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1.
Food Sci Technol Int ; 21(2): 94-103, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24216324

RESUMO

The combination of temperature and atmosphere composition for storage of Pyrus communis L. 'Rocha' treated with 1-methylcyclopropene was investigated. Fruits treated with 312 nl l(-1) 1-methylcyclopropene were stored at 0 ℃ and 2.5 ℃ in air and controlled atmosphere (CA) (3.04 kPa O2+ 0.91 kPa CO2). Fruits were removed from storage after 14, 26 and 35 weeks, transferred to shelf-life at approximately 22 ℃ and assessed for ripening and quality, symptoms of superficial scald and internal browning and the accumulation of biochemical compounds related to scald after 0, 1 and 2 weeks. Superficial scald occurred only in fruits stored for 35 weeks in air at 2.5 ℃. Levels of conjugated trienols and α-farnesene increased during the first 26 weeks in storage, remaining constant thereafter. During shelf-life, conjugated trienols were higher in fruits stored in air at 2.5 ℃. Internal browning developed in shelf-life after 26 weeks at 2.5 ℃. Pears in air at 2.5 ℃ were not able to stand a 2-week shelf-life after 35 weeks of storage, while fruits stored at 0 ℃ under CA ripened slowly after the same storage period. The retention of firmness during shelf-life of 1-methylcyclopropene-treated 'Rocha' pear can be overcome by elevating the storage temperature from 0 ℃ to 2.5 ℃, but CA is a required complement to avoid excessive softening after long-term storage. The ratio carotenoid/chlorophyll increased during storage and shelf-life, as plastids senesced. CA reduced the rate of chlorophyll loss during the first 14 weeks in storage, but its effect was reduced afterwards. 'Rocha' pear treated with 1-methylcyclopropene had a similar post-harvest behaviour during long-term storage at 0 ℃ in air or at 2.5 ℃ under CA.


Assuntos
Ar , Ciclopropanos , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Frutas , Pyrus , Temperatura , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Humanos
2.
Molecules ; 19(10): 15799-823, 2014 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-25271425

RESUMO

Arbutus unedo L. (strawberry tree) has a circum-Mediterranean distribution, being found in western, central and southern Europe, north-eastern Africa (excluding Egypt and Libya) and the Canary Islands and western Asia. Fruits of the strawberry tree are generally used for preparing alcoholic drinks (wines, liqueurs and brandies), jams, jellies and marmalades, and less frequently eaten as fresh fruit, despite their pleasing appearance. An overview of the chemical composition of different parts of the plant, strawberry tree honey and strawberry tree brandy will be presented. The biological properties of the different parts of A. unedo and strawberry tree honey will be also overviewed.


Assuntos
Ericaceae/química , Frutas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Bebidas , Mel
3.
Food Chem Toxicol ; 56: 136-44, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23422034

RESUMO

"Água-mel" is a honey-based product produced in Portugal for ancient times. Several attributes have been reported to "água-mel" particularly in the alleviation of simple symptoms of upper respiratory tract. Samples of "água-mel" from diverse beekeepers from different regions of Portugal were studied in what concerns antimicrobial, antioxidant and antiviral properties. The amounts of phenol and brown pigment were also evaluated and correlated with the antioxidant activities. A great variability on the levels of these compounds was found among samples which were responsible for the variability detected also on the antioxidant activities, independent on the method used. Generally, antioxidant activity correlated better with brown pigments' amount than with phenols' content. The antimicrobial activity found for "água-mel" samples confirm the virtues reported by popular findings. In addition, this work also reveals the antiviral properties of "água-mel" evidenced by a decrease on the infectivity of the Qß bacteriophage.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Antivirais/farmacologia , Mel/análise , Benzotiazóis/análise , Inibidores de Lipoxigenase/análise , Reação de Maillard , Óxido Nítrico/análise , Polímeros/análise , Polifenóis/análise , Portugal , Ácidos Sulfônicos/análise
4.
Nat Prod Res ; 27(8): 743-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22724515

RESUMO

The variability of the volatile profile of 70 propolis samples from acaricide-treated and -untreated beehives maintained at Algarve (Portugal) was evaluated. Propolis samples were collected in three regions of Algarve at three different periods. Cluster analysis based on the propolis volatiles' chemical composition defined two main clusters, not related to the time of year, collection site, altitude, temperature or humidity ranges, and was based mainly on the relative amounts of viridiflorol, n-tricosane and n-nonadecane for cluster I. Cluster II was mainly characterised by the high thymol content, followed by viridiflorol, n-tricosane and n-nonadecane. The presence of higher thymol levels in propolis samples from cluster II may reflect the long use of an acaricide with thymol as main active ingredient. All samples showed an intense rock-rose aroma supported by the presence of characteristic Cistus and labdanum oil volatile components. Given the nowadays frequent propolis household use, volatiles thorough characterisation may assist in its quality assessment.


Assuntos
Acaricidas , Óleos Voláteis/química , Própole/química , Timol , Animais , Criação de Abelhas , Abelhas , Análise por Conglomerados , Portugal
5.
Recent Pat Food Nutr Agric ; 4(2): 114-22, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22640404

RESUMO

Fresh fruit and vegetables consumption has increased in the past few years due to the enhanced awareness of consumers for healthy food. However, these products are highly perishable, and losses can be of great significance if postharvest correct management is not provided. Fresh-cut products are of increasing importance, since they are presented to the consumer in a state that allows for direct and immediate consumption. However, those products are even more perishable since cutting can induce a series of senescence associated responses to wounding, and are more susceptible to microbial spoilage. Edible coatings, which intend to reduce ripening processes and protect the fruit from water loss and spoilage may be a good way to enhance the shelf life of these products. More recently, the inclusion of additives into these edible coatings to increase their effectiveness, such as essential oils and their constituents with antimicrobial and antioxidant activities, has been reported and patented.


Assuntos
Anti-Infecciosos , Antioxidantes , Microbiologia de Alimentos , Conservantes de Alimentos , Frutas , Óleos Voláteis , Patentes como Assunto , Senescência Celular , Dieta , Conservação de Alimentos , Humanos , Água
6.
J Agric Food Chem ; 58(10): 6173-81, 2010 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-20411941

RESUMO

Consumption of minimally processed fruit and vegetables has increased significantly in the past few years due to the consumers' life style. The aim of this study was to evaluate the effect of treatment with ascorbic acid or calcium chloride on the quality parameters of fresh-cut kiwifruit prepared from fruit previously stored for 3 months, either treated or not treated with 1-methylcyclopropene (1-MCP) before storage. Harvested fruit were treated with 1 microL L(-1) 1-MCP for 20 h at room temperature ( approximately 20 degrees C) (MCP) or had no treatment (C) and were then stored at 0 degrees C. After 3 months, fruit were removed from storage, peeled, and cut longitudinally in quarters, dipped in 2% ascorbic acid (Asc), 2% calcium chloride (Ca), or just water (cont), and kept at 2 degrees C for 8 days. Measurements of firmness, soluble solids content (SSC) ( degrees Brix), color (CIE L*, a*, b*), electrolyte leakage, sugars, organic acids, total phenolics, and antioxidant activity (DPPH and ABTS) were performed at 0, 4, and 8 days. A taste panel was performed on the seventh shelf life day. It was shown that whole MCP-treated kiwifruit kept better than the control through the 3 months storage, this effect being lost through the fresh-cut shelf life period. Furthermore, the postcut dip on 2% CaCl(2) was effective on delaying softening and browning of fresh-cut kiwifruit, which were also the fruit preferred by panelists. Both ascorbic acid and CaCl(2) were effective on preserving or improving nutritional properties (phenolics, ascorbic acid, DPPH, and ABTS) mainly in the first 4 days of shelf life. The CaCl(2) had a further beneficial effect until 8 shelf life days. It is suggested that CaCl(2) is better in keeping overall quality through 8 days of shelf life at 2 degrees C in fresh-cut kiwifruit followed by Asc, and 1-MCP has negligible effect in the conditions of this experiment.


Assuntos
Actinidia , Ciclopropanos/administração & dosagem , Etilenos/antagonistas & inibidores , Manipulação de Alimentos/métodos , Frutas/química , Valor Nutritivo , Antioxidantes/análise , Ácido Ascórbico/administração & dosagem , Cloreto de Cálcio/administração & dosagem , Carboidratos/análise , Ácidos Carboxílicos/análise , Conservação de Alimentos , Frutas/crescimento & desenvolvimento , Humanos , Fenóis/análise , Controle de Qualidade , Sensação
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