Abstract Rosemary (Rosmarinus officinalis) is known for their sensory characteristics and antioxidant properties, mainly due to the presence of several phenolic compounds. The aim of this work, was determine the antioxidant activity and apply the Rosemary lyophilized extract (RLE) in chicken burger, for assess their ability to reduce the lipid oxidation. Total antioxidant capacity and phenolic compounds profile were analyzed by colorimetric tests and liquid chromatography analysis, respectively. Thiobarbituric acid reactive substances assay was used to evaluate the ability of the RLE to prevent lipid peroxidation in chicken burger stored at 4 °C. Three treatments of chicken burgers were prepared (T1 – control, without addition of synthetic antioxidant BHT: butylated hydroxytoluene or RLE), T2 – with addition of BHT, and T3 – experimental, containing RLE). The high contents of total phenolic compounds (40.91 mg GAE g-1: Gallic Acid Equivalent) and total flavonoids (24.26 mg QE g-1: Quercetin Equivalents) were found in RLE. Rutin was the major phenolic compound identified in the RLE. The RLE showed strong antioxidant capacity and inhibited 48.29% of lipid oxidation (21 days of storage) in comparison to the control (T1), with low production of malonaldehyde, which has potential to be used in chicken burgers.

Ácidos graxos tem grande importância metabólica e estrutural. Avaliação da composição de ácidos graxos em pimentas é ainda incompleta. Polpas e sementes de seis variedades de pimentas do gênero Capsicum foram avaliadas, neste trabalho, em relação a sua composição de ácidos graxos. Foram identificados 25 ácidos graxos diferentes nas amostras, incluindo alguns com número ímpar de átomos de carbono. Os ácidos graxos mais abundantes foram palmítico (16:0), oleico (18:1n-9) e linoleico (18:2n-6). As relações poli-insaturados:saturados foram elevadas para todas as amostras, em razão das elevadas quantidades de ácidos poli-insaturados, principalmente o ácido linoleico. Nas polpas as relações de omega-6/omega-3 variaram de 1,28 a 4,33, e foram avaliadas como relativamente adequadas, tendo em vista que, na dieta humana, relações entre 0,25 e 1,0 são consideradas altamente adequadas. Nas sementes, os níveis de n-3 foram muito mais baixos do que os níveis de n-6, que foram bem elevados, resultando em baixas proporções de omega-6/omega-3, variando entre 74,2-279,6. Análise de componentes principais (ACP) explicou 93,49% da variância total dos dados. Considerando as relações poli-insaturados: saturados e omega-6/omega-3, nossos dados sugerem que entre as pimentas do gênero Capsicum avaliadas, neste trabalho, o pimentão e a pimenta habanero laranja apresentaram as melhores características nutricionais em relação à composição de ácidos graxos.

Fatty acids have a great metabolic and structural importance. Evaluation of fatty acid composition of peppers is still incomplete. Pulps and seeds from six varieties of the genus Capsicum were evaluated in this work with respect to their contents in fatty acids. A total of 25 different fatty acids, including some with odd number of carbons were identified in the samples. The most abundant fatty acids were palmitic (16:0), oleic (18:1n-9) and linoleic (18:2n-6) acids. The polyunsaturated:saturated fatty acid (PUFA/SFA) ratios for all peppers were high due to the elevated amounts of polyunsaturated acids, particularly linoleic acid. In the pulps, the omega-6/omega-3 ratios ranging from 1.28 to 4.33, were relatively adequate if one considers that ratios between 0.25 and 1.0 in the human diet are regarded as highly appropriate. In the seeds, the levels of omega-3 were very low whereas the levels of omega-6 were high, leading to very inadequate omega-6/omega-3 ratios ranging from 74.2 to 279.6. Principal component analysis (PCA) explained 93.49% of the total variance of the data. Considering the PUFA/SFA ratio and omega-6/omega-3 ratio, our data suggest that, among the peppers of the genus Capsicum evaluated in this work, the bell pepper and orange habanero pepper present the best nutritional characteristics concerning fatty acid composition.

The objective of this work was (1) to develop a dehydrated pepper with 45% humidity, determining the drying curves for pepper, with and without osmotic pre-treatment and (2) to evaluate the influence of both drying and osmotic treatment on the content ascorbic acid (vitamin C) in fresh pepper and pepper with 45% humidity. The experiments were carried out using the peppers cut in half, with and without osmotic pre-treatment, followed by drying in an oven at 70 ºC. The results showed that the osmotic pretreatment did not influence the retention of ascorbic acid during the drying of pepper. The sensory analysis regarding the color, flavor, and texture attributes revealed that there was no difference in the acceptability.

Neste trabalho, o comportamento reológico de sistemas pécticos formulados com as pectinas extraídas das polpas de morango, amora-preta e framboesa foi investigado através de testes reológicos oscilatórios. Adicionalmente, as propriedades químicas dessas pectinas foram estudadas. Os sistemas pécticos das polpas de frutas vermelhas apresentaram um caráter de gel forte de acordo com os testes reológicos, sendo o gel de morango caracterizado como o mais forte. Os testes reológicos foram confirmados pelo experimento de Cox-Merz, grau de esterificação e peso molecular médio. O ácido galacturônico está diretamente relacionado com a formação da rede de pectina. Além disso, a diferença entre a força dos três géis pécticos pode ser atribuída aos valores do grau de esterificação e peso molecular médio desses biopolímeros. As pectinas extraídas das frutas vermelhas estudadas neste trabalho podem ser classificadas como pectinas de alta metoxilação, apresentado o grau de esterificação maior que 50%. Os três géis pécticos apresentaram uma boa estabilidade ao aumento da temperatura e ao tempo de cisalhamento oscilatório constante.

In this work, the rheological behavior of pectic systems formulated with pectins extracted from strawberry, blackberry, and raspberry pulps was investigated by means of oscillatory rheological tests. In addition, the chemical properties of these pectins were studied. The pectic systems from those red fruit pulps showed a strong gel character according to the rheological tests showing that the strawberry pectin presented the strongest gel character, which was confirmed by the Cox-Merz experiment, degree of esterification, and average molecular weight data. The galacturonic acid is directly related to the formation of the pectin network. Besides, the difference between the strength of the three pectic gels can be attributed to the esterification degree values and the average molecular weight of these biopolymers. The pectins extracted from the red fruits studied in this work can be classified as high methoxy pectins with a degree of esterification higher than 50%. The pectic gels exhibit good stability with an increase in temperature and in the shear-oscillatory constant time.

No presente trabalho foi utilizado amido obtido de banana verde (Musa cavendishii) e amido de milho (Zea mays) comercial, com o objetivo de comparar a morfologia dos grânulos e o comportamento reológico dos géis. As imagens da morfologia dos grânulos foram obtidas por microscopia eletrônica de varredura. Os grânulos de amido da banana apresentaram forma oval e elipsoidal com diâmetros irregulares, todavia, os grânulos do amido de milho mostraram forma poliédrica e diferentes tamanhos. As análises reológicas dos géis das soluções de amido mostraram caráter não-newtoniano, pseudoplástico. O modelo de Herschel-Bulkley foi o que melhor representou comportamento reológico dos géis. O gel de amido de banana verde obteve maiores valores de tensão de cisalhamento e viscosidade aparente quando comparada ao gel de amido de milho. Ocorreu um decréscimo progressivo na tensão de cisalhamento e na viscosidade com a adição de cloreto de sódio e sacarose aos géis.

In this work, it was used starch obtained from green banana (Musa cavendishii) and commercial corn (Zea mays) starch in order to compare the granule morphology and the rheological behavior of these gel-starches. Images of starch granules morphology were obtained from scanning electron microscope (SEM). The banana starch granules presented an oval and ellipsoidal shape with irregular diameters. Neverthless, the granules of corn starch showed a poliedric shape, with different sizes. The rheological behavior of gel starch solutions showed a non-newtonian character with a pseudoplastic behavior. Herschel-Bulkley model gave a good description on the rheological behavior of the gel starch. Banana gel-starch solutions showed higher values of shear stress and apparent viscosity when compared with corn gel-starch solutions. A progressive decrease in shear stress and viscosity occurred with the addition of sodium chloride and sucrose.

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 (n<1) e uma diminuição na viscosidade aparente com o aumento da taxa de deformação e temperatura, sendo que a viscosidade aparente da polpa de manga centrifugada tendeu a ficar constante a partir 200s-1.

The 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<1) and a decrease in apparent viscosity with an increase in shear rate and temperature, whereas the apparent viscosity of the centrifuged mango pulp had a tendency to stay steady up to 200s-1.

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.