Luciana H. Maia

Efeito da pressão de homogeneização nas propriedades funcionais do leite de soja em pó

O leite de soja foi submetido a diferentes pressoes (3.000; 4.000; 5.000 e 6.000 psi) de homogeneizacao e em seguida, foi seco por atomizacao. As propriedades funcionais destes leites de soja em po foram estudadas. Observou-se que houve melhoria na absorcao de gordura, indice de dispersibilidade de proteina, indice de solubilidade de nitrogenio e nas propriedades emulsificantes com o aumento da pressao de homogeneizacao ate 5.000 psi. Os valores numericos para as propriedades espumantes nao foram relevantes, embora as mesmas tenham sido tambem afetadas pelas diferentes pressoes de homogeneizacao. Recomenda-se, portanto, o leite de soja em po submetido previamente a homogeneizacao de 5.000 psi, para o uso em produtos de carne, bebidas, sopas, molhos, produtos de confeitaria e de chocolataria.

Características químicas dos mingaus desidratados de arroz e soja

The objective of the present work was the chemical characterization of dehydrated porridges of rice and soybean at different proportions, 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50%, respectively. Steps for their manufacture included: soybean seed dehulling, blanching, disintegration of blanched rice and soybean, homogenization and spray drying. Chemical characterization was undertaken through proximate composition, mineral and amino acid contents, and trypsin inhibitor activity. An increase in the soybean proportions (0 to 50%) resulted in an increase in the content of protein, oil, ash, crude fiber, phosphorus, calcium, potassium, magnesium, iron, copper, zinc, selenium, manganese and molybdenum, but a decrease in the percentage of carbohydrate, sodium and chromium. Cobalt content did not change. The contents of potassium, magnesium, iron and cooper in the dehydrated rice-soybean porridges with 40 and 50% soybean, were high and were comparable with those met in the RDA for infants. With the exception of the sulfur-amino acids, better essential amino acids (EAA) profiles were obtained as the proportion of soybean increased. EAA composition was comparable to the EAA patterns from FAO/WHO for infants, except for lysine and methionine contents. Dehydrated rice-soybean porridges with 30, 40 and 50% soybean presented the highest lysine contents for preschool children, satisfying the requirement for school children. On the other hand, methionine was not limitant for both preschool and school children. No activity of trypsin inhibitor was detected.

Mingau de arroz e soja pronto para consumo

Com o objetivo de estudar um mingau pronto para consumo com boas caracteristicas sensoriais e estabilidade coloidal aparente, foi preparada uma mistura de arroz e soja em diferentes proporcoes, considerando as seguintes etapas de processamento: decorticagem dos graos de soja, branqueamento, desintegracao e homogeneizacao do arroz e soja. Os mingaus formulados foram avaliados sensorialmente e analisados quanto a composicao centesimal, mineral e indice de separacao. Os mingaus formulados com 80:20, 70:30 e 60:40% de arroz:soja foram os de melhor aparencia, sabor e textura. Entretanto, quando os mesmos foram aromatizados com baunilha, os mingaus com 30 e 40% de soja foram os preferidos, e quando com coco, apenas o mingau com 40% de soja foi o preferido pela equipe massal de provadores. Esses mingaus formulados apresentam excelente estabilidade coloidal aparente e boa composicao em minerais.

Viscosidade de pasta, absorção de água e índice de solubilidade em água dos mingaus desidratados de arroz e soja

Dehydrated porridges containing rice and soybean in different proportions (100:0; 90:10; 80:20; 70:30; 60:40 and 50:50%) were assessed as to their pasting viscosity, water absorption (WA) and water solubility index (WSI) in order to verify their potential use as food ingredients. Steps for manufacture of the dehydrated porridge included: soybean seed dehulling, blanching, disintegration of blanched rice and soybean, homogenization and spray drying. The results indicated that increasing soybean proportions from 0 to 50% showed an increase in maximum viscosity temperature and WSI, a decrease in maximum viscosity, minimum viscosity at constant temperature, final viscosity at cooling cycle and WA. Numeric values associated with the studied properties remained relatively high consequently, the dehydrated rice-soybean porridges may be recommended as infant food or as an ingredient for baking and meat products.

Características sensoriais de leites de soja reconstituídos

Foram estudadas a viscosidade aparente e as caracteristicas sensoriais dos leites de soja reconstituidos, elaborados com leites de soja em po submetidos previamente a homogeneizacao em diferentes pressoes (3.000, 4.000, 5.000 e 6.000 psi). Verificou-se que a viscosidade aparente aumentou progressivamente com o aumento da pressao de homogeneizacao. As pressoes de 4.000, 5.000 e 6.000 psi de homogeneizacao resultaram na obtencao de leites de soja reconstituidos de melhor aparencia, sabor e textura, sendo os com sabores de baunilha e coco elaborados com leites de soja em po submetidos previamente a pressoes de 4.000 e 5.000 psi de homogeneizacao igualmente preferidos pela equipe massal de provadores nao-treinados. Portanto, os melhores niveis de viscosidade aparente que se correlacionam com o corpo sao 21 e 26 centipoises, ou seja, o uso de 4.000 e 5.000 psi na pressao de homogeneizacao, respectivamente.

Estudo das propriedades reológicas e sensoriais após reconstituição dos mingaus desidratados de arroz e soja

With the purpose of obtaining dehydrated rice-soybean porridges with good rheological and sensory properties when reconstituted, rice and soybean were mixed using the following proportions (w/w): 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50%, respectively. The process steps included: soybean seeds dehulling, blanching, disintegration of blanched rice and soybean, homogenization and spray drying. The obtained dehydrated porridges were reconstituted in water in a 1:9 (mixture:water) proportion, and then evaluated for their compositions, trypsin inhibitor activity and rheological properties. With the exception of the control (0% soybean), all reconstituted porridges were submitted to sensory evaluation regarding to their appearance, consistency and flavor. The results indicated that all reconstituted porridges (0 to 50% soybean) presented pseudoplastic behavior. Porridges containing 20, 30, 40 and 50% soybean showed better consistency. Those containing 30, 40 and 50% soybean showed better appearance and flavor. These reconstituted porridges were then formulated with 6% sugar, 0.2% salt and 0.6% flavor (vanilla and coconut) and evaluated for consumer preference. Results indicated that formulated porridges containing 40 and 50% soybean, flavored with vanilla, were preferred. From those with coconut, only the one containing 40% soybean was acceptable. No activity of trypsin inhibitor was detected.

Influência da proporção arroz:soja sobre a solubilidade e as propriedades espumantes dos mingaus desidratados

Dehydrated rice-soybean porridges at different proportions (100:0, 90:10, 80:20, 70:30, 60:40 and 50:50%) were assessed for solubility and whipping properties, in order to verify their use as food ingredients. Dehydrated porridge was manufactured by soybean seed dehulling, blanching, disintegration of blanched rice and soybean, homogenization and spray drying. Chemical analysis showed that increasing soybean proportion from 0 to 50%, resulted in an increase in the soluble nitrogen in water, nitrogen solubility index (NSI), dispersible protein in water, protein dispersibility index, expansion and syneresis of foam, and a decrease in the foam volume after 30 and 60 min. However, NSI of only dehydrated porridge with more than 10% soybean showed the highest values, whereas the whipping properties values were not significant in non dehydrated porridge. Therefore, the dehydrated rice-soybean porridges with 20, 30, 40 and 50% soybean, would be recommended for use in porridges, beverages, soups and sauces, where the presence of foam is not desirable. No trypsin inhibitor activity was detected in studied dehydrated porridges.