SAMMANFATTNING I detta projekt har jag undersökt restprodukten glasmjöl för att ta fram nya potentiella material för designområdet. Jag har arbetat nyfiket och experimentellt för att behålla fokus och intresset vid liv, samt för att fortsätta vara kreativ trots exempelvis stress eller press. Glasmjölet har under projektet processats på olika sätt och blivit ett flertal material med olika egenskaper. Framförallt har jag valt att fokusera på en av processerna vilket var att smälta glasmjölet i 780°C. Detta material blir bland annat poröst, starkt och dekorativt samt skulle med fördel kunna gjutas i en serieproduktion, om det finns gott om restprodukten glasmjöl. Detta återkommer jag till mer under diskussionen.  Under projektet har jag inspirerats friskt av konstverk, design, starka karaktärer och uttrycket ”less is more”, där jag ställer mig kritisk till uttrycket. Två viktiga referenser för mitt arbete har varit Iris Apfel och skulpturen ”Kyssen” av Auguste Rodin som mitt designförslag är mycket inspirerat av. Skulpturen i designförslaget kommenterar uttrycken ”ornament and crime” och ”less is more” där jag istället vill att min skulptur gärna uttrycker ”more is more” där funktionen fokuserar på det dekorativa och skulpturala. Mina slutförslag är tänkta att tänja på gränser och inspirera, samt väcka intresse i syfte att intressenter kan arbeta vidare i materialet för att på sikt ta tillvara på detta avfall som resurs och därmed bidra till en mer hållbar glasindustri, samt möjligtvis även gynna glasindustrin i Sverige. Slutförslagen är också menade att utmana normer kring både estetik och tankesätt som gärna också får väcka ett intresse i sig. För att utforska mitt ämne har jag hållit en workshop, intervjuat ett flertal personer inom design, återvinning och glas. Jag har arbetat på ett intuitivt, strategiskt och konstnärligt sätt. Under projektet var det viktigt för mig att inte begränsas av min kunskap som glasblåsare utan utforska glasmjölet så öppet som möjligt. Jag har använt ohämmade och okomplicerade metoder i den experimentiella fasen som har väckt min nyfikenhet och kreativitet. Därtill har jag tagit strategiska beslut i slutfasen av projektet, för att kunna använda mig av den rika informationen jag har arbetat fram, och sedan göra genomtänkta, relevanta val. För mig har beslutet, att använda intuitionen, rättfärdigat ett sätt att tänka som fungerar bra för mig eftersom det gjorde processen lustfylld, höll mig nyfiken samt möjliggjorde ett snabbare arbetstempo. Det har fått mig att hålla intresset vid liv samt undvika stress i samband med arbetet som skulle kunna göra processen stum. Jag har genom detta förhållningssätt valt att ha alla delar av mitt liv i fokus.

Orientador: Gláucia Maria Pastore / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T17:42:11Z (GMT). No. of bitstreams: 1 Carvalho_DanieleSouzade_D.pdf: 1437090 bytes, checksum: 0180b2360e22ff70ee43cdb53897997b (MD5) Previous issue date: 2011 / Resumo: A produção de compostos de aroma por via biotecnológica é um campo emergente pois diferentemente da tradicional síntese química, os compostos produzidos por micro-organismos são classificados como naturais, indo de encontro à busca dos consumidores por alimentos saudáveis, isentos de aditivos sintéticos. O gênero Neurospora, pertencente a um grupo de fungos filamentosos, é relatado como produtor de hexanoato de etila, um éster caracterizado por possuir intenso um aroma frutal amplamente utilizado na indústria de alimentos. A produção deste aroma por via biotecnológica apresenta ainda alguns entraves, relacionados principalmente ao custo de produção e extração, que podem ser minimizados com o uso de resíduos agroindustriais, diminuindo assim, os custos da etapa fermentativa e tornando-o factível. Considerando que a produção de hexanoato de etila por via biotecnológica é pouco explorada e poucas publicações podem ser encontradas, os objetivos desta tese de doutorado compreenderam o isolamento e seleção de linhagens de Neurospora potencialmente produtoras de hexanoato de etila, em diferentes meio de cultura. Observou-se que o melhor meio sintético foi constituído de 5% extrato de malte e a maior concentração de éster obtida foi mediada pela linhagem Neurospora sitophila GFSC1135. A partir desses resultados foi realizada a otimização do processo de produção de hexanoato de etila visando maior rendimento para possíveis aplicações industriais. Utilizando delineamento composto central rotacional onde os parâmetros otimizados foram: temperatura, agitação, concentração de óleo de soja e inoculo, observou-se um incremento na produção cerca de cinco vezes (45mg.L-1) quando comparado com o primeiro estudo (8mg.L-1). Para os dois métodos de preparo de amostra, extração líquido-líquido e microextração em fase sólida, alguns parâmetros de validação foram determinados visando segurança analítica e credibilidade aos resultados, já que as matrizes são muito complexas. Também foi realizada a otimização do método de extração de hexanoato de etila do meio fermentativo, empregando a técnica de microextração em fase sólida (SPME). Dessa forma, pode-se observar os compostos produzidos pelo micro-organismo, os quais poderiam ser mascarados pelo pico do solvente, quando utilizada a técnica de extração líquido-líquido. Além disso, muitas vezes a concentração dos compostos produzidos é baixa, necessitando de uma técnica mais sensível. De forma semelhante ao realizado com meios sintéticos, a seleção de linhagens foi realizada utilizando resíduos agroindustriais como substrato (manipueira e bagaço de malte), visando minimizar custos relacionados ao meio de cultura, agregar valor ao produto final e suavizar o impacto ambiental gerado por esses resíduos. Comparando-se os resultados obtidos entre o bagaço e o extrato de malte, observou-se que não houve diferença estatística na produção de hexanoato de etila, ficando esta em torno de 45 mg.L-1. Os resultados obtidos mostraram-se promissores, tendo em vista a produção biotecnológica de hexanoato de etila, um éster de aroma impactante e elevado valor agregado, abrindo precedentes aos estudos de elevação da escala de produção e futura aplicação industrial / Abstract: The biotechnological production of aroma compounds is an emerging field and it was stimulated by the increasing preference of alienated consumers for products bearing the label ''natural¿¿. The genus Neurospora belongs to a group of fungus filamentosus, is reported as a producer of ethyl hexanoate and it is characterized by having strong fruity aroma is much used in food industry. The production of this flavor by biotechnological process also presents some difficulties, mainly related to the cost of production and extraction, which can be minimized with the use of agro-industrial waste, reducing costs and making feasible fermentation step. Considering the production of ethyl hexanoate by means of biotechnological processes is rarely explored and few papers can be found, the aims of this research included the isolation and selection of strains of Neurospora potentially producing ethyl hexanoate in different culture media. Observed the best synthetic medium consisted of malt 5% extract and the highest concentration produced by strain Neurospora sitophila GFSC1135. Then the optimization of the production of ethyl hexanoate was carried out in order to increase production to possible industrial applications. Using central composite rotational design where the optimized parameters were temperature, agitation, concentration of soybean oil and inoculum, there was an increase in production about five times (45mg.L-1) compared to the first study (8mg.L -1). For both methods of sample preparation, liquid-liquid extraction and solid phase microextraction, some validation parameters were determined with security and reliability to analytical results, since the matrices are very complex. Was also performed to optimize the extraction method of ethyl hexanoate fermentation media, employing the technique of solid phase microextraction (SPME), because that way, could be observed the compounds produced by microorganism, which could be masked the peak of the solvent, when used the technique of liquid-liquid extraction. In addition, many times the concentration of the compounds produced is low, requiring a more sensitive technique. Likewise, strain selection was accomplished using as substrate (cassava wastewater and bagasse malt) in order to minimize costs related to the culture medium, to add-value to the final product and minimize the environmental impact generated by these agroindustrial residues. Comparing the results between the bagasse and malt extract, it was observed that there was no statistical difference in the production of ethyl hexanoate, it being around 45 mg.L-1.The results were promising of the biotechnological production of ethyl hexanoate, ester of a fruit aroma and high value added, opening previous studies of increased scale of production and its creating opportunity for the industry / Doutorado / Ciência de Alimentos / Doutor em Ciência de Alimentos

Características sensoriais diferenciadas e qualidade química podem garantir a competitividade de uma bebida destilada. O uísque é uma bebida alcoólica produzida a partir da destilação do mosto fermentado de cereais e que passa por um período de maturação em barris de carvalho. A cachaça, por sua vez, é produzida a partir da destilação do caldo de cana-de-açúcar fermentado. O objetivo deste trabalho foi analisar a qualidade química e sensorial da bebida destilada oriunda das matérias-primas cana-de-açúcar e cevada e produzida mediante técnicas já existentes em processos produtivos de cachaça e uísque. O mosto combinado teve como fonte de açúcares o mosto de caldo de cana e o mosto de malte de cevada, que foram preparados separadamente e depois misturados nas seguintes proporções em porcentagem: 100 (A), 75 (B), 50 (C), 25 (D) e 0 (E) de caldo de cana, complementado com o mosto de malte de cevada. O processo fermentativo foi conduzido a 30ºC, mediante adição de leveduras Saccharomyces cerevisiae, cepas CA-11 e S-33, inoculando-se 1,5 g/L de cada levedura. As destilações foram realizadas em alambique de cobre, seguindo a metodologia de dupla-destilação utilizada para a produção de Scotch malt whisky. As bebidas duplamente destiladas foram acondicionadas em barris de carvalho por 60 dias. Os mostos foram submetidos às análises de pH, Brix, Pol, Açúcares Redutores (AR), Açúcares Redutores Totais (ART) e Acidez Total; e os vinhos foram analisados quanto a Teor Alcoólico, pH, Açúcares Redutores Residuais (ARR) e Acidez Total. Os flegmas, bidestilados e as bebidas envelhecidas foram submetidos a análises de teor alcoólico (densitometria), cobre (colorimetria), congêneres voláteis (CG-FID) e carbamato de etila (CG-EM). As bebidas envelhecidas também foram submetidas a análises de intensidade de cor e compostos fenólicos totais (espectrofotometria) e congêneres de maturação (CLAE). Testes sensoriais foram realizados para verificar a preferência entre as amostras pelos consumidores. Análises estatísticas foram realizadas pelo programa SAS (ANOVA e Testes de Tukey). Foi comprovada a eficiência da técnica de bidestilação na redução de alguns compostos limitados pela legislação. Mostos combinados com maior porcentagem de malte de cevada apresentaram menor formação de carbamato de etila. O envelhecimento aumentou a concentração de carbamato de etila nos destilados A, B e C sendo ao final o único contaminante presente acima dos limites permitidos pela legislação de aguardente de cana. Siringaldeído e ácido gálico foram os congêneres de maturação com as maiores concentrações nos destilados. O destilado do tratamento A apresentou a maior concentração total de compostos de envelhecimento. Na análise sensorial o destilado do tratamento C apresentou a maior preferência pelos provadores. Este estudo comprova que a produção de uma nova bebida a partir da combinação de matérias-primas diferentes pode apresentar resultados satisfatórios. Entretanto, ressalta-se a importância da continuidade desse estudo para afinar a definição da combinação de mostos mais adequada, para assim confirmar a viabilidade e eficiência do processo. / Differentiated sensory characteristics and chemical quality can ensure the competitiveness of a distilled beverage. Whisky is an alcoholic beverage produced from the distillation of fermented worts of cereals and aged in oak barrels. Cachaça, in turn, is produced from the distillation of fermented sugarcane juice. The objective of this study was to analyze the chemical and sensory quality of distilled spirit derived sugarcane and barley and produced by existing techniques in production processes of cachaça and whisky. The combined wort had as a source of sugars the sugarcane juice and barley malt wort, that were prepared separately and then mixed in the following proportions by percentage: 100 (A) 75 (B), 50 (C), 25 (D) and 0 (E) of sugarcane juice, supplemented with barley malt wort. The fermentation was conducted at 30° C by addition of Saccharomyces cerevisiae, CA-11 and S-33 strains, inoculating 1,5 g/L of each yeast. The distillations were performed in copper still, according to double-distillation method used for production of Scotch malt whisky. Double-distilled spirits were stored in oak barrels for 60 days. Worts were submitted to analysis of pH, Brix, Pol, Reducing Sugars (AR), Total Reducing Sugars (ART) and Total Acidity; and the wines were analyzed for Alcohol, pH, Residual Reducing Sugars (ARR) and Total Acidity. Low wines, double-distilled spirits and aged spirits were analyzed for alcohol content (densitometry), copper (colorimetry), volatile congeners (GC-FID) and ethyl carbamate (GC-MS). Aged spirits were also analyzed for color intensity and total phenolic compounds (spectrophotometry) and aged congeners (HPLC). Sensory tests were conducted to verify preference between samples by consumers. Statistical analyzes were performed using SAS (ANOVA and Tukey tests). The efficiency of double-distillation technique in reduce some compounds limited by legislation was confirmed. Worts combined with a higher percentage of barley malt showed lower formation of ethyl carbamate. Aging increased the concentration of ethyl carbamate in spirits A, B and C being at the end the only contaminant found above the limits allowed by the cachaça legislation. Syringaldehyde and gallic acid were the aged congeners with the highest concentrations in the spirits. Spirit A had the highest total concentration of aged congeners. Sensory analysis showed that spirit C was the most preferred by tasters. This study demonstrates that the production of a new beverage from the combination of different raw materials can provide satisfactory results. However, it emphasizes the importance of continuing this study to refine the definition of the most appropriate combination of worts, thus to confirm the feasibility and process efficiency.

<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 vi&scaron;i od sadržaja u ječmu. Sorta NS 525 je imala<br />najvi&scaron;i 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 &ndash; 177,27 &mu;g/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 &ndash; 548,31; NS 565 &ndash; 518,65 i NS<br />583 &ndash; 517,17 &mu;g/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 najvi&scaron;u antiradikalsku aktivnost na<br />DPPH radikale (EC50 za NS 525 - 0,658; NS 565 - 0,667 i NS<br />583 - 0,758 mg/ml) &scaron;to 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 vi&scaron;a 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 />&ndash; 0,352; NS 565 &ndash; 0,385 i NS 583 &ndash; 0,455 mg/ml. Može se<br />zaključiti da je sorta NS 525 imala najvi&scaron;u 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 vi&scaron;a 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 najvi&scaron;i sadržaj ukupnih fenola kao i<br />najvi&scaron;u 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 najvi&scaron;i sadržaj ukupnih fenola, ukupnih fenolnih<br />kiselina i najvi&scaron;u 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 najvi&scaron;e sadržaje. Sadržaj svih ispitivanih fenolnih<br />kiselina je povi&scaron;en nakon hmeljenja. Najvi&scaron;i ukupni sadržaj<br />fenolnih kiselina je odre&ntilde;en u ohmeljenim sladovinama (NS<br />525 - 461,41, NS 565 - 426,22 i NS 583 - 423,56 &mu;g/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 odre&ntilde;ena najvi&scaron;a<br />antiradikalska aktivnost na DPPH i hidroksil radikale &scaron;to<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 najvi&scaron;im<br />sadržajem ukupnih fenola i ukupnih fenolnih kiselina<br />odre&ntilde;ena je najvi&scaron;a antiradikalska aktivnost na DPPH i<br />hidroksil radikale. Tokom proizvodnje piva sadržaj ukupnih<br />fenola se blago smanjio, &scaron;to 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 odre&ntilde;ivanje sadržaja fenolnih<br />kiselina tokom procesa proizvodnje slada i piva se pokazala<br />kao osetljiva, specifična i dobre ponovljivosti. Može se<br />primeniti za odre&ntilde;ivanje 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 za&scaron;titi endogenih<br />antioksidanata u proizvodnji piva. Na taj način mogu se<br />proizvoditi piva sa vi&scaron;om antioksidativnom aktivno&scaron;ću i prema<br />tome i povi&scaron;enom otporno&scaron;ću 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&rsquo;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 &ndash;<br />548.31; NS 565 &ndash; 518.65, and NS 583 &ndash; 517.17 &mu;g/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 &mu;g/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>

The diploma thesis deals with proposals of appropriate marketing activities for the company Dalešické cukrářství that are aiming to expand the product in a particular region. The results of these proposals should increase the brand awareness and the growth of sales. The proposals are build on results of analyzes based on theoretical knowledge.

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

This master‘s thesis deals with quantification of vitamin B6 in beverages, food supplements and raw materials in food industry. The literature retrieval part summarizes general information about vitamines, vitamine B6, nicotine acid and vitamine B1. Further on in this part there is described principle of high pressure liquid chromatography and quantification of individual vitamines. In the experimental there are listed used tools, apparatus and chemicals. There is described preparation of idividual samples of food supplements, energy drinks, multivitamine drinks, beers and brewer’s malts. This chapter also contains information about chromatographic separatory systems Shimadzu and SpectraSystem. The quantification was performed by high pressure liquid chromatography on a reverse phase with gradient elution and two ways of detection, fluorescent and spectrofotmetric. The result of experimental activities and vitamine content in analysed samples are presented in the next chapter. In the final contains summarization of results obtained in experimental part. The maser’s thesis was measured in the laboratory of Institute of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology.

The presented thesis deals with the issue of mycotoxins in brewing materials and beer. Attention was devoted mainly to the selected fusarium mycotoxins (deoxynivalenol, zearalenol, T-2 toxin, and HT-2 toxin) ochratoxin A and aflatoxins B1, B2, G1, and G2. The aim of the thesis was to optimize and validate analytical methods for the determination of the above mentioned mycotoxins in the brewing materials and beer. Analytes were separated using high-performance liquid chromatography with mass – spectrometric detection (HPLC-MS/MS) and ultra-performance liquid chromatography with fluorescence detection (UPLC/FLR). These analytical methods were then applied for mapping the occurrence of fusarium mycotoxins in malting barley crops in the Czech Republic and monitoring the level of contamination with mycotoxins in malting and brewing industries. In addition, experiments studying over-foaming of beer were conducted as primary gushing – over-foaming of beer – is connected, similarly as mycotoxins, with the presence of microscopic filamentous fungi in the raw materials for beer production. Studies describing in detail these methods are part of this thesis (Annex I – V). From all published results, it is evident that the occurrence of mycotoxins in cereals including barley is natural and cannot be completely prevented, not even if all conditions of correct agricultural practice are observed. It is known that some mycotoxins present in contaminated malting barley pass to the final product – beer due to their chemical and physical properties. However, the mycotoxin concentrations found do not mean any significant health risk for consumers.

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Due to the high cost of wheat importation in countries where the climatic conditions do not favour its cultivation, alternative sources of bread baking flour are required. Maize is a suitable alternative because it is by far the most important crop produced in Africa. However, it lacks gluten, the protein that is formed in wheat dough which is responsible for the desirable quality attributes (high loaf volume, soft and open crumb structure) of wheat bread. Therefore the need arises to improve maize bread quality. The effects of three types of non-wheat bread methods on the quality of maize bread were investigated. The first was a traditional sourdough method used in Lesotho for making steamed bread. This involved addition of spontaneously fermenting sorghum malt sourdough (equivalent to 15% of the total maize flour) and pre-gelatinization of the starch in the maize flour with boiling water. The second was a Food and Agriculture Organization method which involved pre-gelatinization of the starch in 10% of the maize flour by cooking. The third method was a modern gluten-free sourdough method which involved fermenting 75% of the maize flour with a multiple strains starter culture or Lactobacillus plantarum plus the natural flora in the maize. The modern sourdough method produced maize bread with a more open crumb structure and a significant increase in loaf volume compared to the other methods. This was probably related to the high percentage of fermented maize flour in the recipe, which was probably sufficient to modify the dough properties satisfactorily enough to impact positively on the maize bread quality. Based on these findings, the modern sourdough method was investigated further. Maize sourdoughs were prepared (as described) and compared to chemically acidified maize dough. Sourdough maize bread had an approx. 25-26% increase in loaf volume and a more open crumb structure with large gas cells. This showed that the maize bread quality improvement was not due to low pH. Confocal laser scanning microscopy revealed a cohesive dough structure in the sourdoughs. Larger cells and a more uniform crumb structure were also observed in maize breads with maize sourdough. This indicated an improvement in the maize dough properties with sourdough. Differential scanning calorimetry showed that maize sourdough had a slightly lower peak temperature than straight maize dough, an indication of starch modification. Rheological analysis showed that maize sourdough had a shorter relaxation time, an indication that it was less elastic. Strain sweep analysis revealed that maize sourdoughs had the lowest elastic modulus, also indicating a less elastic dough. Temperature sweep analysis showed an initial less elastic dough and a final high tan delta, suggesting that the maize dough could withstand gas expansion pressure during baking without crumbling. The dominant lactic acid bacteria in the sourdoughs were identified as L. plantarum. In the two sourdoughs, the L. plantarum present were gram-positive, catalase negative and exhibited proteolytic activities. However, only the L. plantarum in the multiple strains starter culture fermented maize sourdough exhibited amylolytic activities. It is proposed that proteolytic activity of the L. plantarum degraded the endosperm protein matrix and hydrolysed the proteins soluble in the dough liquid, thereby allowing increased accessibility of water to the starch granules. It is further proposed that the amylolytic activity of the L. plantarum slightly hydrolysed the starch granules, increasing water absorption by the starch granules. It is proposed that improvement in maize bread quality by sourdough fermentation is due to starch modification (increase water accessibility and water absorption by the starch granules due to the proteolytic and amylolytic activities of the dominant lactic acid bacteria in the sourdoughs) which made the dough less elastic. This in-turn improves the ability of the dough to trap and withstand the pressure of the expanding carbon dioxide in the fermenting dough and bread. / Thesis (PhD)--University of Pretoria, 2014. / gm2015 / Food Science / Unrestricted