Erika Madeira Moreira da Silva

Effects of whey protein concentrate, feed moisture and temperature on the physicochemical characteristics of a rice-based extruded flour.

The influence of whey protein concentrate (WPC), feed moisture and temperature on the physicochemical properties of rice-based extrudates has been investigated. WPC (0.64-7.36g/100g rice) was extruded under 5 moisture (16.64-23.36g/100g) and 5 temperature (106.36-173.64°C) established by a 32 central composite rotational design. Physicochemical properties [color, porosimetry, crystallinity, water solubility and absorption, pasting properties, reconstitution test, proximate composition, amino acids, minerals and electrophoresis] were determined. WPC and feed moisture increased redness, yellowness and decreased luminosity. Feed moisture and temperature increased density and total volume pore. WPC and moisture increased crystallinity, but only WPC increased solubility and decrease the retrogradation tendency. Increasing temperature increased the viscosity of the extrudates. The addition of WPC improved the nutritional composition of the extrudates, especially proteins. It is suggested that the extrusion process positively affected the retention of most of the polypeptides chains.

The effect of the addition of whey protein as a substitute for wheat in the development of cakes with no added sugar

Abstract Whey protein (WP) is a product of cheese making which has high nutritional value and functional attributes. Its use in bakery goods favours the physical aspects as well as the emulsion and stabilization capacity and improves the sensory characteristics. The aim of this study was to replace wheat by whey protein in sugar free cakes and evaluate their physical, chemical, microbiological and sensory characteristics. The effect of adding whey protein and margarine on cakes were evaluated using a second order central compound rotational design. The selected treatments were evaluated by means of a sensory analysis and characterized according to their proximate composition and a microbiological evaluation after fifteen days of storage. The addition of up to 11.98 g of margarine per 100 g had an important influence on the reduction in cake height. The treatment with an intermediate WP content (30 g/100 g) and a lower margarine content (6.72 g/100 g) showed better acceptability and a higher protein content when compared to the control cake. The microbiological conditions were satisfactory, conforming to current legislation, even after fifteen days of storage.

Efeito da substituição da farinha de trigo no desenvolvimento de biscoitos sem glúten

O gluten pode determinar a qualidade da farinha de trigo, conferindo as massas caracteristicas como elasticidade e capacidade de absorver agua, o que torna a elaboracao de produtos de panificacao isentos de gluten um desafio. Desse modo, o presente estudo buscou avaliar as caracteristicas fisico-quimicas e sensoriais de biscoitos elaborados com ingredientes sucedâneos ao trigo, como fecula de mandioca, farinha de soja, de quinoa e de amaranto. Para a caracterizacao fisica foram determinados: peso, diâmetro, espessura, fator de expansao e volume especifico. Quanto a composicao quimica foram determinados: umidade, cinzas, proteinas, lipidios, fibras alimentares, carboidratos totais, energia, alem de pH e acidez. A aceitabilidade foi determinada por meio de uma escala hedonica de nove pontos. As formulacoes contendo farinhas sucedâneas ao trigo apresentaram bom rendimento, maior teor de cinzas, de proteinas, de lipidios e de fibras alimentares. Tambem, essas apresentaram percentuais de aceitabilidade superiores a 70%, exceto para a avaliacao do sabor da amostra com maior teor de soja (40 g/100g). Conclui-se que as formulacoes contendo farinhas sucedâneas ao trigo podem ser consideradas promissoras, disponibilizando alternativas alimentares aqueles que almejam produtos com valor nutricional superior e posicionamento unico no mercado, visto que os produtos disponiveis muitas vezes possuem baixo valor nutritivo ao serem elaborados com farinhas amilaceas.

Características físico-químicas e sensoriais de biscoitos diet e comuns preparados com yacon (Smallanthus sonchifolius)

Diet and regular biscuits were prepared using fresh yacon (in natura), besides those including 20 % and40 % of yacon flour. The physical, chemical and sensory characteristics of these biscuits were evaluated.The addition of sugar in the biscuits made from yacon flour (20 % and 40 %) increased the diametervalues. The addition of sweetener (replacing the sugar) in biscuits made from fresh yacon increased thespecific volume value. Regarding to the physical characteristics, no significant differences were evidencedamong the formulated biscuits and their respective controls. In relation to the sensory analysis, biscuitsmade from fresh yacon presented acceptable means, as well as the biscuits made from 20 % yacon flour(with sugar or sweetener). No significant differences were found between the sugar-added biscuits andthe sweetener-added cookies, except for those made from 40 % yacon flour and containing sugar, whichdid not show good acceptability, and neither for purchase intention. Biscuits prepared with yacon flourshowed significantly high fiber contents, being considered as fiber-rich and low-calorie products. Thisinvestigation evidenced that biscuits made from fresh yacon are an excellent option for easy homemadepreparations...(AU) Biscoitos convencionais e do tipo diet foram elaborados utilizando-se yacon fresco (in natura), alem da adicao de 20 % e 40 % de sua farinha. Os biscoitos foram avaliados quanto as caracteristicas fisicas, quimicas e sensoriais. A adicao de acucar nos biscoitos elaborados com farinha de yacon (20 % e 40 %) provocou aumento nos valores de diâmetro. A substituicao de acucar por adocante, nos biscoitos elaborados com yacon fresco, favoreceu o aumento do volume especifico. Nao foram evidenciadas diferencas significativas nas caracteristicas fisicas entre os biscoitos formulados e os respectivos controles. Em relacao a analise sensorial, os biscoitos elaborados com yacon fresco apresentaram medias aceitaveis, bem como os biscoitos preparados com 20 % de farinha de yacon (diet e convencional). Nao houve diferencas significativas entre os biscoitos elaborados com acucar ou com adocante, exceto para aqueles preparados com 40 % de farinha de yacon (com acucar), que nao demonstraram boa aceitabilidade, tampouco quanto a intencao de compra. Os biscoitos preparados com farinha de yacon apresentaram maior conteudo de fibra. Portanto, estes sao produtos ricos em fibras e de baixa caloria. E importante ressaltar que os biscoitos elaborados com yacon fresco sao excelente opcao para serem reproduzidos em preparacoes caseiras...(AU)Diet and regular biscuits were prepared using fresh yacon (in natura) , besides those including 20 % and 40 % of yacon flour. The physical, chemical and sensory characteristics of these biscuits were evaluated. The addition of sugar in the biscuits made from yacon flour (20 % and 40 %) increased the diameter values. The addition of sweetener (replacing the sugar) in biscuits made from fresh yacon increased the specific volume value. Regarding to the physical characteristics, no significant differences were evidenced among the formulated biscuits and their respective controls. In relation to the sensory analysis, biscuits made from fresh yacon presented acceptable means, as well as the biscuits made from 20 % yacon flour (with sugar or sweetener). No significant differences were found between the sugar-added biscuits and the sweetener-added cookies, except for those made from 40 % yacon flour and containing sugar, which did not show good acceptability, and neither for purchase intention. Biscuits prepared with yacon flour showed significantly high fiber contents, being considered as fiber-rich and low-calorie products. This investigation evidenced that biscuits made from fresh yacon are an excellent option for easy homemade preparations.