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1.
Curr Microbiol ; 78(12): 4014-4022, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34595548

RESUMO

Spirulina is a filamentous microalga which is considered a promising alternative source of essential nutrients and active biomolecules. High production cost and the space required to install a photobioreactor are two of the greatest challenges in the industrial application of microalga-based products. Thus, this study aimed to improve Spirulina sp. LEB 18 biomass and phycocyanin content by combining the application of mixotrophic culture and magnetic fields (MF). Zarrouk medium was modified with 1 and 3 g/L liquid molasses and the application of 30 mT for 1·h/d was investigated. Mixotrophic culture with 1 g/L molasses showed the highest biomass concentration (1.62 g/L), carbohydrate content (25.6%), and lipid contents (8.7%) after 15 days. Although the combination of 30 mT and 1 g/L liquid molasses decreased biomass production (1.44 g/L), there was increase in protein yield (76.9%) and protein productivity (73.8 mg/L·d). The proposed method increased phycocyanin production by 145% and its purity from 0.584 in the control culture to 0.627. Data described by this study show that the combination of mixotrophic culture and MF application is a promising alternative to increase microalga protein and phycocyanin production.


Assuntos
Spirulina , Biomassa , Carboidratos , Campos Magnéticos , Ficocianina
2.
J Food Sci Technol ; 58(5): 1663-1672, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33897005

RESUMO

In this research, the protein concentration, the permeate flux, and the predominant fouling mechanisms were investigated during ultrafiltration of different whey samples. The research was carried out at different values of transmembrane pressure and temperature using an experimental design, and a protein concentration of approximately 37 g L-1 was obtained for the bovine whey powder solution, at 60 kPa and 40 °C. The maximum flux observed was 8.9 and 7.9 kg m-2 h-1, respectively, for the bovine whey powder solution and bovine whey, at 50 kPa and 30 °C. Although goat and buffalo whey presented lower permeate flux, probably due to high solutes and calcium contents, protein concentrates of around 40 g L-1 were obtained using the ultrafiltration process. This demonstrates the potential of ultrafiltration to obtain non-bovine protein concentrates. The best fit, verified by Ho and Zydney model, suggests that the fouling for all analyzed whey occurs due to pore blocking and subsequent deposit on the membrane surface.

3.
Chem Phys Lipids ; 236: 105064, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33609502

RESUMO

This study describes the physicochemical properties of soybean asolectin (ASO) liposomes loaded with phycocyanin (Phy) extracted from Spirulina sp. LEB 18. The effects of Phy in the liposomes' properties were investigated by Fourier transform infrared spectroscopy (FTIR), 1H and 31P nuclear magnetic resonance (NMR), zeta (ζ)-potential, dynamic light scattering (DLS) and ultraviolet-visible (UV-vis) techniques. Phy restricted the motion of ASO polar and interface groups and disrupted the package arrangement of the lipid hydrophobic regions, as a likely effect of dipolar and π interactions related to its amino acid residues and pyrrole portions. These interactions were correlated to antiradical/antioxidant Phy responses obtained by 2,2-diphenyl-1-picrylhidrazil (DPPH) assay, thiobarbituric acid reactive substances (TBARS) and ferric reducing antioxidant power (FRAP) methods, and discussed to bring new chemical perspectives about Phy-loaded liposomes-related nutraceutical applications in inflammatory and viral infection processes.


Assuntos
Antioxidantes/farmacologia , Ficocianina/farmacologia , Spirulina/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Recuperação de Fluorescência Após Fotodegradação , Lipossomos/química , Ficocianina/química , Ficocianina/isolamento & purificação , Picratos/antagonistas & inibidores
4.
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
5.
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
6.
Ciênc. rural (Online) ; 50(1): e20190595, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1055856

RESUMO

ABSTRACT: There are no specific technical regulations regarding the identity and quality of white mold surface-ripened cheeses in Brazil. These cheeses are sold both whole (Camembert-type) and in wedges (Brie-type). The aim of the study was to evaluate the physical and chemical properties; technological parameters and microbiological safety of 20 whole cheeses (Camembert-type) and 16 cheese wedges (Brie-type) produced in Brazil. Samples showed a wide range in sodium (91.0-731.0 mg/100 g, cheeses wedges) and calcium (238.0-1100.0 mg/100g, whole cheeses) contents. The cheese groups presented no significant differences in relation to the majority of the analyzed parameters. Listeria monocytogenes was reported in 5% of the whole cheese samples. The other microbiological parameters were in accordance with the current legislation, RDC no 12/2001 of Anvisa. The comparative assessments between these two cheeses indicated that they are different. In addition, the wide range of results indicated a lack of processing standardization. The mean values of the physicochemical and textural parameters should be considered as recommended for these cheeses in Brazil.


RESUMO: No Brasil, não há uma regulamentação técnica específica sobre a identidade e qualidade de queijos maturados com mofo branco na superfície. Estes queijos são comercializados inteiros (tipo Camembert) e em cunhas (tipo Brie). O objetivo da pesquisa foi avaliar as propriedades físicas e químicas; parâmetros tecnológicos e marcadores microbiológicos de 20 queijos inteiros (tipo Camembert) e 16 cunhas de queijo (tipo Brie) produzidos no Brasil. Os teores de sódio e cálcio apresentaram elevada amplitude (8,0 e 4,6 vezes o valor mínimo, respectivamente). Os valores médios destes queijos não apresentaram diferenças significativas em relação à maioria dos parâmetros analisados. Listeria monocytogenes foi encontrada em 5% das amostras de queijo tipo Camembert. Os demais parâmetros microbiológicos estavam de acordo com a legislação vigente, RDC no 12/2001 da Anvisa. Esta avaliação comparativa entre estes dois queijos indica que são diferentes. Além disso, os valores com elevada amplitude correspondem a falta de padronização do processamento. Os valores médios poderiam ser considerados como recomendados para estes queijos no Brasil.

7.
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
8.
J Sci Food Agric ; 99(6): 2786-2792, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30430576

RESUMO

BACKGROUND: Freeze concentration is an alternative process where bioactive compounds are preserved during the processing of juice concentrates. This study proposed a simple and cheaper cryoconcentration process assisted by centrifugation in apple juice. RESULTS: The levels of phenolics increased significantly (P < 0.05) with each freeze concentration cycle that was performed. Furthermore, the process resulted in an average increase in the concentration of phenolics of 1.9, 2.9 and 3.8 times for the first, second and third steps of the concentration, respectively. In relation to phenolics, the antioxidant potential, which was evaluated by radical scavenging activity and reduction power, also increased with the cryoconcentration steps. The influence of the phenolics on the in vitro antioxidant activity was confirmed by a significant correlation between the antioxidant assays and total phenolics, flavonoids, flavan-3-ols, and flavonols (r > 0.70). CONCLUSION: The increase in antioxidant activity may have been attributed to the increase in the phenolic compounds in the apple juices because of the cryoconcentration process. Therefore, this could be an excellent natural product to supplement and enrich blends, juices, ciders, smoothies, and jams in order to improve the sensorial, nutritional and antioxidant properties. © 2018 Society of Chemical Industry.


Assuntos
Criopreservação , Sucos de Frutas e Vegetais/análise , Malus/química , Fenóis/química
9.
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
10.
J Food Sci Technol ; 55(8): 3035-3045, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30065413

RESUMO

The objective of this study was to develop a formulation that can retard staling/retrogradation of cheese breads without compromising their texture and expansion properties. During baking the dough expands and becomes soft, with lower density. Binary mixtures of cassava starch (Native + Oxidized) and with guar gum (Oxidized + Guar Gum) as well as a ternary mixture (Native + Oxidized + Guar Gum) were prepared. The mixtures were analyzed for freeze-thaw stability, expansion, pasting, thermal structural and retrogradation properties. The results were compared with those of sour cassava starch (polvilho azedo-PA), native cassava starch (N) and oxidized cassava starch (O). Moreover, cheese breads were prepared with these mixtures and evaluated during storage. The ternary mixture N + O + GG showed superior freeze-thaw stability (syneresis of 4.9, 7.8 and 11.0% in 1st, 2nd and 3rd cycles, respectively); the low retrogradation of this sample was confirmed both by DSC and FTIR analyses. The sample N + O + GG had a high expansion (> 10 mL/g) and the cheese breads developed with this mixture had a slower staling. Our results confirmed that the mixture N + O + GG can improve formulations of gluten-free baked foods.

11.
Ciênc. rural (Online) ; 48(5): e20170886, 2018. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1045125

RESUMO

ABSTRACT: This study aimed to know the biodiversity of non-Saccharomyces yeasts in Brazilian apples must with potential to improve of the aromatic quality of ciders. The strains were isolated from thirty-five (35) Gala and Fuji apple musts from different locations from south region of Brazil. Forty-five (45) strains were isolate and identified by PCR analysis. Results indicated ten (10) species: Candida oleophila, Candida parapsilosis, Candida tropicalis, Clavispora lusitaniae, Hanseniaspora guilliermondii, Hanseniaspora uvarum, Lodderomyces elongisporus, Pichia anomala, Pichia fermentans and Rhodotorula mucilaginosa. The genus Rhodotorula sp., Lodderomyces sp. and Clavispora sp. constituted 71.2% of the strains identified. The following strains, C. oleophila, R. mucilaginosa, P. fermentans, H. uvarum and H. guilliermondii were selected in qualitative tests due the fruity aroma production by trained team in the aromatic assessment of cider.


RESUMO: Este estudo teve como objetivo conhecer a biodiversidade de leveduras não-Saccharomyces em maçãs com potencial para a melhoria da qualidade aromática da sidra brasileira. As cepas foram isoladas de trinta e cinco (35) mostos de maçã Gala e Fuji de diferentes locais da região Sul do Brasil. Quarenta e cinco (45) cepas foram isoladas e identificadas por análise de PCR. Os resultados indicaram dez (10) espécies: Candida oleophila, Candida parapsilosis, Candida tropicalis, Clavispora lusitaniae, Hanseniaspora guilliermondii, Hanseniaspora uvarum, Lodderomyces elongisporus, Pichia anomala, Pichia fermentans e Rhodotorula mucilaginosa. Três desses gêneros (Rhodotorula sp., Lodderomyces sp. e Clavispora sp.) juntos constituíram 71,2% das cepas identificadas. Entre estas cepas, C. oleophila, R. mucilaginosa, P. fermentans, H. uvarum e H. guilliermondii foram selecionadas em teste qualitativo devido a produção de aroma frutado, indicando potencial para a produção de compostos aromáticos na sidra.

12.
J Food Sci Technol ; 54(6): 1511-1518, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28559610

RESUMO

The effect of variety and ripening stage on the distribution of phenolic compounds and in vitro antioxidant capacity of Gala, Fuji Suprema and Eva apples were evaluated. Hydroxycinnamic acids, flavonoids, flavanols, flavonols, dihydrochalcones and antioxidant activity (FRAP and DPPH) were assessed in the epicarp, mesocarp and endocarp of three varieties at three ripening stages (unripe, ripe and senescent). The Fuji Suprema variety distinguished by its content of flavonols at senescent stage, while Eva variety distinguished by its content of dihydrochalcones (unripe stage) and anthocyanins (ripe stage). In general, phenolic acids and flavonoids decreased with ripening in the epicarp and endocarp. However, in the mesocarp, the effect of ripening was related with the apple variety. Hierarchical cluster analysis confirmed the influence of ripening in the apple tissue. The evolution of these compounds during ripening occurred irregularly and it was influenced by the variety.

13.
Ciênc. rural (Online) ; 47(10): e20161042, 2017. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1044862

RESUMO

ABSTRACT: One of the most crucial steps in cheesemaking is the coagulation process, and knowledge of the parameters involved in the clotting process plays an important technological role in the dairy industry. Milk of different ruminant species vary in terms of their coagulation capacities because they are influenced by the milk composition and mainly by the milk protein genetic variants. The milk coagulation capacity can be measured by means of mechanical and/or optical devices, such as Lactodynamographic Analysis and Near-Infrared and Mid-Infrared Spectroscopy.


RESUMO: Uma das etapas mais importantes na fabricação de queijos é o processo de coagulação. O conhecimento dos parâmetros envolvidos nesse processo desempenha um papel tecnológico importante para a indústria de laticínios. O leite de diferentes espécies de ruminantes varia em termos de capacidade de coagulação, pois são influenciados pela composição e principalmente pelas variantes genéticas da caseína. Estas características podem ser avaliadas por meio de dispositivos mecânicos e/ou ópticos, tais como, a Análise Lactodinamográfica e a Espectroscopia de Reflectância do Visível ao Infravermelho Próximo (NIR) e Médio (MIR).

14.
J Sci Food Agric ; 96(11): 3831-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26692071

RESUMO

BACKGROUND: White mold-ripened cheeses were investigated with the objective of proposing a colorimetric method to monitor the surface growth of Penicillium candidum and to evaluate the influence of the mesophilic (homofermentative (QMO) and heterofermentative (QMLD)) and thermophilic (QT) starter cultures on the physicochemical composition and sensory description. RESULTS: The whiteness index was effective in proving the appearance of superficial mycelium and the stability of white mold growth. The lactic cultures showed significant influence on most of the physicochemical analyses. The cheese made with thermophilic lactic culture had a 1 day gain in the growth of mycelium on the surface; nevertheless, the appearance of this product was potentially not acceptable for consumers. The heterofermentative mesophilic cheese had a better appearance and texture profile. However, the homofermentative mesophilic cheese showed aspects of fresh cheese and was acceptable for a wide range of consumers. CONCLUSION: The whiteness index was efficient to monitor the surface growth of P. candidum. The highest proteolytic effect was found in the QMLD and QT cultures. However, the cheese elaborated with the QMLD culture showed the best sensory acceptance. © 2015 Society of Chemical Industry.


Assuntos
Queijo/análise , Inspeção de Alimentos , Qualidade dos Alimentos , Lactobacillus delbrueckii/crescimento & desenvolvimento , Lactococcus lactis/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Streptococcus thermophilus/crescimento & desenvolvimento , Brasil , Queijo/microbiologia , Fenômenos Químicos , Fermentação , Preferências Alimentares , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus delbrueckii/metabolismo , Lactococcus lactis/metabolismo , Fenômenos Mecânicos , Proteínas do Leite/análise , Proteínas do Leite/metabolismo , Penicillium/metabolismo , Análise de Componente Principal , Proteólise , Sensação , Streptococcus thermophilus/metabolismo , Propriedades de Superfície , Tirosina/análise , Tirosina/metabolismo
15.
J Food Sci ; 80(9): S2045-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26259705

RESUMO

This study aimed to establish a manufacturing protocol and to characterize semihard cheese covered with lard and rosemary during ripening. After the manufacturing protocol was defined, the cheeses were produced with pasteurized and raw milk from Holstein cows, with and without (control) coating, and then ripened for 60 d. During this period the physicochemical properties, color, proteolysis, texture profile, and sensory acceptance were performed. The early-ripening cheeses differed from the others in terms of color and moisture content. Multivariate statistical analysis separated chesses in groups differentiated by the effects of heat treatment of milk and ripening period. The ripened cheeses obtained from raw milk were sensorially more preferred. The coating gave the final products higher moisture content and favored color and texture characteristics. Consumer testing showed that the cheese obtained from raw milk and coated with lard and rosemary was the most preferred (acceptance of 82%) due to the specific coating of rosemary (aroma and flavor). This product has potential to add value and to diversify the production of semihard cheeses.


Assuntos
Queijo/análise , Gorduras na Dieta , Leite , Odorantes , Pasteurização , Rosmarinus , Paladar , Animais , Bovinos , Queijo/normas , Cor , Comportamento do Consumidor , Feminino , Temperatura Alta , Humanos , Folhas de Planta , Especiarias , Água
16.
Yeast ; 32(8): 559-65, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26095929

RESUMO

Hanseniaspora yeasts are known to produce volatile compounds that give fruity aromas in wine and fermented fruit. This study aimed to verify the feasibility of the Hanseniaspora uvarum strain that had been isolated and identified during a previous study and preserved by lyophilization and freezing at -80 °C (cryopreservation). This strain was assessed in relation to its macroscopic and microscopic morphology and for its ability to ferment apple must. After having been subjected to lyophilization and cryopreservation, viability was assessed in relation to these characteristics during 12 months of storage. The strain showed stable colonial features and its microscopic appearance was unchanged during all recoveries. The plate count results showed consistency in both processes. Regarding the fermentative capacity, the kinetic results showed 100% viability for the strain subjected to lyophilization, as well as for those preserved at -80 °C. These results demonstrate that the preservation methods used are compatible with the maintenance of the relevant characteristics of the strain for the period of evaluation of this study (12 months).


Assuntos
Hanseniaspora/química , Viabilidade Microbiana , Criopreservação , Fermentação , Liofilização , Hanseniaspora/crescimento & desenvolvimento , Hanseniaspora/metabolismo , Malus/metabolismo , Malus/microbiologia
17.
J Food Sci Technol ; 52(4): 2083-92, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25829588

RESUMO

Acid whey is a by-product from cheese processing that can be employed in beverage formulations due to its high nutritional quality. The objective of the present work was to study the physicochemical characterisation of acid whey from Petit Suisse-type cheese production and use this by-product in the formulation of fermented milk, substituting water. In addition, a reduction in the fermentation period was tested. Both the final product and the acid whey were analysed considering physicochemical determinations, and the fermented milk was evaluated by means of sensory analysis, including multiple comparison and acceptance tests, as well as purchase intention. The results of the physicochemical analyses showed that whey which was produced during both winter and summer presented higher values of protein (1.22 and 0.97 %, w/v, respectively), but there were no differences in lactose content. During the autumn, the highest solid extract was found in whey (6.00 %, w/v), with larger amounts of lactose (4.73 %, w/v) and ash (0.83 %, w/v). When analysing the fermented milk produced with added acid whey, the acceptance test resulted in 90 % of acceptance; the purchase intention showed that 54 % of the consumers would 'certainly buy' and 38 % would 'probably buy' the product. Using acid whey in a fermented milk formulation was technically viable, allowing by-product value aggregation, avoiding discharge, lowering water consumption and shortening the fermentation period.

18.
J Food Sci ; 80(6): C1170-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25920613

RESUMO

The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (<75 mg/L) nitrogen content, and four enological yeast strains, were used in cider fermentation. The aspartic acid, asparagine and glutamic acid amino acids were the majority in all the apple juices, representing 57.10% to 81.95%. These three amino acids provided a high consumption (>90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3-methyl-1-butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation.


Assuntos
Bebidas Alcoólicas/análise , Aminoácidos/metabolismo , Fermentação , Frutas/química , Malus/química , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/análise , Álcoois/metabolismo , Ésteres/metabolismo , Humanos , Nitrogênio/metabolismo , Pentanóis/metabolismo
19.
Ciênc. rural ; 45(4): 744-749, 04/2015. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-742811

RESUMO

Fruits from temperate and tropical climates which have high levels of antioxidant compounds are the source of numerous studies concerning the correlation with benefits to human health. The objectives of this study were to quantify the anthocyanins and phenolic compounds and also to measure the antioxidant activity (ferric reducing antioxidant power - FRAP) of blackberries from two varieties grown in southern Brazil ('Brazos' and 'Tupy') at three stages of ripening; unripe, semi-ripe, ripe and their products (pulp and fermented products). During fruit ripening it was observed that weight, size, diameter and sugars increase significantly and acidity decreased significantly. The anthocyanin content ranged from 4.19 (semi-ripe 'Tupy' variety) to 205.75mg 100g-1 (ripe 'Brazos' variety). The highest levels of phenolic compounds were observed for the unripe fruit of both varieties, while antioxidant activity showed no significant difference during the ripening stages. The studied pulp showed a high content of phenolic compounds (ten times higher than that found in the ripe fruits). The anthocyanin content and antioxidant activity did not show the same increase due to the degradation of anthocyanins caused by the heat treatment that was used. The alcoholic fermented beverage made from blackberries remained stable (total phenolic compounds and antioxidant activity) during two years of storage, but the in third year a significant reduction in antioxidant activity was observed. These results can be important for establishing the shelf life of this kind of product made with blackberry.


Algumas frutas de clima temperado e tropical, principalmente as do tipo "berries", têm como característica o acúmulo de compostos antioxidantes e são objeto de inúmeros estudos, haja vista a sua correlação com os benefícios para a saúde humana. Os objetivos deste trabalho foram quantificar as antocianinas, os compostos fenólicos e mensurar a capacidade antioxidante (ferric reducing antioxidant power - FRAP) de amoras-pretas de duas cultivares ('Brazos' e 'Tupy'), nos três estágios de maturação, considerados verde, semi-maduro e maduro, e dos seus produtos (polpas e fermentados). No processo de maturação da fruta, observou-se que o peso, tamanho, diâmetro e teor de açúcar aumentaram significativamente enquanto a acidez diminuiu. Os teores de antocianinas aumentaram de 4,19 (FSM cv. 'Tupy') (frutos semi-maduros) para 205,75mg 100g-1 (FM cv. 'Brazos') (frutos maduros). Os maiores teores de compostos fenólicos foram verificados para os frutos verdes (FV) das duas cultivares, enquanto a atividade antioxidante não apresentou diferença significativa nos estádios de maturação. A polpa estudada acumulou um elevado teor de compostos fenólicos (dez vezes superior ao encontrado nas frutas maduras). Os teores de antocianinas e de atividade antioxidante não apresentaram o mesmo perfil em função da degradação das antocianinas pelo processo térmico utilizado. O fermentado alcoólico de amora permaneceu estável (fenóis totais e atividade antioxidante) durante dois anos de estocagem, porém, no terceiro ano, foi observada uma redução significativa da atividade antioxidante. Estes resultados são importantes para o estabelecimento da vida-de-prateleira desses produtos derivados da amora.

20.
J Food Sci ; 79(4): C510-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24547813

RESUMO

A total of 19 Brazilian frozen pulps from the following fruits: açai (Euterpe oleracea), blackberry (Rubus sp.), cajá (Spondias mombin), cashew (Anacardium occidentale), cocoa (Theobroma cacao), coconut (Cocos nucifera), grape (Vitis sp.), graviola (Annona muricata), guava (Psidium guajava), papaya (Carica papaya), peach (Prunus persica), pineapple (Ananas comosus), pineapple and mint (A. comosus and Mentha spicata), red fruits (Rubus sp. and Fragaria sp.), seriguela (Spondias purpurea), strawberry (Fragaria sp.), tamarind (Tamarindus indica), umbu (Spondias tuberosa), and yellow passion fruit (Passiflora edulis) were analyzed in terms of chromaticity, phenolic compounds, carotenoids, and in vitro antioxidant activity using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. Data were processed using principal component analysis (PCA) and hierarchical cluster analysis (HCA). Antioxidant capacity was measured by DPPH and FRAP assays, which showed significant (P < 0.01) correlation with total phenolic compounds (r = 0.88 and 0.70, respectively), total flavonoids (r = 0.63 and 0.81, respectively), and total monomeric anthocyanins (r = 0.59 and 0.73, respectively). PCA explained 74.82% of total variance of data, and the separation into 3 groups in a scatter plot was verified. Three clusters also suggested by HCA, corroborated with PCA, in which cluster 3 was formed by strawberry, red fruits, blackberry, açaí, and grape pulps. This cluster showed the highest contents of total phenolic compounds, total flavonoids, and antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Cor , Flavonoides/farmacologia , Frutas/química , Fenóis/farmacologia , Plantas Comestíveis/química , Antocianinas/análise , Antocianinas/farmacologia , Antioxidantes/análise , Compostos de Bifenilo/metabolismo , Brasil , Carotenoides/análise , Flavonoides/análise , Congelamento , Humanos , Técnicas In Vitro , Oxirredução , Fenóis/análise , Picratos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia
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