RCAAP Repository

Resumo Este estudo trata dos táxons de Dryopteridaceae encontrados nas formações ferríferas da Serra dos Carajás, estado do Pará, com descrições, ilustrações, distribuição geográfica e comentários. Na área estudada foram registrados quatro gêneros e quatro espécies: Ctenitis nigrovenia, Dryopteris huberi, Elaphoglossum glabellum e Polybotrya sorbifolia.

Resumo Este estudo trata dos táxons de Lycopodiaceae encontrados nas formações ferríferas da Serra dos Carajás, estado do Pará, com descrições, ilustrações, distribuição geográfica e comentários. Na área estudada foi registrada apenas Palhinhaea cernua.

Resumo Este estudo trata dos táxons de Lygodiaceae encontrados nas formações ferríferas da Serra dos Carajás, estado do Pará, com descrições, ilustrações, distribuição geográfica e comentários. Na área estudada foi registrada apenas Lygodium venustum.

Abstract There are various known extraction methods that can be applied to the quantification of phenolic compounds, and thus it is up to the researcher to perfect the process that best applies to the sample in question. Different extraction solvents (liquid-liquid extraction) were compared in order to assess their effectiveness for the analysis of total phenols in jambolan ( Syzygium cumini Lamark) pulp extract using the conventional Folin-Ciocalteau methodology. Three CCRDs (Central Composite Rotational Designs) were carried out to evaluate the factors influencing the extraction process conditions. The variables studied were the solvent concentration (ethanol and methanol, diluted in water) and the mixing time in the compound extraction process. Of the conditions studied, it was shown that a 60% ethanol in water extraction solvent with a mixing time of 10 minutes, in addition to extracting a greater concentration of phenolic compounds, showed the greatest cost benefit advantage, since ethanol is cheaper and less toxic than methanol.

Abstract The objective of this work was to evaluate the efficacy of ethyl acetate as a solvent in the extraction of macauba kernel oil (MKO) using ultrasonic-assisted extraction (UAE). It was shown that more MKO oil could be extracted with the use of larger amounts of solvent, higher temperatures and longer extraction times. Thus the maximum oil yield (40.61%) was obtained by UAE at 60 °C for 45 min, using a solvent to kernel ratio of 12 (mL g-1), obtaining a higher yield than that obtained with n-hexane under the same experimental conditions. UAE was favorable for this oil extraction (p < 0.05), presenting a yield close to that reported for classical extraction but with a shorter extraction time and smaller solvent volume. Lauric acid corresponded to ~44% of the MKO composition. The oils presented low free fatty acid contents (<0.80% wt), and the phytosterols, campesterol and β-sitosterol, were identified in the MKO with higher levels in the oil obtained by UAE.

Resumo O acuri é uma fruta pouco explorada industrialmente, mas com grandes perspectivas e possibilidades de uso. Para tanto, torna-se necessário reduzir o seu teor de água, aumentando então a sua vida útil, o que possibilitará sua utilização em mercados distantes dos locais de produção. Nesse sentido, objetivou-se secar fatias de acuri, com espessura de aproximadamente 4,07 mm, nas temperaturas de 60, 70, 80 e 90 °C, ajustar diferentes modelos matemáticos aos dados experimentais e determinar os coeficientes de difusão, a energia de ativação e as propriedades termodinâmicas. Observou-se que o aumento de temperatura de 30°C reduziu em 36% o tempo total de processo, sendo obtidas taxas de secagem máximas de 1,22; 1,88; 2,16, e 2,45 kg de água kg de matéria seca min-1 nas temperaturas de 60, 70, 80 e 90 °C, respectivamente. Dentre os modelos matemáticos testados, o modelo logarítmico apresentou os melhores parâmetros de ajustes aos dados experimentais e foi selecionado como o mais adequado para representar o fenômeno investigado. Os coeficientes de difusão efetivos aumentaram com o incremento de temperatura, apresentando-se na ordem de 10-10 m2 s-1 , e sua dependência com a temperatura foi descrita pela Equação de Arrhenius, que apresentou energia de ativação de 17,66 kJ mol-1 . Os valores de entalpia e entropia reduziram com a elevação da temperatura de secagem, enquanto que a energia livre de Gibbs foi ampliada na faixa de temperatura avaliada.

Resumo O único tratamento para a doença celíaca é uma dieta isenta de glúten por toda a vida, o que torna necessária a oferta de novos produtos para esse público. O sorgo e o milho são cereais que, além de apresentarem propriedades funcionais, são possíveis de serem inseridos como ingredientes em dietas sem glúten, por não possuírem, em sua composição, as proteínas formadoras de glúten. Assim, este estudo objetivou elaborar massas secas utilizando farinha de sorgo e de milho, e avaliar algumas características químicas e de cozimento, assim como a aceitabilidade sensorial dos produtos formulados, frente a um painel de indivíduos celíacos e não celíacos. As amostras incluíram uma massa elaborada unicamente com farinha de sorgo, outra com 50% de farinha de sorgo e 50% de farinha de milho, e uma terceira, à base unicamente de farinha de milho. O produto elaborado com 100% de farinha de sorgo apresentou conteúdos significativamente mais altos de proteína, lipídeos, cinzas, fibra e fenólicos totais, em comparação com os demais. A perda de sólidos dos produtos variou de 5,04% a 10,54%, parâmetro de qualidade considerado adequado para macarrão. Após cozimento, as três massas absorveram mais de duas vezes os seus pesos em água (108,1 a 143,1%). Embora o público composto por pessoas não celíacas tenha preferido a massa à base de farinha de milho, aquela elaborada unicamente com farinha de sorgo apresentou aceitabilidade satisfatória entre os provadores portadores da doença celíaca, o que demonstra o potencial deste ingrediente em macarrões destinados a este público.

Abstract The aim of this work was to improve the classification of green asparagus in an agro-export company by way of a Computer Vision System (CVS). Thus, an image analysis application was developed in the MATLAB® environment to classify green asparagus according to the absence of white spots and the width of the product. The CVS performance was compared with a manual classification using the error in the classification as the quality indicator; the yield from the raw material (%) and line productivity (kg/h) as the production indicators; and the net present value (USD) and internal rate of return (%) as the economic indicators. The CVS classified the green asparagus with 2% error; improved the yield from the raw material from 43% to 45%, and line productivity from 5 to 10 kg/h; and increased the net present value by 102,609.00 USD, yielding an Internal Rate of Return of 156.3%, much higher than the Opportunity Cost of the Capital (8.6%). Hence the classification of green asparagus by a CVS is an efficient and profitable alternative to manual classification.

Abstract Recently, in Brazil, coloured-tegument soybean cultivars have been developed, such as those with brown and black teguments. Soybeans with black teguments have been widely used for decades due to their health benefits and their use in oriental folk medicine as a result of the presence of phytochemicals. They have been recognized as health-promoting functional food ingredients due to their antioxidant activity, and are also known to have anti-cancer, hypoglycaemic and anti-inflammatory effects and have been used in the treatment of various circulatory disorders. This study aimed to determine the proximate composition, fatty acid levels and lipoxygenase activity of soybean lineages with different tegument colours intended for human consumption. The lineage MGBR10-16601 which has a yellow tegument, presented the highest protein and lowest fat contents, with values of 37.6 g 100 g-1 and 18.3 g 100 g-1, respectively. The lineage MGBR10-16201, which also has a yellow tegument, was identified as free of lipoxygenase isoenzymes. The unsaturated fatty acid levels ranged from 18.48 to 31.37 mg g-1 and from 47.36 to 58.31 mg g-1 for oleic and linoleic acids, respectively. The lineage BRN07-50543, which has a black tegument, presented high total isoflavone levels (546 mg 100 g-1), with an oleic acid level above and linoleic acid level below the standards established by the Codex Alimentarius for soybean oil, with values of 31.37 mg g-1 and 47.36 mg g-1, respectively. The cultivar BRSMG 790A, which has a yellow tegument, presented the lowest isoflavone level (171.4 mg 100 g-1). All the genetic materials examined presented crude protein, fat, dietary fibre and ash levels within the commercial parameters established for soybeans.

Abstract Chayote (Sechium edule) is a perennial climbing plant, belonging to the Cucurbitaceae family and is neglected or underutilized as a food or as a raw material in the food industry because of its bland taste. This bland taste can be overcome by blending with a suitable substrate such as sugarcane juice along with natural flavouring. However, this blending represents a preservation problem for the spiced juice, since both chayote juice and sugarcane juice are prone to microbial attack. Therefore, an attempt was made in the present study to preserve the spiced chayote juice by employing different hurdles i.e. pasteurization temperature (70 °C and 80 °C) and pasteurization time (10 and 20 min) followed by the addition of different concentrations of potassium metabisulphite (KMS) (200, 300 and 400 ppm). The samples so prepared were filled into glass bottles and stored under refrigeration for forty-five days. As the storage period proceeded there were significant decreases in pH, total protein content, total phenolic compounds, antioxidant activity, reducing power, metal chelation, tannin content, ascorbic acid content and overall acceptability, whereas there were significant increases in TSS (total soluble solids), titratable acidity, reducing sugars, total sugar, TPC (total plate count) and MIC (minimum inhibitory concentration). A cluster analysis of the data revealed that the pasteurization temperature exerted the most significant effect on the physicochemical and sensory characteristics of the spiced chayote juice as compared to the pasteurization time and KMS concentration, which failed to fall into the separate and respective clusters. In a nutshell, it was concluded that spiced chayote juice can be successfully preserved using hurdle technology (pasteurizing at 70 °C for 10 min followed by the addition of 400ppm KMS).

Abstract The enzyme-assisted extraction of bioactive compounds from plants has been studied as an alternative green technology and the carbohydrases have been candidates to improve the extraction process of numerous such compounds from plants. Polyphenols are secondary plant metabolites, generally involved in the defense against different types of stress and yerba mate (Ilex paraguariensis A. St.-Hil., Aquifoliaceae) is a natural source of these antioxidant compounds. The aim of this work was to evaluate the enzyme-assisted extraction of polyphenols from green yerba mate employing response surface methodology (RSM), in order to determine the best extraction conditions. The independent variables were temperature (33.2 to 66.8 °C), enzyme concentration (0 to 336 FGBU/100g), reaction time (19 to 221 minutes) and pH (2.82 to 6.18). The use of carbohydrases increased the extraction of polyphenols from about 38.67% to 52.08%. The present results showed that all the independent variables were significant at the linear level and that temperature and pH were not significant at the quadratic level. The interactions of temperature and pH; enzyme and reaction time; and enzyme and pH were significant. The regression model presented a determination coefficient (R2) close to 0.85 and a fitted value close to 0.45. Considering the results of this study and their industrial viability, the best conditions for the extraction of polyphenols from green yerba mate are a temperature of 50.0 °C, enzyme concentration of 168 FGB/100 g, reaction time of 120 minutes and pH value of 4.50. This study was the first RSM-based report of the optimization of the enzyme-assisted extraction of total phenolic compounds from green yerba mate.

Abstract The food provided in nursery schools should meet the sanitary and nutritional requirements needed to promote a child's intellectual and physical health. Therefore, training of the School Nutrition Technicians (SNT) in good food handling practices is essential to ensure the safety of the foods prepared. This study was aimed at evaluating the microbiological quality of lettuce salads consumed by children in public nursery schools in the municipality of Cuiabá, Mato Grosso, Brazil. The lettuce salad samples were collected in two distinct phases: before and after training of the SNTs in good food handling practices by the nutritionists of the school meals program of the municipality of Cuiabá, according to the school calendar routine. Thirty fresh (in natura) lettuce samples that had not been sanitized (representing samples obtained from the supplier) were collected for the detection of Salmonella spp. and 240 prepared lettuce salad samples (salads ready for consumption), for the detection of Salmonella spp. and the heat-tolerant coliform count. The genus Salmonella was not detected in either of the phases of the study. However, prior to training, 54% of the lettuce salad batches were contaminated with heat-tolerant coliforms, but after training 100% of the batches were considered to be in satisfactory sanitary conditions. In conclusion, offering training courses on good food handling practices to food handlers in school meals units was capable of reducing contamination.

Abstract Pseudomonas aeruginosa is an opportunistic pathogen capable of forming biofilms of great relevance to medical microbiology and the food industry. Essential oil (EOs) constituents have been researched as new strategies for the control of biofilms. In the present study cinnamaldehyde was shown to be an effective EO against the planktonic cells of P. aeruginosa strains (p < 0.05). Thus it was used to prepare sanitizing solutions, which were tested against P. aeruginosa biofilms formed on stainless steel surfaces. Cinnamaldehyde showed antibacterial activity against sessile P. aeruginosa cells (p < 0.05). A 100% (5.87 log-reduction) elimination of viable bacterial cells was obtained after treatment with a 6xMIC (0.06% Minimal Inhibitory Concentration) solution for the strain ATCC 9027. Sanitizing cinnamaldehyde solutions can be used as new alternatives to control such microbial sessile communities in food industries.

Abstract Emulsifiers are responsible for forming a dough that contributes to the retention of gluten in alveoli, the gas produced by the yeast, thus increasing the volume and softness of the bread. There are indications that hydrocolloids, such as taro mucilage (Colocasia esculenta), can present similar characteristics to emulsifiers. The presence of arabinose and galactose in the taro mucilage is responsible for the formation of a complex with proteins, called Proteoglycan arabinogalactan, that could present substantial emulsifying power, consequently favouring gas retention in the alveoli. Thus, the quantity, distribution and size of the alveoli must be analysed for the effective quality control of the breadmaking process, and this is therefore recommended. Conventional statistical methods are already used regularly in analyses of these variables, although spatial statistics have not been used for this purpose. In this paper, the authors defend the application of univariate point processes that have not been applied to the analysis of the spatial distribution of the alveoli in French bread made with taro mucilage. The results showed that these methods made it possible to characterize the spatial distribution of alveoli in French bread, demonstrating that the use of taro mucilage provided a good alveolar distribution in French type bread.

Abstract Appropriate storage packaging is an important aspect to minimize physiological deterioration and enhance the shelf-life of minimally processed products. Thus, the goal of this study was to evaluate the physiological and biochemical changes associated with the quality loss of minimally processed yam, maintained in two different packages at 5 ± 2 °C. The yam roots were selected, washed and conserved at 8 ± 2 °C for 24 hours. They were then peeled and cut into slices about 3 cm thick and minimally processed. Approximately 300 g of minimally processed yam roots were packed in polypropylene (PP, 4 μm thick) and multilayer nylon (NY, 15 μm thick) 15 cm wide x 20 cm long bags, which were stored at 5 ± 2 °C for 14 days. The minimally processed yam conserved in PP packaging presented fluorescence on the surface of the segments, characteristic symptoms of Pseudomonas spp., and showed higher peroxidase and catalase activities. The nylon packaging was more efficient in reducing oxidative damage and also inhibited polyphenol oxidase activity and decreased the accumulation of soluble proteins, resulting in decreased deterioration during storage. Thus, the quality of the minimally processed yam maintained in NY packaging was conserved for 14 days at 5 ± 2 °C.

Resumo A lagosta é uma espécie marinha de grande importância em muitos países. As mudanças bioquímicas e microbiológicas que ocorrem após a captura determinam sua qualidade e vida útil. Objetivou-se, neste trabalho, estudar o efeito da temperatura de armazenamento sob congelamento (-30 ºC, -80 ºC e -150 ºC), do tipo de embalagem (polietileno de baixa densidade – PEBD, com vácuo e sem vácuo) e do tempo de armazenamento (0, 60, 120, 180, 240, 300 e 360 dias) sobre as características físicas de cor (luminosidade, intensidade de vermelho e amarelo) e químicas (proteínas e lipídeos) da lagosta. Durante o armazenamento, os parâmetros físicos luminosidade e intensidade de vermelho aumentaram, a intensidade de amarelo diminuiu, os teores de proteína diminuíram, porém para lipídeos não houve diferença significativa. Pode-se concluir que as temperaturas de armazenamento estudadas e a presença ou ausência de vácuo nas embalagensforam eficientes na manutenção das características físicas e químicas das caudas das lagostas armazenadas.

Abstract A commercial H2O2 solution (35%, v/v) was evaluated as a clarifying agent for raw, type VHP (very high polarization) sugar syrup, using an experimental design applying artificial neural networks (ANN). Fifteen experimental runs were carried out and the samples were taken at the following time intervals: 0, 5, 10, 15, 20, 25, 30, 40, 50, 60, 75 and 90 min. The treatments were carried out using an experimental design consisting of three variables: H2O2 (X1: 0; 202.4; 500; 797.6 and 1.000 mg L-1); pH (X2: 3.32, 5, 7.5, 10 and 11.68) and temperature (X3: 16.4, 30, 50, 70 and 83.6°C). The theoretical and measured values fitted the analysis by artificial neural networks (ANN) well. A reduction in colour (ICUMSA method) was observed between 60 and 75 min, except for treatments # 11 (pH= 11.68; 50°C and 500 mgH2O2 L-1), # 13 (pH=7.5; 83.6°C and 500 mgH2O2 L-1) and #15 (pH= 7.5; 50°C and 1.000 mgH2O2 L-1), which showed a colour reduction after 30 min. In the treatments at pH 3.32 or 11.68, temperature of 83.6°C and H2O2 dose of 1.000 mg L-1, an average sucrose degradation of 55% was observed. The best colour reduction result was obtained with treatment # 9 (pH 7.5, 50 °C and 500 mgH2O2 L-1), although sucrose degradation of 26% was observed.

Resumo O ácido polilático (PLA), o mais conhecido bioplástico com potencial para ser o substituto dos polímeros derivados do petróleo, é produzido pela polimerização do ácido lático. A aplicação do ácido lático para a produção de ácido polilático tem levado a um aumento substancial no seu consumo. Entretanto, o custo da matéria-prima representa um grande obstáculo na produção econômica de ácido lático para essa finalidade. Assim, vários materiais têm sido considerados como substratos alternativos, incluindo subprodutos de indústrias agrícolas, indústrias de alimentos e biomassas naturais. O presente trabalho avaliou o uso de resíduos da indústria de alimentos como suplemento nutricional do soro de leite para produção de ácido lático por cultura mista imobilizada de bactérias láticas (Lactobacillus acidophilus LA-5, Bifidobacterium BB-12 e Streptococcus thermophilus). Foram testadas três condições de pH (6,0; 6,5 e 7,0) e três condições de temperatura (30 °C, 35 °C e 40 °C) de fermentação. Também foram testados três níveis de suplementação do soro de leite com cada um dos resíduos: água de maceração de milho – AMM (0%, 5% e 10%); vinhaça (0%, 5% e 10%) e extrato de levedura (0%, 3% e 6%). Ao final da fermentação, observou-se que os tratamentos com temperatura de 40 °C e o pH inicial de 7,0 apresentaram teor de ácido lático 10% superior aos demais. Todos os resíduos foram efetivos em aumentar a produção de ácido lático quando suplementados no soro de leite. O extrato de levedura apresentou a maior concentração de ácido lático, com 0,0307 mol.L-1, resultado 20% superior ao da água de maceração de milho e vinhaça.

Abstract The present work aimed to evaluate the effect of the antifreeze protein on the microstructure and physicochemical properties of hidroponic strawberries, evaluating the titratable acidity, pH, colour and optical microscopy before freezing both in natura (IN) and impregnated with the protein (IP), and after thawing without the protein (TWP) and impregnated (TIP) with the antifreeze protein (AFP Type I from fish) by vacuum impregnation. After thawing, the treatment was also compared in terms of drip losses. The antifreeze protein impregnated strawberries showed no statistical differences with respect to the physicochemical properties, but the drip loss was statistically lower from the thawed strawberries treated with the antifreeze protein. The vacuum impregnated thawed strawberries showed less damage to the microstructure. The cells of the thawed samples with antifreeze protein conserved the structure of the reference samples of in natura strawberry.

Resumo A possibilidade de combinação de ingredientes alimentícios em cada refeição torna complexo o reconhecimento das características dos alimentos personalizados. A utilização de dispositivos com tecnologias da Internet of Things (IoT) consiste em uma alternativa para os clientes acessarem informações dos alimentos personalizados. Nesta pesquisa, foram identificados cinco principais atributos na composição desses dispositivos com objetivo de reconhecimento dos ingredientes em refeições customizadas: (A) portabilidade, (B) precisão, (C) personalização de dieta, (D) análise de qualidade do produto alimentício e (E) preço. Este estudo possui como objetivo identificar a combinação desses atributos que geram valor em um dispositivo de reconhecimento de características alimentares de alimentos customizados. Foi realizado um planejamento fatorial fracionado 25-1 para a apresentação dos atributos do dispositivo na forma de cenários, seguindo o método de análise conjunta baseada em escolha. Para a coleta de dados, foi realizada uma pesquisa com uma amostra de 303 respondentes. Ainda foram analisadas as variáveis moderadoras: gênero e presença de restrição alimentar. Os resultados obtidos apresentaram maior significância para os atributos: precisão de medida e análise de qualidade. Como contribuições, este estudo apresenta informações para o direcionamento de investimentos em pesquisa para elaboração de um dispositivo tecnológico com a finalidade de reconhecer características de um produto alimentício customizado em massa.