Sidinéa Cordeiro de Freitas

Chemical characterization and evaluation of antioxidant properties of Açaí fruits (Euterpe oleraceae Mart.) during ripening

Consumption of açaí fruits has been linked to positive health effects due to its phenolic content and nutritive value. The objective of this study was to characterize açaí fruits chemically and to determine the antioxidant capacity at three different maturity stages. With the exception of fat, amounts of macronutrients, minerals and titratable acids decreased during the ripening process. The same trend was observed for most of the phenolic constituents identified by HPLC-ESI-MS/MS. A consistent decline was shown for flavones and hydroxycinnamic acids. The concentration of the anthocyanins increased in the course of ripening. In accordance with the total amount of the identified phenolic compounds, the antioxidant capacity, measured by TEAC and TOSC, also decreased. However, the contribution of the main phenolic compounds to the overall antioxidant capacity evaluated by TOSC was estimated to be low.

UTILIZATION OF AGROINDUSTRIAL RESIDUES FOR LIPASE PRODUCTION BY SOLID-STATE FERMENTATION

The aim of this work was to produce lipases by solid-state fermentation (SSF) using, as substrate, agroindustrial residue supplemented with by-products from corn oil refining process or olive oil. For a group of ten fungi strains selected in the first steps, the lipase activity obtained by SSF varied from 7.7 to 58.6 U/g of dry substrate (gds). Among the evaluated strains, the Aspergillus niger mutant 11T53A14 was selected by presenting the best enzymatic production. For the fermentation tests, two substrates were also investigated: wheat bran and corn cob, both supplemented with olive oil. The best results were obtained with wheat bran. Additionally, three industrial by-products from corn oil refining (soapstock, stearin and fatty acids) were evaluated as substitutes to the olive oil in the function of lipases production inducer. Among them, soapstock and stearin were the best inducers, whereas fatty acids presented an inhibitor effect. The highest lipase activities using soapstock, stearin and fatty acids were 62.7 U/gds, 37.7 U/gds and 4.1 U/gds, respectively.

Iron and zinc retention in common beans ( Phaseolus vulgaris L. ) after home cooking

Background According to the World Health Organization (WHO), iron, iodine, and Vitamin A deficiencies are the most common forms of malnutrition, leading to severe public health consequences. The importance of iron and zinc in human nutrition and the number of children found to be deficient in these nutrients make further studies on retention in cooked grains and cooked bean broth important. Objectives This work aimed to evaluate iron and zinc retention in six common bean (Phaseolus vulgaris L.) cultivars under the following conditions: raw beans, regular pot cooking, pressure cooking, with and without previous water soaking, and broth. Design Determination of iron and zinc content in the raw, cooked bean grains and broth samples was carried out by Inductively Coupled Plasma (ICP) Optical Emission Spectrometry (Spectro Analytical Instrument – Spectroflame P). All experiments and analyses were carried out in triplicate. Results Overall, regardless of the cooking method, with or without previous water soaking, the highest zinc concentration was found in the cooked bean grains. However, pressure cooking and previous water soaking diminished iron retention in the cooked grains, while increasing it in the bean broth. Conclusion The common bean was confirmed to be an excellent source of iron and zinc for human consumption, and it was suggested that beans should be consumed in a combined form, i.e. grain with bean broth.

Effects of cooking methods on the iron and zinc contents in cowpea ( Vigna unguiculata ) to combat nutritional deficiencies in Brazil

Background Because iron deficiency anemia is prevalent in developing countries, determining the levels of iron and zinc in beans, the second most consumed staple food in Brazil, is essential, especially for the low-income people who experience a deficiency of these minerals in their diet. Objectives This study aimed to evaluate the effect of cooking methods by measuring the iron and zinc contents in cowpea cultivars before and after soaking to determine the retention of these minerals. Methods The samples were cooked in both regular pans and pressure cookers with and without previous soaking. Mineral analyses were carried out by Spectrometry of Inductively Coupled Plasma (ICP). Results The results showed high contents of iron and zinc in raw samples as well as in cooked ones, with the use of regular pan resulting in greater percentage of iron retention and the use of pressure cooker ensuring higher retention of zinc. Conclusions The best retention of iron was found in the BRS Aracê cultivar prepared in a regular pan with previous soaking. This cultivar may be indicated for cultivation and human consumption. The best retention of zinc was found for the BRS Tumucumaque cultivar prepared in a pressure cooker without previous soaking.

Soy and Brazil nut beverage: processing, composition, sensory, and color evaluation.

Apesar do alto valor nutricional do extrato de soja, seu consumo nos paises do ocidente ainda e limitado principalmente devido as caracteristicas sensoriais desagradaveis resultantes do seu tradicional processo de obtencao. A castanha do Brasil (Bertholletia excelsa) apresenta sabor agradavel e e reconhecida por seu valor nutricional. Para promover a incorporacao da castanha do Brasil na dieta do brasileiro e necessario estabelecer melhor exploracao industrial. Portanto, o objetivo deste trabalho foi elaborar uma bebida de soja e castanha do Brasil explorando os beneficios de dois importantes produtos nacionais de alto valor nutritivo. O processo de obtencao da bebida constituiu-se de elaboracao, formulacao e homogeneizacao dos extratos de soja e de castanha do Brasil. Foram estudados cinco niveis (10, 20, 30, 40 e 50%) de extrato de castanha adicionados a bebida de soja. A bebida de soja contendo 30% de extrato de castanha foi a preferida entre os consumidores que participaram deste estudo, demonstrando o beneficio sensorial promovido pela castanha do Brasil. No entanto, ela nao apresentou um melhor desempenho em termos de valor nutricional, exceto pelo teor de oleo. Bebidas a base de soja e castanha do Brasil apresentaram estabilidade visual (sem separacao de fases), apesar da nao estabilidade demonstrada pela bebida de castanha do Brasil isoladamente. Quando o extrato de castanha do Brasil foi acrescentado a bebida de soja, o produto final foi mais branco do que a bebida de soja. Isto e interessante do ponto de vista do consumidor que procura por um extrato de soja mais claro. O processamento da bebida de soja e de castanha do Brasil pode ser uma alternativa para o aumento do uso de castanha do Brasil na dieta dos brasileiros.

Chemical, Technological and Sensory Properties of Wheat Grains (Triticum aestivum L) as Affected by Gaseous Ozonation

Gaseous ozonation, an emerging technology, is applied to microbiological decontamination and to the degradation of residues and contaminants in wheat grains. However, due to its high oxidizing capacity, ozone may cause undesirable effects on the quality of grains or in their derivatives. This study aimed to evaluate the influence of ozone gas on wheat grain quality when exposed to different levels of ozone concentration, exposure time, and grain mass, using a full 23 factorial design. After the milling of ozonized grains, two fractions were evaluated: flour (A) and bran plus germ (B). In fraction A, the quality of the wheat flour was analyzed by both alveography and farinography. The flour extraction rate, falling number and gluten contents were also measured. The chemical and mineral profiles were determined in both fractions. A sensory evaluation, using the difference-from-control test, was applied to investigate the possible differences in aroma or in overall appearance of the flour obtained from the ozonized grains. The results showed that ozone concentration (60 mg/L) positively affected (p < 0.05) the toughness and the falling number of the flour. The other parameters of alveography, as well as farinography, gluten content, chemical composition, mineral, and sensory profiles were not affected (p > 0.05) by ozonation. This study demonstrated that gaseous ozonation, when applied under the conditions of 10 to 60 mg/L, from 2 to 5 h of exposure, grain mass from 2 to 5 kg, does not cause any negative impact on the wheat quality.

Development and nutritional and sensory evaluation of cachapinta (Pseudoplatystoma sp) pâté

This study developed a technique for the preparation of pâté from cachapinta (Pseudoplatystoma sp) waste. For this, frozen minced cachapinta fish was crushed in a mini cutter and homogenized with all other ingredients. The prepared pâté was stored in seamed and thermally treated cans (volume 170 g). Weight proportions of mean moisture, ash, protein, and lipid contents of the minced fish were 75.49, 1.00, 15.00, and 7.92 (g/100 g), respectively. The formulation of the developed pâté is in accordance with legislation for fish products. Cachapinta pâté is a product with high content of polyunsaturated fatty acids, low level of trans fat, and good indices of nutritional quality. Tests of sensory acceptance, purchase intent, and sensory attributes (except spreadability) averaged a score above 6.0, indicating acceptability of the product. Our study suggests that the potential of minced cachapinta for pâté production is high, and that it can contribute a value-added product to seafood consumption.

Influência das condições de cultivo na composição da semente e do óleo de gergelim

Effect of cultivation conditions on the composition of sesame seed and oil Fourteen selected sesame genotypes were grown in Patos, Paraiba State, Brazil and Barbalha, Ceara State, Brazil, and the trials were at a randomized block design with five replicates under non-irrigated and irrigated conditions, respectively. Seeds were evaluated for oil yield and chemical composition, while defatted meal was analyzed for amino acids content. The fatty acids and sterols profiles were also evaluated, as well as the characteristics for identity and oil quality. The differences observed between genotypes in the same area were small. However, significant differences (p <0.05) between the areas for oil content and protein were observed, with higher oil content found for genotypes in Barbalha, where the crop was irrigated. Higher amounts of stearic (C18: 0) and oleic acids (C18: 1) were observed for the oil from Patos, while for linoleic acid (C18:2) a higher content was found in Barbalha oil. As for sterols, campesterol, stigmasterol and delta 5 avenasterol were more abundant for samples from Barbalha, and sitosterol for samples from Patos (p <0.05). Some figures observed for some fatty acids, sterols, density and refractive index diverged from the identity characteristics described in Codex Alimentarius (2001), reinforcing the need to set up a national database that can support future changes in this standard.

Variabilidade genética e associação entre caracteres em germoplasma de pinhão-manso (Jatropha curcas L.)1

A oleaginosa pinhao-manso (Jatropha curcas L.) tem se mostrado uma importante alternativa a producao de biodiesel no Brasil. Objetivando-se conhecer a variabilidade genetica existente na Colecao de germoplasma da UFRRJ, e tambem identificar genotipos de desempenho superior, portadores de atributos importantes ao melhoramento, 60 acessos de J. curcas, aos tres anos de idade, foram caracterizados a partir de 12 descritores morfo-agronomicos. A descricao indicou que as caracteristicas producao de oleo e projecao da copa se mostraram como as de maior variabilidade genetica, ao passo que os atributos intrinsecos as sementes apresentaram os menores valores de variacao. A decomposicao das correlacoes, via analise de trilha, evidenciou importantes associacoes entre a altura de plantas, a projecao da copa, o numero de ramos, o tempo de formacao do fruto e o teor de oleo sobre a producao de oleo por planta. Tal resultado corroborou a possibilidade destas caracteristicas, na Colecao de germoplasma da UFRRJ, serem adotadas como criterio de selecao indireta para a obtencao de genotipos mais produtivos, com porte reduzido e menor periodo de colheita. Pela analise de componentes principais se identificou a producao de oleo e o numero de ramos como as caracteristicas que mais contribuiram para a variacao observada. Os agrupamentos de Tocher e UPGMA promoveram a formacao de sete e oito grupos dissimilares de genotipos, respectivamente, apresentando a possibilidade de serem envolvidos em futuros cruzamentos, e revelando a existencia de uma consideravel variabilidade para as caracteristicas avaliadas.

OXIDATIVE STABILITY OF MACADAMIA AND PISTACHIO OILS

The objective of this work was to evaluate the composition and oxidative stability of macadamia and pistachio oils. Oils from macadamia and pistachio nuts were analyzed for their composition in fatty acids, triacylglycerols and sterols. The Oxidative Stability Index (OSI) of this oils was measured using a Rancimat 679 Metrohm at 98, 110 and 120oC with air flow of 8.33 and 10.0 L/h. Macadamia and pistachio oils were also added to soybean and sunflower oils (in levels of 5 to 20%) to evaluate a possible oxidative stability increase of the latter. Oil samples of macadamia nuts showed as predominance fatty acids, the oleic acid (63.41 to 67.30%) and palmitoleic acid (10.32 to 14.27%) however the major fatty acids in pistachio nut oil samples were oleic (53.83% to 56.85%) and linoleic (31.38% to 32.26%) acids. The OSI at 98°C for macadamia nut oil and for pistachio nut oil reached respectively, 93h and higler than 96h, indicating high oxidative stability. Such values are between the highest found in the literature for vegetable oils in this temperature. A reduction of the OSI occurred when the temperature increased, for both oils. There was only a slight increase in the blends of macadamia and pistachio oils and sunflower and soybean oils.