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The knowledge about thermophysical properties of foods is especially important in thermal processing, influencing the design, optimization and cost reduction of the process, as well as the quality and safety of the final product. This article deals with the determination of some thermophysical properties of yacon, namely, specific mass, specific heat, thermal conductivity and thermal diffusivity during the osmo-convective drying. Yacon is a root with approximately 90% w.b. of moisture content, whose high concentration of fructooligosacharydes and antioxidants has gained attention in the food research field. Yacon slices were osmotically dehydrated for 2 hours in a sucralose solution and then dried in a convective tray dryer for 2 hours, varying the osmotic solution’s temperature and stirring rate and temperature of the drying air. All thermophysical properties were determined during the drying process at 30-minute intervals. The thermophysical properties were determined not only experimentally but also calculated by models available in literature based on the product’s centesimal composition. A satisfactory agreement between experimental and predicted results was obtained. Further, empirical models obtained by nonlinear regression were successfully fitted to the experimental data, as a function of moisture content, within a 94% - 3% w.b. range.

The contents of total phenolics, flavonoids, and antioxidant activity of bee pollen ethanolic extract were determined and compared to those of commercial antioxidants. Bee pollen extract from the state of Rio Grande do Sul presented antioxidant activity statistically equal to that of α -tocopherol and higher than those of BHT and BHA. A statistically significant correlation was observed between the antioxidant activity and the total phenolics and total flavonoids contents of bee pollen extracts. HPLC technique made the identification of high contents of rutin and myricetin possible, which may partially explain the high antioxidant activity of Brazilian bee pollen.

The aim of this study was to determine the antioxidant activity, phenolic content and antibacterial activity of pollen extracts obtained with different concentrations of ethanol. Each extraction condition (ethanol solutions from 40 to 90%) had a different effect in the phenolic compounds content. Although, the pollen extract obtained at 60, 70 and 80% of ethanol showed relatively higher levels of phenolic compounds (>10 mg/g) and did not present statistical significant difference between the extraction conditions. The amount of total phenolics ranged from 3.6 to 8.1 and 6.6 to 10.9 mg GAE/g for Alagoas state and Parana state pollen, respectively. The higher value for antioxidant activity index was 83.30% for the pollen from Alagoas state and 81.15 % for Parana state pollen. The highest degree of antioxidant activity was found in the extraction at 60% of ethanol solution for Parana state pollen, which also showed the highest concentration of polyphenol compounds. Staphylococcus aureus was inhibited by the ethanolic extract of Alagoas state pollen in all the concentrations of solvent, except the ethanolic extract of pollen at 90%. The extract at 60% of ethanol solution (Parana sample) inhibited Bacillus subtilis, Pseudomonas aeruginosa and Klebsiella sp.Objetivou-se, neste estudo determinar compostos fenólicos, a atividade antioxidante a antibacteriana dos extratos etanólicos de pólen, obtidos com diferentes concentrações de etanol. As diferentes condições de extração (etanol de 40 a 90%) apresentaram diferentes efeitos no conteúdo dos compostos fenólicos extraídos. Os extratos de pólen obtidos com etanol a 60, 70 e 80% apresentaram maiores níveis de compostos fenólicos (>10 mg/g) e não apresentaram diferenças estatísticas entre essas condições de extração. A quantidade de compostos fenólicos nos extratos de pólen variou de 3.6 a 8.1 e 6.6 a 11 mg de equivalente em ácido gálico por g de pólen (GAE), para os estados de Alagoas e Paraná, respectivamente. Os maiores índices de atividade antioxidante para o pólen do estado de Alagoas foi de 83.30% e 81.15 % para o pólen do estado do Paraná. O pólen do estado do Paraná extraído com etanol a 60%, apresentou o maior índice de atividade antioxidante e também a maior concentração de compostos fenólicos. A bactéria Staphylococcus aureus foi inibida pelo extrato etanólico do pólen de Alagoas, em todas as concentrações, exceto no extrato etanólico a 90%. O extrato etanólico a 60%, no pólen do Paraná, inibiu Bacillus subtilis, Pseudomonas aeruginosa e Klebsiella sp.

Objetivou-se com este trabalho estudar experimentalmente o comportamento reológico da polpa de manga centrifugada na faixa de temperatura de 10°C a 60°C. As medidas reológicas foram feitas no reômetro Haake Rotovisco modelo RV 20, utilizando o sistema de medida de cilindros concêntricos. A polpa integral foi produzida em uma despolpadeira com tela de 1,6 mm, congelada em um congelador de placas e armazenada a -15ºC e centrifugada a 15000 rpm (29000 G), durante 40 minutos. O comportamento reológico da polpa de manga centrifugada (reogramas) foi ajustado pelo modelo de Ostwald de Waelle (Lei da Potência) e as curvas de viscosidade aparente ajustadas pelo modelo de Mizrahi-Berk. Observou-se um comportamento pseudoplástico para a polpa de manga centriguda (nThe aim of this work was to study experimentally the rheological behavior of mango pulp centrifuged in a temperature range of 10 to 60°C. The rheological measurements were carried out in a rheometer Haake Rotovisco model RV-20, using a measuring system of concentric cylinders. The whole pulp was produced in a depulper with a 1,6mm screen, being plate-frozen and stored at 15ºC and it was centrifuged at 15000rpm (29000 G) during 40 minutes. The rheological behavior of the centrifuged mango pulp was fitted to the Ostwald de Waelle model (Power Law) and the apparent viscosity curves were fitted by the Mizrahi-Berk model. It was observed a shear thinning behavior to the centrifuged mango pulp (n

Objetivou-se com este trabalho avaliar os efeitos de pré-tratamentos para a redução do escurecimento nas cultivares de maçã Fuji e Gala após um período de congelamento de 12 dias. Aplicou-se quatro pré-tratamentos: imersão em água fervente por dois minutos (IAF), imersão em solução de bissulfito 0,25% por dois minutos (ISB), imersão em solução de sacarose 35% por dois minutos (ISS) e um sem pré-tratamento para comparação (SPT). Procedeu-se a análise, em que avaliou-se a cor, através de medidas colorimétricas empregando a escala universal L*, a* e b* nas amostras tratadas antes e depois do congelamento. Para avaliação sensorial do atributo cor utilizou-se a análise descritiva quantitativa (ADQ) com escala estruturada de 9 pontos. O melhor pré-tratamento na prevenção do escurecimento foi o IAF e o pior foi o tratamento SPT, no qual se observou uma alta oxidação dos compostos fenólicos. O pré-tratamento ISB apresentou a maior aceitação no teste ADQ para as maçãs Fuji e Gala, não obtendo-se relação entre a análise física colorimétrica e a análise afetiva sensorial.The aim of this work was to evaluate the effect of pre-treatments in order to reduce the browning on Fuji and Gala apple varieties (Malus domestica Borkh), after a freezing period of 12 days. Four pre-treatments were applied: dip in boiling water for two minutes (DBW), dip in sodium bisulphite 0,25% for two minutes (DSB), dip in sucrose solution 35% for two minutes (DSS) and one without pre-treatment (WPT) to compare with the others. The color was evaluated through colorimetric assays, applying the universal scale L*, a* e b* at the treated samples before and after freezing. It was used the quantitative descriptive analysis (QDA), with structured scale of 9 points, to the sensorial evaluation of the color attribute. The best pre-treatment, in the browning prevention, was the DBW and the worst was the WPT, where it was observed a high oxidation of phenolic compounds. The pre-treatment DSB showed a higher acceptance at the DQA test on Fuji and Gala apple varieties, however it was not obtained a relation between colorimetric physical analysis and the affective sensorial analysis.

A alface crespa minimamente processada foi acondicionada em cinco tipos de sacos plásticos confeccionados com diferentes filmes (PEBD-50, PEBD-60, PEBD-100, BOPP - PEBD e Conservax), sob atmosfera ativamente modificada com 5% de O2 e 10% de CO2. Monitorou-se a atmosfera durante o armazenamento por meio da determinação das concentrações de O2 e CO2 no interior das embalagens. A determinação da vida útil baseou-se na avaliação da qualidade sensorial realizada por meio de Análise Descritiva Quantitativa ADQ, aplicando-se escala hedônica de nove pontos para aparência e cinco pontos para sabor, aroma e textura. Determinaram-se as taxas de permeabilidade ao O2 e CO2 e a espessura dos filmes. Nos filmes com baixas taxas de permeabilidade (BOPP-PEBD e Conservax) ocorreu rápida degeneração dos tecidos celulares e perda da qualidade da alface. Os filmes com maiores taxas de permeabilidade (PEBD-50 e 60) propiciaram a rápida redução do CO2. Entretanto, todas as embalagens com atmosfera modificada proporcionaram os melhores resultados permitindo que a alface mantivesse características adequadas de consumo em até dez dias de armazenamento.The lettuce was packaged in five different plastic films in bags forms (LDPE-50, LDPE -60, LDPE -100, BOPP-LDPE and Conservax-trade mark), under active modified atmosphere of 5% O2 and 10% CO2. It was accompanied the atmosphere changes with the determination of the O2 and CO2 concentration inside the package during the storage. The shelf life was determined through sensorial evaluation whit Descriptive Quantitative Analyses using a nine points hedonic scale to visual quality and five points hedonic scale to taste, flavor, and texture. Permeability and thickness films characteristics were analyzed. In the films with lowers permeability rates (BOPP- LDPE and Conservax) it was favored quickly cellular tissues degeneration and lettuce quality loss. The films with higher permeability rates (LDPE -50 and LDPE -60)favored quickly CO2 reduction. In spite of this, all the modified atmosphere packaging obtained the best results allowing to lettuce keep the adequate consume characteristics until ten days under storage.

Yacon juice is a worthy alternative of a product able to keep all the benefits of the yacon roots. Lactobionic acid has been studied as a food functional acidifier, although still without permission to be applied in foods, cannot be sensory evaluated. Thus, the only approach to estimate a sensory profile of a lactobionic acid-added product is correlating sensory data with chemometric assessments. Sensory evaluation of yacon juice was performed with flash profile and its results were correlated with E-nose ones. Sensometrics showed a high similarity between yacon juice with lactobionic acid and tartaric acid regarding the volatile signals, and both raised the descriptors: Astringency, yellow color pearl-like, herbal, soy, cereal and leaf flavor, acid and bitter residual flavors. This study showed not just the potential of yacon juice as a new product, but also the suitability of combining flash profile and sensometrics to access a potential ingredient.

Malic acid, a carboxylic acid most found in fruits, is a smooth taste substance used as flavoring and preservative agent in foods, although not as used as citric acid. There are no studies focusing in quantitative results or investigations on its physicochemical properties, useful to the food industry, or even the confirmation of its calcium chelating, buffer texturizer and antioxidant alleged properties. Thus, the aim of this work was the assessment of most physicochemical properties of malic acid, solid and in solution, that could be useful to the food industry understand its real potential. The following analyses were carried out: melting point; structure (NMR, XRD, FTIR and SEM/EDS); TGA/DTG; solubility, hygroscopicity; antioxidant activity, iron chelating and antibacterial activities and stability of pectin gels. The melting temperature found was 129.71 °C. TGA/DTG exhibited first loss of mass around 140 °C. In the temperature range of 10 to 55 °C, it exhibited a high solubility in water, from 48.12 to 61.49 (100w), respectively. The tested bacteria, related to food spoilage, were inhibited by DL-malic acid 10% or higher. Chelating and antioxidant activities showed expressive results even in 1% solution. Pectin gels with malic acid had stronger structure and less syneresis than citric acid gels. In addition, calcium chelating, buffer texturizer and antioxidant properties were confirmed. Thus, malic acid has potential to be applied in a wide variety of food products as fortified beverages, frozen and refrigerated items, oils, pectin gels, hard and soft candies, and biofilms, due to all the characteristics quantified.

Abstract This study aimed to evaluate the process of cellulose extraction from yacon stem using combined pulping and bleaching processes to produce nanofibrillated cellulose (NFC). First, a chemical pulping process with NaOH was applied and, subsequently, the pulp obtained was bleached. From the chemical pulp (CP) bleached, NFC was obtained by the mechanical defibrillation in a colloidal grinder. Then, chemical composition, and infrared analysis of the pulps were performed. The pulping process showed a lower amount of extractives and lignin content, as a low yield and an excessively dark pulp. The CP bleached with NaClO2 showed the best results increased whiteness of the pulp. A suspension of NFC with fibers of 5-60 nm in diameter, high crystallinity index, and thermal stability was obtained. The results are promising and demonstrate the technical feasibility of obtaining NFC from yacon stems waste which is ideal to apply to other materials of the industry.

O objetivo deste trabalho foi verificar a qualidade microbiológica de leite pasteurizado tipo B comercializado na cidade de Curitiba, PR, durante o período de vida útil. Nas amostras coletadas aleatoriamente em mercados, no momento em que eram colocados na gôndola, foram realizadas contagens de mesófilos, psicrotróficos, psicrotróficos proteolíticos e lipolíticos e a determinação da atividade de fosfatase alcalina e peroxidase. As amostras foram armazenadas sob refrigeração (5ºC) e nova contagem microbiana foi feita no término do prazo de validade do produto. Os resultados indicaram que durante o prazo de validade, houve elevação na contagem de mesófilos em 4 amostras. Em 7 amostras verificou-se a multiplicação de psicrotróficos.

This work was aimed at studying the influence of PFJ and/or sodium disulphite on Yacon pulp colour, and evaluating the sensory attributes of Yacon non-sugar pastes. A colour kinetic evaluation of browning in 11 treatments containing Yacon tubers, yellow passion fruit juice (PFJ) and/or sodium disulphite, over the course of 240 minutes was studied to inactivate the PPOs activity. The evaluation of the colour alterations of Yacon tuber by the addition of variable amounts of PFJ and sodium disulphite enabled identification of efficient treatments for the inhibition of browning: T7 (300 g kg -1 PFJ), T8 (400 g kg -1 PFJ), and T10 (150 g kg -1 PFJ + 0.25 g kg -1 sodium disulphite). These treatments presented high colour intensity (C*) and an insignificant (P

Este trabalho teve como objetivo verificar o efeito da carbonatação sobre a multiplicação de microrganismos e da viscosidade do leite cru durante o armazenamento refrigerado. Foi aplicado um planejamento fatorial 23 completo onde avaliou-se o efeito das variáveis pH (5,8 a 6,4), tempo (0 a 10 dias) e temperatura (5 a 10°C) de armazenamento do leite carbonatado sobre as respostas psicrotróficos, psicrotróficos proteolíticos, mesófilos e viscosidade. Os resultados mostraram que após 10 dias, a carbonatação em pH 5,8 inibiu a multiplicação de todos os microrganismos pesquisados independente da temperatura de armazenamento. A viscosidade não foi alterada logo após a carbonatação, mas durante a estocagem refrigerada houve elevação nos valores desta propriedade. Os modelos de superfície de resposta foram adequados para predizer a contagem de mesófilos e psicrotróficos e medida da viscosidade, pois a falta de ajuste não foi significativa e o coeficiente de determinação (R2) foi maior que 0,95.

A desidratação osmótica é usada para a remoção da água, de frutas imersas em solução aquosa. A qualidade da desidratação osmótica depende de diferentes fatores como: concentração, agente desidratante, temperatura, tempo de imersão, natureza das frutas e a área de superfície exposta à troca osmótica. A parede celular e o tipo de açúcar utilizado como agente osmótico podem influenciar no fenômeno de transferência de massa. A eficiência do processo de desidratação osmótica pode ser quantificada pelos valores de perda de peso e incorporação de sólidos. As mangas foram cortadas em cubos de 1cm de lado e levadas para os tratamentos com 50% sacarose (SAC), 50% sorbitol (SOR) e 50% estévia comercial (STV) acrescido de 1% de cloreto de cálcio e o pH corrigido em 4,0 com o uso de ácido cítrico, por duas horas a 50ºC. A proporção fruta:solução desidratante utilizada em todos os tratamentos foi de 1:3 em massa. O tratamento utilizando solução composta com estévia não se mostrou eficiente por causa do baixo ganho de sólidos e reduzida perda de água. A maior perda de água e uma maior perda de peso da manga durante a desidratação osmótica foram observadas para o tratamento com sorbitol, enquanto o maior ganho de sólidos foi obtido no tratamento com sacarose.The osmotic dehydration is used for water removal from immersed fruits in watery solution. The quality of the osmotic dehydration depends on different factors as concentration, dehydrating agent, temperature, time of immersion, nature of fruits and the surface displayed to the osmotic exchange. The cellular wall and the type of used sugar as osmotic agent can influence in the phenomenon of mass transference. The efficiency of the process of osmotic dehydration can be quantified by the values of loss of weight and solid incorporation. The mangoes had been cut in cubes of 1cm of side and taken for the treatments with 50% sucrose (SAC), 50% sorbitol (SOR) and 50% commercial estévia (STV) increased of 1% of calcium chloride and pH corrected in 4,0 with the acid use of citric, for two hours in 50ºC. The ratio fruit:solution used in all the treatments was of 1:3. The treatment using composed solution with estévia did not show to be efficient due to the low solid profit and reduced loss of water A bigger loss of water and a bigger loss of weight of the mango during the osmotic dehydration had been observed for the treatment with sorbitol, while the biggest solid profit was gotten in the treatment with sucrose.

As doenças transmitidas por alimentos (DTAs) são causadas por agentes biológicos, químicos ou físicos, os quais penetram no organismo humano pela ingestão de água ou alimentos contaminados. Este trabalho tem como objetivo a realização de um levantamento dos dados disponíveis sobre surtos de origem alimentar ocorridos no Paraná, no período de 1978 a 2000. O perfil epidemiológico das doenças transmitidas por alimentos no Brasil ainda é pouco conhecido, somente alguns estados e/ou municípios dispõem de estatísticas e levantamentos reais sobre os agentes etiológicos mais comuns, alimentos mais freqüentemente envolvidos e fatores contribuintes. Além disso, doenças transmitidas por alimentos nem sempre são oficialmente notificadas. No Paraná, dados obtidos oficialmente e disponíveis de surtos de DTAs apontam como agentes etiológicos mais freqüentes os de origem bacteriana, destacando-se Staphylococcus aureus e Salmonella sp. Verifica-se que os alimentos mais freqüentemente associados aos surtos são de origem animal, sendo os domicílios os locais de ocorrência de maior incidência. O número de surtos de DTAs cresce a cada ano e grande parte dos consumidores desconhece os requisitos necessários para uma correta manipulação de alimentos, incluindo o armazenamento (locais, temperatura, tempo de armazenamento) e, principalmente os perigos que podem estar associados aos alimentos contaminados. Os gastos destinados ao tratamento das DTAs foram quantificados a partir de dados do Sistema Único de Saúde (SUS) e do Hospital de Clínicas/UFPR de Curitiba, mostrando-se elevados e reafirmando que a área de segurança alimentar necessita maior atenção.The foodborne diseases are caused by biological, chemical or physical agents. The aim of this work was the accomplishment of a research of the available data on outbreaks of foodborne diseases happened in State of Paraná, in the period from 1978 to 2000. Only little information exists on the epidemic profile of the foodborne diseases in Brazil. Besides, foodborne diseases are not always officially notified. In State of Paraná, official and available data of foodborne diseases outbreaks showed bacterial infections as more frequent etiological agents, standing out Staphylococcus aureus and Salmonella sp. It was verified that the more frequently foods associates to the outbreaks are of animal origin, being the homes the places of occurrence of larger incidence. The number of foodborne outbreaks grows every year and the consumers' great part ignores the necessary requirements for a correct food handling, including the storage and mainly, the dangers that can be associated to the contaminated foods. The patient-related costs were quantified starting from data of the Sistema Único de Saúde (SUS) and of the Hospital de Clínicas/UFPR from Curitiba, being shown high and reaffirming that food safety's area needs more attention.

O cultivo do araçá-pêra, (Psidium acutangulum D. C.), fruto nativo da região Amazônica, tem despertado interesse de pesquisadores do sul do Brasil, pela possibilidade de representar uma nova oportunidade de sustento para os habitantes do litoral paranaense. O fruto apresenta boa proporção de polpa e suculência (rendimento em polpa 75,67%); porém, é excessivamente ácido para o consumo "in natura" (pH 2,77 e acidez livre 2,67%), tem aroma agradável e casca fina e amarga, sendo resistente ao corte. Possui valores de vitamina C de 60,98 mg/100g e fibra dietética de 9,6%. Objetivou-se com o presente trabalho desenvolver uma tecnologia e uma formulação para a fabricação de doce em massa do araçá pêra, que fosse simples e de fácil aplicação pelo pequeno produtor da região. Três formulações foram desenvolvidas com diferentes graus de redução da acidez do fruto. Na formulação A, foi utilizado um fruto neutro (chuchu 7%) para essa finalidade, nas formulações B e C, a redução da acidez deu-se pela adição de citrato de sódio nas proporções de 65% e 40% p/p da acidez livre do fruto, respectivamente. No intuito de diminuir o tempo de cozimento da massa, foi acrescentada pectina cítrica comercial (1,5%) às formulações B e C, não necessitando de sua adição na formulação A. O rendimento dos doces foi de 77,3% após cozimento da massa por 5 minutos em temperatura constante. Os doces apresentaram valores de pH / acidez de: (A): 3,1/1, 16, (B) 3,57/1,62 e (C) 3,36/1,70. Os doces foram submetidos às análises físico-química, microbiológica e sensorial, mostrando bom potencial para industrialização, com tecnologia facilmente aplicável pelo pequeno produtor.Araça Pera (Psidium acutangulum D.C., Myrtaceae) is a native plant from the Amazon region. The fruit is very pulpy (yields 75.67% after peeling and seedling), has a delicate, pleasant flavor, a peel like fine leather, which has to be taken off for it is bitter. It presents excessive acid content to be pleasant when eaten raw (pH 2.77; free acidity 2.67% citric acid), has a good amount of vitamin C (60.98 mg/100g), dietary fiber (9.6%), The objective of this study was to develop a formulation and technique for fruit processing by small producers in the region. Three formulations were tested using techniques of sensory analysis; in two formulations, the excess of acid was buffered with sodium citrate, equivalent to 65% (Formulation B) and 40% (Formulation C) of the amount of free acid present in the fruit, and commercial pectin (1.5%) was added to speed the cooking process. For formulation A, a fruit very common in the region and relatively inexpensive (chayote -7% of total ingredients) was chosen to buffer the acidity, and no pectin was needed. The ingredients simmered for 5 minute after temperature stabilized, and were poured into sterilized bottles, yielding 77.3% of jam, with a pH and free acidity of A-3.1/ 1.16; B-3.57/1.62; C-3.36/1.70. Physico-chemical, microbiological and sensorial analyses were performed showing good performance of the jams, easily reproducible by small producers.

A alface Crespa (Lactuca sativa L.)foi minimamente processada, tendo suas folhas destacadas e higienizadas, embalada em sacos plásticos de polietileno com modificação ativa da atmosfera dentro do pacote. Duas atmosferas foram aplicadas, variando-se o nível de CO2 em 10 e 15%, reduzindo nos dois casos o O2 a 5%. Após o acondicionamento, a alface foi imediatamente refrigerada. Comparou-se a qualidade da alface com e sem atmosfera modificada durante o armazenamento refrigerado. Monitoraram-se a variação da concentração de O2 e CO2 no interior das embalagens e a vida-útil da alface pela análise sensorial e microbiológica e a variação de sólidos solúveis. A influência da atmosfera modificada no crescimento de microrganismos e na variação de sólidos solúveis não foi relevante. Entretanto, essa tecnologia reduziu as taxas de respiração e, conseqüentemente, minimizou as perdas de qualidade sensorial da alface durante todo o armazenamento. A vida-útil da alface em atmosfera modificada foi estendida em até cinco dias além daquela alcançada pela alface acondicionada em atmosfera normal.The crisp head lettuce (Lactuca sativa L.)was minimally processed, with the leaves being detached and cleaned, packaged in plastic bags made of polyethylene with modified atmosphere inside the bag. Two different atmospheres were applied: 10 and 15% of CO2, with the O2 level being reduced in both cases to 5%. After the packing, the lettuce was immediately refrigerated. The product quality with and without modified atmosphere was compared during the storage time. It was accompanied the changes in O2 and CO2 concentration inside the packaging and the product shelf life, through sensorial and microbiological analysis, and soluble solids variation. The influence of modified atmosphere in microorganisms grown and in soluble solids variation was not relevant. However this technology reduced the lettuce respiration rates and the quality sensorial loss during storage. The shelf life of lettuce in modified atmosphere was extended in five days in comparison with the ones packaged in normal atmosphere.

O presente trabalho consistiu na caracterização da polpa de carne de carpa prateada (Hypophthalmichthys molitrix) e dos produtos reestruturados: "fishburger" e "nugget". A partir da polpa, elaborou-se o "fishburger" e o "nugget" empanado, como forma de aproveitamento desse tipo de matéria-prima. Os produtos elaborados foram avaliados sob os aspectos físico-químicos, microbiológicos e sensoriais. O teste de aceitação do "fishburger" e "nugget" mostrou que dos 36 provadores proporcionou uma média de 7,7 que corresponde a 94,4% de aceitabilidade para o "fishburger" e a média de 6,9 que corresponde a 72,3% de aceitabilidade para o "nugget". PALAVRAS-CHAVE: Carpa prateada; hambúrguer de peixe; "nugget" empanado.

Abstract Yacon is a tuberous root from the Andean region being increasingly grown across the world due to the low caloric values of their roots and the functional properties of extractions of its leaves. However, there is still a gap in the knowledge of how the plant develops, and if physical and chemical changes are noticed regarding maturity. The subject of this work was to investigate the dynamics of a group of parameters and to establish correlations across them. To achieve this goal, leaves collected from three different parts of the plant in three months were assessed regarding size (plant height and leaf area), color and the presence of sesquiterpene lactones. Different methods of extraction were also studied and the total phenolic content was analyzed. The analysis of the results revealed different patterns in the quantity, size and leaf distribution according to the age of the plant. From three different methods of extraction studied, decoction seems to be the most appropriate one to obtain phenolic compounds with greater yield and safety. Besides, the greenness of yacon leaves showed a linear correlation to the total phenolic content, being a simple and promising estimator of the corresponding bioactive group. Sesquiterpene lactones were identified in all extracts, indicating the ease of their extractability even in simple procedures of tea-making.