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1.
Int J Biol Macromol ; 263(Pt 2): 130370, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403222

RESUMO

Dry heat treatment (DHT) has been demonstrated as a viable method for starch modification, offering benefits due to its environmentally friendly process and low operational costs. This research modified potato starch using different DHT conditions (continuous-CDHT and cyclic-RDHT), with durations ranging from 3 to 15 h and 1 to 5 cycles, at 120 °C. The study investigated and compared the structural, thermal, pasting, and morphological properties of the treated samples to those of untreated potato starch, including in vitro digestibility post-modification. DHT altered the amylose content of the biopolymer. X-ray diffraction patterns transitioned from type B to type C, and a decrease in relative crystallinity (RC%) was observed. Morphological changes were more pronounced in starches modified by RDHT. Paste viscosities of both CDHT and RDHT-treated starches decreased significantly, by 61.7 % and 58.1 % respectively, compared to native starch. The gelatinization enthalpy of RDHT-treated starches reduced notably, from 17.60 to 16.10 J g-1. Additionally, starch digestibility was impacted, with cyclic treatments yielding a significant increase in resistant starch content, notably an 18.26 % rise. These findings underscore the efficacy of dry heat in enhancing the functional properties of potato starch.


Assuntos
Solanum tuberosum , Solanum tuberosum/química , Temperatura Alta , Amido/química , Amilose/química , Viscosidade , Difração de Raios X
2.
Braz. arch. biol. technol ; 64(spe): e21200693, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1278464

RESUMO

Abstract Slowly digestible starch (SDS) and resistant starch (RS) associate with health benefits when present in the diet. This study aimed to evaluate ready-to-eat corn and cassava flours regarding their commercial presentation (dry or flaked), composition and in vitro digestibility of starch. Sixteen samples from Southern Brazil were procured in the market: eight dry cassava flours, six biju-type (flaked) corn flours and two biju-type cassava flours. Dry cassava flours had higher L* and lower b* values, and higher RS, relative crystallinity and viscosity peak values. Dry cassava flour partially preserves granular starch, as its processing involves lower drying temperatures and lower moisture of the pressed pulp. Dry cassava flours that had higher b* values also had higher rapidly digestible starch (RDS) levels, since higher temperatures are required in their production. Both biju-type flours showed the highest RDS values and no RS due to processing with elevated temperature and high moisture of the pressed pulp. In this study starch digestibility from the flours depended on processing, with minor influence of the raw material, fiber content and granulometry. The whiter and the smaller the granulometry of the dry cassava flours, the better they showed as potentially health benefiting.


Assuntos
Humanos , Indústria de Farinhas , Mucosa Gástrica , Amido Resistente/análise , Brasil , Manihot , Zea mays
3.
Braz. arch. biol. technol ; 64: e21200568, 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1278450

RESUMO

Abstract Sweet potato (SP) starchy roots have a broad range of colors, high-quality nutritional composition including bioactive substances (anthocyanins and β-carotene), vitamins, minerals, dietary fiber and starch. Several studies report the versatility of this root crop as part of the human diet and its possible health benefits. In this review the SP chemical composition, nutritional properties and its potential use in food processing for developing nutritious and healthy products are explored. Due to the adaptation of sweet potatoes to several agricultural managing conditions, accepting low technology /low cost with reasonable performance, it has called attention as a strong candidate of accessible functional food market.


Assuntos
Amido , Ipomoea batatas , Tubérculos , Farinha , Compostos Fitoquímicos
4.
Braz. arch. biol. technol ; 63: e20190759, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1132246

RESUMO

Abstract Animal products are sources of microbiological contamination when the process has hygienic-sanitary control fails. Therefore, this work aims the evaluation of the pathogenic microorganisms presented in samples from the Brazil southern region of yogurt (N = 101), stretched curd cheese (N = 31), fresh sausage (N = 22) and processing water (N = 63). Analyses of coliforms at 45 °C, Staphylococcus aureus, Salmonella sp. and Escherichia coli were performed. Analysis indicated processing water is an important contamination source to be monitored, because the majority of samples presented results above the regulation limits. Thermal treatment and fermentation such as stretched curd cheese and yogurt appeared to be more stable against contamination during processing. In this study, for coliforms at 45 °C, only one cheese sample and 12% of total yogurt samples exceeded the Brazilian legislation limit. None of sausage samples presented any contamination. On the other hand, values found in both processing water and dairy products indicated failures in application and monitoring of good manufactured practices.


Assuntos
Animais , Microbiologia da Água , Iogurte/microbiologia , Queijo/microbiologia , Microbiologia de Alimentos , Produtos da Carne/microbiologia , Salmonella/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Brasil , Escherichia coli/isolamento & purificação , Coliformes
5.
Food Chem ; 301: 125304, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394335

RESUMO

Black rice is a variety of pigmented rice. It contains numerous nutritional and bioactive components, including essential amino acids, functional lipids, dietary fibre, vitamins, minerals, anthocyanins, phenolic compounds, γ-oryzanols, tocopherols, tocotrienols, phytosterols and phytic acid. There have been several studies of black rice due to its alleged beneficial health effects when consumed regularly. This review focuses on the historical aspects, chemical composition, and nutritional and functional properties of black rice. Furthermore, a discussion of the development of new foods and beverages with applications and processing technologies designed to improve their quality attributes. The nutritional value of black rice means that it has the potential to be used in the production of healthy foods and beverages, such as functional products and gluten-free cereals, thereby providing extra health benefits to consumers.


Assuntos
Indústria de Processamento de Alimentos/métodos , Valor Nutritivo , Oryza/química , Oryza/fisiologia , Antocianinas/análise , Fibras na Dieta/análise , Minerais/análise , Fenóis/análise , Tocoferóis/análise , Tocotrienóis/análise
6.
Braz. arch. biol. technol ; 62: e19180470, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989423

RESUMO

Abstract The effects of gamma radiation (0, 1, 2 and 3 kGy) were used to evaluate the stability and thermal degradation kinetics of anthocyanins, as well as the stability of total phenolic compounds (TPC) and antioxidant activity at different temperatures (4, 25, 35 and 45 °C) during the storage (0, 30, 60, 90 and 120 days) of black rice flour. This flour can be used as ingredient for gluten-free cereal products with higher nutritional value. For this it is necessary to preserve the anthocyanin content during thermal processing and shelf-life periods. At time 0, the dose of 3 kGy provided all of the most available bioactive compounds, raising their antioxidant potential, except for TPC. During the storage at different temperatures up to 120 days, gradual losses occurred in all the analysed parameters. Regarding the total anthocyanin content and TPC, the sample irradiated with a 1 kGy dose remained most stable. The analysis of kinetic data indicated a first-order reaction for the degradation of anthocyanins. The combination of irradiation with different temperatures may improve the shelf-life of black rice flour.


Assuntos
Radiação , Oryza , Termodinâmica , Compostos Fitoquímicos , Antocianinas/química
7.
Food Chem ; 264: 435-442, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29853398

RESUMO

Organic amaranth starch (Amaranthus caudatus) was studied after heat-moisture treatment (HMT) using different moisture contents and different times. The starch extracted by the aqueous method presented low lipid and protein content. After HMT, an increase in the thermal stability was identified. The onset and peak temperatures were higher with an increase in moisture content and the times used in the modification. The gelatinisation enthalpy varied due to the heterogeneity of the crystals formed after the structural reorganisation caused by HMT. The relative crystallinity was lower for the physically modified starches. An increase in the pasting temperature was accompanied by a decrease in the viscosity, setback and breakdown, which were proportional to the moisture and time used. The morphology of the HMT-modified samples was not altered; however, agglomerations were noted. Low levels of dispersion homogeneity and suspension stability were observed for the modified samples due to the strong presence of agglomerates.


Assuntos
Amido/análise , Água/química , Amaranthus/metabolismo , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Amido/química , Temperatura , Termogravimetria , Viscosidade , Difração de Raios X
8.
Braz. arch. biol. technol ; 54(4): 701-708, July-Aug. 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-595622

RESUMO

The study aimed to investigate the antihyperglycemic and antilipidperoxidative effects of ethanol extract of the dry matter from culture broth of Coriolus versicolor (ECBC) in streptozotocin-induced diabetes mice. Blood glucose level, insulin level, total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol(LDL-C), high density lipoprotein -cholesterol (HDL-C) in serum and reduced glutathione level (GSH), lipid peroxidation, glycogen, antioxidant enzymes in liver were evaluated. Moreover, histopathological observation was conducted. Streptozotocin treatment (150 mg/kg body weight) induced the decrease of GSH level, antioxidant enzymes activities, glycogen content in liver, HDL-C content and insulin level in serum, accompanied by the elevation of the lipid peroxidation in liver, serum blood glucose level, contents of TC, TG and LDL-C. Treatment with ECBC restored the changes in the above parameters up to the basal level. The protective effects were further supported by the attenuation of the degree of pancreas damage in ECBC treated mice.

9.
Hig. aliment ; 25(196/197): 138-141, maio-jun. 2011. tab
Artigo em Português | LILACS | ID: lil-616615

RESUMO

A carne devido a sua composição pode favorecer o desenvolvimento de diversas bactérias. O presente estudo teve como objetivo avaliar de 2003 a 2008 diversos tipos de salames provenientes de várias cidades do Paraná. As cidades foram agrupadas por regiões e três micro-organismos foram analisados: Staphylococcus coagulase positiva, coliformes a 45°C e Salmonella sp. Observou-se pela análise, condenação por coliformes na maioria dos casos (47,22%) e a região Sudoeste foi a que apresentou maiores problemas (86,11%)


Assuntos
Contaminação de Alimentos , Amostras de Alimentos , Produtos da Carne/microbiologia , Brasil , Coliformes , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação
10.
Hig. aliment ; 25(194/195): 187-191, mar.-abr. 2011. ilus
Artigo em Português | LILACS | ID: lil-607088

RESUMO

Com a finalidade de avaliar a eficiência dos métodos rápidos para a detecção de Coliformes totais e E. coli, foi testada uma metodologia utilizando a técnica do número mais provável NMP para Coliformes totais e E. coli e duas metodologias para Salmonella sp. Foram submetidas à pesquisa de Coliformes 12 amostras de vários alimentos e para a pesquisa de Salmonella sp. 6 amostras de produtos derivados da soja e uma amostra de peito de frango. Os resultados demonstraram não haver diferença para a detecção de E. coli sendo assim, uma metodologia alternativa para informar os resultados de E.coli em apenas 48 horas. Os resultados de Coliformes totais, porém,no método rápido apresentaram-se mais elevados que na metodologia tradicional. Para a pesquisa de Salmonella apenas uma técnica apresentou resultados compatíveis com a metodologia tradicional, permitindo sugeri-la como método de escolha para a pesquisa de Salmonella sp, em alimentos.


Assuntos
Contaminação de Alimentos/análise , Indústria Alimentícia , Microbiologia de Alimentos , Amostras de Alimentos , Método de Tubulação Múltiplo , Coliformes , Salmonella/isolamento & purificação
11.
Braz. arch. biol. technol ; 52(spe): 143-150, Nov. 2009. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-539860

RESUMO

Starch nutritional fractions as well as thermal properties and other analysis are essential for food and industrial application. Cassava bagasse is an important agro-industrial residue and its starch content was evaluated using two alternative methods. Thermal characterization and microscopy analyses helped to understand how hydrolysis digests starchy fraction of cassava bagasse. The melting point of cassava starch occurred at 169.2ºC. Regarding TG analyses, after moisture content, there were observed two main mass losses for all samples. Results suggest hydrolysis carried out using enzyme is less effective in order to convert total starch content in cassava bagasse. However, using sulfuric acid, fibers are affected by analyses conditions.


As frações nutricionais bem como as propriedades térmicas e outras análises são essenciais para a indústria de alimentos e suas aplicações O bagaço de mandioca é um importante resíduo agroindustrial e seu teor de amido foi avaliado por dois métodos alternativos. A caracterização por análise térmica e microscopia ajudou na compreensão de como a hidrólise digere a fração amilácea do bagaço de mandioca, O ponto de fusão foi de 170ºC, a análise termogravimétrica (TG) mostrou após a perda de umidade do material, duas principais perdas de massa em todas as amostras analisadas. Os resultados sugerem que a hidrólise enzimática é menos eficiente na conversão total de amido no bagaço de mandioca. No entanto, o uso de ácido sulfúrico degradou até mesmo a parcela fibrosa do material, afetando as condições de análise.

12.
Braz. arch. biol. technol ; 52(3): 701-713, May-June 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-520922

RESUMO

Two commercial varieties of Peruvian carrot ('Amarela de Carandaí' and 'Senador Amaral') were processed into flour, starch and bagasse and chemically evaluated. The starch was extracted, modified with H2O2 and characterized by the physicochemical methods. By using the methylene blue dyeing, the granules of the modified starches showed intense blue color. The carboxyl content, the reducing power and the amount of the water liberated from the pastes after the freeze-thawing were higher for the oxidized starches and their pastes were clearer than those of the native starches of the two varieties from the two production areas. The RVA viscoamylography showed that the modified starches had lower viscosities with differences between the varieties. In the thermal analysis, the temperatures of the pyrolysis were higher for the native (310.37, 299.08, 311.18 ºC) than for the modified starches (294.16, 296.65 e 293.29 ºC) for both the varieties. This difference could be related with the larger surface of the granules due to the partial degradation promoted by the chemical modification. In almost all results, the differences were evident between the varieties but not for the cultivation places.


No presente trabalho duas variedades comerciais de mandioquinha-salsa ('Amarela de Carandaí' e 'Senador Amaral') obtidas dos municípios de Castro e de Piraí do Sul (Paraná) foram processadas para a obtenção de farinha, farelo e amido e essas três frações foram caracterizadas quimicamente. O amido foi extraído, modificado com H2O2 e caracterizado por meio de análises físico-químicas. Na coloração com azul de metileno os grânulos dos amidos oxidados apresentaram coloração azul mais intensa. O teor de carboxilas, o poder redutor e a quantidade de água liberada das pastas foram maiores para as amostras de amidos modificados. As pastas dos amidos modificados foram mais claras que as dos nativos. Na análise viscoamilográfica (RVA) os amidos modificados apresentaram as menores viscosidades e houve diferenças entre as variedades, sendo que o amido modificado da variedade Senador Amaral de Piraí do Sul apresentou os menores valores de pico de viscosidade. Na análise térmica, as temperaturas de pirólise foram mais altas para os amidos nativos das variedades da mandioquinha-salsa (310,37, 299,08, 311,18 ºC) do que para os amidos modificados (294,16, 296,65 e 293,29 ºC) e esta diferença pode estar relacionada a maior superfície dos grânulos de amido parcialmente degradados pela modificação oxidativa. Os resultados revelaram diferenças entre os amidos das duas variedades, mas não entre os locais de cultivo.

13.
Appl Biochem Biotechnol ; 157(1): 10-22, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19277490

RESUMO

This work aimed at investigating both the tolerance and the phytodegradation potential of Erythrina crista-galli L. in petroleum-contaminated soil. It consisted in analyzing E. crista-galli germination, surviving, growth, and development when cultivated at different contaminant concentrations and pollutant degradation rates. This specimen was selected because it presented a special behavior among others also exposed to petroleum in an accident that occurred in the Araucaria region (south of Brazil), resulting in a four-million-liter oil spill. The experiment was carried out in a greenhouse containing non-contaminated soil (NCS), vegetated contaminated soil (VCS), and non-vegetated contaminated soil (NVCS) at the following petroleum concentrations: 25 g kg(-1) (VCS-25), 50 g kg(-1) (VCS-50), and 75 g kg(-1) (VCS-75). After 60 days, the soil samples were analyzed by gas chromatography. Germination was more and more evident as higher petroleum concentrations were observed. The surviving rates of groups NCS, VCS-25, VCS-50, and VCS-75 were 64%, 70%, 61%, and 96%, respectively. The VCS group growth was reduced when compared to the control group (NCS). The individuals exposed to petroleum pollution presented differences in the anatomic structure of their roots when compared to the NCS group. It was observed that the petroleum degradation rate was higher for VCS group than for NVCS. E. crista-galli is potentially recommended for petroleum-contaminated soils because of its positive association in the presence of contamination.


Assuntos
Biodegradação Ambiental , Erythrina/metabolismo , Petróleo/metabolismo , Poluentes do Solo/metabolismo , Erythrina/crescimento & desenvolvimento , Resíduos Industriais , Petróleo/toxicidade , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Solo/análise , Poluentes do Solo/análise , Poluentes do Solo/isolamento & purificação
14.
Braz. arch. biol. technol ; 51(6): 1209-1215, Nov.-Dec. 2008. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-504043

RESUMO

Cassava starch, partially hydrolyzed by fungal á-amylase, was characterized using thermal analysis, light microscopy and X-ray diffraction. Thermal degradation was initiated at lower degradation temperatures after enzymatic treatment and the DSC (Differential scanning calorimetry) analysis showed almost similar range of gelatinization temperature, but the enthalpies of gelatinization were quite increased for the partially hydrolyzed starch granules. The results suggested that the partial degradation of the starch granules was concentrated in the amorphous regions.


Amilases fúngicas são comumente empregadas a amidos com o intuito de otimizar o rendimento de leveduras, modificar a textura de produtos panificados e prolongar a vida de prateleira do produto final. A hidrólise parcial enzimática pode auxiliar no entendimento da estrutura do amido ganular. Amido de mandioca parcialmente hidrolisado por á-amilase fúngica foi investigado utilizando-se técnicas termoanalíticas, microscopia ótica e difratometria por raios X. A degradação térmica iniciou-se a temperaturas menores após o tratamento enzimático e a análise por DSC mostrou uma próxima faixa de temperatura de gelatinização, porém, a entalpia necessária para o evento foi maior para os grânulos parcialmente hidrolisados. Os resultados sugerem que a degradação parcial do amido granular foi concentrada em regiões amorfas.

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