Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xiv, 111 p.; also includes graphics (some col.). Includes bibliographical references (p. 104-111). Available online via OhioLINK's ETD Center.

Orientador : Rodolfo Delfino Reyna Benraadt / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos e Agricola / Made available in DSpace on 2018-07-14T17:14:43Z (GMT). No. of bitstreams: 1 Finotelo_NemerAlfredo_M.pdf: 5697467 bytes, checksum: 2a302b57be02239ff24e1616bf555e92 (MD5) Previous issue date: 1981 / Resumo: Devido à importância do leite de búfalas na fabricação do queijo marajoara, enfocamos inicialmente neste trabalho:Origem e classificação zoológica. Raças oficialmente reconhecidas de búfalos domésticos. Características zootécnicas. Aspectos do búfalo no mundo, enfatizando este animal na India, Paquistão, Itália e Brasil. Quanto ao queijo marajoara, além de se estudar as instalações e processamentos em algumas fábricas, foram transportados via aerea para Campinas, amostras do queijo marajoara tipo "creme" e amostras do queijo marajoara tipo "manteiga" de seis diferentes regiões do Estado do Pará, sendo três da Ilha de Marajõ e três do interior. Nestas amostras, com média de sete dias depois de fabricadas, foram realizadas análises químicas e fíSico-químicas, tais como: umidade, extrato seco total, gordura, gordura no extrato seco, pH, proteína, proteína na base seca e cloreto de sódio. Procurou-se portanto determinar a composição deste produto. Com finalidade de se verificar possíveis falsificações nos queijo e através da adição de farinhas ou outros amiláceos, foram feitos testes de identificação de amido em todas as amostras. Na tentativa de inibir o crescimento de fungos, foram feitos testes com vinte e quatro queijos numa pequena fábrica localizada na Ilha de Marajó. Adicionou-se conservadores quimicos em concentrações variadas diretamente à massa durante o processamento em oito queijos e uma hora depois de prontos, cada um deles foi tratado externamente com um produto isolante como: parafina, óleo de linhaça, fórmula desenvolvida pelo I.L.C.T., ou solução inibidora do crescimento de fungos, ficando dois queijos sem nenhum tratamento externo para verificar se apenas o produto conservador adicionado diretamente à massa, seria o suficiente para inibir o crescimento de fungos. Outros quatro queijos, apenas tiveram tratamento externo com um dos produtos já citados e dois meses depois realizaram-se mais duas experiências com outros doze queijos na mesma fábrica, sendo que seis deles foram tratados externamente com o produto isolante de nome Rhodofilm, produziqo pela indústria Bayer do Brasil e o restante foi embalado em sacos plásticos "Cryovac" conforme técnica descrita no Item 6.2. Finalmente, no Laboratório Central de Saúde Pública do Estado do Pará, tendo como base duas pequenas industrias, foram feitas análises microbiológicas do produto acabado e acondicionado na embalagem "Cryovac" com e sem adição de nitrato de sódio e também no produto acabado sem nenhuma proteção como é normalmente comercializado, para efeito de comparaçao no momento que é consumido de acordo com o esquema descrito no item 6.3 / Abstract: Due to the importance of buffalo milk in the manufacture of marajoara cheese, in the present work we first covered: Original and zoological classification. Officially recognized races of domesticated buffalos. Zootechnical characteristics. Aspects of buffalo's in the world with special reference to India, Pakistan, Italy and Brazil. Installations and processes related to the manufacture of marajoara cheese were studied in toco. Besides, samples commercially produced representing six production areas of Pará state, were shipped by air to Campinas; three of the production areas referred to Marajõ Island and the other three referred to inland regions. The samples shipped included the two types of marajoara cheese locally produced: IIcream" type and "butter" type. As far as composition was concerned, the samples shipped ere tested for moisture, dry matter, fat, fat in the dry matter, pH, protein, protein in the dry matter and sodium chloride. To check for possible adulteration such as by intentional addition of flour or other amilaceus products, starch determinations were carried out in alI samples. To inhibit mold growth, several concentrations of different chemical preservatives were tested in twenty four cheeses in a small plant located at Marajo Island. The preservatives were added directly to the cheese mass during the manufacture of eight cheeses. One hour after processing was completed the surface of each of the eight cheeses was treated with an insulating cover including paraffin, linseed oil, and a preparation developed by the Dairy Products Institute Candido Tostes. The surface af two Other cheeses was not treated to serve as controlo Another set of four cheeses were only treated on the surface with one of the products mentianed. Six cheeses were treated with Rhodofilm (Bayer) on the surface and six other cheeses were vacuum packed in plastic cryovac bags according to the technique described in item 6.2. Finally, at the Central Public Health Laboratory of the State of Pará using as reference, two srnall Industrial Plants, were run rnicrobiological analysis of the final product, that was conditioned in cryovac, with and without addition of Sodium Nitrate. Analysis were also done in final product without any protection, as custornarilly commercialized, to compare both, at the moment they are consurned, and in accordance with flowsheet at item 6.3 / Mestrado / Mestre em Tecnologia de Alimentos

Please read the abstract in the section 00front of this document / Dissertation (M Inst Agrar ( Food Processing))--University of Pretoria, 2006. / Food Science / unrestricted

Taken as an engineering material, mozzarella cheese can be considered as a complex food system that has dynamic structure and complex flowproperties. Food scientists have been actively developing methods to characterize mozzarella cheese rheologically, but most of these methods are empirical in nature. In the past decades, there has been a paradigm shift towards the utilization of well-developed rheological methods which have been widely applied in the study of commercial synthetic polymers. In this work, the rheology of mozzarella cheese was studied using well-developed rheological techniques. Utilizing various rheometers, the linear and non-linear rheology of mozzarella cheese was examined. General practical properties of mozzarella cheese such as meltability, flowability and stretchability were extracted from these results. Capillary flow and rolling experiments were also performed to determine their suitability as innovative post-production processing techniques for mozzarella cheese. Finally, a comparative study on the effect of frozen storage on the rheology of three different brands of mozzarella cheese was performed. In general, it was found that mozzarella cheese can be classified as a pseudoplastic (shear thinning) semi-solid material possessing a yield stress at room temperature. Upon heating, the yield stress gradually diminishes and it can be considered as a viscoelastic fluid. The results obtained from the various rheometers indicate that the yield stress, duration of experiment, sample geometry and temperature greatly affect the consistency of the results. It was also shown that extrusion can be used as a processing technique for mozzarella cheese above a certain temperature where the cheese is in a melt state. Rolling was also found to be a potentially feasible processing method. Finally, in terms of the effect of frozen storage, in general, the dynamic moduli decrease with the period of storage due to the freezing of the proteins in the cheese. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

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During the course of ripening, Cheddar cheese frequently develops a flavor defect described as fruity. Recent work has indicated that the use of certain starter cultures ultimately results in the development of the defect as the cheese ages. The flavor compounds responsible for the defect, however, have not been elaborated. The purpose of this investigation was to isolate and identify the components responsible for the fruity flavor defect and to evaluate the role of certain cheese starter cultures in the development of the defect. Since the fruity character of the defect is apparent in the aroma of the cheese, the compounds responsible for the defect were expected to be reasonably volatile. Volatile constituents were isolated by a distillation technique from fat expressed from a typically fruity cheese by centrifugation. The volatile constituents were then separated by gas-liquid chromatography. By monitoring the odor of the effluent stream of the column, it was possible to determine which components had fruity odors, and these were subsequently identified by mass spectral analysis and coincidence of retention time with the authentic compounds. Ethyl butyrate, ethyl hexanoate, and ethyl octanoate were found to be the only compounds with detectable fruity odors. The volatiles from the fat of four cheeses possessing varying degrees of the defect and their matching non-fruity controls were analyzed by a gas entrainment, on-column trapping, gas-liquid chromatographic technique. The manufacturing and curing conditions of each fruity cheese and its matching control were identical, except for the use of different starter cultures. Ethanol, ethyl butyrate, and ethyl hexanoate were more abundant in each of the fruity samples. The approximate concentration range of these compounds was as follows: In fruity cheese; ethanol 400 to 2,040 ppm, ethyl butyrate 1.6 to 24 ppm, ethyl hexanoate 0.9 to 25 ppm. In non-fruity cheese; ethanol 36 to 320 ppm, ethyl butyrate 0.7 to 4.7 ppm, ethyl hexanoate 0.3 to 2.2 ppm. In ten commercial Cheddar cheeses selected at random from the market, the concentration of ethanol ranged from 5.5 to 620 ppm. Single-strain cultures of Streptococcus lactis, Streptococcus diacetilactis, and Streptocococcus cremoris as well as three mixedstrain commercial cultures were evaluated for ethanol and acetaldehyde production in non-fat milk medium. Among the single-strain cultures there appeared to be no correlation between ethanol production and species, although considerable variation was noted for strains within a species. The mixed-strain cultures were designated A, B, and C. Cultures B and C had been implicated in the development of the fruity flavor defect in Cheddar cheese, while culture A produced normal cheese of good quality. Cultures B and C produced approximately 40 times more ethanol than culture A when incubated in non-fat milk medium for one month at 7°C. Certain single-strain cultures and the three mixed-strain cultures were tested for their ability to reduce acetaldehyde and propanal, and to catalyze the formation of ethyl butyrate when ethanol and butyric acid were provided as substrates. Acetaldehyde and propanal were reduced to the corresponding alcohols by all cultures, but the formation of ethyl butyrate was not observed in any culture. A good correlation between high levels of ethanol and high levels of ethyl butyrate and ethyl hexanoate in the fruity cheeses suggests that the quantity of ethanol present in the cheese may determine the amount of ester formed. Further, starters resulting in the defect produced considerably more ethanol than cultures resulting in normal cheese when incubated at 7°C, a normal temperature for curing Cheddar cheese. This observation adds weight to the hypothesis that certain cultures are directly responsible for the defect. / Graduation date: 1966