Master of Science / Department of Food, Nutrition, Dietetics and Health / Edgar Chambers IV / Sensory analysis techniques play a key role in the pet food industry to ensure the final product meets both the pets’ and pet owners’ demands and expectations. To date, the study of the pet owners’ perception towards pet foods is still an emerging field of study and a few number of publications have been released on the topic. In particular, little research has been conducted on exploring the pet owners’ perception regarding the appearance of pet foods. The objective of this work is to study the effect of the visual characteristics of dry dog food on the acceptability and perception by consumer segments of dog owners in the US and in Poland and to explore whether differences exist within countries and across the two countries. For this purpose, dog owners in both locations evaluated the appearance of thirty dry dog food samples with varying visual properties. The participants rated their degree of acceptability towards the appearance of the samples with four different attributes using 9-point hedonic scales. Also, the consumers were asked to associate each one of the samples with a list of positive and negative beliefs on a check-all-that-apply question. Cluster Analysis, ANOVA, and Correspondence Analysis were used to analyze the consumer feedback. The results demonstrate that the acceptability of the appearance of dry dog food is affected by the number of different kibbles present, color(s), shape(s), and size(s) in the product. Similarities were found both within countries and across countries and consumer segments. Consumers overall showed a preference for single-kibble samples of medium brown colors, medium kibble sizes, low-dimensional contrast kibbles and traditional kibble shapes. Furthermore, extra-small or extra-large sized kibble sizes and kibble shapes with a high-dimensional contrast were rejected by the consumers overall. In addition, differences across consumer segments within countries and across countries were identified from the results. The findings indicate that this topic have possibly been overlooked and opportunities for further research on this field are identified. Dry dog food manufacturers should take special consideration with the appearance of their products to enhance the acceptability by dog owners. The outcome of this work can help to drive dry dog food companies meet consumers’ needs and demands in a constantly changing pet food market, with benefits anticipated to the pet food industry and the wellbeing of dog owners.

No description available.

No description available.

Naphthenic acids (NAs), a group of compounds found in oil sands process-affected waters, have been implicated as a cause of the atypical odors which characterise fish taint. Sensory analyses were undertaken to clarify the role of NAs in fish taint. Triangle test and three-alternative forced choice (3-AFC) methods were used to estimate olfactory detection thresholds of NAs. Due to cognitive advantages, the 3-AFC method was found to be superior for the estimation of olfactory detection thresholds of NAs. 3-AFC analyses by trained panels of two commercial preparations and one oil sands extract of NAs, revealed that the odor detection thresholds and odor profiles of NAs differ markedly depending upon their source. Consumer preference panels revealed no evidence that the taste of fish collected from the Athabasca River was preferred less than the taste of fish from two other water basins in Alberta. / Food Science and Technology

Master of Science / Department of Food, Nutrition, Dietetics and Health / Edgar Chambers IV / Smoking of food is one of the oldest methods of food preservation and still is used widely to help preserve foods such as meats, fish and cheeses. Apart from its conservation function, the smoking process also has a considerable influence on the sensory characteristics of the products. A highly trained, skilled descriptive sensory panel identified, defined and referenced 14 attributes related to the flavor of food products labeled as smoked or smoky. The lexicon included: Smoky (Overall), Ashy, Woody, Musty/Dusty, Musty/Earthy, Burnt, Acrid, Pungent, Petroleum-Like, Creosote/Tar, Cedar, Bitter, Metallic and Sour. Definitions of these attributes were written and references were found that anchor a 0-15 point scale. This lexicon was used to evaluate the differences among smoked products under different circumstances such as products on the market versus products smoked at home, different woods used to smoke products and the length of time a product spends in the smoker. There are many methods used to impart this smoky flavor and due to health, environmental and economic concerns, many producers use nontraditional methods while hobbyists thrive on the traditional methods. Descriptive analysis was used to see if there are differences between products smoked using an at-home smoker and market products. Using principal component analysis, cluster analysis and analysis of variance, it was found that market products were significantly different than products smoked using an at home smoker. The market products were significantly more Sour and less Smoky, Ashy, Woody, Musty/Dusty and Acrid. Many types of woods are used to smoke products and many market products distinguish themselves based on the wood used. Six highly trained panelists evaluated pork that was smoked with either hickory, mesquite, cherrywood or Applewood and was smoked for 1, 2 or 4 hours. The flavor profiles of the smoke flavor was similar between the types of woods although as the length of time in the smoker increased and the intensities of most attributes rose, the differences among products smoked with different woods became more pronounced. Apple wood smoked products had higher intensities for Overall Smoky, Ashy, Burnt, Pungent, Petroleum-Like, Creosote/Tar and Cedar, while cherry wood smoked products had lower intensities for all attributes. Hickory and Mesquite smoked products were not significantly different from each other and typically scored between the other two woods. Smoking is a slow process and many popular restaurants that smoke their own products find that their claims of smoking for long periods of time are beneficial to their image. Descriptive analysis was used to see how the flavor changes based on the length of time the product (pork) was in the smoker. The samples of pork ranged from not smoked to smoked for 15 hours, with samples at every 2.5 hour increment. For most attributes, the intensities went up with the amount of time the product was in the smoker. The only exceptions were Musty/Earthy and Sour. The regression analysis revealed that Smoky, Ashy, Acrid, Creosote/Tar and Bitter are all at least moderately correlated with the time the product spent in the smoker.

Orientador: Walkíria Hanada Viotto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T19:46:50Z (GMT). No. of bitstreams: 1 Antunes_VeridianadeCarvalho_D.pdf: 594153 bytes, checksum: 10f4a5a4748fcd7e3ce583bf9de1f46f (MD5) Previous issue date: 2013 / Resumo: A extensão da vida de prateleira do leite pasteurizado é um desafio e uma necessidade para a indústria de laticínios. A microfiltração tem sido utilizada para remoção de micro-organismos e aumento da qualidade e vida de prateleira de leite fluido, sendo geralmente realizada em membranas cerâmicas sob o conceito de Pressão Transmembranar Uniforme (PTU). O objetivo desse trabalho foi avaliar o desempenho de um novo tipo de membrana (Isoflux®) capaz de manter o fluxo de permeado constante ao longo do comprimento da membrana e também o efeito do armazenamento refrigerado e da microfiltração na qualidade e vida útil do leite pasteurizado. O desempenho da membrana Isoflux , na microfiltração do leite cru, foi avaliado através da determinação do fluxo de permeado, retenção de células somáticas, microorganismos, gordura e caseína. Em geral, o fluxo da membrana estudada foi baixo, variando de 130 a 200 Kg/h/m2. A retenção de micro-organismos mesófilos e psicrotróficos foi maior que 99%, enquanto a retenção de coliformes foi de 90%, e de 100% para células somáticas. A membrana reteve, em média, 11,2% de caseína e 34,6% de gordura. O efeito do armazenamento refrigerado do leite cru (7 ºC/ 6 dias) e o impacto da microfiltração na microbiota, qualidade e vida de prateleira do leite pasteurizado foram avaliados pela contagem de micro-organismos mesófilos, psicrotróficos e coliformes, pelas alterações físicoquímicas (pH, acidez titulável e viscosidade), atividade proteolítica, ocorrência de sabor amargo e aceitação sensorial durante o tempo de armazenamento. Houve um aumento de 2,15 ciclos logarítmicos no número de micro-organismos mesófilos e de 2,55 ciclos para os psicrotróficos, após o armazenamento do leite cru a 7 °C/6 dias. Durante esse tempo, não houve alteração na composição do leite e sua viscosidade permaneceu constante. A microfiltração reduziu em 3 e 4 ciclos logarítmicos a contagem inicial de micro-organismos mesófilos e psicrotróficos, respectivamente. Não foi observada diferença significativa na atividade proteolítica, na viscosidade e no perfil sensorial do leite microfiltrado pasteurizado, durante a vida de prateleira do produto. O produto apresentou boa aceitação sensorial com média de 6,31 para o atributo sabor, sendo que mais de 50 % dos provadores certamente ou provavelmente comprariam o produto, durante toda sua vida de prateleira, independente de ser obtido de leite controle ou com armazenamento refrigerado prévio (7 °C/6 d). O gosto amargo aumentou com o tempo de armazenamento, mas não atingiu níveis que resultassem em rejeição do produto. Aos 15 dias de armazenamento refrigerado, o leite microfiltrado pasteurizado atingiu uma contagem de micro-organismos mesófilos de 3 x 104UFC/mL, o que determinou o fim da sua vida de prateleira. A microfiltração aliada à pasteurização proporcionou a obtenção de um produto com maior vida útil de prateleira, mesmo quando proveniente de leite cru refrigerado armazenado a 7 ºC por 6 dias / Abstract: Extending the shelf life of pasteurized milk is a challenge and a necessity for the dairy industry. The microfiltration has been utilized for the removal of microorganisms and increase the quality and shelf life of liquid milk, usually being held in ceramic membranes under the concept of uniform transmembrane pressure. A new membrane, Isoflux , with modified thickness of the separating layer, is claimed to maintain a nearly constant permeate flux along the length of the membrane. The performance of membrane Isoflux on the microfiltration of skim milk and the influence of concentration factor on the components retention by the membrane was evaluated. Permeate flux, reduction of bacteria and somatic cells, and partition of the main components of milk permeate and retentate during milk Microfiltration (MF) were determined. In general, the flux of membrane studied was low, varying with 130 a 200 Kg/h/m². The retention of mesophilic and psychrotrophic microorganisms was greater than 99%, 90% for coliforms, and 100% of somatic cells. The membrane retained, on average, 11.2% of casein and 34.6% fat. In general, the flux of the Isoflux® membrane was low, ranging 130-200 Kg/hm2. The new technical regulations require that raw milk is refrigerated on the farm. The effect of refrigerated storage of raw milk and the impact of the microfiltration on the microbiological quality and shelf life of pasteurized milk was assessed by bacterial counts (mesophilic, psychrotrophic and coliforms), physico-chemical changes (pH, titratable acidity, viscosity), proteolytic activity, the development of bitter taste and sensory acceptance during the storage time. There was an increase of 2.15 log in the number of mesophilic bacteria and of 2.55 log for psychrotrophic microrganisms after the storage of raw milk to 7 ° C/6 days. No changes in raw milk composition and viscosity occurred during the refrigerated storage. The microfiltration reduced by 3 log the initial count of mesophilic and up to 4 log the number of psychrotrophic microorganisms. There was no significant proteolytic activity, nor changes in viscosity or relevant sensory changes that might interfere with the sensory acceptance of microfiltered pasteurized milk during the 15 days of storage. The product had good acceptability with an average of 6.31 for the attribute flavor, with more than 50% of the panelists certainly or probably buy the product throughout its shelf life, whether it be milk obtained from control or refrigerated raw milk (7 ° C/6 d). The bitter taste increased with storage time, but did not reach levels that would result in rejection of the product. At 15 days of refrigerated storage, microfiltered pasteurized milk reached a mesophiles count of 3 x 104 CFU/mL, which determined the end of its shelf life / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos

Hemp is a plant containing many active substances and it is widely used in industry. The most common applications are the food, pharmaceutical, textile and cosmetics industries. This diploma thesis dealt with the characterization of hemp fractions, which are created during hemp processing and their potential applications. The theoretical part was focused on the description of the plant, its chemical composition and the research of the active substances in hemp. Also, its industrial use, the technique of hemp processing and the current applications of individual fractions were summarized. In the experimental part, hemp fractions were analysed in terms of nutrient content. Hemp extracts were prepared using three solvents - hexane, 70% ethanol and distilled water, which were compared based on the extraction yield of polyphenols, flavonoids, antioxidants, chlorophylls and cannabinoids. Antimicrobial effects were analysed in hexane and ethanol extracts. By-products of hemp processing were used in some screening application in biotechnology, cosmetics and nutrition. The results show that the extract with 70% ethanol had the highest content of active substances. From the hemp fractions, hemp trichomes and Fedora flowers had the highest content of active substances. Cannabis by-products have the potential to become valuable substrates for yeast cultivation. Face scrub containing hemp flour as an abrasive component had favourable results and was acceptable to consumers, as was the prepared hemp flour raw bar, which was evaluated to be comparable to commercially available hemp protein raw bars.

This diploma thesis deals with the sensory evaluation of selected types of non-chocolate sweets. In the theoretical part the production technology of non-chocolate sweets is described, including raw materials needed. Furthermore, basics of sensory analysis with characteristics of sensory evaluation and selected sensory methods are mentioned. The experimental part deals with the sensory evaluation itself; the selected sensory methods were applied on samples of gummy sweets. Four colours/flavours (strawberry, orange, lemon, apple) from five producers were chosen for evaluation, together 20 samples. The aim was to assess the differences in sensory quality of samples of the same type from different producers. Untrained assessors, from Faculty of Chemistry BUT, were invited for sensory evaluations. Significant differences were found among the samples, glossy appearance and pleasant characteristic taste contributed to the positive evaluation, on the contrary the rigid texture, bland taste and odour and possible off-flavour contributed to the negative evaluation.

Made available in DSpace on 2014-06-11T19:31:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-28Bitstream added on 2014-06-13T19:01:20Z : No. of bitstreams: 1 guaglianoni_dg_dr_arafcf.pdf: 445249 bytes, checksum: 6b2f7be0315d0559a22a0c696a31b5bc (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Ministério da Ciência, Tecnologia e Inovação (Mcti) / A partir do início dos anos 70, ficou estabelecido que a qualidade sensorial é o resultado da interação entre o alimento e o homem, portanto varia de forma subjetiva. Diferentes escalas foram então associadas às análises sensoriais, surgindo como conseqüência procedimentos estatísticos específicos nesta área. Os experimentos envolvendo análise sensorial iniciaram assim a discussão quanto ao número necessário de julgadores, ao seu treinamento e aos procedimentos apropriados à análise dos dados extraídos dessas escalas ordenadas. Este trabalho foi baseado em um teste sensorial de aceitação do atributo “Impressão Global” de quatro amostras de cachaças avaliadas por 120 julgadores. O objetivo fundamental foi realizar comparações entre os procedimentos estatísticos, paramétricos ou não-paramétricos, com vistas a compará-los e estabelecer o número mínimo de julgadores. Com base nos dados dos testes sensoriais foram criadas 5400 amostras sistemáticas com números diferentes de julgadores, sobre as quais foram aplicados os procedimentos estatísticos estabelecidos. Os resultados assim obtidos mostraram ser possível a utilização de um número menor de julgadores. Revelaram ainda que, na maioria dos casos, o índice de concordância é o fator mais importante na determinação do número mínimo de julgadores, sendo que, para valores de concordância de Kendall maior ou igual a 0,18, o número de 60 julgadores mostrou-se suficiente. / Since begin of 1970s, it was well established that the sensory quality of a food was a result of the interaction between the food and humans, thus varying subjectively. This led to the creation of scales associated to sensory analyses, end as a consequence, specific statistical procedures in this area. The experiments related to sensory analysis started the discussion about the number of judges required, their training, and the appropriate procedures for the analysis of data extracted from these ordered scales. The present work was based on a sensory acceptance test of the attribute “Global Impression” cachaça samples evaluated by 120 judges. The basic objective was to compare the standard statistical procedures, parametric and nonparametric, in order to determine the minimum number of judges necessary. From the initial data, 5400 systematic samples with different numbers of judges were created, and the standard statistical procedures were applied. Bored on the obtained data it was evaluated if the base experiment could be reproduced with fewer judges. The results indicated that, in most cases, the index of agreement is the most important factor to determine the necessary number of judges. In this case, if the Kendall concordance value among judges is ≥ 0,18, the total number of judges could be only 60.

Resumo: A partir do início dos anos 70, ficou estabelecido que a qualidade sensorial é o resultado da interação entre o alimento e o homem, portanto varia de forma subjetiva. Diferentes escalas foram então associadas às análises sensoriais, surgindo como conseqüência procedimentos estatísticos específicos nesta área. Os experimentos envolvendo análise sensorial iniciaram assim a discussão quanto ao número necessário de julgadores, ao seu treinamento e aos procedimentos apropriados à análise dos dados extraídos dessas escalas ordenadas. Este trabalho foi baseado em um teste sensorial de aceitação do atributo "Impressão Global" de quatro amostras de cachaças avaliadas por 120 julgadores. O objetivo fundamental foi realizar comparações entre os procedimentos estatísticos, paramétricos ou não-paramétricos, com vistas a compará-los e estabelecer o número mínimo de julgadores. Com base nos dados dos testes sensoriais foram criadas 5400 amostras sistemáticas com números diferentes de julgadores, sobre as quais foram aplicados os procedimentos estatísticos estabelecidos. Os resultados assim obtidos mostraram ser possível a utilização de um número menor de julgadores. Revelaram ainda que, na maioria dos casos, o índice de concordância é o fator mais importante na determinação do número mínimo de julgadores, sendo que, para valores de concordância de Kendall maior ou igual a 0,18, o número de 60 julgadores mostrou-se suficiente. / Abstract: Since begin of 1970s, it was well established that the sensory quality of a food was a result of the interaction between the food and humans, thus varying subjectively. This led to the creation of scales associated to sensory analyses, end as a consequence, specific statistical procedures in this area. The experiments related to sensory analysis started the discussion about the number of judges required, their training, and the appropriate procedures for the analysis of data extracted from these ordered scales. The present work was based on a sensory acceptance test of the attribute "Global Impression" cachaça samples evaluated by 120 judges. The basic objective was to compare the standard statistical procedures, parametric and nonparametric, in order to determine the minimum number of judges necessary. From the initial data, 5400 systematic samples with different numbers of judges were created, and the standard statistical procedures were applied. Bored on the obtained data it was evaluated if the base experiment could be reproduced with fewer judges. The results indicated that, in most cases, the index of agreement is the most important factor to determine the necessary number of judges. In this case, if the Kendall concordance value among judges is ≥ 0,18, the total number of judges could be only 60. / Orientador: João Bosco Faria / Coorientador: John Raymond Piggott / Banca: Elizeu Antonio Rossi / Banca: Romeu Magnani / Banca: Antonio Carlos Simões Pião / Banca: Eliete Vaz de Faria / Doutor