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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.
61

Desenvolvimento de formulação para bolo contendo farinha de maca e yacon / Development of a formulation for chocolate cake with maca and yacon flours

Tormena, Marcela Marta Lazaretti 18 April 2016 (has links)
CAPES / Neste trabalho foi desenvolvida uma formulação otimizada de bolo de chocolate com substituição parcial da farinha de trigo por uma mistura de farinha de yacon e maca peruana. Os tubérculos escolhidos são alimentos com propriedades funcionais benéficas à saúde, como ação antioxidante e efeito prebiótico. A influência das proporções das farinhas e a quantidade de água acrescentada à massa foram avaliadas através de análise sensorial, colorimetria, perfil de textura e volume específico. Foi aplicado um planejamento experimental do tipo simplex-centroid, para as proporções das três farinhas, com a quantidade de água como uma variável de processo avaliada em três níveis distintos. De acordo com os resultados do atributo aceitabilidade geral dos bolos, os julgadores foram segmentados em dois grupos pela técnica do k-means. Após a segmentação foram construídos modelos de regressão para aceitabilidade geral média de cada grupo sendo obtido valores de R2ajustado de 92,5 % para o grupo 1 e 98,9 % para o grupo 2. Através da otimização pelo método simplex sequencial foi determinada uma formulação otimizada para o grupo 1 (49 % de trigo, 37 % de yacon, 14,0 % de maca e 140,0 mL de água) e outra para o grupo 2 (35 % de trigo, 65 % de yacon, 0,0 % de maca e 120,0 mL de água). Além dessas formulações, foi proposta uma terceira mistura com o maior teor de maca (32 %) que não alterasse significativamente a aceitação geral de ambos os grupos. De maneira geral, os resultados da avaliação sensorial indicaram que a presença do yacon aumenta o grau de aceitação do bolo, mesmo com a adição da maca que se mostrou sensorialmente menos aceita. Foi identificada uma correlação significativa entre a aceitação geral dos bolos e seu sabor. Assim também, a cor sensorial foi diretamente relacionada a bolos mais escuros e com maior saturação do marrom. As três formulações otimizadas em conjunto com duas formulações controle foram utilizadas em uma análise de perfil livre. Os resultados da análise de perfil livre foram submetidos à análise de componentes comuns com pesos específicos, cujos resultados, na forma de um gráfico de consenso e de saliências, tornaram observáveis os efeitos diretos da substituição do trigo pelo yacon e pela maca, sobre as propriedades sensoriais dos bolos produzidos. A correlação das componentes comuns com os atributos dos julgadores foi utilizada para a descrição sensorial das amostras. Assim, uma maior proporção de maca intensifica a cor marrom, o aroma e sabor de queimado. Já uma maior proporção de yacon produz uma melhor aparência, maciez, sabor doce e de chocolate. Isto corrobora a afirmação que a substituição do trigo pelo yacon nos bolos produzidos traz melhorias às suas características sensoriais, enquanto a adição de maca traz prejuízos sensíveis às mesmas. / This work describes the development of an optimized chocolate cake formulation with partial substitution of wheat flour by a mixture of yacon flour and maca flour. The chosen tubercles are functional foods with benefits to human health, as antioxidant activity and prebiotic effect. The influence of the proportions of the flours, as the amount of water added to the batter, were evaluated through the results of sensory analysis, colorimetry, texture profiling and specific volume. The simplex-centroid experimental design was proposed for the three mixture variables (flours proportions) and one process variable (amount of water added to the batter) in three distinct levels. The consumers were segmented through the k-means technique, grouped by their overall acceptability of the cakes. A regression model for the overall acceptability was constructed for both groups, with a R2adjusted of 92.5 % for group 1 and 98.9 % for group 2. The sequential simplex method was used to optimize the formulation for group 1 (49 % wheat, 37 % yacon, 14 % maca and 140 mL of water) and, group 2 (35 % wheat, 65 % yacon, 0 % maca and 120 mL of water). It was proposed a third formulation with greater maca content (32 %) and minimal effect on overall acceptability for both groups. In general, the sensory evaluation results indicated that the presence of yacon increases the acceptability of the cakes, even when maca was added, which alone showed less desirable. A significant correlation was observed between the overall acceptability of the cakes and their flavor. In addition, the sensory evaluation of color was found strongly correlated to darker cakes and saturated browns. The free-choice profiling was applied to the three optimized formulations along with two control formulations. The data acquired was evaluated with common components and specific weights analysis. The results, presented as similarity map and subject space, made directly observable the effects of wheat substitution by yacon and maca over the sensory characteristics of the produced cakes. The correlation of the common components with the consumers’ attributes was used for sensory description of samples. Thus, a greater proportion of maca enhances the brown color, but also the burnt aroma and taste of the cakes. Whereas, a higher proportion of yacon produces a better appearance, softness, sweetness and increased chocolate flavor. This corroborates the claim that the replacement of wheat by yacon in the produced cakes brings improvements to their sensory characteristics, while adding maca is clearly deleterious to them.
62

Desenvolvimento de drageado de soja [Glycine max (L.)] com cobertura crocante e salgada / Development soy drageado [Glycine max (l.)] with coverage and crispy salt

Schena, Deivid Padilha 06 September 2016 (has links)
O consumo de produtos derivados de soja tem aumentado no Brasil levando à busca por melhoria em características sensoriais e diversidade de produtos. A soja é considerada um alimento funcional, pois contém isoflavonas, composto que auxilia na diminuição do risco de algumas doenças, principalmente ligadas ao câncer e doenças cardiovasculares, responsáveis pela maioria de mortes no mundo. A população tem pouca aceitação a produtos considerados funcionais, principalmente quando sensorialmente não é agradável. Com isso, o objetivo desse trabalho foi desenvolver um drageado de soja com cobertura crocante e salgada. Nos testes preliminares, definiu-se três formulações, formulação 1, com adição de 5 % de farinha de aveia, formulação 2 com 15 % de farinha de aveia e formulação 3 com 25 % de farinha de aveia. Os drageados foram avaliados quanto à composição proximal, análises microbiológicas, aceitação sensorial e de textura. Nas três formulações, não houve diferença significativa na composição proximal, indicando valores menores para lipídios, quando comparado a produtos comerciais. Para fibras alimentares, o produto desenvolvido obteve valores altos quando comparado a produtos à base de soja e principalmente a soja em grãos, com destaque para as formulações 2 e 3. O resultado para fibras alimentares apresentou valores acima do esperado, onde na legislação brasileira o produto para ser considerado com alto teor de fibras e alegação funcional necessita conter no mínimo 6 %, onde na formulação 3 obteve o valor de 14,5 %, sendo o teor de fibras insolúveis mais expressivo. Os resultados das análises microbiológicas comprovaram que o produto desenvolvido se enquadra na legislação brasileira, sendo assim não oferece risco à saúde do consumidor. As análises sensoriais dos drageados indicaram que o produto teve boa aceitação em cor e textura, obtendo notas de “gostei muito” a “moderadamente” e para sabor e aceitação global de “gostei” a “gostei moderadamente”. No índice de aceitabilidade, indicaram média acima de 70 %, principalmente na formulação 2, onde obteve o maior índice na média, 74,5 %. A análise de textura instrumental dos drageados não apresentou diferença entre as formulações avaliadas e pelos valores obtidos o produto desenvolvido apresentou menor dureza quando comparado ao produto comercial, o amendoim do tipo japonês. / O Consumption of soy products has increased in Brazil, leading to improvements in sensorial characteristics and product diversity. Soy is a food for animals, a product for human consumption, a product for health and a health system. The population has little acceptance of functional products, especially when sensory is not pleasant. With this, the objective of the work was elaborated based on coverage with food and salt coverage. In the preliminary tests, three formulations, formulation 1, with addition of 5% oat flour, formulation 2 with 15% oat flour and formulation 3 with 25% oat flour were defined. The dragees were on proximal composition, microbiological analyzes, sensory and texture acceptance. In the three formulations, there was no significant difference in the proximal composition, indicating lower lipid values when compared to commercial products. For the dietary fiber, the developed product obtained high values when compared to products based on soybeans and mainly soybeans in grains, with emphasis on formulations 2 and 3. The result for the dietary fibers had values higher than expected, where in Brazilian legislation Product to be assisted with high fiber content and functional claim needs to contain at least 6%, where formulation 3 obtained the value of 14.5%, and the content of insoluble fibers more expressive. The results of the microbiological analyzes proved that the product was developed and framed in the Brazilian legislation. As sensory analysis of the dragees indicate that the product had good acceptance in color and texture, obtaining notes of "I liked" a "moderately" and for overall taste and acceptance of "liked" a "moderately liked". In the index of acceptability, they indicated a mean above 70%, mainly in formulation 2, where it obtained the highest index in the average, 74.5%. The instrumental texture analysis of the dragees showed no differences between the formulations evaluated and the values obtained in the product developed during the comparison period when the product is marketed or japanese type peanuts.
63

Effects of Acacia karroo supplementation on the quality of meat from Xhosa lopeared goats

Ngambu, Simthembile January 2011 (has links)
Effects of Acacia karroo supplementation on meat quality of Xhosa Lop-Eared goats The objective of the study was to determine the effects of A. karroo supplementation on the quality of meat from Xhosa lop-eared goats. Eighteen castrated 4-month-old Xhosa lop-eared male kids were kept at the University of Fort Hare Farm until slaughter. At the beginning of the experiment the goats had a mean body weight of 13.5 ± 0.31 kg (mean ± S.E.) and a mean body condition score (BCS) of 3.3 ± 0.16 (mean ± S.E.). From birth until weaning the kids were kept on natural pastures with their mothers. After weaning the goats were housed in an open sided barn for a period of 60 days, and were fed 500 g/head/day of Medicago sativa hay covering their maintenance and growth needs. For the purpose of the experiment, the goats were randomly divided into two balanced treatment groups of nine goats each, supplemented group (AK) and non-supplemented group (NS). The supplemented group received an additional 200g per head per day of fresh A. karroo leaves collected each day for two months. Supplementary feed was given to the goats individually in feeding troughs. The kids were slaughtered at 60 days old and samples for meat quality assessment were taken from the Longistimus dorsi muscle. The effect of A. karroo supplementation on meat quality measurements such as ultimate pH, colour and cooking losses of meat from indigenous Xhosa lop-eared goats were determined. The effect of A. karroo supplementation on the consumer sensory characteristic scores of the meat from the indigenous Xhosa lop-eared breed was also determined. There was a significant effect of the A. karroo supplementation on the meat quality measurements except for L* and a* colour coordinates. Meat from the A. karroo supplemented goats had lower pH and cooking loss scores than that of the non-supplemented goats. Acacia karroo supplementation improves meat tenderness and juiciness. There were no significant effects of A. karroo supplementation on the flavour and off- iv flavours of the meat from the supplemented goats. However, thermal preparation and consumer background had a significant effect on the meat sensory characteristics. The cooked meat had significantly higher sensory scores than the roasted meat. Female consumers reported higher sensory scores than male consumers. Consumers of different tribes and ages also reported significantly different sensory scores of meat from indigenous Xhosa lop-eared goats. Therefore, this study indicated that A. karroo supplementation can be fed to the Xhosa lop-eared goats to improve their meat quality.
64

ENHANCING AIR-WATER INTERFACE STABILITY WITH HEAT-TREATED WHEY PROTEIN IOSLATE (WPI)/HIGH ACYL GELLAN GUM (HAGG) COMPLEX PARTICLES

Rui Zhu (16637310) 08 August 2023 (has links)
<p>  </p> <p>  In this study, whey protein isolate (WPI) and high gellan gum (HAGG) were selected as natural ingredients to produce food-grade biopolymer particles for stabilizing the air-water interface. To achieve this, different mixing ratios of WPI and HAGG were employed, and heat treatment was implemented at different pH levels under the same concentration based on investigations of the pH-driven phase behavior of the WPI/HAGG complex system. The resulting WPI/HAGG complex particles were then evaluated for their ability to stabilize air-water interfaces by measuring their foaming properties.</p> <p><br></p> <p>  Foams generated using 0.1% (wt/wt) WPI/HAGG complex particles, heated at pH 5 with the mixing ratio 2:1 has demonstrated enhanced stability over a period of 30 hours compared to the WPI alone. The unique properties of these complex particles, including their smaller size (around 500nm), greater negative charge (more negative than -30 mV), and compact spherical core-shell structure, along with the higher viscosity in the continuous phase as well as the presence of small protein particles and gellan chains at the interface, collectively contribute to their superior performance as foam stabilizers. This allows for the creation of aerated food products with desirable characteristics, including product handling, enhanced texture, and prolonged shelf life in food industry.</p>
65

Appetite Measurement and Inter-individual Variability

Eunjin Cheon (14221304) 06 December 2022 (has links)
<p>  </p> <p>Appetitive sensations are widely viewed as important signals for eating decisions. Intra- and inter-individual variability have been reported in short-term studies, but it is still unknown whether individual differences are consistent over time and, whether individuals at the appetite extremes vary in energy intake. Therefore, a seventeen-week observational study was conducted to examine the stability of appetitive sensations (hunger, fullness, and thirst), implications of individual differences in appetite on energy intake and eating patterns, as well as associations between appetitive sensations and selected individual characteristics (age, gender, BMI). </p> <p>Ninety-seven (90 completers) healthy adults recorded the intensity of their hunger, fullness, and thirst hourly during all waking hours and reported their energy intake  for three days at weeks 1, 9 and 17. There were marked and stable inter-individual differences for each sensation over the 17 weeks: hunger (ANOVA, p<0.001, correlation coefficients of ratings between weeks: week 1 vs week 9, r=0.72 (p<0.001), week 1 vs week 17, r=0.67 (p<0.001), week 9 vs week 17, r=0.77 (p<0.001)), fullness (ANOVA, p<0.001, correlation coefficients of ratings between weeks: week 1 vs week 9 r=0.74 (p<0.001), week 1 vs week 17, r=0.71 (p<0.001), week 9 vs week 17, r=0.81 (p<0.001)), and thirst (ANOVA, p<0.001, correlation coefficients of ratings between weeks: week 1 vs week 9 r=0.82 (p<0.001), week 1 vs week 17, r=0.81 (p<0.001), week 9 vs week 17, r=0.88 (p<0.001)). Cross-correlation functions revealed energy intake and eating pattern exerted stronger effects on appetitive sensations than the reverse. However, the absolute effect sizes of the directional effects were small. No robust effects of the studied individual characteristics (gender, age, BMI) were observed. The primary finding is that acute and chronic sensations of hunger, fullness and thirst are stable across individuals, but are poor predictors of energy intake. </p> <p>This dissertation focuses on the study above, but as part of the training experience, two additional studies were conducted. One entailed appetite concept training to improve the validity of appetite measurements. A potential barrier to accurate appetite measurement is low conceptual understanding by study participants and resulting poor sensitivity and accuracy of responses. While each appetitive sensation is independent and has a unique definition, reported similar patterns between appetitive sensations in multiple studies raise questions about whether participants fully comprehend appetite concepts and provide accurate responses. To overcome this potential limitation, appetite concept materials were developed, and two groups of individuals were provided training either with these materials or unrelated sensory information followed by measurement of appetite responses to five different pre-loads. This study terminated early due to the COVID-19 pandemic and thus we cannot draw a conclusion for now due to the limited number of participants.  </p> <p>A second study sought to gain insights on the sensory qualities of fatty acids as part of an effort to determine if oral fat detection is based, in part, on gustatory cues. It has been argued that if fat taste is a primary, the sensations imparted by fats should yield unique percepts and these may be determined by fatty acid chain length. In particular, because acids impart a sour taste, free fatty acids may simply be detected as sour. The fat taste study entailed measurement of intensity ratings with or without sour adaptation (to assess sour notes), tongue locations of taste detection, and subjective descriptors of fatty acids. This study examined intensity and quality ratings of NEFA's ranging from C2 to C18. Oral sites and the time course of sensations were also monitored. Given all NEFA contain carboxylic acid moieties capable of donating hydrogen ions, the primary stimulus for sour taste, testing was conducted with and without sour adaptation to explore the contribution of sour taste across the range of NEFA. Short chain NEFA (C2-C6) were rated as predominantly sour, and this was diminished in C2 and C4 by sour adaptation. Medium chain NEFA (C8-C12) were rated as mainly irritating with long chain NEFA (C18) described mostly as bitter. The latter may reflect the lack of “fatty” lexicon to describe the sensation. Short chain NEFA were mostly localized to the anterior tongue and were of rapid onset. The sensation from medium chain NEFA was attributed to the lateral tongue while medium and long chain NEFA sensations were predominantly localized to the back of the tongue and throat and had a longer lag time. The findings indicate there is a systematic transition of NEFA taste quality and irritation with increments in chain length and this is consistent with multiple modes of transduction.</p>
66

BIOINFORMATIC MODELLING AND FUNCTIONALIZATION OF PEA PROTEIN THROUGH COLD DENATURATION WITH APPLICATIONS IN EXTRUSION, GELATION, AND EMULSIFICATION

Harrison Dale Brent Helmick (17467545) 29 November 2023 (has links)
<p dir="ltr">The impacts of processing on protein structure are of broad interest to the food science community including ingredient producers, product developers, and researchers. Processing and isolation steps induce protein structural changes which occur due to temperature based, shear, and chemical inputs, leading to denatured protein with different functionalities. However, exploration of the protein folding landscape as a way to intentionally modify protein conformation is not widely understood in food science. This particularly applies to cold denaturation, which is the structural changes in protein as the result of low temperature treatments.</p><p dir="ltr">This work has two primary goals. The first was to develop understanding of protein conformations resulting from cold denaturation and its implications for food textural properties. Pea protein was selected for this work since it is a source of plant-based protein that has recently grown in popularity and contains many hydrophobic amino acids that would make is susceptible to cold denaturation. Cold denaturation was studied using physicochemical techniques including differential scanning calorimetry, Fourier transform infrared spectroscopy, zeta potential, fluorescence spectroscopy, dynamic light scattering, and rheology. These techniques are used to characterize untreated pea protein, and proteins that have been modified using different combinations of ethanol, shear forces, acidic conditions, extrusion, and temperatures below 0°C. Significant physicochemical differences are found as the result of low temperatures, driven by an increase in surface hydrophobicity and electrostatic interactions. These differences led to protein gelation through hydrophobic forces, changing the nature of gels. Similarly, the increase in protein hydrophobicity leads to more stable emulsions from these products and unique fatty extrudates.</p><p dir="ltr">A second aim of this work developed bioinformatic models to interpret physiochemical data and provide mechanistic understanding of the process, as well as predict functional properties based on protein models. Strong correlations are found for the zeta potential, secondary structure, hydrogen bonds, and surface hydrophobicity. These models are used to convert data into physicochemical energy and used to provide reasonable estimates of mechanical properties of pea protein in extrusion, gelation, and emulsification. Together, this work shows that cold denaturation may be a useful tool for food product developers creating fatty and creamy textures. It also suggests bioinformatic modeling as a tool to estimate protein functionality, which could lead to tremendous time savings in process and product design.</p>
67

An assessment of the quality and acceptance of a ready-to-use supplement, Sibusiso, by human immunodeficiency virus and human immunodeficiency virus/tuberculosis treated patients in KwaZulu-Natal.

Mabaso, Prudence Bongekile. 29 November 2013 (has links)
Introduction: Malnutrition is a health issue directly and indirectly contributing towards high rates of morbidity and mortality globally, particularly in developing countries. South Africa (SA) is faced with a double burden of diseases with a high prevalence of both under and over nutrition. The high prevalence of Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) in SA worsens undernutrition. HIV/AIDS increases nutrient requirements and inadequate food intake results in malnutrition. Nutrition support through food supplementation is important to combat the high prevalence of malnutrition in sub-Saharan African countries including South Africa. Thus, a groundnut-soya based supplementary paste, Sibusiso, has been produced. However, its nutritional composition and acceptability have not been studied. Objectives: (i) To determine the nutritional composition and physical properties of a ready-to-use supplement, Sibusiso, (ii) To determine the sensory acceptability of Sibusiso among healthy subjects; and sensory acceptability and perceptions of Sibusiso by subjects treated for HIV and HIV/TB. Materials and methods: The nutritional composition, colour and texture of Sibusiso and a commercial peanut butter (control) were analysed following standard procedures. A cross-sectional consumer acceptability test was done using a 5-point facial hedonic scale (healthy control group, n = 68; HIV, n = 88 and HIV-TB co-infection treated, n = 51). A total of six focus group discussion sessions (HIV subjects = 4 sessions and HIV/TB co-infected subjects = 2 sessions) were also conducted. Results and discussions: The protein content of Sibusiso (16 g/100 g) was almost half that of the commercial peanut butter (control), (25 g/100 g). However, Sibusiso contained 1.4 times more ash (4 g/100 g) and almost twice as much carbohydrate (40 g/100 g) compared to the commercial peanut butter (22 g/100 g). The fat (40 g/100 g) and energy (2 624 kJ/ 100 g) content of Sibusiso was not substantially different from that of the commercial peanut butter which was 43 g/100 g and 2 852 kJ/100 g, respectively. The lysine content of Sibusiso (58 mg/g) was about 1.7 times higher than that of the commercial peanut butter. The methionine (11 mg/g) and histidine (35 mg/g) content of Sibusiso was almost twice that of the commercial peanut butter, respectively. The nutrient content of Sibusiso was either similar or slightly more than that of other ready-to-use supplements such as Plumpy’nut®. Sibusiso met the FAO/WHO/UNU recommendations for essential amino acids. The consumption of 50 g of Sibusiso per day may provide approximately 35% of the Estimated Energy Requirements (EER) and 30% of the Recommended Dietary Allowance (RDA) for protein for adults. Sibusiso was brown in colour, similar to the commercial peanut butter. Its textural attributes were found similar to that of the commercial peanut butter but harder and stickier. The acceptability of Sibusiso was significantly associated (p ≤ 0.05) with the health status of consumers. Overall, Sibusiso was liked by 94% of HIV and HIV/TB individuals (mean score: 4) compared to 85% for the healthy group (control). More than 90% of the HIV/TB and HIV treated individuals liked the taste compared to the control group (86%, mean score: 4). The colour and mouthful were rated 'good' by more than 80% of the HIV and HIV/TB group, mean score: 3, with only 68% among the healthy group, mean score: 4.1. Conclusion: Sibusiso is a good source of nutrients and was found to be acceptable to HIV and HIV/TB treated consumers. It may be effective in alleviating disease-related malnutrition among vulnerable individuals such as those infected by HIV and HIV/TB. / Thesis (M.Sc.Hum.Nut.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
68

A study of the quality and feasibility of Sibusiso, a ready-to-use food.

Mahlangu, Zodwa Nita. January 2012 (has links)
A ready-to-use food (RUF), Sibusiso, has the potential to alleviate protein- energy malnutrition. However, its nutritional composition, physical properties, consumer acceptability, and economic feasibility for use are unknown. This study aimed to determine the nutritional composition and physical properties of a RUF, Sibusiso. As well as to assess the consumer acceptability of Sibusiso to healthy and HIV infected children on antiretroviral (ARV) medication, and the caregiver‟s attitudes towards Sibusiso. The feasibility of using Sibusiso for nutrition rehabilitation was also determined. Methodology: Four samples of Sibusiso and a peanut butter (control) were analysed for their nutritional composition and physical properties. The consumer acceptability of Sibusiso to healthy children and HIV infected children on ARVs (ART group) was determined using a five-point facial hedonic rating scale. Focus group discussions were conducted to assess the attitudes and perceptions of caregivers surrounding Sibusiso. These caregivers had children who were either malnourished or at risk of malnutrition. The financial feasibility of using Sibusiso for nutrition rehabilitation was determined using published data. The results revealed that Sibusiso was a good source of energy (2624 kJ/100 g) and quality protein (15.7 g/100 g). The nutritional composition of Sibusiso met the WHO/WFP/SCN/UNICEF recommendations for RUF. Instrumental colour analysis indicated that both Sibusiso and the peanut butter had a brown colour, although Sibusiso was slightly lighter. Sibusiso had the same spreadability or hardness as the peanut butter, but it was stickier than the peanut butter. Based on the sensory evaluation, Sibusiso was found acceptable to both healthy (n=121) and HIV infected children (n=51). Over 65% of the children in both the healthy and ART group liked the taste, smell and mouthfeel of Sibusiso. The caregivers also found Sibusiso acceptable and were willing to buy it, but at half its current price (60 ZAR/ 500 g). The price of Sibusiso and perception of the caregivers that Sibusiso was a peanut butter were the main factors that affected their willingness to buy the product. Financial feasibility analysis showed that the estimated cost (5.99 ZAR/day) of rehabilitating a child using Sibusiso was higher than the KwaZulu-Natal Department of Health nutrition budget of 0.02 ZAR/day. Sibusiso is a good source of energy and quality protein, and it is fairly acceptable to children with HIV and caregivers. This indicates that Sibusiso has a potential to alleviate protein-energy malnutrition in the targeted groups. Yet, Sibusiso is expensive. There would be a need to somehow reduce the cost of Sibusiso so that it would be financially feasible to use it in nutrition intervention programmes. / Thesis (M.Sc.Hum.Nut.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
69

Elaboração da farinha de palma aditivada com sabor camarão para alimentação humana. / Elaboration of the additive palm meal flavored shrimp for human consumption.

OLIVEIRA, José Marcos Freitas de. 01 July 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-01T13:46:52Z No. of bitstreams: 1 JOSÉ MARCOS FREITAS DE OLIVEIRA - DISSERTAÇÃO PPGEA 2011..pdf: 8394725 bytes, checksum: c724d80a99ec4cb907ef7c29ea570318 (MD5) / Made available in DSpace on 2018-07-01T13:46:52Z (GMT). No. of bitstreams: 1 JOSÉ MARCOS FREITAS DE OLIVEIRA - DISSERTAÇÃO PPGEA 2011..pdf: 8394725 bytes, checksum: c724d80a99ec4cb907ef7c29ea570318 (MD5) Previous issue date: 2011-09 / CNPq / O objetivo desta pesquisa foi estudar o processo de secagem das farinhas de palma gigante e da farinha da cabeça de camarão para alimentação humana. Foram utilizados cladódios de palma gigante e cabeça de camarão, distribuídos em um delineamento inteiramente casualizado com um arranjo 2x6; (2 farinhas: farinha de palma e farinha com diferentes teores de camarão) e (6 tratamentos de secagem: in natura, 60°C, 70°C, 80°C, 90°C e 100°C) com 3 repetições. Foram analisados teor de água, cinzas, protídeos, lipídios, carboidratos, valor calórico total (VCT), pH, açúcares totais e redutores, sólidos solúveis totais. Na análise sensorial com população de 80 provadores, foram avaliados aparência, cor e odor da farinha de palma com 15, 20 e 25% de farinha de camarão, utilizando-se uma escala hedônica de 1 a 7 pontos. Os resultados de secagem foram analisados com a utilização do programa Statistica 7 e a comparação entre os parâmetros fisioquímicos foi utilizado o programa Assistat versão 7.5. Conclui- se que: Dentre os três modelos aplicados no ajuste das curvas de secagem aos dados experimentais de secagem da palma e da cabeça de camarão, o que melhor representa osdados experimentais de secagem é o de Page, em todas as temperaturas; Os produtos elaborados com maiores percentuais de farinha de cabeça de camarão, 20 e 25 %, foram os preferidos pelos provadores, quanto aos parâmetros Aparência e cor, com médias entre 6 e 7, correspondendo a um conceito entre gostei ligeiramente e gostei regularmente. / The objective of this research was to study the drying process of flour and palm giant head flour shrimp for human consumption. Cladodes of giant palm and shrimp head were used, distributed in a completely randomized design with a 2x6 arrangement, (2 flour: palm flour and palm flour with different leveis of shrimp) and (6 drying treatments: fresh, 60 °C, 70 °C, 80 °C, 90 °C and 100 °C) with 3 replications. We analyzed water content, ash, proteins, lipids, carbohydrates, total caloric value (TCV), pH, total and reducing sugars, soluble solids. A sensory analysis with a population of 80 tasters was performed; appearance, color and odor of palm flour with 15, 20 and 25% flour of shrimp had been evaluated, a hedonic scale of 1 to 7 points was used. The drying results were analyzed using Statistica 7 and comparing the physical chemical parameters we used software version 7.5 Assistat. It was concluded that: Among the three models used in adjusting the drying curve to experimental data and drying palm head shrimps, which best represents the experimental data of drying is to Page, at ali temperatures; Products manufactured with the highest percentages of shrimp head meai, 20 and 25%, were preferred by tasters, with averages between 6 and 7, corresponding to a concept between enjoyed slightly and enjoyed regularly.
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Estimativa da vida útil de hambúrguer de Carpa capim por meio de análise de sobrevivência, cut-off point e espectroscopia de infravermelho próximo / Shelf life estimation of grass carp hamburger through survival analysis, cut-off point and near-infrared spectroscopy

Marques, Caroline 07 December 2016 (has links)
CAPES; CNPq / O consumo de pescado no Brasil está abaixo da média mundial e isso se deve a fatores econômicos, culturais e também à baixa disponibilidade desse alimento. Para estimular o consumo, devido ao alto valor nutricional desse tipo de carne, uma das estratégias é transformar o pescado em um produto prático, como o hambúrguer. Entretanto, em decorrência do pH próximo a neutralidade e da alta atividade de água, o pescado e seus derivados possuem uma vida útil limitada, dependendo das condições de armazenamento. Um dos parâmetros mais questionáveis da estabilidade desse produto é a oxidação lipídica, reação que ocorre até mesmo em baixas temperaturas. Sabe-se que a qualidade sensorial de um produto é fundamental para o consumidor na hora da compra e do consumo. Uma vez que o acompanhamento sensorial da vida útil leva tempo e considerável investimento, a Espectroscopia de Infravermelho Próximo (NIR) entra como técnica instrumental rápida, não destrutiva e recente, para o mesmo fim, a qual consegue analisar vários parâmetros da amostra ao mesmo tempo. Nesse sentido, o objetivo deste trabalho foi estimar a vida útil de hambúrgueres de Carpa capim por meio de análise de sobrevivência e cut-off point, além da utilização do NIR para construção de modelos de predição de vida útil pelo método dos mínimos quadrados parciais (PLS).O hambúrguer foi elaborado com filés de Carpa capim moídos e lavados (lavagem básica), embalados a vácuo e armazenados sob refrigeração durante 30 dias. Uma equipe sensorial foi selecionada e treinada para avaliar o ranço nas amostras de hambúrguer por meio de análise discriminativa triangular, análise estatística de variância (ANOVA), gráfico de valor F e box plots. A avaliação físico-química da matéria-prima mostrou adequação com a legislação vigente para frescor (pH e bases voláteis totais N-BVT); apresentou baixo teor de lipídios e alto conteúdo proteico. A caracterização do produto verificou que o hambúrguer de Carpa capim está de acordo com a legislação quanto ao teor de lipídios e proteína, com valor semelhante ao dos filés para o valor calórico. As análises de referência para o NIR apontaram que o Índice de iodo e a atividade de água (Aw) não foram capazes de diferenciar os hambúrgueres durante o armazenamento; já as Substâncias Reativas do Ácido Tiobarbitúrico (TBARS) e o pH apresentaram resultados que corroboram as mudanças ocorridas na matriz hambúrguer. A rancidez foi observada pela equipe sensorial treinada e também verificada pela análise de TBARS, as quais tiveram crescimento exponencial, com coeficientes de correlação superiores a 0,95. Modelos robustos por meio do PLS foram obtidos com o NIR para os parâmetros ranço, TBARS e pH, resultado que não se repetiu para o Índice de iodo, Aw e cor. A análise de sobrevivência determinou o final da vida útil do hambúrguer de Carpa Capim em 17 dias, já para o cut-off point apontou 15 dias. Ambas as metodologias mostraram-se eficientes para estimativa da vida útil do produto analisado, ao contrário do NIR que subestimou a data da vida útil, gerando diferenças de 56 a 76% e não se mostrou eficiente para a estimativa considerando os valores preditos pelo modelo gerado para o defeito ranço. / The fish consumption in Brazil is below the world average and this is due to economic, cultural factors and also to the low availability of this food. To stimulate consumption, due to the high nutritional value of this type of meat, one of the strategies is to turn the fish into a convenient product, such as hamburger. However, due to the pH close to neutrality and the high water activity, fish and fish products have a limited shelf life, depending on storage conditions. One of the questionable parameters about the stability of this product is the lipid oxidation reaction, which occurs even at low temperatures. It is known that the sensory quality of a product is critical to the consumer at the moment of acquisition and consumption. Once the sensory monitoring of the shelf life takes time and considerable investment, the Near Infrared spectroscopy (NIR) comes as a fast instrumental technique, nondestructive and recent, with the same purpose, which can access multiple parameters from the sample at the same time. Thus, the objective of this study was to estimate the shelf life of grass carp burgers through survival analysis and cut-off point, in addition to the use of NIR to build shelf life prediction models by the Partial Least Squares (PLS) method. The burger was made with grass carp fillets ground and washed (basic washing), vacuum packed and stored under refrigeration for 30 days. A sensory panel was selected and trained to evaluate rancidity in hamburger samples by means of triangular discriminative analysis, variance statistical analysis (ANOVA), F value chart and box plots. The physical-chemical evaluation of raw materials showed adequacy with current legislation for freshness (pH and total volatile bases TVB-N); presented low lipid content and high protein content. The characterization of the product verified that the burger complies with the legislation on the lipid and protein content, with a caloric value similar to the fillets. The reference analyzes for NIR pointed out that the iodine index and water activity (Aw) were not able to differentiate the burgers during storage; the Thiobarbituric Acid Reactive Substances (TBARS) and the pH presented results corroborating the changes in the burger matrix. The rancidity was observed by the trained sensory panel and also verified by TBARS analysis, where both had exponential growth, with correlation coefficients greater than 0.95. Robust models were obtained through PLS using the NIR to rancidity, TBARS and pH parameters, a result not repeated for iodine index, Aw and color. Survival analysis determined the end of shelf life of grass carp grass burger in 17 days and the cut-off point in 15 days. Both methods were effective to estimate the shelf life of the product, unlike the NIR that underestimated the end date, generating differences ranging from 56 to 76%, not efficient for this estimative, considering the values predicted by the model generated for the defect rancidity.

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