Thermal studies on protein isolates of white lupin seeds (Lupinus albus)

This study used TG, DSC, and SDS-PAGE techniques to study protein isolates (PIs) in the powder form obtained from lupin seeds flour Lupinus albus. Different methods of preparing PIs were tested, resulting in final products that were different only in relation to the yield and protein content. The results of the protein analysis by SDS-PAGE showed that the same protein fractions were present in the lupin seeds and in the obtained PIs. This result shows that the process of extraction was not damaging to the composition of the original protein. On the other hand, the results of the thermal analysis (DSC and TG-DTG curves) obtained for the different PIs, led to the detection of changes in the protein conformation through the Delta H values, which in general decreased with increasing values of pH and ionic strength in the experimental conditions of extraction.Predilecta Foods (Sao Lourenco do Turvo, SP, Brazil)CAPES Foundation (Brazil

Efeito do consumo de tremoço (Lupinus albus) e seu isolado protéico no metabolismo do colesterol em hamsters hipercolesterolemizados

A soja e outras leguminosas são consideradas alimentos funcionais por apresentarem propriedades hipocolesterolemizantes. Esta propriedade, porém, ainda não foi elucidada para o tremoço e seus isolados protéicos. Um possível componente deste grão responsável pelo efeito redutor de colesterol é sua proteína. Objetivo: Produzir isolado protéico de tremoço e verificar a influência do grão integral e de seus isolados protéicos no metabolismo do colesterol de hamsters hipercolesterolemizados pela dieta. Métodos: O isolado protéico (IP) de tremoço foi produzido por precipitação isoelétrica, utilizando-se pH 10,0 para solubilização da proteína e pH 5,0 para sua precipitação, obtendo-se um isolado protéico de 92,41% de proteína. O IP e a farinha de tremoço integral (FI) foram usados como fonte protéica em dietas experimentais para hamsters que tiveram hipercolesterolemia induzida por dieta contendo 13,5% de gordura saturada e 0,1% de colesterol, por 21 dias. Os animais foram divididos em 3 grupos, recebendo cada grupo dieta com 20% de caseína (controle), dieta com 20% de proteína respectiva do IP e dieta com 20% de proteína respectiva da farinha integral de tremoço (FI), por 28 dias. Resultados: Comparando-se a dieta controle (HC), as dietas IP e FI provocaram reduções significativas no colesterol total (15,3 e 16,88%, respectivamente) e colesterol não-HDL (28,6 e 43,41%, respectivamente). Análises histológicas do fígado foram realizadas e observou-se que o IP e o FI apresentaram efeito hepatoprotetor comparado à HC, que apresentou esteatose difusa e intensa (nível 4+), enquanto que os grupos tremoço integral e isolado protéico apresentaram esteatose focal (nível 1). Alguns possíveis mecanismos envolvidos para o efeito benéfico no metabolismo lipídico foram investigados. A excreção...Soya and other legume seeds are considered functional food because of their hypocholesterolemic properties. However this property was still not elucidated for lupine and its protein isolates. A possible component of this grain responsible for the redactor effect of cholesterol is its protein. Objective: Produce lupine isolate and verify the influence of the whole grain and its protein isolate on cholesterol metabolism in diet hipercholesterolemized. Methods: The lupin protein isolate (PI) was produced by isoelectric precipitation, using pH 10.0 for solubilization of the protein and pH 5.0 to its precipitation, obtaining a protein isolate of 92.41% of protein. The PI and lupine flour whole (FW) were used as source of protein in experimental diets for hamsters that had hipercholesterolemia induced by a 21 days diet containing 13.5% of saturated fat and 0.1% of cholesterol. The animals were divided into 3 groups, receiving each group a 28 days diet with 20% of casein (Control), diet with 20% of protein of protein isolate of lupine (PI) and diet with 20% of protein from lupine whole flour (WF). Results: Comparing the control diet (HC), the diets PI and WF caused significant reductions in total cholesterol (15.3 and 16.88%, respectively) and cholesterol not-HDL (28.6 and 43.41%, respectively). Histological analysis of liver were accomplished and noticed that the PI and the WF presented hepatoprotector effect compared to HC, which presented diffuse and intense steatosis (level 4+), while the groups whole lupine and protein isolate, presented focal steatosis (level 1). Some possible mechanisms for the beneficial effects in lipid metabolism were investigated. The excretion of fecal cholesterol was inversely proportional to the plasmatic levels of the animals cholesterol submitted to the different diets. The animals with the WF diet... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Isolado protéico de farinha de semente de goiaba (Psidium guajava): caracterização de propriedades funcionais e térmicas

A partir da farinha da semente de goiaba (Psidium guajava), cuja composição centesimal é de aproximadamente 6,17 l 0,04% de umidade, 8,43 l 0,12% de proteína e alto teor de fibras, 60,88 l 0,9%, obteve-se isolado protéico (IP) através da precipitação isoelétrica (pI 4,5), cuja fração majoritária pertence à classe das glutelinas. As condições para o preparo do IP foram definidas a partir da curva de solubilidade em água x pH e temperatura de 25 l 3 ºC. Tais condições permitiram obter isolados protéicos com rendimento de extração de 45,2 l 0,5% (pH10,0) e 66,2 l 0,5% (pH11,5) e elevado conteúdo protéico 96,4 l 0,5% e 93,5 l 0,4% respectivamente. A capacidade de absorção de água e óleo foram baixas, apresentando 1,05 l 0,07 e 2,3 l 0,01 mL/g proteína respectivamente para IP 10,0 e 1,65 l 0,07 e 1,70 l 0,07 mL/g pr oteína respectivamente para IP 11,5. A maior capacidade de emulsificação, foi observado para o IP 11,5, 140 l 8 g óleo/g prot., comparado com o IP 10,0, 37 l 2 g óleo/g prot. A formação de gel foi observada em pH neutro e ausência de sal, apresentando as concentrações de 8% para IP 10,0 e 10% para IP 11,5. A cromatografia revelou a presença de dois picos para ambos isolados com sete frações de proteínas de diferentes pesos moleculares. As curvas TG-DTG / DSC revelaram maior quantidade de água para o IP 10,0 e elevada temperatura de estabilidade térmica 200 oC para ambos isolados.From the guava seed flour (Psidium guajava), whose centesimal composition belongs to about 6,17 ??0,04% of moisture, 8,43 ??0,12% of protein and high content of fibers, 60,88 ??0,9%, the protein isolate (PI) was obtained through the isoelectric precipitation (Ip 4,5) whose majority belongs to glutelins class proteins. The conditions for the preparation of the PI was defined from the solubility curve in water x pH and temperature of 25 ??3ºC. Such conditions allowed to obtain protein isolated with extraction yield of 45,2 ??0,5% (pH10,0) and 66,2 ??0,5% (pH11,5) and high protein content of 96,4 ??0,5% and 93,5 ??0,4% respectively. The absorption capacity for water and oil were low, showing 1,05 l 0,07 and 2,3 l 0,01 mL/g protein, respectively, for PI 10,0 and 1,65 l 0,07 and 1,70 l 0,07 mL/g protein, respectively, for PI 11,5. The most emulsification capacity was observed for PI 11,5 (140 l 8 g oil/g prot.), compared to PI 10,0 (37 l 2 g oil/g prot.). The gel formation was observed in neutral pH and salt absence, showing the concentrations of 8% to PI 10,0 and 10% to PI 11,5. The chromatography shows the presence of two peaks for both protein isolated with seven fractions of proteins with different molecular weights. The curves of TG-DTG / DSC revealed high water quantity for PI 10,0 and high temperature for thermal stability 200 °C for both isolates.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Avaliação de algumas propriedades funcionais das farinhas de tremoço doce (Lupinus albus) e feijão guandu (Cajanus cajan (L) Millsp) e sua utilização na produção de fiambre

O aumento na demanda de alimentos no mundo tem motivado pesquisadores a buscarem fontes alternativas a fim de enriquecer nutricionalmente alimentos industrializados e torná-los viáveis economicamente às populações menos favorecidas. O tremoço doce e o feijão guandu são leguminosas com elevado conteúdo proteico e grande potencial de utilização no enriquecimento nutricional de alimentos industrializados, além de desempenharem funcionalidades. Os resultados obtidos neste trabalho permitiram observar que a farinha de tremoço doce é capaz de absorver de 172 a 186% do seu peso em água e de ~62% em óleo, enquanto que a farinha de feijão guandu absorve cerca de 100% de seu peso em água e 50% em óleo. Boa atividade e estabilidade foram observadas para as emulsões obtidas com estas farinhas, indicando potencial de aplicação na produção de embutidos. Objetivou-se neste trabalho, avaliar algumas propriedades funcionais das farinhas de tremoço doce e feijão guandu e sua utilização na fabricação de fiambres. Os fiambres foram elaborados no Laboratório de Controle de Qualidade de Alimentos da Faculdade de Ciências Farmacêuticas da Universidade Estadual Paulista (UNESP), na cidade de Araraquara, com o intuito de oferecer um alimento enriquecido nutricionalmente. Quando comparados ao fiambre elaborado com a adição de concentrado proteico de soja, estes fiambres não apresentaram diferenças significativas nos atributos sensoriais aparência, cor, aroma, textura e impressão global, embora tivessem pouca aceitabilidade sensorial.The increase in food demand worldwide has motivated researchers to seek alternative food crops to nutritionally enrich industrialized foods and make them economically viable to poorer populations. Sweet lupin and faba bean are high protein content legumes of great potential for nutritional enrichment of industrialized foods, besides performing a functional purpose. The results obtained in this work enabled to identify that sweet lupin flour is able to absorb 172 to 186% of its weight in water, and ~62% in oil, while faba bean flour absorbs ~100% of its weight in water, and ~50% in oil. The emulsions obtained with both flours showed good activity and stability, suggesting a good application potential in the production of sausages. In the present work, some functional properties of the sweet lupin and faba bean flours were analyzed, including use in the production of cooked ham. The cooked ham was elaborated in the Quality Control Laboratory of foods in the Pharmaceutical Sciences Faculty in the University of São Paulo State (UNESP) in Araraquara (SP, Brazil), offering an enriched food nutritionally. When compared to cooked hams prepared with the addition of soy protein, the experimental hams presented no significant sensorial differences, such as appearance, color, flavor, texture and overall impression, however they had had little sensorial acceptability.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Avaliação de algumas propriedades funcionais das farinhas de tremoço doce (Lupinus albus) e feijão guandu (Cajanus cajan (L) Millsp) e sua utilização na produção de fiambre Evaluation of some functional properties of lupin sweet flour (Lupinus albus) and faba bean flour (Cajanus cajan (L) Millsp) and their utilization in cooked ham production

O aumento na demanda de alimentos no mundo tem motivado pesquisadores a buscarem fontes alternativas a fim de enriquecer nutricionalmente alimentos industrializados e torná-los viáveis economicamente às populações menos favorecidas. O tremoço doce e o feijão guandu são leguminosas com elevado conteúdo proteico e grande potencial de utilização no enriquecimento nutricional de alimentos industrializados, além de desempenharem funcionalidades. Os resultados obtidos neste trabalho permitiram observar que a farinha de tremoço doce é capaz de absorver de 172 a 186% do seu peso em água e de ~62% em óleo, enquanto que a farinha de feijão guandu absorve cerca de 100% de seu peso em água e 50% em óleo. Boa atividade e estabilidade foram observadas para as emulsões obtidas com estas farinhas, indicando potencial de aplicação na produção de embutidos. Objetivou-se neste trabalho, avaliar algumas propriedades funcionais das farinhas de tremoço doce e feijão guandu e sua utilização na fabricação de fiambres. Os fiambres foram elaborados no Laboratório de Controle de Qualidade de Alimentos da Faculdade de Ciências Farmacêuticas da Universidade Estadual Paulista (UNESP), na cidade de Araraquara, com o intuito de oferecer um alimento enriquecido nutricionalmente. Quando comparados ao fiambre elaborado com a adição de concentrado proteico de soja, estes fiambres não apresentaram diferenças significativas nos atributos sensoriais aparência, cor, aroma, textura e impressão global, embora tivessem pouca aceitabilidade sensorial.<br>The increase in food demand worldwide has motivated researchers to seek alternative food crops to nutritionally enrich industrialized foods and make them economically viable to poorer populations. Sweet lupin and faba bean are high protein content legumes of great potential for nutritional enrichment of industrialized foods, besides performing a functional purpose. The results obtained in this work enabled to identify that sweet lupin flour is able to absorb 172 to 186% of its weight in water, and ~62% in oil, while faba bean flour absorbs ~100% of its weight in water, and ~50% in oil. The emulsions obtained with both flours showed good activity and stability, suggesting a good application potential in the production of sausages. In the present work, some functional properties of the sweet lupin and faba bean flours were analyzed, including use in the production of cooked ham. The cooked ham was elaborated in the Quality Control Laboratory of foods in the Pharmaceutical Sciences Faculty in the University of São Paulo State (UNESP) in Araraquara (SP, Brazil), offering an enriched food nutritionally. When compared to cooked hams prepared with the addition of soy protein, the experimental hams presented no significant sensorial differences, such as appearance, color, flavor, texture and overall impression, however they had had little sensorial acceptability

Thermal behavior of coffee oil (Robusta and Arabica species)

Coffee seeds are a source for obtaining oil which is used in the candy, soluble coffee, and cosmetics industries. The main purpose of this study was the investigation of the lipid profile and thermal behavior of the roasted and in nature coffee oil of Arabica and Robusta species, using thermogravimetry, differential thermal analysis, derivative thermogravimetry, differential scanning calorimetry (DSC), and modulated DSC. Details concerning the thermal decomposition as well as data of the kinetic parameters have been described here. The kinetic studies were evaluated from several heating rates with a sample mass of 10 mg in open crucible under nitrogen atmospheres. The obtained data were evaluated with the isoconversional kinetic method, where the values of activation energy (Ea/kJ mol-1) were evaluated in function of the conversion degree (α). In addition, this oil was evaluated by modulated DSC from 25 to -60 °C, where the transition phase behavior was verified. © 2013 Akadémiai Kiadó, Budapest, Hungary

Study of the thermal behavior of bicuíba oil (Virola bicuhyba)

Bicuíba belongs to the Virola bicuhyba (Schott ex Spreng.) Warb species, Miristicaceas (Myristicaceae) family, which is frequently found in the Atlantic Forest of South and Southeast Brazil. Extraction of the Bicuíba oil was carried out and characterized by gas chromatography. The composition of in nature of this oil indicates that there is a predominance of saturated fatty acids with ~35 % lauric acid and ~40 % myristic acid. Details concerning the thermal behavior were evaluated by thermogravimetry, differential thermal analysis, and differential scanning calorimetry under oxygen and nitrogen atmospheres, showing thermal stability between 208 and 210 °C, respectively. Additionally, the kinetic studies were evaluated from several heating rates with a sample mass of 5 and 20 mg in open crucibles. The obtained data were evaluated with the isoconversional method kinetic, where the values of activation energy (Ea/kJ mol-1) were plotted in function of the conversion degree (α). © 2013 Akadémiai Kiadó, Budapest, Hungary