Both the theory of sequential analysis developed by Wald and that developed by Rao may be applied to binomial distributions and may be used to select judges for taste testing experiments. The duo-trio or triangle test may both be used as the fundamental test in either sequential process. Wald has applied his sequential analysis to binomial distributions and it was only necessary to associate duo trio and triangle trials with his examples on industrial sampling inspection. This was done by associating incorrect tasting decisions with defectives in industrial sampling. It has been noted Ghat choice of α and β, the risks of type I and type II errors, may depend on the availability of potential judges and on the time and material available to the experimenter. / Master of Science

This study set out to establish artificial neural networks (ANN) as an alternate to regression methods (multiple linear, principal components and partial least squares regression) to predict consumer liking from trained sensory panel data. The study has two parts viz., I) Flavour study - evaluation of ANNs to predict consumer flavour preferences from trained sensory panel data and 2) Fragrance study ??? evaluation of different ANN architectures to predict consumer fragrance liking from trained sensory panel data. In this study, a multi-layer feedforward neural network architecture with input, hidden and output layer(s) was designed. The back-propagation algorithm was utilised in training of neural networks. The network learning parameters such as learning rate and momentum rate were optimised by the grid experiments for a fixed number of learning cycles. In flavour study, ANNs were trained using the trained sensory panel raw data as well as transformed data. The networks trained with sensory panel raw data achieved 98% correct learning, whereas the testing was within the range of 28 -35%. A suitable transformation methods were applied to reduce the variations in trained sensory panel raw data. The networks trained with transformed sensory panel data achieved between 80-90% correct learning and 80-95% correct testing. In fragrance study, ANNs were trained using the trained sensory panel raw data as well as principal component data. The networks trained with sensory panel raw data achieved 100% correct learning, and testing was in a range of 70-94%. Principal component analysis was applied to reduce redundancy in the trained sensory panel data. The networks trained with principal component data achieved about 100% correct learning and 90% correct testing. It was shown that due to its excellent noise tolerance property and ability to predict more than one type of consumer liking using a single model, the ANN approach promises to be an effective modelling tool.

Call number: LD2668 .T4 1984 J32 / Master of Science

Call number: LD2668 .T4 1985 L96 / Master of Science

Assignment (MComm)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: This study is the result of part-time work done at a product development centre. The organisation extensively makes use of trained panels in sensory trials designed to asses the quality of its product. Although standard statistical procedures are used for analysing the results arising from these trials, circumstances necessitate deviations from the prescribed protocols. Therefore the validity of conclusions drawn as a result of these testing procedures might be questionable. This assignment deals with these questions. Sensory trials are vital in the development of new products, control of quality levels and the exploration of improvement in current products. Standard test procedures used to explore such questions exist but are in practice often implemented by investigators who have little or no statistical background. Thus test methods are implemented as black boxes and procedures are used blindly without checking all the appropriate assumptions and other statistical requirements. The specific product under consideration often warrants certain modifications to the standard methodology. These changes may have some unknown effect on the obtained results and therefore should be scrutinized to ensure that the results remain valid. The aim of this study is to investigate the distribution and other characteristics of sensory data, comparing the hypothesised, observed and bootstrap distributions. Furthermore, the standard testing methods used to analyse sensory data sets will be evaluated. After comparing these methods, alternative testing methods may be introduced and then tested using newly generated data sets. Graphical displays are also useful to get an overall impression of the data under consideration. Biplots are especially useful in the investigation of multivariate sensory data. The underlying relationships among attributes and their combined effect on the panellists’ decisions can be visually investigated by constructing a biplot. Results obtained by implementing biplot methods are compared to those of sensory tests, i.e. whether a significant difference between objects will correspond to large distances between the points representing objects in the display. In conclusion some recommendations are made as to how the organisation under consideration should implement sensory procedures in future trials. However, these proposals are preliminary and further research is necessary before final adoption. Some issues for further investigation are suggested. / AFRIKAANSE OPSOMMING: Hierdie studie spruit uit deeltydse werk by ’n produk-ontwikkeling-sentrum. Die organisasie maak in al hul sensoriese proewe rakende die kwaliteit van hul produkte op groot skaal gebruik van opgeleide panele. Alhoewel standaard prosedures ingespan word om die resultate te analiseer, noodsaak sekere omstandighede dat die voorgeskrewe protokol in ’n aangepaste vorm geïmplementeer word. Dié aanpassings mag meebring dat gevolgtrekkings gebaseer op resultate ongeldig is. Hierdie werkstuk ondersoek bogenoemde probleem. Sensoriese proewe is noodsaaklik in kwaliteitbeheer, die verbetering van bestaande produkte, asook die ontwikkeling van nuwe produkte. Daar bestaan standaard toets- prosedures om vraagstukke te verken, maar dié word dikwels toegepas deur navorsers met min of geen statistiese kennis. Dit lei daartoe dat toetsprosedures blindelings geïmplementeer en resultate geïnterpreteer word sonder om die nodige aannames en ander statistiese vereistes na te gaan. Alhoewel ’n spesifieke produk die wysiging van die standaard metode kan regverdig, kan hierdie veranderinge ’n groot invloed op die resultate hê. Dus moet die geldigheid van die resultate noukeurig ondersoek word. Die doel van hierdie studie is om die verdeling sowel as ander eienskappe van sensoriese data te bestudeer, deur die verdeling onder die nulhipotese sowel as die waargenome- en skoenlusverdelings te beskou. Verder geniet die standaard toetsprosedure, tans in gebruik om sensoriese data te analiseer, ook aandag. Na afloop hiervan word alternatiewe toetsprosedures voorgestel en dié geëvalueer op nuut gegenereerde datastelle. Grafiese voorstellings is ook nuttig om ’n geheelbeeld te kry van die data onder bespreking. Bistippings is veral handig om meerdimensionele sensoriese data te bestudeer. Die onderliggende verband tussen die kenmerke van ’n produk sowel as hul gekombineerde effek op ’n paneel se besluit, kan hierdeur visueel ondersoek word. Resultate verkry in die voorstellings word vergelyk met dié van sensoriese toetsprosedures om vas te stel of statisties betekenisvolle verskille in ’n produk korrespondeer met groot afstande tussen die relevante punte in die bistippingsvoorstelling. Ten slotte word sekere aanbevelings rakende die implementering van sensoriese proewe in die toekoms aan die betrokke organisasie gemaak. Hierdie aanbevelings word gemaak op grond van die voorafgaande ondersoeke, maar verdere navorsing is nodig voor die finale aanvaarding daarvan. Waar moontlik, word voorstelle vir verdere ondersoeke gedoen.

Call number: LD2668 .T4 1986 R53 / Master of Science / Hospitality Management and Dietetics

The objective of this research was to determine the acceptability and preference of peanut butter and three different flavors of soynut butter among humans. Six hundred and sixty-two volunteers (401 females, 258 males and 3 unknown) between the ages of 18 and up were randomly asked to fill out a demographic survey and taste 1 tsp. (5.33 g) of three different soynut butters (creamy, creamy with honey, and creamy with chocolate) and 1 tsp. (5.33 g) of peanut butter on saltine crackers. After taste testing the soynut butters/peanut butter, volunteers were asked to rate each product on a 9-point hedonic rating scale based on appearance, texture, and flavor; the subjects were also asked as to whether they would purchase the nut butters. Demographic information such as participants' age, gender, year in school, and ethnicity were collected, along with questions concerning their frequency of exercise, eating and smoking habits, and health status of themselves and their families.The creamy with honey and creamy soynut butters were rated highest by both genders for all variables (i.e., appearance, texture, flavor, purchase). The purchase variable determined statistical significance between females and males. The females indicated by their rating that they would be more likely to purchase the chocolate soynut butter vs. the peanut butter, while the males indicated purchasing preference of peanut butter over the chocolate soynut butter.Given that both creamy with honey and creamy soynut butters were accepted by this population based on appearance, texture, and flavor, future research in this area should focus on soy foods in humans and biochemical parameters, marketing niches, specific ethnic or age preferences, and education of the health benefits of soy. / Department of Family and Consumer Sciences

O objetivo do trabalho foi elaborar e caracterizar tofus, com e sem adição de orégano, produzidos com duas cultivares de soja, BRS 284 e BMX Potência RR, oriundas de Mauá da Serra – PR, safra 2011/2012. Os grãos foram avaliados quanto a sua composição proximal, fibras alimentares, isoflavonas e propriedades tecnológicas. Também foram determinados a quantidade de água absorvida na maceração dos grãos, o rendimento e a composição proximal dos extratos de soja. Os tofus foram avaliados quanto à composição proximal, isoflavonas e aceitação sensorial. As duas cultivares se destacaram pelo teor de proteínas BRS 284 (33,24%) e BMX Potência RR (34,74%), lipídios BRS 284 (22,54%) e BMX Potência RR (21,72%) e fibras alimentares totais BRS 284 (26,64%) e BMX Potência RR (27,13%), sendo a maior fração constituída de fibras insolúveis. Ambas cultivares apresentaram altos valores de isoflavonas totais BRS 284 (591,70 mg.100g-1) e BMX Potência RR (865,36 mg.100g-1), devido ao local de plantio possuir temperaturas baixas. As cultivares BRS 284 e BMX Potência RR obtiveram valores para volume de intumescimento de 4,31 mL/g e 4,12 mL/g; índice de absorção de água de 2,75 g/g e 2,75 g/g e índice de absorção de óleo de 2,87 g/g e 2,60 g/g, respectivamente. Os grãos das duas cultivares de soja apresentaram diferenças nos teores de umidade, lipídios, proteínas e isoflavonas totais. Durante a maceração os grãos das duas cultivares absorveram em média 1,2 mL mL/g de água. O rendimento dos extratos de soja foram elevados, com média de 77%. Os extratos de soja não apresentaram diferença significativa em sua composição proximal. Os tofus produzidos com as duas cultivares se destacaram pelo teor de proteínas BRS 284 Padrão e Orégano (9,21% e 8,67%) e BMX Potência RR Padrão e Orégano (11,16% e 10,90%), seguido por lipídios BRS 284 Padrão e Orégano (5,26% e 4,89%) e BMX Potência RR Padrão e Orégano (4,38% e 4,24%). Os tofus das duas cultivares apresentaram altos teores de isoflavonas totais BRS 284 Padrão e Orégano (243,57 mg.100g-1 e 219,18 mg.100g-1) e BMX Potência RR Padrão e Orégano (262,64 mg.100g-1 e 330,38 mg.100g-1). Os tofus padrão e com adição de orégano da cultivar BRS 284 não apresentaram diferença para os teores de proteínas e nos produtos elaborados com a cultivar BMX Potência RR, não houve diferença nos teores de lipídios e cinzas. Os tofus com adição de orégano apresentaram melhor aceitabilidade e também maior intenção de compra pelos julgadores, comprovando a importância do atributo sabor na aceitação do tofu por parte de não consumidores. / The aim of the study was to develop and characterize tofu, with and without the addition of oregano, produced with two soybean cultivars, BRS 284 and BMX Potência RR, from Maua da Serra – PR, harvest 2011/2012. The grains were evaluated for proximate composition, dietary fiber, isoflavones and technological properties. Were also determined the amount of water absorbed in the soaking of the grains, the yield and the proximal composition of soymilk. The tofu were evaluated for proximate composition, isoflavones and sensory acceptance. Both cultivars stood out for its protein content BRS 284 (33,24%) and BMX Potência RR (34,74%), lipids BRS 284 (22,54%) and BMX Potência RR (21,72%) and total dietary fiber BRS 284 (26,64%) and BMX Potência RR (27,13%), being the largest fraction consists of insoluble fiber. Both cultivars showed high levels of total isoflavones BRS 284 (591,70 mg.100g-1) and BMX Potência RR (865,36 mg.100g-1), due to the planting site possess low temperatures. The cultivars BRS 284 and BMX Potência RR obtained values for volume swelling of 4,31 mL/g and 4,12 mL/g; water absorption index of 2,75 g/g e 2,75 g/g and oil absorption index of 2,87 g/g and 2,60 g/g, respectively. The grains of two soybean cultivars showed differences in moisture, lipids, proteins and total isoflavones. During maceration, grains of both cultivars absorbed on average 1,2 mL mL/g of water. The yield of soymilk were high, with an average of 77%. The soy extract showed no significant difference between their composition. The tofu produced in both cultivars stood out for its high protein content Standard BRS 284 and Oregano (9,21% e 8,67%) and Standard BMX Potência RR and Oregano (11,16% e 10,90%), followed by lipids content Standard BRS 284 and Oregano (5,26% e 4,89%) and Standard BMX Potência RR and Oregano (4,38% e 4,24%). The tofus of both cultivars showed high levels of total isoflavones Standard BRS 284 and Oregano (243,57 mg.100g-1 e 219,18 mg.100g-1) and Standard BMX Potência RR and Oregano (262,64 mg.100g-1 e 330,38 mg.100g-1). The standard tofu and adding oregano from cultivar BRS 284 showed no difference in the protein content, and products made with cultivar BMX Potência RR, there was no difference in the levels of lipids and ash. The tofu with oregano showed better acceptability and also better purchase intent by the judges, what indicates the importance of flavor attribute in acceptance by non-consumers.

A jabuticaba é fruto tropical com propriedades nutricionais importantes, sendo excelente fonte de carboidratos, fibras, compostos fenólicos e minerais como ferro, cálcio e fósforo. Esse fruto e suas frações podem ter extensa aplicabilidade tanto para a indústria, como para a comercialização e consumo in natura. Pesquisas apontam que a maior fração de espécies biologicamente ativas da jabuticaba encontra-se na casca, podendo viabilizar seu uso para elaboração de um produto como alternativa de aproveitamento da mesma, possibilitando a produção de alimentos com propriedades funcionais. Tal iniciativa permite avançar com estudos direcionados aos compostos bioativos presentes tanto na fruta como nos produtos derivados, bem como avaliar a influência do processamento nestes compostos. Com base no exposto, o presente estudo teve como objetivo avaliar os compostos bioativos da casca de jabuticaba (Plinia cauliflora) e dos remanescentes na farinha da casca de jabuticaba para posterior aplicação em biscoito tipo cookie. A variação entre os teores destes compostos presentes na casca e na farinha da casca de jabuticaba também foram avaliados. O estudo foi realizado por meio de análises físico-químicas dos extratos hidroalcoólicos da casca e farinha deste, sendo elas, umidade, proteína, lipídeos, cinzas, fibras, carboidratos, valor calórico, acidez total titulável, pH, compostos bioativos (fenóis, flavonóides, antocianinas, taninos condensados) e atividade antioxidante por três métodos distintos (DPPH expresso em TEAC, DPPH expresso em EC50 e FRAP). A casca demonstrou ser rica em compostos fenólicos, dentre eles, antocianinas, flavonóides e taninos condensados, reforçando que a composição apresentou teores consideráveis de atividade antioxidante, tanto no sequestro como na interação com radicais livres. Também apresentou altos teores de umidade e conteúdos consideráveis de fibras e carboidratos. A farinha da casca de jabuticaba apresentou umidade condizente com a legislação e teores consideráveis de carboidratos, compostos fenólicos em geral e atividade antioxidante, além de ser fonte de fibras. Também se observou na mesma a concentração dos compostos analisados devido à desidratação das cascas e outros fatores. A partir da farinha foram elaborados biscoitos tipo cookie com substituições de 0,0, 2,5, 5,0 e 7,5% de farinha de trigo integral por farinha da casca de jabuticaba e os mesmos avaliados físico-quimicamente através das mesmas variáveis utilizadas na casca e farinha. Posteriormente foram avaliados microbiologicamente antes de serem encaminhados à análise sensorial, já aprovada pelo Comitê de Ética, onde foram realizados testes de aceitação e intenção de compra. Os cookies obtiverem teores de umidade condizentes com a legislação, além de revelarem-se fonte de proteínas e fibras. Todas as formulações apresentaram redução na concentração dos compostos bioativos devido ao processo de cocção, porém também houve manutenção de teores desejáveis de compostos fenólicos e atividade antioxidante. Os resultados sensoriais permitem concluir que todas as amostras foram aceitas, comparadas ao padrão. A formulação com 7,5% de farinha da casca de jabuticaba foi considerada ideal para adicionar em biscoitos tipo cookie, pois resultou em maiores teores de compostos fenólicos e também em maiores níveis de ação antioxidante, resultando em produto com conteúdo de propriedades biologicamente ativas elevado, sem interferir na qualidade sensorial e nos padrões de identidade do mesmo. / The jabuticaba is a tropical fruit with important nutritional properties, and excellent source of carbohydrates, fiber, phenolic compounds and minerals like iron, calcium and phosphorus. This fruit and its fractions may have extensive applicability both for industry and for the commercialization and consumption in natura. Research indicates that the greatest fraction of the jabuticaba biologically active species is in the skin, may enable their use for production of a product as an alternative use of the same, enabling the production of foods with functional properties. This allows forward with studies directed to the bioactive compounds present in both the fruit as in derivatives and to evaluate the influence of processing these compounds. Based on the above, the present study aimed to evaluate the bioactive compounds from the jabuticaba skin (Plinia cauliflora) and remaining in the jabuticaba flour skin for later use in biscuit type cookie. The variance between the levels of these compounds in the jabuticaba skin and flour skin were also evaluated. The study was conducted by means of physicochemical analysis of hydroalcoholic extracts of the skin and flour, they being, moisture, protein, lipid, ash, fiber, carbohydrates, calories, total titratable acidity, pH, bioactive compounds (phenols, flavonoids, anthocyanins, condensed tannins) and antioxidant activity by three different methods (DPPH expressed in EC50, DPPH expressed in TEAC and FRAP). The skin has proved to be rich in phenolic compounds, among them, anthocyanins, flavonoids and condensed tannins, reinforcing that the composition showed considerable levels of antioxidant activity in both the scavenging and the interaction with free radicals. Also showed high levels of moisture and considerable content of fiber and carbohydrates. The jabuticaba flour skin showed consistent moisture with legislation and considerable amounts of carbohydrates, overall phenolic compounds and antioxidant activity, besides being a source of fiber. It is also noted there in the concentration of the analyzed compounds due to dehydration of the skins and other factors. From flour, biscuits type cookie were prepared with substitutions of 0.0, 2.5, 5.0 and 7.5% whole wheat flour for jabuticaba skin flour and they assessed physicochemical form with the same variables used in the skin and flour. Subsequently were evaluated microbiologically before being forwarded to the sensory analysis, already approved by the Ethics Committee, where acceptance and purchase intent tests were performed. Cookies obtain moisture levels consistent with the law, apart from revealing the source of protein and fiber. All formulations showed reduction in the concentration of bioactive compounds due to the cooking process, but also there was maintenance of desirable levels of phenolics and antioxidant activity. Sensory results showed that all samples were accepted, compared to the standard. The formulation with 7.5 % jabuticaba skin flour was considered ideal for adding in biscuits type cookie, as showed higher content of phenolic compounds and also in higher levels of antioxidant activity, resulting in products with high content of biologically active properties without interfering with the sensory quality and standards of identity.

Neste trabalho, foram estudadas a possibilidade e os benefícios na aplicação da farinha de tempeh como substituinte parcial da farinha de soja integral. Para isto, inicialmente foram avaliados a composição proximal e os teores de isoflavonas (agliconas e totais) nas farinhas de soja integral e de tempeh. Foram utilizados grãos de soja das cultivares BRS 216, BRS 257 e BRS 267, a fim de verificar as alterações causadas pela fermentação com o fungo Rhizopus oligosporus, utilizado para obtenção do tempeh, e o efeito dos processos de secagem por torra controlada e liofilização sobre a farinha final obtida. Os resultados obtidos das farinhas de tempeh demonstraram um aumento nos teores de proteínas para todas as cultivares, com destaque para a BRS 216, que obteve valores finais de 57,36 g.100g-1 e 59,30g.100g-1 nos tempeh torrado e liofilizado, respectivamente. Foi verificada também redução dos teores de carboidratos totais, causada principalmente pela solubilização em água durante o processo de obtenção do tempeh, e uma elevada taxa de conversão dos compostos isoflavonóides, com aumento dos teores de agliconas (formas ativas para o organismo humano) para o tempeh liofilizado e torrado em todas as cultivares avaliadas, tendo a BRS 267 obtido o maior teor final de agliconas. Por esta razão, a BRS 267 foi escolhida para obtenção das farinhas mistas de soja e tempeh torrado/liofilizado, e para os testes de formulação do biscoito, que foi avaliado quanto à composição proximal, teor de agliconas, perfil de ácidos graxos e testes sensoriais de aceitação e intenção de compra. Os resultados desta segunda etapa comprovaram a manutenção do teor de ácido linolênico, importante para redução dos riscos de doenças coronarianas, além do ganho nos teores de agliconas quando utilizada a farinha de tempeh. Houve também alterações nos teores de proteínas e lipídios e, nos testes sensoriais, ficou evidenciada a semelhança entre as formulações, com notas satisfatórias para os atributos de aroma, sabor, textura e aceitação global dos biscoitos com farinha de soja e tempeh, quando comparadas ao biscoito contendo apenas farinha de soja. A intenção de compra também foi positiva, o que indica a torra como processo simples e economicamente viável para processamento do tempeh, e obtenção de uma farinha rica em proteínas e isoflavonas agliconas, que pode ser empregada como substituinte parcial à farinha de soja em biscoitos e outros produtos de panificação. / In this study, the benefits and application of tempeh flour as an alternative for soybean flour were evaluated. In the first stage, proximal composition, aglycone and total isoflavone content were analyzed in the soybean and tempeh flour. Grains of cultivars BRS 216, BRS 257 and BRS 267 were tested, in order to verify the effects of Rhizopus oligosporus, which is used for tempeh fermentation, plus the drying methods of controlled toasting and lyophilization, over the final flour. The results for tempeh flour showed an increase in protein content for all the cultivars, especially for BRS 216, which presented final values of 57.36g.100g-1and 59.30g.100g-1 for toasted and lyophilized tempeh flour, respectively. Total carbohidrates presented a reduction for all cultivars, mostly due to water solubilization during the process for tempeh preparation, and the isoflavone content showed a high conversion rate, with gains in aglycone levels (active forms for human consumption) for all lyophilized and toasted tempeh flours. BRS 267 showed the higher values for aglycone, reason to be chosen for the second part of the study, when mixed flour of soybean and lyophilized/toasted tempeh flour were obtained and applied in the formulation of coconut biscuits, which were evaluated for proximal composition, aglycone content, fatty acid profile and affective sensory analyses. Use of tempeh flour caused increase in aglycones level while linolenic acid content remained stable, which is important to reduce risks of coronary diseases. Lipids and protein contents also showed differences, and the sensory analysis demonstrated similarity between the biscuits, with satisfactory scores in aroma, flavor, texture and overall acceptability for cookies containing soy and tempeh flour, when compared to the cookie formulated with soy flour only. Purchase intention was also positive for both, which indicates roasting process, a simple and economically feasible drying method, for processing tempeh to a flour. This ingredient, rich in protein and aglycone isoflavones, important for human health, can be used as a partial substitute for soybean flour in cookies and other bakery products.