The use of quadratic discriminant analysis (QDA) or its regularized version (RQDA) for classification is often not recommended, due to its well-acknowledged high sensitivity to the estimation noise of the covariance matrix. This becomes all the more the case in unbalanced data settings for which it has been found that R-QDA becomes equivalent to the classifier that assigns all observations to the same class. In this paper, we propose an improved R-QDA that is based on the use of two regularization parameters and a modified bias, properly chosen to avoid inappropriate behaviors of R-QDA in unbalanced settings and to ensure the best possible classification performance. The design of the proposed classifier builds on a refined asymptotic analysis of its performance when the number of samples and that of features grow large simultaneously, which allows to cope efficiently with the high-dimensionality frequently met within the big data paradigm. The performance of the proposed classifier is assessed on both real and synthetic data sets and was shown to be much higher than what one would expect from a traditional R-QDA.

No description available.

Video Imaging Vehicle Detection Systems (VIVDS) are steadily becoming the dominant method for the detection of vehicles at a signalized traffic approach. This research is intended to investigate the improvement of a queue and delay estimation algorithm (QDA), specifically the queue detection of vehicles during the red phase of a signal cycle. A previous version of the QDA used a weighted average technique that weighted previous estimates of queue length along with current measurements of queue length to produce a current estimate of queue length. The implementation of this method required some effort to calibrate, and produced a bias that inherently estimated queue lengths lower than baseline (actual) queue lengths. It was the researcher’s goal to produce a method of queue estimation during the red phase that minimized this bias, that required less calibration, yet produced an accurate estimate of queue length. This estimate of queue length was essential as many other calculations used by the QDA were dependent upon queue growth and length trends during red. The results of this research show that a linear regression method using previous queue measurements to establish a queue growth rate, plus the application of a Kalman Filter for minimizing error and controlling queue growth produced the most accurate queue estimates from the new methods attempted. This method was shown to outperform the weighted average technique used by the previous QDA during the calibration tests. During the validation tests, the linear regression technique was again shown to outperform the weighted average technique. This conclusion was supported by a statistical analysis of data and utilization of predicted vs. actual queue plots that produced desirable results supporting the accuracy of the linear regression method. A predicted vs. actual queue plot indicated that the linear regression method and Kalman Filter was capable of describing 85 percent of the variance in observed queue length data. The researcher would recommend the implementation of the linear regression method with a Kalman Filter, because this method requires little calibration, while also producing an adaptive queue estimation method that has proven to be accurate.

This thesis compares the performance and robustness of five different varities of discriminant analysis, namely linear (LDA), quadratic (QDA), generalized quadratic (GQDA), diagonal linear (DLDA) and diagonal quadratic (DQDA) discriminant analysis, under elliptical distributions and small sample sizes.  By means of simulations, the performance of the classifiers are compared against separation of mean vectors, sample size, number of variables, degree of non-normality and covariance structures. Results show that QDA is competitive under most settings, but can be outperformed by other classifiers with increasing sample size and when the covariance structures across classes are similar. Other noteworthy results include sensitivity of DQDA to non-normality and dependence of the performance of GQDA on whether sample sizes are balanced or not.

No description available.

Background: Manufacturers have used emulsifying salts universally in the processed cheese industry since James L. Kraft patented the first processed cheese in 1916. My objective was to find alternative ingredients to replace emulsifying salts in processed cheese formulations; the product would follow "clean-labeling" trends and lower the final formulation's sodium content. Materials and Methods: My experiments followed conventional processed cheese formulations to create experimental batches, which were compared to positive and negative controls for significance. Textural, rheological, and melting tests evaluated objective cheese parameters. We observed subjective sensory properties through qualitative descriptive analysis, consumer acceptance panels, and focus groups. Results: We found that aspartic acid, cysteine, and glutamic acid could functionally emulsify a processed cheese formulation, as seen in the Manuscript section of this thesis. Potential future applications can be found under the Optimization Research section of this thesis. Conclusions: Alternative ingredients can make a large change on the processed cheese industry to improve current manufacturing practices and the nutrition of food products. While optimization work can always improve upon formulations, we propose a few formulations that could serve to replace traditional processed cheese practices.

As indústrias beneficiadoras de frutas são responsáveis por gerar grandes quantidades de resíduos, entre eles, os do maracujá. A polpa do maracujá é um dos principais produtos comercializados a partir da fruta, sendo as cascas e sementes os subprodutos resultantes de seu processamento. O objetivo deste trabalho foi desenvolver iogurte com adição de polpa e farinha de maracujá elaborada a partir dos subprodutos da industrialização da fruta. No total, foram avaliadas sete amostras de iogurte dentre as quais cinco apresentavam em sua composição a farinha de maracujá. Foram realizadas análises físico-químicas, microbiológicas, verificação de resíduos de agrotóxicos, teste de aceitação sensorial, verificação da intenção de compra, análise descritiva quantitativa (ADQ), estimativa da vida útil e elaboração dos rótulos dos produtos. Todos os iogurtes adicionados de farinha apresentaram elevados teores de fibra alimentar. Não foram detectados resíduos de agrotóxicos nas amostras do subproduto do maracujá. Observou-se que a incorporação da farinha de maracujá apresentou efeitos positivos na viscosidade e teor de minerais do iogurte, e negativos para aspectos como cor e pH. Verificou-se maior aceitação dos provadores para o iogurte sem adição de farinha. No entanto, o iogurte com baixa concentração do ingrediente (iogurte 2%) também apresentou aceitação satisfatória e intenção de compra relevante. A partir da ADQ, comprovou-se que a adição da polpa e da farinha de maracujá influenciou o perfil sensorial das amostras de iogurte, sendo que, os tratamentos com 2% e 4% de farinha, foram os que apresentaram maiores notas para a maioria dos atributos desejáveis para um iogurte sabor maracujá enriquecido com fibras. O tempo de vida útil do produto foi estimado em 21 dias, sendo que durante o armazenamento, observou-se elevação das taxas de sinérese, crescimento de fungos e leveduras, decréscimo do pH e do número de bactérias láticas viáveis nas amostras. Levando em consideração os dados obtidos, o iogurte com adição de 2% de farinha de maracujá foi considerado o produto mais viável para elaboração / The fruit-processing industries are responsible for generating large quantities of residues, like passion fruit byproduct. The pulp of the passion fruit is one of the main products from the fruit, and the peels and the seeds are the main byproduct resulting from its processing. The aim of this study was to develop a yogurt with passion fruit pulp and flour produced from byproduct of industrialization of fruit. In total, seven samples were evaluated yogurt among which five had flour of passion fruit in their composition. It was perfomed by physico-chemical analyses, microbiological, pesticide residue, acceptability test and purchase intent, quantitative descriptive analysis (QDA), the estimated of useful life and development of product labels. All yogurts with flour showed high levels of dietary fiber. No pesticide residues were detected in byproducts of passion fruit samples. It was observed that the incorporation of passion fruit flour showed positive effects on the mineral content and viscosity but negative aspects such as color and pH. A greater acceptance was observed for yoghurt without flour. However, the yogurt with low concentration of this ingredient (yogurt 2%) also showed satisfactory acceptance and relevant purchase intent. The ADQ showed that the addition of the pulp and passion fruit flour influenced the sensory profile of the samples. The treatments with 2% and 4% flour presented the highest scores in the most desirable attributes for a passion fruit yogurt enriched with fiber. The useful life of the product was estimated at 21 days, and during storage, it was observed increase the rate of syneresis, fungal and yeast growth, decreasing of the pH and the number of viable lactic acid bacteria in samples. Taking into account the data obtained, the yogurt with the addition of 2% of flour of passion fruit was more viable than the others

No Brasil há espécies frutíferas pouco exploradas, que representam oportunidade aos produtores para acessarem mercados especiais, onde consumidores valorizam o caráter exótico e a presença de nutrientes capazes de prevenir doenças degenerativas. Nesse contexto, a palmeira juçara, originária da Mata Atlântica, por muito tempo explorada apenas para a retirada do palmito, atualmente, vem ganhando espaço pela polpa dos seus frutos. Sua cor roxa intensa se deve à presença das antocianinas, poderosos antioxidantes que atuam inibindo ou diminuindo os efeitos desencadeados pelos radicais livres. A polpa é altamente perecível sendo problemática sua conservação em temperatura ambiente, dificultando sua valorização no mercado. Diante disso, são necessárias tecnologias que minimizem perdas nutricionais e sensoriais a fim de produzir alimentos saudáveis, saborosos e duradouros. Este estudo consta de cinco experimentos com polpa de juçara, que objetivaram: avaliar a composição físicoquímica, mineral e lipídica; realizar a caracterização sensorial através da Análise Descritiva Quantitativa (ADQ); avaliar a conservação físico-química e sensorial quando submetida à radiação gama, acidificação e pasteurização em tacho aberto e desidratação por atomização e liofilização. Os frutos foram obtidos no Parque das Neblinas (Mogi das Cruzes/SP) e despolpados no Departamento Agroindústria, Alimentos e Nutrição (ESALQ/USP). Verificou-se que a polpa de juçara é ótima fonte energética e dos minerais K, Fe, Co, Mg, Cu, Zn, Mn e Mo; é rica em antocianinas e em ácidos graxos de boa qualidade (palmítico, oleico e linoleico). A irradiação da polpa foi realizada no Instituto de Pesquisas Energéticas e Nucleares (IPEN - São Paulo, SP) com as doses 0,0; 2,5; 5,0; 7,5 e 10,0 kGy e armazenada a 6°C durante 30 dias (avaliações quinzenais). O referido processo não se mostrou promissor para a conservação do produto a 6°C, pois a degradação das antocianinas e compostos fenólicos foi acelerada e a cor alterada de roxo para marrom, além de não ter sido bem aceita sensorialmente. Ainda, foram estudadas oito combinações entre acidificação (pH<4,0), pasteurização (85°C/5 min.) e armazenamento a 6°C e -18°C, durante 60 dias, com análises quinzenais. A polpa pasteurizada e acidificada foi a que melhor manteve as características físico-químicas e sensoriais, sendo a temperatura de congelamento a variável de melhor resultado. A avaliação da qualidade da polpa desidratada por atomização e liofilização, embalada em bolsas de polietileno (PE) e polietileno revestido com camada de alumínio (PA) durante 120 dias em temperatura ambiente e ao abrigo da luz, revelou que ambos os processos conferiram qualidade físico-química satisfatória e conservação durante o armazenamento, sendo a embalagem PA a mais adequada devido à menor absorção de umidade e prevenção da oxidação. Sensorialmente, como suco reconstituído e adicionado de banana nanica e açúcar, a polpa de juçara liofilizada foi a mais bem aceita. Para a ADQ, foi treinada equipe para a avaliação de amostras congeladas e pasteurizadas pós-embalagem (85°C/5 min.) armazenadas sob refrigeração e congelamento, visando-se obter o perfil sensorial de cada uma. A polpa pasteurizada congelada foi a que apresentou melhores características sensoriais, sendo descrita como aerada, pouco heterogênea, sabor pouco amargo e pouco adstringente / In Brazil there are unexplored fruit species, which represent an opportunity for producers to access special markets, where consumers appreciate the exotic character and presence of nutrients capable of preventing degenerative diseases. In this context, juçara palm (Euterpe edulis), native of the Atlantic Forest, has long been explored only for the removal of the stem, but currently the pulp of its fruit is becoming more popular. The intense purple color is due to the presence of anthocyanins, powerful antioxidants that act by inhibiting or decreasing the effects unleashed by free radicals. The pulp is highly perishable and its preservation is impossible at room temperature, lowering its market value in sales. In face of this, we need technologies that minimize nutritional and sensorial losses in order to produce healthy, tasty and long lasting foods. This study consists of five experiments with juçara pulp, which aimed to: evaluate the physico-chemical, mineral and lipid composition; realize the sensory characterization by Quantitative Descriptive Analysis (QDA); evaluate the physico-chemical and sensory conservation when submitted to radiation gamma, acidification and pasteurization, and dehydration by spray and freeze drying. The fruits have been obtained at Parque das Neblinas (Mogi das Cruzes/SP) and depulped at Agribusiness, Food and Nutrition Department (ESALQ/USP). Was verified that juçara pulp is excellent source of energy and minerals K, Fe, Co, Mg, Cu, Zn, Mn and Mo; rich in anthocyanins and fatty oils of good quality (palmitic, oleic and linoleic). The irradiation of pulp was performed at the Institute of Energy and Nuclear Research (IPEN - São Paulo, SP) at doses 0,0, 2,5, 5,0, 7,5 and 10,0 kGy and stored at 6°C for 30 days (fortnightly assessments). That process was not promising for the conservation of the product at 6°C, because the degradation of anthocyanins and phenolic compounds was accelerated and the color changed from purple to brown, in addition to lacking been accepted sensorially. Further, eight combinations have been studied among acidification (pH<4.0), pasteurization (85°C/5 min.) and storage at 6°C and -18°C for 60 days with biweekly tests. The pasteurized and acidified pulp was that best maintained the physicochemical and sensory characteristics, and the freezing storage was the variable of the better result. The evaluation of quality pulp dehydrated by freeze and spray drying, packaged in bags of polyethylene (PE) and polyethylene-coated aluminum layer (PA) for 120 days at room temperature and protected from light, revealed that both processes conferred physicochemical quality satisfactory and conservation during storage, the packaging PA is the most suitable due to lower absorption of moisture and prevention of oxidation. Sensorially, as reconstituted juice and added to sugar and banana nanica, juçara pulp freeze dried was the more accepted. For the QDA have been trained team for the evaluation of frozen and postpackaging pasteurized samples (85°C/5 min.) stored under refrigeration and freezing, in order to obtain the sensory profile of each. The frozen pasteurized pulp presented the best sensory characteristics, being described as aerated, slightly heterogeneous, taste slightly bitter and slightly astringent

No Brasil há espécies frutíferas pouco exploradas, que representam oportunidade aos produtores para acessarem mercados especiais, onde consumidores valorizam o caráter exótico e a presença de nutrientes capazes de prevenir doenças degenerativas. Nesse contexto, a palmeira juçara, originária da Mata Atlântica, por muito tempo explorada apenas para a retirada do palmito, atualmente, vem ganhando espaço pela polpa dos seus frutos. Sua cor roxa intensa se deve à presença das antocianinas, poderosos antioxidantes que atuam inibindo ou diminuindo os efeitos desencadeados pelos radicais livres. A polpa é altamente perecível sendo problemática sua conservação em temperatura ambiente, dificultando sua valorização no mercado. Diante disso, são necessárias tecnologias que minimizem perdas nutricionais e sensoriais a fim de produzir alimentos saudáveis, saborosos e duradouros. Este estudo consta de cinco experimentos com polpa de juçara, que objetivaram: avaliar a composição físicoquímica, mineral e lipídica; realizar a caracterização sensorial através da Análise Descritiva Quantitativa (ADQ); avaliar a conservação físico-química e sensorial quando submetida à radiação gama, acidificação e pasteurização em tacho aberto e desidratação por atomização e liofilização. Os frutos foram obtidos no Parque das Neblinas (Mogi das Cruzes/SP) e despolpados no Departamento Agroindústria, Alimentos e Nutrição (ESALQ/USP). Verificou-se que a polpa de juçara é ótima fonte energética e dos minerais K, Fe, Co, Mg, Cu, Zn, Mn e Mo; é rica em antocianinas e em ácidos graxos de boa qualidade (palmítico, oleico e linoleico). A irradiação da polpa foi realizada no Instituto de Pesquisas Energéticas e Nucleares (IPEN - São Paulo, SP) com as doses 0,0; 2,5; 5,0; 7,5 e 10,0 kGy e armazenada a 6°C durante 30 dias (avaliações quinzenais). O referido processo não se mostrou promissor para a conservação do produto a 6°C, pois a degradação das antocianinas e compostos fenólicos foi acelerada e a cor alterada de roxo para marrom, além de não ter sido bem aceita sensorialmente. Ainda, foram estudadas oito combinações entre acidificação (pH<4,0), pasteurização (85°C/5 min.) e armazenamento a 6°C e -18°C, durante 60 dias, com análises quinzenais. A polpa pasteurizada e acidificada foi a que melhor manteve as características físico-químicas e sensoriais, sendo a temperatura de congelamento a variável de melhor resultado. A avaliação da qualidade da polpa desidratada por atomização e liofilização, embalada em bolsas de polietileno (PE) e polietileno revestido com camada de alumínio (PA) durante 120 dias em temperatura ambiente e ao abrigo da luz, revelou que ambos os processos conferiram qualidade físico-química satisfatória e conservação durante o armazenamento, sendo a embalagem PA a mais adequada devido à menor absorção de umidade e prevenção da oxidação. Sensorialmente, como suco reconstituído e adicionado de banana nanica e açúcar, a polpa de juçara liofilizada foi a mais bem aceita. Para a ADQ, foi treinada equipe para a avaliação de amostras congeladas e pasteurizadas pós-embalagem (85°C/5 min.) armazenadas sob refrigeração e congelamento, visando-se obter o perfil sensorial de cada uma. A polpa pasteurizada congelada foi a que apresentou melhores características sensoriais, sendo descrita como aerada, pouco heterogênea, sabor pouco amargo e pouco adstringente / In Brazil there are unexplored fruit species, which represent an opportunity for producers to access special markets, where consumers appreciate the exotic character and presence of nutrients capable of preventing degenerative diseases. In this context, juçara palm (Euterpe edulis), native of the Atlantic Forest, has long been explored only for the removal of the stem, but currently the pulp of its fruit is becoming more popular. The intense purple color is due to the presence of anthocyanins, powerful antioxidants that act by inhibiting or decreasing the effects unleashed by free radicals. The pulp is highly perishable and its preservation is impossible at room temperature, lowering its market value in sales. In face of this, we need technologies that minimize nutritional and sensorial losses in order to produce healthy, tasty and long lasting foods. This study consists of five experiments with juçara pulp, which aimed to: evaluate the physico-chemical, mineral and lipid composition; realize the sensory characterization by Quantitative Descriptive Analysis (QDA); evaluate the physico-chemical and sensory conservation when submitted to radiation gamma, acidification and pasteurization, and dehydration by spray and freeze drying. The fruits have been obtained at Parque das Neblinas (Mogi das Cruzes/SP) and depulped at Agribusiness, Food and Nutrition Department (ESALQ/USP). Was verified that juçara pulp is excellent source of energy and minerals K, Fe, Co, Mg, Cu, Zn, Mn and Mo; rich in anthocyanins and fatty oils of good quality (palmitic, oleic and linoleic). The irradiation of pulp was performed at the Institute of Energy and Nuclear Research (IPEN - São Paulo, SP) at doses 0,0, 2,5, 5,0, 7,5 and 10,0 kGy and stored at 6°C for 30 days (fortnightly assessments). That process was not promising for the conservation of the product at 6°C, because the degradation of anthocyanins and phenolic compounds was accelerated and the color changed from purple to brown, in addition to lacking been accepted sensorially. Further, eight combinations have been studied among acidification (pH<4.0), pasteurization (85°C/5 min.) and storage at 6°C and -18°C for 60 days with biweekly tests. The pasteurized and acidified pulp was that best maintained the physicochemical and sensory characteristics, and the freezing storage was the variable of the better result. The evaluation of quality pulp dehydrated by freeze and spray drying, packaged in bags of polyethylene (PE) and polyethylene-coated aluminum layer (PA) for 120 days at room temperature and protected from light, revealed that both processes conferred physicochemical quality satisfactory and conservation during storage, the packaging PA is the most suitable due to lower absorption of moisture and prevention of oxidation. Sensorially, as reconstituted juice and added to sugar and banana nanica, juçara pulp freeze dried was the more accepted. For the QDA have been trained team for the evaluation of frozen and postpackaging pasteurized samples (85°C/5 min.) stored under refrigeration and freezing, in order to obtain the sensory profile of each. The frozen pasteurized pulp presented the best sensory characteristics, being described as aerated, slightly heterogeneous, taste slightly bitter and slightly astringent

Apesar da citricultura brasileira deter a liderança mundial na produção de laranjas e de suco de laranja concentrado congelado (FCOJ, frozen concentrated orange juice), observa-se baixo consumo no mercado interno de frutos e de suco in natura, o preferido pelo consumidor brasileiro. Assim, há grande interesse no desenvolvimento de produtos, técnicas de produção e conservação específica para variedades de laranja. As indústrias que produzem suco de laranja a partir do processamento da fruta in natura, conhecido como suco pasteurizado não proveniente do suco concentrado, Not From Concentrate (NFC), enfrentam sérios problemas tecnológicos. As frutas apresentam variabilidade química e sensorial devido às características intrínsecas, podendo variar o sabor e aroma devido às diferentes variedades disponíveis ao longo do ano. O objetivo do presente trabalho foi otimizar o processo da radiação gama em suco de laranja, escolhendo a melhor dose, a fim de reduzir a contagem microbiana e não comprometer as características sensoriais e físico-químicas do suco. Definidas as doses, o objetivo foi avaliar as características microbiológicas, físico-químicas e sensoriais do suco de laranja proveniente de três variedades cítricas, submetido aos processos de pasteurização e irradiação e desenvolver uma terminologia descritiva e o perfil sensorial de suco de laranja. As amostras foram avaliadas por uma equipe treinada de nove provadores e avaliadas quanto à aceitação, com escala hedônica de sete pontos por cinquenta provadores. Tendo em vista os resultados obtidos, a radiação gama e a pasteurização contribuíram para a redução das contagens microbiológicas. No entanto, sensorialmente, os tratamentos com 4,5 e 6,0 kGy foram considerados abaixo do limite de aceitabilidade, quanto ao sabor e à impressão global. As doses estudadas mostraram reduzido impacto sobre as características físico-químicas, independente das variedades cítricas. O tratamento com 3,0 kGy resultou em suco com aroma e sabor acentuado de remédio e cozido, que provavelmente terão influência negativa na aceitabilidade do produto / The Brazilian citrus is the global leader in production of oranges and frozen concentrated orange juice (FCOJ) there is low domestic consumption of fruits and fresh juice, preferred by brazilian consumers. Thus, there is a great interest by development of products, processes and specific conservation to the cultivation of citrus varieties for the juice\'s production. The industries produce orange juice from the fresh fruit processing, known as pasteurized juice not from concentrate juice (NFC), have serious technological problems. The fruits have chemical and sensory variability due to intrinsic characteristics and can vary the flavor and smell of orange juice because the different varieties available throughout the year. The aim of this study was to optimize the process of gamma radiation in orange juice, picking the best dosage in order to reduce microbiological count and that doesn\'t compromise the sensory characteristics and physicochemical juice. Defined dosages, the objective was to evaluate the microbiological, physicochemical and sensory orange juice from different varieties subjected to pasteurization and irradiation and develop a descriptive terminology and sensory profile of orange juice. The sensorial attributes analysed in this study were appearance, smell, flavor and texture. The samples were evaluated by a trained painel of nine tasters and evaluated for acceptance, with seven-point hedonic scale for fifty tasters. In view of these results, gamma radiation and pasteurisation contributed to the reduction of microbiological counts. However, sensory, treatments with 4.5 and 6.0 kGy were considered the limit of acceptability for flavor and overall impression. The doses studied showed little impact on the physical and chemical characteristics, independent of the citrus varieties. Treatment with 3.0 kGy resulted in juice with aroma and sharp taste of medicine and baked, which will probably have a negative influence on the acceptability of the product