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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.
441

Effect of pH, Fat Level, and Various Browning Agents on Composition, Color, Texture, and Sensory Characteristics of Dark-Cutting Beef Patties

Moiseev, Igor V. 01 May 1997 (has links)
Extra lean (3.3% fat) and lean (20.0% fat) hamburgers in three pH groups (≤ 6.0; 6.01-6.49; 6.50-6.92) were evaluated for cooking-temperature profile, total process lethality, and physical properties after cooking to 71°C by double-side frying on an electric grill. Neither cooking-temperature profile nor cooking time was affected by hamburger fat content or pH. Double-side frying to 71.1°C internal temperature was adequate for more than 6-log destruction of viable E. coli O157:H7 and Salmonella at the geometrical center of extra lean and lean hamburgers. The coldest spot was on the circumferential surface, as indicated by the presence of a red ring of undenatured myoglobin, and confirmed by the finite-element temperature distribution model. The effect of pH (5.80, 6.29, 6.73) on myoglobin denaturation in extra lean (3.3% fat) and lean (20.0% fat) hamburgers was studied. Compared to normal meat (pH= 5.8), raw extra lean ground beef of pH = 6.73 had significantly lower oxidation-reduction potential (ORP) value, lower concentration of metmyoglobin after 48 hr of refrigerated storage, and more distinct cherry-red color. Percent of myoglobin denaturation during cooking was affected mainly by pH and was not affected by total pigment or fat content of hamburgers. A pH ≥ 6.5 and ORP ≤ -200 mV were characteristic of dark-cutting beef In a third experiment, extra lean (3.5%) and lean (20.0%) beef patties were made from normal beef (pH= 5.70) and dark-cutting beef (pH = 6.60). Controls were made with no additives or with 1% salt and 10% added water. Various browning agents (1% glucose, 0.2% caramel colorant, 0.3% calcium peroxide, or 2.5% encapsulated lactic acid) were added with 10% water and 1% salt. Salt had a pronounced prooxidant effect on myoglobin. Distinctive absorption peaks at 541-548 nm and 577-582 nm indicated that the undenatured pigment in cooked patties was oxymyoglobin. Dark-cutting patties had more rubbery texture and slightly perceptible off-flavor. Patties with lactic acid were less juicy and had lower intensity of beef flavor than other patties, and moderate intensity of sour off-flavor. Addition of salt and encapsulated lactic acid to beef patty formulation could solve the problem of hard-to-cook patties.
442

Positive correlation between A3 subunit of glycinin and firmness of tofu made from soybeans grown in three locations over two years

Chen, Ruiqi 10 December 2021 (has links) (PDF)
Producing desirable firmness is important in manufacturing tofu from soybeans. This study’s objective was to explore the environmental impact (location and year) on soybean chemical components and identify the correlations between chemical composition and the firmness of tofu made from soybeans planted in three locations over two years. Seventeen soybean Plant Introductions (PI) from the USDA Soybean Germplasm Collection and eight check varieties were planted in Mississippi, Virginia and Missouri in 2017 and 2018. Protein subunit composition, protein secondary structure, phytic acid content, Ca2+ and Mg2+ content were determined. The result showed that A3 subunit content was strongly correlated with tofu firmness. Environmental factors had a significant influence on some chemical components in soybean seeds as well as tofu texture. The current study confirmed the validity of using A3 peptide as a criterion for estimating tofu firmness in both tofu manufacturing and food-grade soybean trade.
443

Saponin Removal from Quinoa by Abrasion Processing

Lundberg, Luke 01 June 2019 (has links) (PDF)
Quinoa is coated with a thin layer of saponins, glycosylated triterpenoids, that produce a bitter flavor when consumed. The average saponin content in commercial varietals from Bolivia average around 2.7% saponins and organoleptic testing shows the threshold for noticing a bitter flavor is below 0.12% (Medina-Meza et al., 2016). Current industrial processing methods use a combination of abrasion and turbulent water flow to remove saponin. This study will address the following research question: How will grain-to-grain and grain-to-surface abrasion affect the processing time to remove saponin from quinoa? In particular, can effective saponin removal be achieved in less than 10 minutes without washing with water? Three different laboratory scale systems for generating grain-to-grain abrasion alone and in combination with grain-to-surface abrasion were constructed. Preliminary studies using mass balance and visual observation found the tubular system removed 4.45% of the quinoa mass in saponin containing fractions compared to the conical system (1.33%) and fluidized bed (0.62%). After preliminary studies, a saponin estimation method was adapted and the conditions of the tubular system were determined. A randomized experiment was carried out in triplicate at three levels of time (5, 10, and 15 minutes) and mass (200, 300, and 400 grams). The effect of surface roughness in the tubular system was also evaluated. The samples were collected and saponin content in each sample was quantified using the adapted method. The saponin levels were compared to commercially processed quinoa in the market. The processing conditions of 15 minutes at an input mass of 300 grams yielded the lowest saponin level of 0.19%. The four processing conditions of (10 minutes/200 grams, 10 minutes/400 grams, 15 minutes/200 grams and 15 minutes/300 grams) were statistically different (p The tubular system showed promise for reducing process time and saponin content in commercially processed quinoa without washing. However, further experimentation is needed for industrial implementation. The system would provide the industry with a sustainable process with better saponin removal capacity.
444

Evaluation of Chilling Efficiency, Meat Tenderness, and Microbial Analysis of Broiler Carcasses Using Sub-zero Saline Solutions

Viliani, Samira 01 September 2019 (has links) (PDF)
The poultry industry is seeking an advanced chilling system that can improve chilling efficiency, microbial safety, and water consumption without compromising meat quality. The objective of this study was to evaluate the effects of sub-zero saline chilling methods on chilling efficiency, breast fillet tenderness and microbial reduction of broiler carcasses. Following evisceration and rinsing, broiler carcasses were randomly assigned to one of three chilling solutions: 1) 0% salt or ice water control (0% NaCl/0.5oC), 2) 3% salt (3% NaCl/-1.8oC), and 3) 4% salt (4% NaCl/-2.41oC) solutions. Broiler carcasses in sub-zero saline solutions reached the target internal temperature of < 4.4 oC in a faster rate than the 0% salt control, reducing the chilling time by 11% and 39 % for 3% NaCl/-1.8oC and 4% NaCl/-2.41oC solutions, respectively. There was no significant difference in breast fillet pH, regardless of chilling treatment (P < 0.05). However, the breast fillets from sub-zero saline solutions showed higher R-value and longer sarcomere length than those of control fillets (P < 0.05). Breast fillets excised from carcasses in 4% NaCl/2.41oC were significantly tenderized more than the control fillets, with an intermediate tenderness observed for the fillets from 3% NaCl/-1.8oC (P< 0.05). Before chilling, broiler carcasses contained mesophilic aerobic bacteria (MAB), Escherichia coli(E. coli), and total coliforms for 3.81, 0.78, and 1.86 log colony forming unit (CFU)/g, respectively. After chilling, the populations of E. coliand total coliforms were significantly reduced on the carcasses in 3% NaCl/-1.8oC and 4% NaCl/-2.41oCcompared to the control fillets (P< 0.05). There was no significant difference for MAB populations, regardless of treatment. Based on these results, chilling of broiler carcasses in 4% NaCl/-2.4 °C solution seems to be the best choice to improve chilling efficiency, meat tenderness, and microbial reduction compared to the control (0% NaCl/0.5ºC) and 3% NaCl/-1.8oCsolutions.
445

Совершенствование учетно-аналитического обеспечения формирования финансовых результатов на предприятиях пищевой промышленности : магистерская диссертация / Improving the accounting and analytical support for the formation of financial results in the food industry

Мензелеев, М. Х., Menzeleev, M. H. January 2016 (has links)
The purpose of the master's thesis is to study accounting and analytical support for the formation of financial results in the food industry to improve the financial planning business. The relevance of the topic due to the fact that the operation of enterprises in market conditions is a precondition for concentration of attention on the problems of the organization of financial planning and control of financial results, as it affects the financial condition of enterprises and, accordingly, the economic development of the country. Provision of scientific novelty disclosed in this master's thesis: 1) identified and theoretically substantiated the role and place of the formation of financial results across the enterprise planning system, taking into account industry-specific (food industry); 2) an improved form of the "Report on financial results "with elements of the financial analysis, consistent with the objectives of the enterprise. The practical significance of this work is determined in terms of the development of recommendations to improve financial control and forecasting of JSC "Poultry" Sredneuralskaya ", including using methods SWOT and STEP analysis. / Целью магистерской диссертации является исследование учетно-аналитического обеспечения формирования финансовых результатов в пищевой промышленности для совершенствования системы финансового планирования предприятий. Актуальность данной темы объясняется тем что, функционирование предприятий в рыночных условиях является предпосылкой концентрации внимания на проблемах организации финансового планирования и контроля финансовых результатов, поскольку от этого зависит финансовое состояние предприятий, и, соответственно, экономическое развитие страны. Положения научной новизны раскрываемые в настоящей магистерской диссертации: 1) идентифицированы и теоретически обоснованы роль и место процесса формирования финансовых результатов в рамках системы планирования предприятия, с учетом отраслевой специфики (пищевой промышленности); 2) предложена усовершенствованная форма «Отчета о финансовых результатах» с элементами финансового анализа, согласованными с целями деятельности предприятия. Практическая значимость данной работы определяется с точки зрения разработки рекомендаций по совершенствованию финансового контроля и прогнозирования работы ОАО «Птицефабрика «Среднеуральская», в том числе с использованием методов SWOT и STEP анализа.
446

Effects of wet aging on water-soluble flavor compounds, descriptive flavor, consumer acceptability, and willingness-to-pay of beef longissimus lumborum steaks

Wang, Shangshang 08 December 2023 (has links) (PDF)
This study examined the effects of wet aging on water-soluble flavor compounds, descriptive flavor, consumer acceptability, and willingness-to-pay of beef strip steaks. Twenty USDA Select boneless beef loins (NAMP #180) were dorsally divided into four equal portions, which were randomized to receive either 0, 7, 14, or 21 d of wet aging. Short-chained peptide concentration increased from 4.11 mg/g on d 0 to 5.12 mg/g on d 7 (P = 0.011) and subsequently increased to 7.14 mg/g on d 21 (P < 0.001). Cooked beef contained 1.85 mg/g less short-chained peptides than raw beef (P < 0.001). Wet aging for 21 d increased the concentrations of amino acids, which are precursors for the Maillard reaction, including methionine, threonine, cystine, serine, tryptophan, and phenylalanine (P < 0.001). Wet aging decreased the nucleotide concentrations (P ≤ 0.003) and increased hypoxanthine concentration, a compound that imparts bitter flavor (P < 0.001). Flavor intensity of steaks was greater on d 14 than on d 21 (P = 0.009). Steaks that were not aged (d 0) had a more intense umami taste than those aged for 7 and 21 d (P ≤ 0.042); whereas d 7 steaks had less off-flavor, described as metallic, oxidized, and cardboard, than steaks from other aging treatments (P ≤ 0.038). Demand analysis indicated that 14-d steaks would be sold at 5.2, 5.2, and 6.7 units (0.454kg/unit) less (P < 0.001) than steaks aged for 0, 7, and 21 d if holding price constant at $14/0.454kg. Wet aging alters the content of water-soluble flavor compounds in beef, which contributes to flavor development during cooking. Wet aging for 21 d decreased umami taste and flavor intensity. However, amino acid concentrations increased during aging, which contributes to meaty and browning flavors that may be more prevalent in other direct heating methods such as grilling. In addition, results indicated that wet aging for 14 d was not sufficient to provide the flavor and tenderness improvements that were apparent after 21 d of aging since aging beef for 14 d decreased consumer acceptance and demand.
447

<b>Novel Applications of Microbubble Technology for Sustainable Food Processing</b>

Yiwen Bao (8232060) 21 August 2024 (has links)
<p dir="ltr">Global food demand increases rapidly as a result of continuously growing population has raised severe concerns with food security. To overcome this critical challenge, food systems must be transformed to produce food with not only higher yield but also better nutritional quality. Therefore, food processing, as a critical step in food production chain that turn agricultural products into food, needs to be innovated through applications of cutting-edge technologies.</p><p dir="ltr">Microbubbles (MBs) are tiny gas-filled bubbles with distinctive physicochemical characteristics, including slow rising speed and long lifetime in liquid, large surface area per unit of gas volume, high internal pressure, high gas dissolution rate, hydrophobic and negatively charged surface and production of reactive oxygen species. Additionally, MB dispersion can enhance the heat and mass transfer properties of liquid. These features have led MBs to numerous applications in the fields of disease treatment, anaerobic digestion, and wastewater treatment, however, their applications in food processing have not thoroughly explored.</p><p dir="ltr">In this dissertation, MB technology was applied to different unit operations of food processing, including freezing, concentration and extraction, and the effects of MBs on process efficiency and food product quality were comprehensively studied. In the first study, MB-infused freezing medium was used for grape tomato immersion freezing. MBs markedly reduced the drip loss of tomato by 13.7–17.0% and improved its firmness, which were correlated to the accelerated nucleation process and formation of small ice crystals during freezing. The impact of MBs on water evaporation during apple juice concentration was investigated in the second study. MBs dramatically enhanced water evaporation, and concentration at bubble gas temperature of 40 °C and juice temperature of 70 °C showed the largest increase in the evaporation rate, by 104%. Moreover, although air-MBs showed an oxidation effect on both frozen tomato and concentrated juice, N<sub>2</sub>-MBs were found to be an ideal alternative which much better preserved the nutritional values of processed foods. Lastly, MBs and cold plasma-MBs were incorporated into citric acid solution for extracting pectin from apple pomace. MBs present in extracting solvent increased the extraction yield by 18–21%, and extraction with plasma-MBs showed even higher yields by up to 30%. Additionally, MB and cold plasma-assisted extraction were found more effective in extracting complex RG-I pectin.</p><p dir="ltr">This dissertation develops various approaches to incorporating MBs into conventional unit operations and enhancing their performance. With these novel applications explored, MB technology will not only increase the productivity but also reduce the energy, water and chemical use of food processing. Ultimately, MB-assisted processes are expected to play an important role in improving the sustainability of the food industry.</p>
448

Proyecto de inversión para la implementación de una planta productora de pasta de quinua en Lambayeque, 2020

Torres Fernandez, Alix del Rosario January 2021 (has links)
En el presente existe una tendencia por el cuidado de la alimentación, debido a que el consumo excesivo de los alimentos procesados hoy en día es una de las principales causas del sobrepeso. En nuestro país el consumo de pasta se encuentra ubicado en el cuarto lugar, los habitantes están acostumbrados a este consumo dado que cuenta con un precio asequible, tiene una preparación fácil y por eso se encuentra dentro de la canasta básica. Por lo que surge la necesidad de cambiar los componentes de los fideos para aportar los nutrientes necesarios y así reducir el riesgo de sobrepeso y sus consecuencias. Sin embargo, en la ciudad de Chiclayo no se ha implementado una fábrica de producción de fideos a base de quinoa. El propósito de este estudio es determinar la viabilidad del proyecto para la construcción de una planta de fabricación de fideos de quinoa. Como objetivos específicos se tiene, desarrollar el modelo de negocio del proyecto, determinar la viabilidad estratégica del proyecto de inversión, determinar la viabilidad del mercado para la construcción del proyecto, determinar la viabilidad técnica del proyecto de inversión, determinar la viabilidad organizacional del proyecto de inversión, determinar la viabilidad económica y financiera del proyecto de inversión. Como resultados de la presente investigación se obtuvo que, existe una tendencia creciente del sector farináceo, además se pudo evidenciar que diversas instituciones promueven el consumo de una dieta a base de cereales andinos por sus valiosas cualidades con aportes nutritivos, es así que se evidencia una oportunidad para el desarrollo del proyecto aprovechando el dinamismo del sector, dada la preferencia del consumidor por un producto nacional con un alto valor nutritivo. / At present there is a tendency to care for food, because the excessive consumption of processed foods today is one of the main causes of overweight. In our country, pasta consumption is located in fourth place, the inhabitants are accustomed to this consumption since it has an affordable price, it is easy to prepare and that is why it is within the basic basket. Therefore, the need arises to change the components of the noodles to provide the necessary nutrients and thus reduce the risk of overweight and its consequences. However, in the city of Chiclayo, a quinoa based noodle production factory has not been implemented. The purpose of this study is to determine the feasibility of the project for the construction of a quinoa noodle manufacturing plant. The specific objectives are to develop the business model of the project, determine the strategic viability of the investment project, determine the viability of the market for the construction of the project, determine the technical feasibility of the investment project, determine the organizational viability of the investment project. investment, determine the economic and financial viability of the investment project. As results of the present investigation, it was obtained that there is a growing trend in the farinaceous sector, it was also possible to show that various institutions promote the consumption of a diet based on Andean cereals due to their valuable qualities with nutritional contributions, thus, a opportunity for the development of the project taking advantage of the dynamism of the sector, given the preference of the consumer for a national product with a high nutritional value.
449

Proyecto de inversión para la instalación de una planta procesadora de aguaymanto deshidratado al mercado de Alemania 2022

Espinoza Villegas, Milagros Jesus January 2023 (has links)
El presente proyecto denominado “Proyecto de inversión para la instalación de una planta procesadora de aguaymanto deshidratado al mercado de Alemania”, el cual tuvo como objetivo determinar la viabilidad del proyecto desde la colocación de la planta procesadora en uno de los departamentos que produce la mayor cantidad de aguaymanto deshidratado hasta su exportación a uno de los estados más demandantes como lo es Alemania. Para alcanzar este objetivo, se llevaron a cabo varios estudios. Primero, se realizó un análisis de mercado para conocer las perspectivas y preferencias del cliente respecto al producto. Luego, en el estudio técnico, se determinó la capacidad de la planta procesadora. El estudio ambiental evaluó los posibles impactos negativos del proceso completo sobre el producto. Finalmente, el estudio financiero proporcionó información sobre la inversión total y la rentabilidad del proyecto. / The present project, called “Investment project for the installation of a dehydrated aguaymanto processing plant for the German market”, aimed to determine the viability of the project from the placement of the processing plant in one of the departments that produces the largest amount of dehydrated aguaymanto to its export to one of the most demanding states, such as Germany. To achieve this objective, several studies were carried out. First, a market analysis was carried out to learn about the client's perspectives and preferences regarding the product. Then, in the technical study, the capacity of the processing plant was determined. The environmental study evaluated the possible negative impacts of the entire process on the product. Finally, the financial study provided information on the total investment and profitability of the project.
450

Formulações especiais para sorvetes / Specials formulations to ice cream

Silva Junior, Elieste da 07 November 2008 (has links)
A elaboração e caracterização de sistemas tão complexos quanto alimentos não são temas que se esgotem ao longo de um único trabalho. Assim, tomando como ponto de partida o desenvolvimento de formulações para sorvetes, são apresentados os princípios gerais da criação e estabilização de um dos gêneros alimentícios mais apreciados n.o mundo todo. O primeiro capítulo aborda interações que ocorrem entre componentes de uso comum na maioria dos alimentos processados e, de modo específico, o papel desempenhado por cada um deles em formulações para sorvetes. São apresentadas características das matérias-primas especiais empregadas no desenvolvimento das formulações propostas, bem como fundamentos de reologia. Tratam-se os princípios gerais do fenômeno speckle, ferramenta bastante útil em caracterizações estruturais, porém ainda pouco explorada na área alimentícia. O segundo capítulo apresenta as formulações para sorvetes que foram elaboradas para este trabalho e os resultados de caracterizações físico-químicas tomadas sobre alguns dos ingredientes utilizados, bem como sobre os produtos finais desenvolvidos. O terceiro capítulo exibe os resultados das avaliações reológicas feitas em ingredientes e misturas formuladas para este estudo. A partir do perfil demonstrado pelos reogramas, interações microscópicas puderam ser cogitadas. Mostram-se também, imagens tomadas por um sistema de videomicroscopia acoplado ao reômetro (módulo Rheoscope), onde puderam ser observadas deformações estruturais em tempo real ocorridas com as amostras durante as avaliações. O quarto capítulo propõe uma nova metodologia de investigação estrutural na qual a análíse dos resultados gerados a partir de um fenômeno de interferência possibilita mapear a evolução da microestrutura de sorvetes ao longo do tempo, quando submetidos a diferentes condições de temperatura. / Elaboration and characterization of systems with high leveI of complexity as foods cannot discussed in an only study. In this work, from development of special ice cream formulations are presenteei the general principIes of creation and stabílízation of one of the most appreciated foodstuffs. In first chapter the interactions that occur among components of current/y use in processed foods and, in a specific manner, the role of each one in ice cream formulations. Characteristics of the special raw materiais employed in development of the proposed formulatíons are presenteei, as well fundamental concepts of rheological behavior. Also, general principies of speckle phenomenon are presented, a very useful tool to structural investigations in several systems, but few explored in food science and technology. In second chapter are presented the ice cream formulations that were elaborated by this research and the results of analysis of both composition and chemical properties taken on some ingredients as well in developed products. In third chapter are exhibited the results from rheological assessments performed in ingredients and formulated ice cream mixes. From rheological curves, microscopic interactions could be cogitated. Images taken by a system of microscopy connected to rheometer shown structural deformatíons in real time occurred with the samples during the evaluations. In fourth chapter is showed a new methodology of structural investigation in which the analysis of results obtained from interference phenomenon allow to generate a map of temporal evolution of ice creams along the time, at different temperature conditions.

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