Angelise Durigon

Efeito do período de maturação de grãos nas propriedades físicas e reológicas de trigo

The aim of this study was to investigate the effect of the maturation period of grains on the physical and rheological properties of wheat flour analyzed by determining the hectoliter weight, weight of thousand grains, experimental milling, proteins, ashes, moisture, color, falling number, alveography, farinography, and damaged starch. Samples of genotypes BRS 179, Rubi, Fundacep 30, Fundacep 51, and 2006/2007 crop, were stored in Kraft paper bags with 10 kg of wheat, at environment temperature of 22 oC and air humidity between 65-75%. Each treatment consisted of one genotype and the measurements were made at zero, 15, 30, 60, and 90 days of maturation. The experiment was carried out in fully randomized factorial design at 4 x 5. The results were analyzed by variance analysis (Anova) and the means compared by Tukeys test at 5% probability. With the increase in the maturation period of wheat, the flour presented the best physical and rheological properties assessed by the changes of the falling number, color, alveography, and farinography. The results of the enzymatic activity, luminosity, yellow intensity, and general gluten strength were effective in the evaluation of physical and rheological properties while the assessments of damaged starch and stability were not appropriate indicators. The wheat should not be sold after harvest, since its commercial classification improvement indicates a maturation period of 60 days. The genotypes of wheat BRS 179 and Fundacep 51 genotypes changed from bland to bread and from Rubi bread to improved indicating higher technological and commercial value with the increase in the maturation period of the wheat grains.

Efeitos de processo de secagem e tempo de armazenamento na qualidade tecnológica de trigo

Neste trabalho, objetivou-se estudar a influencia dos processos de secagem estacionario e intermitente e do tempo de armazenamento na qualidade tecnologica de graos de trigo, cultivar Embrapa 16 colhidos com teor de agua de 15% e 19%. Graos de trigo (Triticum aestivum L) foram produzidos em lavoura comercial da Granja Bretanhas, Cooperativa Arrozeira Extremo Sul, no municipio de Jaguarao, RS. O experimento foi conduzido em delineamento inteiramente casualizado, utilizando dois teores de agua de colheita (15% e 19%), dois processos de secagem (estacionario e intermitente) e quatro tempos de armazenamento. A secagem foi realizada ate o teor de agua de 13% e os graos acondicionados em embalagens de algodao, em sistema de armazenamento convencional pelo periodo de 12 meses. Nos tempos zero, 4, 8 e 12 meses foram realizadas as analises de teor de agua, peso hectolitro, cinzas, lipidios, acidez graxa, numero de queda e alveografia. Os parâmetros mais efetivos para avaliar o efeito dos processos de secagem de trigo intermitente e estacionario em funcao do tempo de armazenamento foram peso do hectolitro, lipidios e acidez graxa indicando melhor qualidade tecnologica na secagem realizada em secador intermitente. O trigo, cultivar Embrapa 16, colhido seco na planta apresentou qualidade tecnologica inferior e menor conservabilidade ao armazenamento do que o colhido de forma antecipada e seco em secador intermitente.

Influência do tipo de farinha de trigo na elaboração de bolo tipo inglês

Wheat flours for cake production must show features such as low protein content, dough extensibility and low gluten strength. The aim of this research was to evaluate the influence of the type of wheat flour in the elaboration of English-type cake using the standard method for laboratory testing proposed by AACC. The wheat flour samples were collected at random from wheat mills in the region, and the other ingredients were obtained at the local market. The wheat flours were characterized according to their crude protein content, damaged starch, alveography and farinography. The repeatability and reproducibility of the methodology was evaluated using one of the flours. The English-type cakes were produced by blending the following ingredients: wheat flour, refined sugar, margarine, milk powder, egg powder, salt, baking powder and water under predefined laboratory conditions. The cakes were evaluated according to their specific volume, water activity, internal characteristics, porosity, crust color and crumb color. The results were analyzed by the analysis of variance and the means compared using Tukey´s test at the 5% significance level. The wheat flour sample showing a value of 68 x 10-4 J was shown to be more suitable for the production of English-type cakes, featuring a greater specific volume and higher score in the evaluation of the sensory characteristics.

Influência dos teores de aveia e de gordura nas características tecnológicas e funcionais de bolos

The present work aimed to study the use of oat and fat in the technological and functional characteristics of cakes. The ingredients used were oat flakes and flour (Avena sativa L.), of the cultivar IAC 7 (30% of toasted thick flakes and 70% of flour), selected based on the chemical composition, wheat flour, sugar, salt, baking powder, emulsifier, powdered milk, whole egg, sorbitol, and vanilla flavor. The experiment was carried out using a central composite rotational design applied to the response surface methodology (RSM). The levels of oat (flakes, flour) and fat were established as independent variables. The results of dough density, dough viscosity, chemical composition, metabolizable energy, specific volume, water activity, internal characteristics, porosity, and color were analyzed by multiple regression; and the significant linear, quadratic, and interaction terms were used in the second order mathematical model. Oat can be used for preparing cakes with reduced caloric value, sources of dietary fiber, which are characteristics of functional foods. The dough density varied with the amount of fat added in the formulation while the viscosity varied with the oatmeal concentration. The porosity of the cake crumbs was influenced by the oatmeal and fat concentrations used in the formulations. With the increase of the oat level and decrease of fat in the formulations, the average area, diameter, and perimeter of the alveoli increased.

Emprego do método número de queda fúngico na determinação da atividade de alfa-amilase em farinha de trigo

Summary The quantity of fungal alpha-amylase used in wheat flour must be controlled since an excess negatively affects the baking process. Since the classical falling number method does not quantify fungal alpha-amylase, a method must be used that does determine the amount present. The aim of this work was to study the fungal falling number method in the determination of the amylolytic activity of wheat flour, and to evaluate its influence on the functional properties of the loaves. Four wheat flour samples were characterized with respect to their moisture, crude protein and damaged starch contents, and also alveography and falling number. Concentrations of 0, 0.028, 0.056 and 0.084 g.kg –1 of fungal alpha-amylase in the treatments were evaluated, determining the falling number and carrying out baking tests. The results were analyzed by the analysis of variance and the comparison of means by Tukey’s test at the 5% level of significance. The flour characterization results showed that the values for dough deformation energy (W) correlated with the percentage of damaged starch, and there was no relationship between W and the percentage of crude protein. The amylolytic activity proportionally reduced the amount of fungal alpha-amylase added. This method is appropriate to predict the total amount of amylolitc enzymes present in wheat flour, producing better loaf volume yields and crust colours when fungal alpha-amylase concentrations of 0.056 and 0.084 g.kg – ¹ were used.