% decrease of gluten content compared to the feedstock and during the fermentation, when the gluten concentration dropped below 10 mg/kg. This value is acceptable from the legislation for products labelled „gluten-free“.
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Sledování obsahu 3-MCPD v ječmeni, sladu a pivu / Monitoring of 3-MPCD content in barley, malt and beerŠálková, Michaela January 2018 (has links)
The master’s thesis focuses on a process contaminant 3-MCPD (3-chloropropane-1,2-diol), which is formed during food processing. The first part of the thesis summarizes scientific knowledge about its chemical and physical properties, toxicity, occurrence in food and methods of analysis. In the second part is monitored the content of 3-MCPD in barley, in standard and special types of malts and beer. Samples were derivatized with phenylboronic acid (PBA) and 3-MCPD derivatives were analyzed by gas chromatography with a mass detector. Deuterated 3-MCPD was used as an internal standard. The limit of quantification was 1 gkg-1 for barley and malt samples and 10 gkg-1 in case of beer. The barley samples contained concentration of 3-MCPD below LOQ. In samples of malt was found concentration
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Podnikatelský plán na založení pivního baru ve městě Olomouc / The Business Plan for Establishing a Beer Bar in OlomoucOhlídal, Evžen January 2019 (has links)
The diploma thesis deals with the business plan for establishing a beer bar with Belgian specials in Olomouc. The first part describes the theoretical basis of the work. It is focused on the description of the business idea, methods used for analytical research of the business surroundings, and the structure of the business plan itself. The second part deals with analytical methods mentioned. Based on these methods, appropriate and most suitable strategy is implemented. The third part of the thesis contains a comprehensive elaboration of the business plan, which follows the choice of strategies for this business.
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Stabilita vybraných mykotoxinů v pivu / Stability of selected mycotoxins in beerŠtáblová, Taťána January 2020 (has links)
Mycotoxins are secondary metabolites of moulds, which attack cereals, for example barley, from which mycotoxins then get to beer. This submitted work is focused on ochratoxin A, deoxynivalenol and zearalenone, which can occur in beer. The first part of this master’s thesis consists of literary research, which describes mycotoxins in general, points out their occurrence, prevention of their formation and delivers information about their physical and chemical properties and toxicity. Furthermore, the research contains basis of malt and beer technology, the occurrence of mycotoxins in beer and raw materials for its production. The research describes changes in concentration of mycotoxins across malt and beer production. The next part deals with possibilities of determination of mycotoxins in barley, malt and beer, compares individual methods of their determination and points out many difficulties of some analyses. The experimental part of this work pursues determination of ochratoxin A, deoxynivalenol and zearalenone in different types of beer with the help of UPLC-FLR, HPLC-MS and ELISA. Instrumental techniques are validated and gathered results are compared with the results in literature. The goal of this master’s thesis is to assess the stability of ochratoxin A and deoxynivalenol in beer over time. The gained results show that there are changes in the concentration of ochratoxin A over time, nevertheless those changes show no pattern. Overall, there was a decrease in concentration in 47 % of the samples and an increase in 28 % of them. In the rest of the samples the concentration did not change. The concentration of deoxynivalenol does not change over time. One of the other goals of this thesis is monitoring of selected mycotoxins in beer. The average concentration of ochratoxin A in the samples was 39 ng/l and deoxynivalenol 9,9 g/l. Zearalenone did not occur in any of the samples when determined by liquid chromatography. All results agree with literature. Next, the thesis compares different analytical methods for determination of ochratoxin A, deoxynivalenol and zearalenone. The screening method ELISA is compared to UPLC-FLR and HPLC-MS. The determination of ochratoxin A by ELISA has shown to be time consuming, nevertheless the results responded to instrumental technique. ELISA overestimated the results of determination of deoxynivalenol in beer by 363–697 % and with zearalenone there were found false positive results.
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Příprava a charakterizace nealkoholického piva s různou příchutí / Preparation and characterization of alcohol-free beers with different flavourBenešová, Pavla January 2012 (has links)
This diploma thesis deals with preparation and characterization of alcohol-free beers with different flavours. Five flavoured and four pure, commercially available beers were tested. Three alcohol-free beers were then selected and used for preparation of flavoured beers. Ingredients used for production of flavour were honey, raspberry, ginger and cranberry. Analysis was focused mainly on substances of phenolic nature. Flavoured beers were also tested in sensory analysis. Ingredients used for flavouring of beers and production of both alcoholic and alcohol-free beers are described in theoretical part of the thesis. Analysis of polyphenols, flavonoids, technological characteristics and anthocyanins was performed using spectrophotometric method. Phenolic substances were identified and quantified by HPLC/PDA. Ascorbic acid was analysed by HPLC-NH2/UV. Results proved an increase of polyphenols, ascorbic acid and anthocyanins during flavouring of alcohol-free beers in dependence of used ingredients. Sensory analysis showed that as the best rated was the Staropramen beer with raspberry flavour. On the contrary, flavoured Bernard beers were poorly rated.
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