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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Resource substitution: automatic casing and stacking versus manual casing and stacking of fluid milk products

Schad, James Edward January 1963 (has links)
A study was conducted to determine the break-even point of three comparative fluid milk casing and stacking operations. The first comparative models consisted of two filling machines with the processed cartons manually cased and stacked, compared with automated casing and stacking, on a cost basis. The second comparative models consisted of three filling machines with the processed cartons cased and stacked as in the first comparative models. The third comparative models consisted of four filling machines with the processed cartons cased and stacked as in the first and second set of models. The break-even point of the first comparative models was not reached within a 24 hour period based on 260 operating days per year. However, components of automation in the packing handling phase of the fluid milk plant operation were considered. The break-even point of the second comparative models was reached after 18-1/2 hours of operation. It is advisable for the operator of this combination of filling equipment to consider automation if he is operating the plant more than 18-1/2 hours per day. If this is not feasible, then those components of automation should be considered that would result in the greatest reduction in the packing handling costs of the processed milk. The break-even point of the third comparative models was reached at slightly over seven hours of operation. The operator will realize a savings by installing the automated equipment if it is operated at or above seven hours per day. / Master of Science
142

The effects of the federal programs on the U.S. dairy industry

Bark, Pyengmu January 1988 (has links)
Milk surplus in the U.S. dairy industry has been increasing substantially since the beginning of the 1980s. In order to analyze the surplus production situation, an interregional dairy trade model based on a spatial equilibrium framework was developed. The model included disaggregate manufactured milk markets and utilized separable programming as the solution technique. The objective of the interregional dairy trade model was to maximize the sum of producers’ and consumers’ surplus subject to the various institutional constraints incorporating unregulated and regulated market situations. Under the regulated market situation, the institutional constraints were based on the federal milk marketing order and dairy price support programs. Utilizing the interregional dairy trade model, a comparison of simulated market results and net economic effects between unregulated and regulated markets was drawn first. Results of the simulations for market results and welfare effects under pricing policy options with regard to changes in the support and purchase prices were also analyzed. Finally, a comparison of the results of simulations for simultaneous market clearing situations in butter and nonfat dry milk markets with no government purchases of these commodities under the 1982 market situation and an increasing quota system was considered. It was found that without considering the supply effect induced by price stabilizing regulations, the competitive manufactured milk market price would be lower than the 1982 support price level. The butter and nonfat dry milk markets would move toward a market clearing situation if the support price level was decreased by $1.00 per cwt for butter and by $2.00 per cwt for nonfat dry milk when cross price elasticity effects were included. Due to cross price elasticity effects, the butter market would clear at a higher price level (in terms of the support price) than the nonfat dry milk market. Simulations of simultaneous market clearing situations suggested that the 1982 butter price would be lower and the nonfat dry milk price would be higher than market clearing prices. Increases in import quotas would drop butter and cheese market clearing prices and raise the nonfat dry milk price relative to the actual 1982 case. / Ph. D.
143

The White Stuff: Milking in the Outer Scottish Isles

Bond, Julie, Mulville, J., Craig, O.E. January 2005 (has links)
No
144

Calving seasonality at Pool, Orkney during the first millennium AD: an investigation using intra-tooth isotope ratio analysis of cattle molar enamel

Towers, Jacqueline R., Mainland, Ingrid L., Montgomery, Janet, Bond, Julie 06 January 2016 (has links)
Yes / The identification of dairying is essential if we are to understand economies of the past, particularly in northwest Europe, where a high degree of lactose tolerance suggests that fresh milk has long been a significant food product. This paper explores a possible link between economic focus and seasonality of calving. Although cattle (Bos taurus) can breed throughout the year, animals living in temperate regions with minimal or no human management tend to breed seasonally, their breeding behaviour being strongly influenced by the availability of food. In order to achieve a year-round supply of fresh milk in the past, it is likely that multiple-season calving was necessary, which would have required additional husbandry effort. Alternatively, for meat-focussed economies or those based on storable dairy products, a strategy of single-season calving in spring may have been favoured to maximise the utilization of spring and summer vegetation. Cattle birth seasonality is investigated through isotope ratio analysis (δ18O, δ13C) of tooth enamel. Results for cattle from Pool, Orkney dating to the latter part of the first millennium A.D suggest that calving occurred during at least three seasons implying that the continuous provision of fresh milk was of economic importance. / AHRC Studentship
145

A calf for all seasons? The potential of stable isotope analysis to investigate prehistoric husbandry practices

Towers, Jacqueline R., Jay, Mandy, Mainland, Ingrid L., Nehlich, O., Montgomery, Janet 2011 March 1930 (has links)
Yes / The Early Bronze Age barrows at Irthlingborough and Gayhurst in central England are notable for the large number of cattle (Bos taurus) remains associated with their human Beaker burials. Previous work using strontium isotope analysis has indicated that most of the cattle analysed, and one aurochs (Bos primigenius), were of local origin (Towers et al. 2010). In this study, stable isotope analysis of enamel and bone was carried out to investigate whether the mature cattle had experienced similar husbandry practices, climate and environment. Bulk carbon, nitrogen and sulphur isotope analysis of collagen suggested most were consuming similar sources of plant protein from environments probably local to the sites and this was supported by high resolution intra-enamel carbon isotope profiles. Oxygen isotope profiles indicated the aurochs and most of the cattle experienced similar climatic regimes: the only exception being an animal with a non-local strontium isotope ratio. However, a comparison of seasonality profiles of the local animals using estimated tooth formation times showed that there was no consistency in season of birth: the animals appeared to have been born throughout the year. Cattle can breed throughout the year but it requires considerable human effort and intervention to successfully overwinter young stock; it is therefore unlikely to have been carried out without good reason and benefit if winters were harsh. One reason is to ensure a continuous supply of milk. Measuring oxygen isotope profiles to identify year-round calving may thus be a potential indicator of dairying economies.
146

Feasibility study for a Tillamook County dairy waste treatment and methane generation facility

Edgar, Thom G. 08 November 1991 (has links)
With the expansion of the Tillamook Creamery, in Tillamook Oregon, to double or more its cheese production, the demand for milk presents an economic opportunity for the member dairies of the Tillamook County Creamery Association. Before area dairies can expand their herd size to increase milk production for the creamery, the problem of manure waste management and pollution control must be solved. This study considers the technical and economic feasibility of developing a centralized waste treatment and methane generation facility to treat manure generated by Tillamook County dairies. A computer program modeling animal waste anaerobic digester design served as the basis for generating cost and production estimates for several hypothetical scenarios assuming input data specific to the Tillamook situation. A follow up study was also made to determine the variability of the potential ultimate methane yield of manures from Tillamook dairies. This study indicates that the proposed system is technically feasible. The study estimates that a comprehensive treatment system could cost dairymen from $70 to $100 per cow per year to start, but the economic feasibility improves as more manure is treated and more dairies participate. A full scale system has the potential to break even economically from the sale of electricity produced by a 5 megawatt methane powered generator. With the marketing of treated solids as a high grade fertilizer the system could gross a return of $1 to $75 per cow per year, depending on the scenario. / Graduation date: 1992
147

Constraints on smallholder dairying in Swaziland : Manzini Region & surrounding areas.

Malima, Boyce Thabo. January 2005 (has links)
Summary: Swaziland has long had a disparity between the supply and demand of milk. Even at present milk production continues to be less than the market demand. The quantitative contribution of smallholder dairy farmers to local milk production remains unknown because of poor record keeping. This study was aimed at attaining a clear understanding of the dynamics of smallholder dairying in Swaziland, including the identification and understanding of the constraints faced by farmers in dairying, with the hope of devising workable solutions to them. A sample of 118 smallholder dairy farms were covered in this study, with a total herd of 306 lactating cows, comprising mainly of Jerseys and Holstein Friesians, with some cross breeds. There were no significant differences in mean milk yield/cow with respect to farmer gender (P > 0.05) and Agro-ecological zone location (P > 0.05) of the farms. Milking frequency had a significant effect on milk yield, since cattle milked once a day had lower (P < 0.05) milk yields than those milked twice a day. The cattle had extensively long calving intervals i.e. 448 ± 166 days, ranging from 292 to 1082 days. Low milk yield and poor reproductive performance of cattle were found to be mainly due to poor nutrition, breeding practices and stock quality. These are primarily a result of insufficient farmer training and inadequate technical assistance, scarce availability of quality stock, lack of investment resources and market support that includes favourable milk prices for farmers to make money. This performance of the Swazi smallholder dairy herd was then evaluated by comparing it to the performance of a larger, well-managed herd of known pedigree. Lactation records from 252 Jersey cows and 108 Holstein Friesian cows were obtained from Cedara Agricultural Research Institute, covering the periods; July, 2002 to July, 2004 and November, 2002 to April, 2004, respectively. Cows were grouped by parity and calving season and the gamma function proposed by Wood (Y = An(b) e(-cn)) was used to fit standard lactation curves on group data. The curve parameters A and b increased with parity, while that of c and s (persistency of lactation at peak) decreased, producing standard lactation curves save for the Holstein Friesian summer calvers, which produced atypical curves. The R(2) values (goodness of fit) increased with parity. Animal parity and calving season were found to influence the peak and shape of the lactation curves and their parameter estimates. The performance of the Swazi smallholder herd showed a mean deviation of the observed daily milk yield of the Holstein Friesian breed from the expected yield to be - 3.47 (SD 6.052) kg and that of the Jersey breed was - 16.92 (SD 5.473) kg. The mean proportional deviation of observed milk yield from the expected yield for the Holstein Friesian breed was - 0.3 (SD 0.37) and that of the Jersey breed to be - 0.6 (SD 0.19). The proportional milk yield deviation of the Holstein Friesian breed can be explained using the equation Y = O.1322(SE = 0.1293) x - 2.3581 (SE = 0.20639), where x = expected milk yield and Y is the proportional deviation of the observed milk yield deviation from the expected milk yield. With respect to the smallholder Jersey breed, no relationship was found that could explain the proportional milk yield deviation. The smallholder herd was shown to be underperforming, considering the potential for higher milk yields of the two breeds. In the quest to gain a greater understanding of the dynamics of smallholder dairying, the sample of 118 farmers was further analysed using multivariate statistics to categorise them based on their herd sizes, herd structures, management and success perceptions in dairying. The analysis produced three clusters (categories): cluster 1 had the largest herd sizes and poor milk production efficiency; cluster 2 had intermediate herd sizes, the highest number of farmers and more efficient milk production per cow. This cluster, however, had the highest proportion of calf mortalities. Cluster 3 had the smallest herd size, the lowest calf to cow ratio and the second highest calf mortality. Record keeping across all clusters was very poor and the average milk yield per cow was generally low. Most of the farmers do not appreciate the importance of annual calving of their cows as an integral part of the success of their dairy projects and winter feed supplementation is very poor across all the clusters. There remains a great need for the enlightenment of the farmers on the importance of good nutrition, breeding, calf rearing and record keeping in successful dairying. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
148

Sistema de ultra-som para caracterização de leite bovino

Dorabiato, Luiz Fernando 23 November 2007 (has links)
CAPES; CNPq / Este trabalho apresenta o projeto, desenvolvimento e testes de um sistema de caracterização de leite bovino por ultra-som. Analisadores comerciais de leite bovino são utilizados em cooperativas e laticínios a fim de avaliar a qualidade do leite entregue pelos produtores. Entre as características avaliadas estão a quantidade de gorduras, extrato seco desengordurado e água adicionada ao leite. Estes índices são utilizados para estimar o rendimento da produção de laticínios e adulteração do leite. O sistema desenvolvido bombeia a amostra a ser analisada para o interior de uma célula de testes, que é aquecida a fim de fazer medições sob temperatura conhecida. Em seguida, o sistema adquire o valor da amplitude e tempo de propagação do pulso de ultra-som na amostra e relaciona estes parâmetros acústicos a valores de gorduras, extrato seco desengordurado, proteínas e água adicionada nas amostras de leite. O sistema tem boa reprodutibilidade, apresentando baixo Coeficiente de Variação (inferior a 8,8%) para análises dos componentes sólidos do leite – gorduras, proteínas e extrato seco desengordurado. Os testes de calibração apresentaram coeficientes de determinação entre os parâmetros acústicos (atenuação e velocidade de propagação) e os parâmetros a serem avaliados (teor de gordura, extrato seco desengordurado, proteínas e água adicionada) superiores a 97 % (R2 > 0,97), com erros padrão de estimativa inferiores a 1,25%, indicando baixa dispersão dos dados experimentais em relação às curvas de regressão. Para avaliar o protótipo desenvolvido, foram realizados testes comparativos com equipamentos de referência. Foram utilizadas amostras de leite proveniente de um único fornecedor. Apesar do pequeno número de amostras/fornecedores avaliados, os erros percentuais absolutos máximos obtidos para as análises de componentes sólidos foram de 12,6% para gordura, 12,37% para proteínas e 13,76% para extrato seco desengordurado. Já para a quantidade de água adicionada, os erros foram superiores a 40%, no entanto estes erros deverão ser reduzidos utilizando-se um conjunto maior de amostras/fornecedores durante o processo de calibração e avaliação final do protótipo desenvolvido. Os resultados preliminares obtidos permitem concluir que o sistema de ultra-som desenvolvido é adequado para a determinação dos principais componentes do leite bovino. / This work presents the design, development and tests of an ultrasonic milk analyzer. Milk analyzers are employed by dairy industry to evaluate the quality of acquired milk. Some of the assessed features are the fat content, solids non-fat and added water to the milk samples. These features are employed to estimate the production income of dairy products and milk adulteration. The system pumps a sample to the test cell, then the cell is warmed and the measurements are done at known temperature. Then, the system acquires the amplitude and the propagation time of the ultrasound pulse through the sample and correlates these acoustic parameters to the fat content, solids non-fat, proteins and added water in milk samples. The system showed good reproducibility, presenting low coefficient of variation (lower than 8.8%) for analysis of solid content in milk samples – fat, proteins and solids non-fat. The calibration tests presented determination coefficients between the acoustic parameters (attenuation and propagation time) and the milk components (fat content, solids non-fat, proteins and added water) higher than 97% (R2 > 0.97), with standard error of estimate lower than 1.25%, showing low dispersion of the experimental data in relation to the regression curves. To evaluate the developed prototype, comparative tests in milk samples of only one supplier were carried out using the prototype and reference equipments. In spite of the small number of samples evaluated, the maximum absolute percent errors obtained for the analysis of solid content in milk were 12.6% for fat content, 12.37% for proteins and 13.76% for solids non-fat. The percent errors obtained for the amount of added water were higher than 40%, however these errors should be reduced using a higher number of samples/suppliers during the final calibration/evaluation process of the developed prototype. The preliminary results allow to conclude that the ultrasound system developed is adequate to quantify the main components of bovine milk.
149

Avaliação das características físico-químicas e alterações do leite UHT (UAT) produzido no Estado de Goiás ao longo da estocagem / Avaliação das características físico-químicas e alterações do leite UHT (UAT) produzido no Estado de Goiás ao longo da estocagem

COSTA, Andréia Di Martins Carmo 14 May 2010 (has links)
Made available in DSpace on 2014-07-29T15:22:53Z (GMT). No. of bitstreams: 1 DISSERTACAO ANDREIA DI MARTINS CARMO COSTA.pdf: 1006144 bytes, checksum: 227af4777a5b21b55e55f1d21e9c9eab (MD5) Previous issue date: 2010-05-14 / With the objective of evaluating the physical/chemical, microbiological characteristics and the changes that occur in UHT milk (UAT) processed in the State of Goias during its storage for 135 days, a study was done between August and December 2008 with all the companies that produced UHT milk (UAT) processed in the State. Samples were collected from refrigerated raw milk stored in milk storage silos of industry for analysis of their physical/chemical and microbiological characteristics. From each company, twelve one liter cartons of milk were collected for analysis of their physical/chemical and microbiological properties as well as nitrogen compounds and the amount of fat separation from the milk and sedimentation within each sample. The samples were sent to the laboratories of Microbiology and Dairy of the School of Agronomy and Food Engineering at the Federal University of Goias (UFG). The physico-chemical properties of raw milk were in accordance with the parameters established by legislation, except for three brands of milk, with values of freezing point, nonfat milk solids and total solids. The Alizarol test results were normal for UHT milk (UHT) of all brands, except the milk of the mark "E", which has had worst results established by legislation. All milk samples were within the standards for titratable acidity and pH. The density indices were normal, but decreased during the stock. The freezing point values were within the standards, but increased during the storage and the values of total solids and nonfat solids were low and at variance with the laws in UHT milk (UHT) of all brands. The fat found below the minimum content of 3% recommended by the legislation. All results are suggestive of water being added accidentally during processing. Scores were found higher than those established by law for psychotropic and mesophilic aerobic refrigerated raw milk. In UHT milk (UHT) milk from only one mark was at odds as the parameters established by law for heat resistant spores of aerobic mesophiles. It was verified a progressive increase in sedimentation and fat separated from milk during storage and observed age gelation in milk from one brand to 135 days of storage. From the results obtained can be verified that the physicochemical characteristics of UHT milk (UAT), when compared to raw milk source, changed negatively and that the raw material, the type of thermal processing and storage time at room temperature are possible causes for the changes that occurred throughout the shelf-life UHT milk (UAT). / Com o objetivo de avaliar as características físico-químicas, microbiológicas e alterações que ocorrem em leite UHT (UAT) processado no Estado de Goiás, durante seu armazenamento foi feito um estudo entre agosto e dezembro de 2008, por 135 dias, com leite UHT (UAT) de todas as marcas processadas no Estado. Foram coletadas amostras de leite cru refrigerado nos silos de estocagem de leite das indústrias, para análises físico-químicas e microbiológicas. Foi feito o acompanhamento do processamento do leite desse mesmo silo pelo sistema UHT (UAT). De cada indústria foi coletado um pacote embalado, contendo doze caixas cartonadas de um litro de leite, para análises físico-químicas, microbiológicas, teor de compostos nitrogenados e para verificação de ocorrência de sedimentação e de gordura separada do leite. As amostras de leite cru refrigerado foram colocadas em caixas isotérmicas contendo gelo e as amostras do leite UHT envasado foram encaminhadas aos laboratórios de Microbiologia e de Laticínios da Escola de Agronomia e Engenharia de Alimentos da Universidade Federal de Goiás (UFG). As análises físico-químicas do leite cru se apresentaram de acordo com os parâmetros preconizados pela legislação, com exceção do leite de três marcas, com valores de crioscopia, extrato seco desengordurado e extrato seco total. Ao longo do período de estocagem os resultados das análises de Alizarol apresentaram-se normais para o leite UHT (UAT) de todas as marcas, com exceção do leite da marca E , sendo esse leite o que teve mais resultados fora dos padrões estabelecidos pela legislação. Todas as amostras de leite estavam dentro dos padrões para acidez Dornic e pH. Os índices de densidade estavam normais, mas decresceram durante o estocamento. Os valores de crioscopia estavam dentro dos padrões, mas altos e os valores de extrato seco total e extrato seco desengordurado apresentaram-se baixos e em desacordo com a legislação no leite UHT (UAT) de todas as marcas. Os teores de gordura se apresentaram abaixo do teor mínimo de 3% preconizado pela legislação. Os resultados em conjunto são sugestivos de adição de água durante o processamento. Foram encontradas contagens superiores aos estabelecidos pela legislação para bactérias psicrotróficas e Aeróbios Mesófilos no leite cru refrigerado. No leite UHT (UAT) apenas o leite de uma marca estava em desacordo com os parâmetros preconizados pela legislação para esporos termorresistentes de Aeróbios Mesófilos. Foi verificado aumento progressivo de sedimentação e de gordura separada do leite durante a estocagem e observada gelificação no leite de uma marca aos 135 dias de estocagem. Conclui-se que as características físico-químicas, do leite UHT (UAT), quando comparadas ao leite cru de origem, se alteraram negativamente e que a matéria-prima, o tipo de processamento térmico e o tempo de estocagem em temperatura ambiente são possíveis indicativos da origem das modificações ocorridas ao longo da vida-de-prateleira do leite UHT (UAT).
150

Srovnání kvality mléka jako potravinové suroviny z konvenčních a ekologických hospodářských podmínek / Comparison of quality of milk from conventional and organic farming

Cermanová, Ivana January 2011 (has links)
The diploma thesis focuses on the comparison of milk quality in two different ways of farming, conventional and organic farming. Almost a hundred parameters on the set of 64 bulk milk samples were monitored. The theoretical part of the paper describes the composition of cow's milk, its technological and hygienic properties and it notes the nutritional impact of milk and milk products. It also mentions the most important legal definition of organic farming. Experimental part describes the setting of the experiment and mentions the methods used to analyze milk samples for individual parameters and it details the ten selected determination. The difference in measured values of various milk indicators depending on the dairy farm was observed by using statistical methods and an explanation was suggested in the case of the statistical significance. The thesis was based on the cooperation of the Faculty of Chemistry VUT Brno and a National reference laboratory for raw milk at the Research Institute for Cattle Breeding in Rapotin.

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