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1.
Molecules ; 29(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38930808

RESUMO

In this study, a beverage made from a combination of Agave sap (AS) and prickly pear juice (PPJ) was analyzed for its nutrients and bioactive and potentially health-promoting compounds. The beverage was evaluated for its ability to act as an antioxidant, regulate glycemic properties, and undergo gut bacterial fermentation in vitro. The major mono- and oligosaccharides present in the beverage were galacturonic acid (217.74 ± 13.46 mg/100 mL), rhamnose (227.00 ± 1.58 mg/100 mL), and fructose (158.16 ± 8.86 mg/mL). The main phenolic compounds identified were protocatechuic acid (440.31 ± 3.06 mg/100 mL) and catechin (359.72 ± 7.56 mg/100 mL). It was observed that the beverage had a low glycemic index (<40) and could inhibit digestive carbohydrases. The combination of ingredients also helped to reduce gas production during AS fermentation from 56.77 cm3 to 15.67 cm3. The major SCFAs produced during fermentation were butyrate, acetate, and propionate, with valerate being produced only during the late fermentation of the AS. This beverage is rich in bioactive compounds, such as polyphenols and dietary fiber, which will bring health benefits when consumed.


Assuntos
Agave , Antioxidantes , Sucos de Frutas e Vegetais , Agave/química , Sucos de Frutas e Vegetais/análise , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/análise , Fermentação , Hidroxibenzoatos/análise , Polifenóis/análise , Polifenóis/química , Pyrus/química , Fenóis/análise , Fenóis/química , Ramnose/análise , Ramnose/química , Catequina/análise , Catequina/química , Catequina/análogos & derivados , Ácidos Hexurônicos
2.
Hig. Aliment. (Online) ; 33(288/289): 520-524, abr.-maio 2019. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1481988

RESUMO

O objetivo do estudo foi realizar a desidratação de amostras de pera através da secagem solar e obter as respectivas curvas de secagem. As amostras foram submetidas à desidratação em dois tipos de geometrias, circulares com 1cm de espessura e em cubos com 1cm de comprimento. Os dados experimentais das curvas de secagem para as duas condições foram ajustados ao modelo matemático de secagem baseado na Segunda Lei de Fick. Os resultados mostram que a umidade do fruto é de aproximadamente 85%. As amostras apresentaram peso constante a partir de 18 horas de experimento para a geometria plana e a partir de 30 horas para a geometria cilíndrica. O coeficiente difusivo, obtido através da aplicação da Segunda Lei de Fick, para geometria plana foi de 6,4 x 10(-4)m2/s e para a geometria cilíndrica de 3,35 x 10(-4) m2/s.


Assuntos
Conservação de Alimentos/estatística & dados numéricos , Conservação de Alimentos/métodos , Pyrus/efeitos da radiação , Pyrus/química , Cinética
3.
Hig. aliment ; 33(288/289): 520-524, abr.-maio 2019. ilus
Artigo em Português | VETINDEX | ID: vti-21942

RESUMO

O objetivo do estudo foi realizar a desidratação de amostras de pera através da secagem solar e obter as respectivas curvas de secagem. As amostras foram submetidas à desidratação em dois tipos de geometrias, circulares com 1cm de espessura e em cubos com 1cm de comprimento. Os dados experimentais das curvas de secagem para as duas condições foram ajustados ao modelo matemático de secagem baseado na Segunda Lei de Fick. Os resultados mostram que a umidade do fruto é de aproximadamente 85%. As amostras apresentaram peso constante a partir de 18 horas de experimento para a geometria plana e a partir de 30 horas para a geometria cilíndrica. O coeficiente difusivo, obtido através da aplicação da Segunda Lei de Fick, para geometria plana foi de 6,4 x 10(-4)m2/s e para a geometria cilíndrica de 3,35 x 10(-4) m2/s.(AU)


Assuntos
Conservação de Alimentos/estatística & dados numéricos , Conservação de Alimentos/métodos , Pyrus/química , Pyrus/efeitos da radiação , Cinética
4.
Ci. Rural ; 47(11): e20170331, nov. 2017. tab
Artigo em Inglês | VETINDEX | ID: vti-22571

RESUMO

The aim of this study was to characterize five different hybrid cultivars pears (‘Tenra, ‘Centenária, ‘Cascatence, ‘Primorosa and ‘Seleta) deployed in subtropical regions of Brazil regarding its physicochemical characteristics, bioactive compounds and antioxidant activity, as well as to evaluate the influence of these cultivars on the characteristics physicochemical, rheological properties and sensory acceptance of the obtained jelly, for identifying varieties with higher potential for industrial use. Regardingthe bioactive compounds and antioxidant activity it was observed that ‘Seleta cultivar was characterized by a higher phenolic content (57.68mg GAEs 100g-1), higher antioxidant activity (13.56% of DPPH sequestration and 1.25μM of trolox g -1) and higher content of vitamin C (3.59mg 100g-1). As the acidity, it ranged from 4.09 to 5.81 g of malic acid 100g-1 (‘Tenra and ‘Seleta, respectively). Regarding color, the color parameter L* varied from 32.14 to 36.83, a* ranged from 2.87 to 5.20, b* ranged from 16.57 to 20.42, Chroma ranged from 16.67 to 21.02 and °Hue ranged from 74.94 to 80.18. Regarding the texture, the jellies produced from ‘Centenária and ‘Tenra were characterized by having the highest values of hardness (1.21 and 1.23N, respectively), gumminess (0.42 and 0.45, respectively) and chewiness (0.40 and 0.45N, respectively). The jelly obtained from the ‘Centenária still showed the highest adhesiveness (2.27N s-1) and springiness (0.99). Already jellies prepared by ‘Cascatence showed the highest cohesiveness values (0.68). The jellies prepared with different pear cultivars showed good sensory acceptance for all measured properties, with average scores ranging between the hedonic terms “liked slightly” to “liked very much”. Cultivars of subtropical pear trees present different physicochemical characteristics, resulting in jellies with different physicochemical characteristics and rheological properties...(AU)


O objetivo deste estudo foi caracterizar cinco diferentes cultivares híbridas de peras (‘Tenra, ‘Centenária, ‘Cascatence, ‘Primorosa e ‘Seleta) implantadas em regiões subtropicais do Brasil quanto as caracteristicas físico-química, compostos bioativos e atividade antioxidante, bem como avaliar a influência destas cultivares sobre as características físico-químicas, propriedades reológicas e aceitação sensorial da geleia obtida, para identificação de cultivares com maior potencial para a utilização industrial. Com relação aos compostos bioativos e atividade antioxidante, pode-se observar que a cultivar ‘Seleta caracterizou-se pelo maior teor de fenólicos (57,68mg GAEs 100 g-1), maior atividade antioxidante (13,56% de sequestro de DPPH e 1,25μM de trolox g-1) e se destaca devido ao seu maior teor de vitamina C (3,59mg 100g-1). A acidez, variou de 4,09 a 5,81g de ácido málico 100 g-1 (‘Tenra e ‘Seleta, respectivamente). Em relação à cor, o parâmetro de cor L* variou de 32,14 a 36,83, a* variou de 2,87 a 5,20, b* variou de 16,67 a 20,42, Chroma variou de 16,57 a 21,02 e °Hue variou de 74,94 a 80,18. Em relação à textura, as geleias produzidas a partir de ‘Centenária e ‘Tenra caracterizam-se por apresentar os maiores valores de dureza (1,21 e 1,23N, respectivamente), gomosidade (0,42 e 0,45N, respectivamente) e mastigabilidade (0,40 e 0,45, respectivamente). A geleia obtida da ‘Centenária ainda apresentava a maior adesividade (2,27N s-1) e a elasticidade (0,99). Já as geleias preparadas com a ‘Cascatence apresentaram os maiores valores de coesividade (0,68). As geleias preparadas com diferentes cultivares de pera mostraram boa aceitação sensorial para todas as propriedades avaliadas, com notas médias variando entre os termos hedônicos “gostei ligeiramente” e “gostei muito”...(AU)


Assuntos
Pyrus/química , Pyrus/fisiologia , Manipulação de Alimentos , Sensação
5.
J AOAC Int ; 99(6): 1426-1435, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27642168

RESUMO

Most of the analytical methods currently applied in food control laboratories are focused on the determination of target compounds using LC coupled to tandem MS, which is an effective technique, but low-resolution MS is limited. Thus, a method for determination of pesticide multiresidues in fruits (pear, apple, and grape) using a modified quick, easy, cheap, effective, rugged, and safe method and LC coupled to quadrupole time-of-flight (Q-TOF) MS was developed and validated. The proposed method showed good linearity (r2 > 0.99) from 1 to 100 µg/L. Recoveries for blank samples spiked at 0.01, 0.04, and 0.10 mg/kg were between 66 and 122%, with RSDs <28%. Respective LOQs for apple, pear, and grape matrixes were 0.01 mg/kg for 112, 120, and 118 compounds, and 0.04 mg/kg for 22, 12, and 17 compounds, and average mass accuracy error was 3.2 ppm. LC with Q-TOF MS detection using protonated molecular ion and/or adducts and mass accuracy provided reliability for the method. The proposed method is effective for pesticide residue determination in apple, pear, and grape samples, proving that high-resolution MS using full scan mode can be a powerful and reliable technique for quantification purposes, being adequate for application in the surveillance of maximum residue limits set by different legislations.


Assuntos
Contaminação de Alimentos/análise , Malus/química , Resíduos de Praguicidas/análise , Pyrus/química , Vitis/química , Cromatografia Líquida , Espectrometria de Massas
6.
Molecules ; 21(1): 92, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26784158

RESUMO

A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 ± 0.65 µg/mL, 712.63 ± 12.12 micromols trolox equivalents (µmol/TE)/100 g FW, and 82.89% ± 2.52% at 100 µg/mL, respectively).


Assuntos
Antioxidantes/isolamento & purificação , Flavonoides/isolamento & purificação , Frutas/química , Fenóis/isolamento & purificação , Pyrus/química , Quercetina/análogos & derivados , Antioxidantes/química , Antioxidantes/metabolismo , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Chile , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Clima Desértico , Flavonoides/biossíntese , Flavonoides/química , Fenóis/química , Fenóis/metabolismo , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Pyrus/metabolismo , Quercetina/biossíntese , Quercetina/química , Quercetina/isolamento & purificação , Superóxidos/antagonistas & inibidores , Superóxidos/química , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
7.
Biol Res ; 47: 71, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25723734

RESUMO

BACKGROUND: Rootstocks play an essential role to determining orchard performance of fruit trees. Pyrus communis and Cydonia oblonga are widely used rootstocks for European pear cultivars. The lack of rootstocks adapted to different soil conditions and different grafted cultivars is widely acknowledged in pear culture. Cydonia rootstocks (clonal) and Pyrus rootstocks (seedling or clonal) have their advantages and disadvantages. In each case, site-specific environmental characteristics, specific cultivar response and production objectives must be considered before choosing the best rootstock. In this study, the influence of three Quince (BA 29, Quince A = MA, Quince C = MC) and a local European pear seedling rootstocks on the scion yield, some fruit quality characteristics and leaf macro (N, P, K, Ca and Mg) and micro element (Fe, Zn, Cu, Mn and B) content of 'Santa Maria' pear (Pyrus communis L.) were investigated. RESULTS: Trees on seedling rootstock had the highest annual yield, highest cumulative yield (kg tree(-1)), largest trunk cross-sectional area (TCSA), lowest yield efficiency and lowest cumulative yield (ton ha(-1)) in the 10(th) year after planting. The rootstocks had no significant effect on average fruit weight and fruit volume. Significantly higher fruit firmness was obtained on BA 29 and Quince A. The effect of rootstocks on the mineral element accumulation (N, K, Ca, Mg, Fe, Zn, Cu, Mn and B) was significant. Leaf analysis showed that rootstocks used had different mineral uptake efficiencies throughout the early season. CONCLUSION: The results showed that the rootstocks strongly affected fruit yield, fruit quality and leaf mineral element uptake of 'Santa Maria' pear cultivar. Pear seedling and BA 29 rootstock found to be more prominent in terms of several characteristics for 'Santa Maria' pear cultivar that is grown in highly calcareous soil in semi-arid climate conditions. We determined the highest N, P (although insignificant), K, Ca, Mg, Fe and Cu mineral element concentrations on the pear seedling and BA 29 rootstocks. According to the results, we recommend the seedling rootstock for normal density plantings (400 trees ha(-1)) and BA 29 rootstock for high-density plantings (800 trees ha(-1)) for 'Santa Maria' pear cultivar in semi-arid conditions.


Assuntos
Produção Agrícola/métodos , Clima Desértico , Frutas/metabolismo , Folhas de Planta/química , Raízes de Plantas/metabolismo , Pyrus , Boro/análise , Cálcio/análise , Cobre/análise , Ferro/análise , Magnésio/análise , Manganês/análise , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Pyrus/química , Pyrus/classificação , Pyrus/crescimento & desenvolvimento , Chuva , Rosaceae/fisiologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Solo , Temperatura , Turquia , Zinco/análise
8.
Biol. Res ; 47: 1-8, 2014. graf, tab
Artigo em Inglês | LILACS | ID: biblio-950767

RESUMO

BACKGROUND: Rootstocks play an essential role to determining orchard performance of fruit trees. Pyrus communisand Cydonia oblonga are widely used rootstocks for European pear cultivars. The lack of rootstocks adapted to different soil conditions and different grafted cultivars is widely acknowledged in pear culture. Cydonia rootstocks (clonal) and Pyrus rootstocks (seedling or clonal) have their advantages and disadvantages. In each case, site-specific environmental characteristics, specific cultivar response and production objectives must be considered before choosing the best rootstock. In this study, the influence of three Quince (BA 29, Quince A = MA, Quince C = MC) and a local European pear seedling rootstocks on the scion yield, some fruit quality characteristics and leaf macro (N, P, K, Ca and Mg) and micro element (Fe, Zn, Cu, Mn and B) content of 'Santa Maria' pear (Pyrus communis L.) were investigated. RESULTS: Trees on seedling rootstock had the highest annual yield, highest cumulative yield (kg tree(-1)), largest trunk cross-sectional area (TCSA), lowest yield efficiency and lowest cumulative yield (ton ha(-1)) in the 10th year after planting. The rootstocks had no significant effect on average fruit weight and fruit volume. Significantly higher fruit firmness was obtained on BA 29 and Quince A. The effect of rootstocks on the mineral element accumulation (N, K, Ca, Mg, Fe, Zn, Cu, Mn and B) was significant. Leaf analysis showed that rootstocks used had different mineral uptake efficiencies throughout the early season. CONCLUSION: The results showed that the rootstocks strongly affected fruit yield, fruit quality and leaf mineral element uptake of 'Santa Maria' pear cultivar. Pear seedling and BA 29 rootstock found to be more prominent in terms of several characteristics for 'Santa Maria' pear cultivar that is grown in highly calcareous soil in semi-arid climate conditions. We determined the highest N, P (although insignificant), K, Ca, Mg, Fe and Cu mineral element concentrations on the pear seedling and BA 29 rootstocks. According to the results, we recommend the seedling rootstock for normal density plantings (400 trees ha(-1)) and BA 29 rootstock for high-density plantings (800 trees ha(-1)) for 'Santa Maria' pear cultivar in semi-arid conditions.


Assuntos
Raízes de Plantas/metabolismo , Folhas de Planta/química , Pyrus/classificação , Pyrus/crescimento & desenvolvimento , Pyrus/química , Clima Desértico , Produção Agrícola/métodos , Frutas/metabolismo , Fósforo/análise , Potássio/análise , Chuva , Solo , Temperatura , Turquia , Zinco/análise , Boro/análise , Cálcio/análise , Cobre/análise , Rosaceae/fisiologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Ferro/análise , Magnésio/análise , Manganês/análise , Nitrogênio/análise
9.
An Acad Bras Cienc ; 84(3): 853-63, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22886168

RESUMO

Recently, non-destructive techniques such as the Vis / NIR spectroscopy have been used to evaluate the characteristics of maturation and quality of pears. The study aims to validate the readings by the Vis / NIR spectroscopy as a non-destructive way to assess the qualitative characteristics of pear cultivars 'Williams', 'Packams' and 'Carrick', produced according to Brazilian conditions. The experiment was conducted at the Pelotas Federal University, UFPel, in Pelotas / RS, and the instrument used to measure the fruit quality in a non-destructive way was the NIR- Case spectrophotometer (SACMI, Imola, Italy). To determine pears' soluble solids (SS) and pulp firmness (PF), it was established calibration equations for each variety studied, done from the evaluations obtained by a non-destructive method (NIR-Case) and a destructive method. Further on, it was tested the performance of these readings by linear regressions. The results were significant for the soluble solids parameter obtained by the Vis / NIR spectroscopy; however, it did not achieve satisfactory results for the pear pulp firmness of these cultivars. It is concluded that the Vis / NIR spectroscopy, using linear regression, allows providing reliable estimates of pears' quality levels, especially for soluble solids.


Assuntos
Qualidade dos Alimentos , Frutas/normas , Pyrus/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Frutas/química , Reprodutibilidade dos Testes
10.
J Agric Food Chem ; 59(22): 12155-62, 2011 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-21980919

RESUMO

Preharvest conditions can have a great impact on fruit quality attributes and postharvest responses. Firmness is an important quality attribute in pear, and excessive softening increases susceptibility to bruising and decay, thus limiting fruit postharvest life. Textural characteristics of fruits are determined at least in part by cell wall structure and disassembly. Few studies have analyzed the influence of fruit preharvest environment in softening, cell wall composition, and degradation. In the current work 'Bartlett' pears grown either facing the sun (S) or in the shade (H) were harvested and stored for 13 days at 20 °C. An evaluation of fruit soluble solids, acidity, color, starch degradation, firmness, cell wall yield, pectin and matrix glycan solubilization, depolymerization, and monosaccharide composition was carried out. Sun-exposed pears showed more advanced color development and similar levels of starch degradation, sugars, and acids than shaded fruit. Sunlight-grown pears were at harvest firmer than shade-grown pears. Both fruit groups softened during storage at 20 °C, but even after ripening, sun-exposed pears remained firmer. Sunlight exposure did not have a great impact on pectin molecular weight. Instead, at harvest a higher proportion of water-solubilized uronic acids and alkali-solubilized neutral sugars and a larger mean molecular size of tightly bound glycans was found in sun-exposed pears. During ripening cell wall catabolism took place in both sun- and shade-grown pears, but pectin solubilization was clearly delayed in sun-exposed fruit. This was associated with decreased removal of RG I-arabinan side chains rather than with reduced depolymerization.


Assuntos
Parede Celular/química , Polissacarídeos/química , Polissacarídeos/metabolismo , Pyrus/metabolismo , Pyrus/efeitos da radiação , Parede Celular/metabolismo , Pyrus/química , Pyrus/crescimento & desenvolvimento , Luz Solar
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