The wort from the malted barley used in the Scotch Malt Whisky process must be obtained solely from the activity of enzymes associated with the malted barley. Little or no detailed studies have been reported on the complex mixtures of enzymes found in malted barley, nor their subsequent activity and fate within the Scotch Malt Whisky process. The aims of this study were to determine assay procedures for a total of 17 enzymes, ascertain their suitability within the heterogeneous mixture of a malted barley extract and then establish the enzyme activity levels within the production process. Method development of the assay procedures gave rise to specific assays for 13 enzymes. Especially important were those for a-amylase, using the Phadebas substrate, and the I!-nitrophenyl-maltopentaose substrate for β-amylase. Both assays were found to be specific within the complex mixture of malted barley wort, with all other carbohydrase enzymes active. Enzyme activities between malted barley varieties were studied and compared. This suggested that differences occurred between the enzyme levels of varieties, as well as within a single variety. These may be due to malting conditions or to geographical, environmental and/or climatic factors associated with barley cultivation. The activities and fate of the enzymes were followed during the production process. Although the distillery where the study was carried out employed an infusion mashing system, the results obtained may also be valid in the semi-Iauter/lauter type systems used within the industry. Malted barley enzymes were active during the initial stages of fermentation, but thereafter other enzyme systems were evident. These were most likely associated with yeast and bacteria.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-09-13T13:08:07Z No. of bitstreams: 1 2016 - Glenda Ribeiro de Oliveira.pdf: 12901294 bytes, checksum: 80c7709c3b1f78480862304148029e9c (MD5) / Made available in DSpace on 2017-09-13T13:08:07Z (GMT). No. of bitstreams: 1 2016 - Glenda Ribeiro de Oliveira.pdf: 12901294 bytes, checksum: 80c7709c3b1f78480862304148029e9c (MD5) Previous issue date: 2016-08-30 / Four outbreaks of a neurological disease affecting dairy cattle which consumed malted barley waste contaminated with Aspergillus clavatus in the municipalities of Valen?a, Paty do Alferes, and Barra Mansa, in the state of Rio de Janeiro, are described. In all farms, stored malted barley waste exhibited visible fungal contamination and only the animals that ingested the by-product got sick. Animals exhibited muscle tremors, hyperesthesia, ataxia, progressive paresis and paralysis, and marked weight loss. Affected animals were walking with knuckling of hindlimb fetlocks, and some would assume a sitting-dog position. When forced to move around, falls were frequent. There was marked decrease in milk production, even though appetite and thirst remained normal up to the moment of death or euthanasia. Clinical evolution varied from 1 to 16 days. From the animals that recovered, four remained with mild locomotor system sequelae. Morbidity varied between 41.42% and 73.08%, mortality between 33.33% and 69.23%, and lethality between 51.11% and 94.73%. Macroscopic alterations included focal pale areas on the myocardium, semitendinosus, semimembranosus, adductor, pectineus, and Longissimus dorsi muscles. Histopathology was characterized by degenerative-necrotic alterations, tumefaction, vacuolation, and chromatolysis of neurons of cerebellar peduncle nuclei, base of the brain, medulla oblongata, and grey matter of the medulla (the H shape). At histology, muscular lesions were characterized by degeneration and coagulative necrosis, at times with incipient mineralization. In one of the bovines, there was also coagulative necrosis of the myocardium , and presumably, myoglobinuric nephrosis. Fungal culture of samples of malted brewer waste resulted in isolation and identification of A. clavatus. The clinical pathological picture was reproduced experimentally in sheep which consumed 40g/kg of malted brewer waste per day, which was collected from the two investigated farms; these animals developed clinical signs and microscopic lesions similar to those observed in bovines. We conclude that even though brewery by-products have a reasonable cost/benefit ratio for bovine feeding, there is a need to observe steps to avoid eventual poisoning and consequent economical losses / Descrevem-se quatro surtos de uma doen?a neurol?gica que afetou bovinos de aptid?o leiteira que consumiam ?cevada? (baga?o de malte) contaminada por Aspergillus clavatus nos munic?pios de Valen?a, Paty do Alferes e Barra Mansa, no Estado do Rio de Janeiro. Em todas as propriedades, a cevada estocada apresentou vis?vel contamina??o f?ngica e somente os animais que ingeriram o subproduto adoeceram. A morbidade variou entre 41,42% e 73,08%, a mortalidade entre 33,33% e 69,23% e a letalidade entre 51,11% e 94,73%. Os animais evidenciaram tremores musculares, hiperestesia, ataxia, paresia e paralisia progressivas e marcada perda de peso. Os mais afetados caminhavam com apoio sobre os boletos flexionados e alguns assumiam a posi??o de "c?o sentado". Quando os animais eram for?ados a movimentarem-se, as quedas eram frequentes. Houve acentuada queda na produ??o leiteira, embora o apetite e a dipsia tenham se mantido normais at? pr?ximo ? morte ou ? eutan?sia. A evolu??o cl?nica variou de 1 a 16 dias. Dos animais que se recuperaram, quatro permaneceram com sequelas locomotoras leves. As altera??es macrosc?picas inclu?ram ?reas p?lidas focais na musculatura card?aca, m?sculos semitend?neo, semimembran?ceo, adutor, pect?neo e Longissimus dorsi. O quadro histopatol?gico caracterizou-se por altera??es degenerativo-necr?ticas, tumefa??o, vacuoliza??o e cromat?lise nos neur?nios dos n?cleos dos ped?nculos cerebelares, da base do c?rebro, da medula oblonga e do ?H? medular. Histologicamente, as les?es musculares caracterizaram-se por degenera??o e necrose coagulativa, com mineraliza??o, por vezes, incipiente. Em um bovino havia, adicionalmente, necrose coagulativa no mioc?rdio e nefrose mioglobin?rica. O cultivo micol?gico das amostras de cevada resultou no isolamento e identifica??o do fungo A. clavatus. O quadro cl?nico patol?gico foi reproduzido experimentalmente em ovinos que consumiram 40g/kg de cevada por dia, coletada de duas das propriedades investigadas; esses animais desenvolveram sinais cl?nicos e les?es microsc?picas, em grande parte, similares ?s observadas nos bovinos. Conclui-se que embora os res?duos da ind?stria cervejeira tenham razo?vel rela??o custo-benef?cio na alimenta??o de bovinos, ? necess?rio que se observem alguns cuidados para evitar eventuais intoxica??es e consequentes preju?zos econ?micos.