Pasting and thermal properties of fermented cassava (Manihotesculenta Crantz).

Cassava (Manihotesculenta Crantz) is used in various applications and recipes worldwide. The natural fermentation of this root flour produces the "puba", a typical food from the north of Brazil. The evaluation of the qualities of the puba flour is little explored, thus, this study aimed to evaluate the pH (of the fermentation liquid), the texture of cassava pieces after a fermentation process, puba flour instrumental color parameters and its thermal and pasting properties. The pH and the force decreased with the incubation time. Puba flour from 3 to 7 days had the highest lightness, being good for food application. "a" and "b" values showed that the roots tended to a light blueish green due to post-harvest degradation and fermentation. The results of DSC analyses demonstrated that there was no significant difference in the gelatinization initial temperature between days 1-7, as well, no significant changes were observed in gelatinization peak temperature, conclusion temperature and gelatinization enthalpy. For the paste properties, the viscosity peak and breakdown slightly increased, and no significant changes as observed in final viscosity, setback and paste temperature on the days of fermentation. Therefore, the fermentation conditions (size of the pieces), the microorganisms (intrinsic of the material), and the time of seven days was not enough to promote drastic changes in the granules of cassava starch.

Chemical profile of colorful bean (Phaseolus vulgaris L) flours: Changes influenced by the cooking method.

This study aimed to determine how the cooking methods change the phenolics and saponins profiles, oligosaccharides, antinutrients and antioxidant properties of flours from colorful beans. The autoclave cooking consisted of: 6 h soaking and 5 min cooking (C5); and 20 min cooking without soaking (C20). Both cooking methods significantly promote changes on the chemical compounds studied, and the intensity of these variations were affected by the cultivars. Most of flours of C5 beans presented a lower loss of anthocyanins (3.9-70.0%), DPPH (11.7-87.2%), ABTS (0.0-82.7%), and tannins (0.0-90.0%) compared with C20. The cooked flours of Artico and Realce showed some similarities among chemical compounds, as well as the lowest concentration of tannins (0.0 mg‧g-1), antioxidant activity (0.40 µmol Trolox‧g-1), and higher amounts of oligosaccharides and acetylcholine. Most of cooked flours presented a reduction in phenolics and soyasaponins αg and ßg, and an increase in soyasaponins Ba and I and oligosaccharides (mainly C20 flours).

Physicochemical, structural, and thermal properties of "batata-de-teiú" starch.

Jatropha elliptica (Pohl) Muell Arg is a sub-shrub herbaceous plant native to the Brazilian Cerrado, and popularly known as "batata-de-teiú". There is lack of scientific knowledge about the structural characterization, physicochemical and technological aspects of the carbohydrate content present in Jatropha elliptica roots. Thus, this work aim contributes with new data about the evaluation of chemical-structural, thermal and technological properties of starch extracted from "batata-de-teiú". The starch presented low levels of ash, protein and total fiber and amylose content of 32.82%. The initial gelatinization temperature of "batata-de-teiú" starch was 70.1 °C, peak temperature was 73.84 °C and final 85.52 °C, and starch had low trend to retrogradation. The results of x-ray and 13C cpmass show a A-type structure with high crystallinity degree. Finally, this results suggested that the "batata-de-teiú" starch is a macromolecular structure with high branching degree, favoring intermolecular Coulomb, Van der Waals forces and hydrophobic interactions, which directly corroborated with the low solubility observed (maximum of 6.44 g·100 g-1 at 80 °C). The extraction of "batata-de-teiú" starch can be viable, and it has technological characteristics suitable for use in the food industry or pharmaceuticals, since "batata-de-teiú" starch has good thermal stability and low trend to retrogradation.

Aging indicators for stored carioca beans.

High temperature, moisture content and radiation conditions, common in the tropics, accelerate the physiological post-harvest disorders in beans, affect integument color and bean hardness. This study explored the darkening and hardening mechanisms in carioca type beans during storage. The contrasting genotypes for bean darkening and hardening (BRS Estilo and BRS Pontal: rapid darkening and hardening; BRSMG Madrepérola and CNFC 10467: slow darkening and partially resistant to hardening; and a Canadian genotype of the Pinto Bean type resistant to darkening (negative control)) were evaluated right after harvest and after six months storage at 20.3 ±â€¯0.2 °C and 78.9 ±â€¯6.0% RH, with respect to their physicochemical, biochemical and morphological attributes. All the samples hardened with time, but the velocity of darkening did not always parallel the degree of hardening of the beans (that increase linearly with time), which indicates that the color of the bean integument was not a safe indicator to predict the culinary quality of carioca beans. During storage, the SOD (superoxide dismutase) activity and LP (lipid peroxidation) in the cotyledon increased, and the increase was more significant in the integument of the rapid-darkening genotypes. The oxidative stress detected in the beans apparently started in the green bean formation phase, continuing during post-harvest, especially for the rapid-darkening beans. Quantification of the bivalent ions in the bean fractions, together with the degree of membrane damage was positively associated with bean darkening, independent of the group. Thus, aging of the carioca beans could be triggered by a complex mechanism involving diverse intrinsic factors in different degrees according to the genotype and the post-harvest period, but some parameters could serve as indicators, as cooking time, hardness and color, to differentiate between rapid and slow darkening beans.

Extraction, characterization and technological properties of white garland-lily starch.

The white garland-lily rhizomes represent a potential source for starch extraction. Thus, the present study aimed to contribute with new data about the starch extraction yield and to characterize the chemical-structural, thermal and technological properties of the white garland-lily starch. The rhizomes harvested in the dry season presented greater starch yields (22.0 g 100 g-1) than in the early summer (6.9 ±â€¯0.5 g 100 g-1) (d.b). The starch presented adequate purity (97.67 g 100 g-1), the granules were flat, with the thickness varying from 2 to 6 µm and length between 12 and 38 µm, and they showed no birefringence. They presented an amylose content of 59.16 g 100 g-1, crystallinity of 19.30% and type B starch. The C13 CP/MAS spectrum presented an amorphous pattern although indicating a transition to type V. This was a product with moderate swelling power and a high gelatinization peak temperature (76.78 °C). The extraction of white garland-lily starch is feasible in the dry season when it has chemical-structural, thermal and technological properties suitable for use in the food industry, related to its high amorphous starch content.

Nutritional value of gluten-free rice and bean based cake mix / Valor nutricional de mistura de bolo sem glúten a base de arroz e feijão

ABSTRACT: Gluten-free foods are a growing trend in the domestic and international markets, contributing to health and wellness, especially the celiac public. The objective of this study was to create a new option of gluten-free food by replacing wheat flour by rice grit flour, cornstarch, and extruded split bean flour, and to aggregate value to low cost industrial byproducts. A new food product was developed and its components analyzed for their nutritional characteristics and changes during baking. The baked cakes can be a source of protein, had a good starch and protein digestibility, and low antinutritional factors, notably tannins. Incorporation of an extruded bean flour in a gluten-free cake mix improves protein digestibility, total dietary fiber, and raises ash, iron, and zinc contents.

RESUMO: Os alimentos sem glúten são uma tendência crescente no mercado doméstico e internacional, contribuindo para a saúde e o bem-estar, principalmente do público celíaco. O objetivo deste estudo foi desenvolver novas opções de alimentos sem glúten, substituindo a farinha de trigo por farinha de arroz, amido de milho e farinha de feijão extrusada, agregando assim valor a subprodutos industriais de baixo custo. Um novo produto alimentar foi desenvolvido e seus componentes analisados quanto às suas características nutricionais e alterações durante o cozimento. Os bolos assados podem ser fontes de proteínas, possuem boa digestibilidade de amido e proteínas e baixos fatores antinutricionais, principalmente taninos. A incorporação da farinha de feijão extrusada na mistura para bolos sem glúten melhorou a digestibilidade das proteínas, a fibra alimentar total e aumentou o teor de cinzas, ferro e zinco.

Physicochemical and technological characteristics of arrowroot flour modified by ultrasound and low-temperature heat treatment / Características físico-químicas e tecnológicas da farinha de araruta modificada por ultrassom e por tratamento térmico de baixa umidade

ABSTRACT: Arrowroot is a plant abundant in starch content, and because it does not possess gluten proteins in its composition, its utilization is of great interest in the production of food for people who are intolerant to these proteins. The substitution of gluten involves the use of thickening agents, such as pre-gelatinized starches or flours, which can be obtained by physical processes. In this context, the aim of this study was to evaluate the physicochemical and technological characteristics of arrowroot flour (AFU) modified by ultrasound, in the functioning of intensity and time, and modified by low humidity heat treatment (LHHT) as a function of temperature and time. Besides characterizing AFU and AFLHHT, we aimed their future application in products without gluten. All independent variables affected (P<0.05) water absorption index (WAI) and water solubility index (WSI) at 28 °C; WSI was at 80 °C, peak viscosity, final viscosity, setback and enthalpy of gelatinization (ΔH). The selected AFU was processed in 15 min at an ultrasound intensity of 43.5%, while AFLHHT was at 105 °C for 15 min. Neither of them presented significant differences in relation to their proximal composition. It is concluded that the modification of AF by both methods is feasible, and it is possible to predict its use in the formulation of foods without gluten, due to their physicochemical and technological characteristics which are more appropriate than those of AF.

RESUMO: A araruta é uma planta que apresenta conteúdo abundante de amido, e por não apresentar as proteínas do glúten em sua composição desperta o interesse da sua utilização na produção de alimentos para pessoas intolerantes a essas proteínas. A substituição do glúten envolve a utilização de agentes espessantes, como amidos ou farinhas pré-gelatinizados, que podem ser obtidos por meio de processos físicos. Neste contexto, o objetivo deste estudo foi avaliar as características físico-químicas e tecnológicas da farinha de araruta (FA), FA modificada por ultrassom (FAU) em função da intensidade e tempo, e FA modificada por tratamento térmico de baixa umidade (FATTBU) em função da temperatura e tempo, além de caracterizar FAU e FATTBU selecionadas, visando sua futura aplicação em produtos sem glúten. Todas as variáveis independentes afetaram (P<0.05): índice de absorção de água (IAA) e o índice de solubilidade em água (ISA) a 28 °C, ISA a 80 °C, viscosidade de pico, viscosidade final, tendência a retrogradação e entalpia de gelatinização (ΔH). A FAU selecionada foi processada em 15 min em intensidade do ultrassom de 43,5%, enquanto FATTBU a 105 ºC por 15 min. Ambas não apresentaram diferenças significativas em relação à composição proximal. A modificação da FA tanto por ultrassom como por tratamento térmico com baixa umidade é viável, e é possível prever a sua utilização na formulação de alimentos sem glúten, devido as suas características físico-químicas serem mais apropriadas que a da FA.

Roasting soybeans in a microwave for manufacturing chocolate dragées / Torração de soja em micro-ondas para desenvolvimento de drágeas de chocolate

ABSTRACT: This study aimed to evaluate the effect of different microwave-roasting timeson different sizes of soybean grains with black tegument to achieve the best crunchiness, flavor, and hardness. Black soybean dragées- containing a soybean core coated with layers of chocolate (dragée) - were manufactured, and their nutritional value, microbiological risk, acceptability, and consumer-purchase intentions were verified. Flavor and crunchiness of the roasted black soybeans wereonly affected by the roasting time in the microwave, whereas the hardness was only affected by grain size. The best core of the dragéewas obtainedusing grains ofsieve size 15 (large grains) roastedin the microwave for 11 min; this core presented higher frequencies for extremely crunchy notes (56%), toasted flavor (61%), and an instrumental hardness close to that of the existing commercial product (33.17 N). The manufactured dragées did not present resistant starch, anthocyanins, and microbiological risk, and they were sensorially accepted by the tasters (mean scores of 7.77 for texture and 8.36 for appearance on a scale of 1 to 9). Thus, roasted black soybean dragéeshave a high marketing potential from technological, nutritional, and sensorial points of view.

RESUMO: Este estudo objetivou avaliar o efeito do tempo de torra no micro-ondas para diferentes tamanhos de grãos de soja tipo alimento de tegumento preto, de forma a atingir a melhor crocância, sabor e dureza, e em seguida caracterizar o seu confeito, estruturado na forma de núcleo e camadas de cobertura de chocolate (drageados), em relação ao valor nutricional, risco microbiológico, aceitabilidade e intenção de compra pelos consumidores. O sabor e a crocância da soja preta torrada foram afetados somente pelo tempo de torra em micro-ondas, enquanto a dureza somente foi afetada pela dimensão dos grãos. O melhor núcleo (selecionado) foi obtido com os grãos de peneira 15 (grãos grandes), no tempo de 11 min de torra em micro-ondas, pois apresentou maior frequência para as notas de extremamente crocante (56%), sabor de torrado (61%), e uma dureza instrumental próxima ao produto comercial (33,17 N). As drágeas não apresentaram amido resistente, antocianinas e risco microbiológico, e foram sensorialmente aceitas pelos provadores (scores médios de 7,77 para textura e 8,36 para aparência, em uma escala de 1 a 9). Portanto, o drageado de soja preta torrada com chocolate é viável do ponto de vista tecnológico, nutricional e sensorial, com alto potencial de comercialização.