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1.
J Chromatogr A ; 1645: 462107, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-33857677

RESUMO

In the analysis of contaminants in food products, sample preparation is performed by proper adsorbents, whose choice is crucial to eliminate matrix interference. In this work we modified SBA-15 adsorbents by functionalization with (3-aminopropyl)-triethoxysilane (SBA-15-APTES) and N-[3-(trimethoxysilyl)propyl]aniline (SBA-15-AN) aiming to use them for the first time in the clean-up step of a QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction of micropollutants from strawberry, a sugar rich fruit. After physico-chemical characterization by nitrogen adsorption, infrared spectroscopy and thermogravimetric analysis, the adsorption capabilities of SBA-15 sorbents and possible interaction mechanisms were studied at different pH (2.1-8.5) for glucose, sucrose and fructose at concentrations characteristic of those found in strawberries. The performance of the two SBA-15 sorbents was compared with that of commercial PSA (primary secondary amine), usually proposed in QuEChERS protocols. Both SBA-15 materials exhibit up to 30% higher adsorption than PSA, suggesting their possible QuEChERS application. Synthesized SBA-15 adsorbents were hence used as innovative dispersive sorbents in the QuEChERS extractions of 13 PAHs and 14 PCBs from strawberry. For PCBs, SBA-15-AN provides better matrix removal than PSA and comparable extraction recoveries around 90%. For PAHs, the use of SBA-15-AN has the advantage of lower relative standard deviation (7%) than PSA (19%).


Assuntos
Poluentes Ambientais/análise , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Adsorção , Fragaria/química , Frutas/química , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
2.
Food Chem ; 354: 129502, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33752118

RESUMO

The dissipation behaviors and exposure risks of individual and joint application of procymidone and carbendazim in greenhouse strawberries were studied. The initial concentrations were similar after individual or joint applications, while the dissipation half-lives and finial concentrations were significantly different. After joint application, the dissipation half-lives of procymidone and carbendazim were 12.9 and 16.0 days, respectively, which were about 1.8 times higher than those after individual application. Furthermore, the final residues under joint application condition were 1.8-3.5 times higher than those under individual application condition. The joint application decreased the dissipation rates of procymidone or carbendazim in strawberries, and increased the final residue concentrations. The dietary intake risks of procymidone and carbendazim (whether applied individually or jointly) were no higher than 0.12, which were acceptable for human health. This work would shed a light for the guidance of the joint application and risk assessment of the typical fungicides in strawberry.


Assuntos
Benzimidazóis/metabolismo , Compostos Bicíclicos com Pontes/metabolismo , Carbamatos/metabolismo , Fragaria/química , Benzimidazóis/análise , Compostos Bicíclicos com Pontes/análise , Carbamatos/análise , Cromatografia Líquida de Alta Pressão , Fragaria/metabolismo , Efeito Estufa , Meia-Vida , Humanos , Resíduos de Praguicidas/análise , Medição de Risco , Espectrometria de Massas por Ionização por Electrospray
3.
Food Chem ; 350: 129199, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33610843

RESUMO

The present study aimed to develop a new bio-nanocomposite film based on gum arabic (GA) reinforced with cellulose nanocrystals (CNC). CNC was successfully fabricated and its microstructure was characterized. Subsequently, the effects of CNC on the rheological, physicochemical and functional properties of GA-based films were systematically evaluated. Results showed that the tensile strength (2.21 MPa) and elongation at break (62.79%) of film incorporated with 4% (w/w) CNC were effectively increased compared with the GA film (1.08 MPa and 42.50%). Additionally, 4% CNC reduced the water vapor and oxygen permeability by 10.61% and 25.30% respectively, while improved the ultraviolet light barrier and thermal stability of film. The well dispersion and filling effect of nanofiller contributed to form a compact and homogeneous film structure. Furthermore, the film containing 4% CNC decreased the weight loss of strawberries by 23.80% compared with the control group, thus delaying the deterioration of strawberry quality during storage.


Assuntos
Celulose/química , Conservação de Alimentos/métodos , Fragaria/química , Goma Arábica/química , Nanocompostos/química , Nanopartículas/química , Permeabilidade , Reologia , Vapor/análise , Resistência à Tração
4.
Food Chem ; 351: 129284, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33640773

RESUMO

Coating damage destroys the integrity features critical for maintaining the modified atmosphere inside the fruit. In this study, we developed a self-healing edible coating that maintains its barrier properties for extending the shelf life of strawberries. The coating was fabricated via the layer-by-layer assembly of chitosan (CS) and sodium alginate (SA). (SA/CS)3 formed by three assembly cycles could completely heal the visibly damaged area by treating water. The mechanical properties and the water and oxygen rates of the healed coating were 97%, 63%, and 95%, respectively, of the intact coating. (SA/CS)3 coating effectively delayed strawberry deterioration. Moreover, the coating reduced the impact of coating damage on strawberries by restoring the coating barrier properties. The present findings have important implications for solving the reduction in freshness caused by coating damage.


Assuntos
Filmes Comestíveis , Conservação de Alimentos/métodos , Alginatos/química , Quitosana/química , Qualidade dos Alimentos , Fragaria/química , Fragaria/metabolismo , Frutas/química , Frutas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Oxigênio/química , Polietilenotereftalatos/química , Resistência à Tração , Água/química
5.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466340

RESUMO

Male hypogonadism is often treated by testosterone (T) replacement therapy such as oral administration of the ester prodrug, testosterone undecanoate (TU). However, the systemic exposure to T following oral TU is very low due to esterase-mediated metabolism, particularly in the small intestine. The aim of this work was to examine the esterase-inhibitory effect of natural fruit extract of strawberry (STW) on the intestinal degradation of TU as a potential approach to increasing the oral bioavailability of T. Herein, the hydrolysis of TU was assessed in fasted state simulated intestinal fluid with added esterase activity (FaSSIF/ES) and Caco-2 cell homogenates in the presence of STW extract. It is noteworthy that STW substantially inhibited the degradation of TU in FaSSIF/ES and Caco-2 cell homogenates at concentrations that could be achieved following oral consumption of less than one serving of STW fruit. This can significantly increase the fraction of unhydrolyzed TU in the intestinal lumen as well as in enterocytes. In addition, it was demonstrated that TU has high intestinal lymphatic transport potential as the association of TU with plasma-derived human chylomicrons was in the range of 84%. Therefore, oral co-administration of TU with STW could potentially increase the intestinal stability of TU and consequently the contribution of lymphatically delivered TU to the systemic exposure of T in vivo.


Assuntos
Fragaria/química , Intestino Delgado/metabolismo , Sistema Linfático/metabolismo , Extratos Vegetais/administração & dosagem , Testosterona/análogos & derivados , Testosterona/metabolismo , Administração Oral , Adulto , Disponibilidade Biológica , Células CACO-2 , Humanos , Hidrólise , Intestino Delgado/efeitos dos fármacos , Sistema Linfático/efeitos dos fármacos , Masculino
6.
Food Chem ; 340: 127925, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889213

RESUMO

The addition of strawberry pulp to ketchup sauces may be an alternative to attend the consumers' demand for innovative products with functional appeal. Sauces were made using different tomato/strawberry pulp ratios (100:0; 75:25; 50:50; 25:75; 0:100) and characterized for the physicochemical characteristics, bioactive compounds, antioxidant activity, and consumers' acceptance. The strawberry-enriched ketchup sauces presented higher phenolics, total flavonoids, antioxidant activity, and increased fluidity, and lower browning index, hue angle, chroma, pH, and Bostwick consistency. The antioxidant activities (ABTS and DPPH) were positively correlated with phenolics (r = 0.96 and 0.91) and flavonoids (r = 0.92 and 0.89) contents, respectively. The replacement of up to 50% tomato pulp by strawberry pulp did not change the acidity, flavor, and overall acceptance of the samples. The strawberry pulp has proven to be an effective alternative to increase the concentrations of bioactive compounds while reducing the amount of sugar used in traditional ketchup formulations.


Assuntos
Antioxidantes/química , Alimentos , Fragaria/química , Lycopersicon esculentum/química , Adolescente , Adulto , Feminino , Flavonoides/análise , Humanos , Masculino , Pessoa de Meia-Idade , Fenóis/análise , Paladar , Adulto Jovem
7.
J Sci Food Agric ; 101(2): 441-448, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32648586

RESUMO

BACKGROUND: Low molecular-weight phenolic fractions (LMPFs) were extracted from Albion (LMPF-A) and Camarosa (LMPF-C) strawberry cultivars. Their antibacterial activity against Listeria monocytogenes and Salmonella Typhimurium cocktails in vitro and in vivo was investigated using strawberry juice as a food model. This study also sought to determine their antibacterial mechanism. RESULTS: Quercetin was identified as a principal compound in both phenolic fractions. The minimum bactericide concentration (MBC) values were 750 and 850 µg mL-1 (LMPF-C) and 800 and 950 µg mL-1 (LMPF-A) against S.Typhimurium and L. monocytogenes, respectively. The possible antibacterial activity of the phenolic extracts could be related to the release of phosphate and potassium ions, the effect of the disruption of membrane integrity on L. monocytogenes, and the effect of the inhibition of dihydronicotinamide adenine dinucleotide (NADH) oxidase activity on S. Typhimurium. Quercetin and kaempferol were the most active compounds in producing bacterial damage. Strawberry juice supplemented with the phenolic fractions and incubated at 37, 20, and 4 °C reduced bacterial viability; moreover, after treatment with the phenolic fraction at the lowest temperature, no viable cells were detected after 7 days' incubation. Salmonella was more sensitive to the supplements than Listeria in strawberry juice. CONCLUSIONS: This study could form the basis for the development of natural antibacterial agents that could be included in natural juice or used by the pharmaceutical industry. © 2020 Society of Chemical Industry.


Assuntos
Antibacterianos/farmacologia , Fragaria/química , Sucos de Frutas e Vegetais/microbiologia , Listeria monocytogenes/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Antibacterianos/química , Frutas/química , Sucos de Frutas e Vegetais/análise , Listeria monocytogenes/crescimento & desenvolvimento , Extratos Vegetais/química , Polifenóis/química , Salmonella typhimurium/crescimento & desenvolvimento
8.
Carbohydr Polym ; 251: 117117, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142652

RESUMO

The development of biopolymer films is crucial for the replacement of conventional plastics. Tremendous effort is made to improve their performances by introducing biopolymers through the film manufacturing process. Herein, a sandwich-architectured film was proposed to efficiently improve the adhesion between the PS and PLA layers by using octenyl succinic anhydride-modified pea starch (OMPS) layer as the interlayer, leading to a highly mechanically enhanced interpenetrating network. Accordingly, the properties of the films were enhanced due to the synergism effect of sandwich architecture. In particular, the WVP value of the sandwich-architectured films (0.25 ∼ 0.89×10-10g·m-1·s-1·Pa-1) decreased more than 7-fold compared with the OMPS20 film, and the OP value of the sandwich-architectured films (0.256 ∼ 1.229×10-12cm3·m·m-2·s-1·Pa-1) decreased more than 10-fold in comparison to the PLA film. Benefitting from the characteristics investigated above, the films exhibited a favorable effect on strawberry storage. Overall, the fabricated eco-friendly sandwich-architectured films have shown great potential for biodegradable packaging applications.


Assuntos
Conservação de Alimentos/métodos , Fragaria/química , Ervilhas/química , Poliésteres/química , Amido/química , Embalagem de Alimentos/métodos , Frutas/química , Amido/análogos & derivados , Resistência à Tração
9.
Molecules ; 25(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321861

RESUMO

The natural antioxidant hydroxytyrosol (HT) was used to functionalize a strawberry puree. The effect of the antioxidant on the stability of the two bioactive forms of vitamin C (ascorbic acid-AA and dehydroascorbic acid-DHAA) in strawberry puree stored at 4 °C, compared with the effect on a model system of AA in water, was investigated. In the absence of HT, the concentration of vitamin C in strawberry puree decreased but not in the model system. Low concentrations of HT in strawberry puree (0.05 and 0.1 mg HT/g puree) stabilized vitamin C and improved its antioxidant activity. However, at high concentrations of HT (from 0.5 mg HT/g puree), although the antioxidant activity improved, degradation of vitamin C occurred. Therefore, the concentration of HT used to obtain a functionalized strawberry puree it is very important. An adequate concentration increases the antioxidant activity and protects vitamin C from degradation, developing a functional food. However, an inadequate concentration of HT affects the vitamin C content, which is essential for the human diet because it cannot be biosynthetized by the organism.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Fragaria/química , Álcool Feniletílico/análogos & derivados , Ácido Ascórbico/química , Ácido Ascórbico/farmacologia , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Estrutura Molecular , Oxirredução/efeitos dos fármacos , Álcool Feniletílico/química , Soluções , Temperatura
10.
J Environ Sci Health B ; 55(10): 865-875, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32657214

RESUMO

This research aimed at implementing and validating a method for analysis of pesticide residues in crops. QuEChERS extraction method with PSA purification was used following analyzes by gas chromatography with tandem mass spectrometry in Selected Reaction Monitoring mode. A short run method was successfully developed for the determination of 41 pesticides, confirmed by two precursor-products for each analyte. The calibration curve for each analyte was linear at concentration range from 1 to 500 µg kg-1 with correlation coefficients higher than 0.99, low limits of detection (0.03 - 10.22 µg kg-1) and satisfactory precision. The developed method was used to investigate apples; mangos; strawberries; cucumbers and tomatoes from the Rio de Janeiro Food Distribution Center (CEASA).Most of the targeted pesticides (78%) were below detection limits. Apple and strawberry presented the highest pesticide contamination levels, many of which are not authorized by tthe Brazilian national regulatory agency (ANVISA).


Assuntos
Produtos Agrícolas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Piretrinas/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Triazinas/análise , Brasil , Cucumis sativus/química , Contaminação de Alimentos/análise , Fragaria/química , Lycopersicon esculentum/química , Malus/química , Mangifera/química
11.
Food Chem ; 331: 127203, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32574943

RESUMO

Effects of high hydrostatic pressure (HHP) (50, 100, 150, 200 and 250 MPa) pretreatment on water mobility and distribution, drying duration, microstructure, color, cell wall fraction and tissue structure of strawberry slices were investigated. HHP significantly increased water mobility of the strawberry slices, resulting in the reduction of drying duration by 9-24%. As the pretreatment pressure was increased, redness value and anthocyanin content continuously increased, soluble pectin (SBP) content increased and then decreased, while the contents of protopectin (PTP) and cellulose decreased. After the HHP pretreatment, chromoplasts and moisture was distributed more uniformly in the strawberry slices. Microscopy images showed the formation of microscopic holes or channels in the matrix and the breakdown of tissue structure by HHP. Results suggested HHP pretreatment disrupted the integrity of the fresh strawberry which enhanced the drying efficiency and migration of the chromoplasts during the vacuum-freeze drying process.


Assuntos
Fragaria/química , Liofilização , Antocianinas/química , Antocianinas/metabolismo , Celulose/química , Cor , Fragaria/metabolismo , Pressão Hidrostática , Espectroscopia de Ressonância Magnética , Pectinas/química , Pectinas/metabolismo , Água/química
12.
Food Chem ; 329: 127213, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516713

RESUMO

Chitosan and whey protein isolate (WPI) conjugate films were prepared as a novel matrix for encapsulating and extending the postharvest shelf life of strawberries. Film forming solutions of chitosan, WPI, and chitosan-WPI conjugate were mixed with glycerol, casted for films at 60 ± 2 °C and assessed for their colour, water vapour and oxygen transfer rate, textural, functional groups and secondary structure, thermal, crystallinity, and antioxidant properties. Chitosan-WPI conjugate films were applied as an edible coating on strawberries, and studied for storage stability at 5 °C and 20 °C by assessing physical and biochemical parameters. A considerable reduction in colour indices, weight loss, pH and titratable acidity, reducing sugars, ascorbic acid, total phenolics, DPPH and ABTS assay was noted in the coated strawberries over the control at both the studied temperatures. The control strawberries had a shelf life of 5 and 3 days, whereas coating enhanced the shelf life of strawberries to 8 and 5 days when stored at 5 °C and 20 °C, respectively.


Assuntos
Quitosana/química , Conservação de Alimentos/métodos , Proteínas do Soro do Leite/química , Antioxidantes/química , Ácido Ascórbico/análise , Varredura Diferencial de Calorimetria , Cor , Fragaria/química , Fragaria/metabolismo , Frutas/química , Frutas/metabolismo , Glicerol/química , Concentração de Íons de Hidrogênio , Fenóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
13.
J Environ Sci Health B ; 55(8): 712-718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32515641

RESUMO

The degradation under field conditions and the residue behavior of etoxazole during juicing and purée making was evaluated. Etoxazole residues were determined by HPLC-UV at six different Pre Harvest Intervals (PHIs) as to estimate the degradation of residue in fruits. Samples with significant residues were processed and residue were determined after juicing and purée making. The effect of washing was also estimated. Processing Factors (PFs) for etoxazole after each step were less than 1 and the PFs of the overall processes were lower than 0.85 for washing fruits, 0.13 for juice and 0.04 for purée. The studied processes could obviously reduce the pesticide residues that are present in the raw strawberries. Uncertainties in the use of the PFs were identified due to the potential formation of metabolites during the processes.


Assuntos
Contaminação de Alimentos/análise , Indústria de Processamento de Alimentos/métodos , Fragaria/química , Oxazóis/análise , Cromatografia Líquida de Alta Pressão , Egito , Frutas/química , Resíduos de Praguicidas/análise
14.
Food Chem ; 328: 127106, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32485584

RESUMO

In this work, based on the strawberry-like SiO2/Ag nanocomposites (SANC) immersed filter paper, a newly surface-enhanced Raman scattering (SERS) substrate was constructed for the detection of acrylamide (AAm) in food products. To construct filter paper-based SANC (F-SANC) SERS substrates, SiO2 nanoparticles (SNP) were firstly synthesized and acted as carriers. After that, the in-situ preparation of silver nanoparticles (Ag NP) on SNP surface was carried out to form the strawberry-like three-dimensional (3D) structure of SANC. Finally, SANC were entangled into the filter paper to produce nanoarchitecture, thus providing enhanced plasmon resonance between SANC with strong SERS signal. Under the optimized conditions, the method exhibited good performance toward AAm with a vast linear response from 0.1 nM to 50 µM (R = 0.9935), limit of detection (LOD) of 0.02 nM (S/N = 3), and the recoveries of 80.5%~105.6% for practical samples. This strategy showed good robustness in the rapid and sensitive detection of AAm, which could be a promising strategy in food analysis and verification.


Assuntos
Acrilamida/análise , Análise de Alimentos/métodos , Nanopartículas Metálicas/química , Nanocompostos/química , Análise Espectral Raman/métodos , Filtração/instrumentação , Análise de Alimentos/instrumentação , Fragaria/química , Limite de Detecção , Dióxido de Silício/química , Prata/química
15.
Sci Rep ; 10(1): 8196, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424195

RESUMO

An increasing interest in the development of products of natural origin for crop disease and pest control has emerged in the last decade. Here we introduce a new family of strawberry acyl glycosides (SAGs) formed by a trisaccharide (GalNAc-GalNAc-Glc) and a monounsaturated fatty acid of 6 to 12 carbon atoms linked to the glucose unit. Application of SAGs to Arabidopsis thaliana (hereafter Arabidopsis) plants triggered a transient oxidative burst, callose deposition and defense gene expression, accompanied by increased protection against two phytopathogens, Pseudomonas viridiflava and Botrytis cinerea. SAGs-induced disease protection was also demonstrated in soybean infected with the causal agent of target spot, Corynespora cassiicola. SAGs were shown to exhibit important antimicrobial activity against a wide-range of bacterial and fungal phytopathogens, most probably through membrane destabilization, and the potential use of SAGs as a biofungicide for postharvest disease protection was demonstrated on lemon fruits infected with Penicillium digitatum. Plant growth promotion by application of SAGs was shown by augmented primary root elongation, secondary roots development and increased siliques formation in Arabidopsis, whereas a significant increment in number of seed pods was demonstrated in soybean. Stimulation of radicle development and the induction of an auxin-responsive reporter system (DR5::GUS) in transgenic Arabidopsis plants, suggested that SAGs-stimulated growth at least partly acts through the auxin response pathway. These results indicate that strawberry fatty acid glycosides are promising candidates for the development of environmental-friendly products for disease management in soybean and lemon.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Fragaria/química , Glicosídeos/química , Glicosídeos/farmacologia , Doenças das Plantas/prevenção & controle , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/microbiologia , Bioensaio , Botrytis/efeitos dos fármacos , Botrytis/fisiologia , Doenças das Plantas/microbiologia , Pseudomonas/efeitos dos fármacos , Pseudomonas/fisiologia
16.
Food Chem ; 321: 126747, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276147

RESUMO

The strawberry fruit is perishable due to its high water content and soft texture, yet exhibits pleasant organoleptic and nutritional profile. Here we conducted a metabolomics-driven analysis followed by linear modelling to dissect the molecular processes in strawberry postharvest. Fruits from five cultivars were harvested and refrigerated during a ten-day period under three different atmospheres: ambient, CO2-enriched and O3-enriched. These analyses revealed that metabolites involved in, (i) organoleptic and nutritional properties; (ii) stress tolerance displayed duration and postharvest treatment-dependent levels. Ozone-enriched atmosphere appears to counteract postharvest negative effects, with fruits exhibiting lower levels of fermentative metabolites when compared to fruits kept in an ambient atmosphere. Furthermore, metabolic reconfiguration towards the synthesis of protective metabolites of those fruits can possibly confer enhanced tolerance to postharvest abiotic stresses. Finally, results from the linear modelling identified metabolites which could be used as biomarkers to assess strawberry quality during its postharvest shelf life.


Assuntos
Armazenamento de Alimentos/métodos , Fragaria/metabolismo , Frutas/metabolismo , Biomarcadores/metabolismo , Dióxido de Carbono/farmacologia , Fragaria/química , Fragaria/efeitos dos fármacos , Frutas/química , Frutas/efeitos dos fármacos , Modelos Lineares , Ozônio/farmacologia , Estresse Fisiológico
17.
J Chromatogr A ; 1621: 461038, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32199674

RESUMO

A QuEChERS method was optimized and validated for the LC-MS/MS analysis of perfluoro-n-pentanoic acid (PFPeA), perfluoro-1-butanesulfonic acid (PFBuS), perfluoro-n-hexanoic acid (PFHxA), perfluoro-n-heptanoic acid (PFHpA), perfluoro-1-hexanesulfonic acid (PFHxS), perfluoro-n-octanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA), perfluoro-1-octanesulfonic acid (PFOS) and perfluoro-n-decanoic acid (PFDA) in freeze-dried strawberry and olive, as model fruits characterized by very different chemical compositions. The method was evaluated for apparent recovery, intra-day and inter-day precision, matrix effect and recovery. The method optimized for strawberry provided for most compounds absolute values of matrix effect (|ME%|) ≤ 11%, except for PFHxA, which showed a signal suppression of 22%. The extraction efficiency was tested at the spike levels 500-5000 pg/g d.w. for PFPeA, PFBuS, and PFHxA, and 100-1000 pg/g d.w. for the other target analytes, evidencing as a whole recoveries in the range of 65-89%. For olive fruits, due to their high fat content, an ultrasound-assisted extraction was necessary to obtain an efficient sample disgregation so as to increase the extraction yield and its precision. Moreover, a d-SPE clean-up with GCB allowed to achieve |ME%| ≤ 8% (except for PFBuS, which showed a signal enhancement of 19%) and recoveries calculated at the aforementioned spike levels were in the range 75-97%. The two methods provided very good linearity (R2 ≥ 0.9984) from 10,000 pg/g down to compound specific quantification limits, which were included in the ranges of 2.9-393 pg/g and 2.6-127 pg/g for strawberry and olive fruit, respectively. The methods were applied to the analysis of PFAAs in strawberry and olive fruits commercially available in two Italian supermarkets, as well as obtained under irrigation with various treated wastewaters (TWWs), evidencing in both cases a higher PFAAs occurrence in olives than in strawberry. However, PFAAs concentrations determined in the investigated fruit matrixes were quite low, being their sum 1.9 ng/g d.w. in the worst case (i.e. olive fruits grown under irrigation with TWWs).


Assuntos
Cromatografia Líquida/métodos , Fluorcarbonetos/análise , Fragaria/química , Frutas/química , Olea/química , Espectrometria de Massas em Tandem/métodos , Irrigação Agrícola , Produtos Agrícolas/química , Águas Residuárias
18.
J Food Sci ; 85(3): 771-780, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32043600

RESUMO

Consumers consistently note that there is room for improvement in the flavor of commercial strawberries. Fruit flavor and aroma are affected by both genetics and environment. This work tests the hypothesis that sensory quality may be manipulated using postharvest light treatments. Individual detached fruits representing two different cultivars received a 24-hr treatment of 100 µmol m-2 s-1 blue LED light while the control was kept in complete darkness. Following treatment, samples were analyzed for flavor volatiles, sugars, acids, firmness, and sensory differences in human trials. Fruits were rated for overall liking, texture, sweetness, sourness, and overall strawberry flavor intensity (OSFI) on the sensory and hedonic versions of the global intensity scale (GIS). A positive treatment effect was observed for "Strawberry Festival" fruit for the overall liking rating. A triangle test revealed a significant treatment effect, as light-treated fruit tested higher in many flavor volatiles including those known to contribute to sweetness in strawberries. Levels of several volatiles were consistently higher in the treated fruit across all four harvests: acetic acid hexyl ester, butanoic acid octyl ester, methyl isovalerate, and pentanoic acid ethyl ester. The results show that postharvest light treatment can be used to modulate sensory quality of fruit, perhaps offering a means to complement genetic efforts in fruit flavor and aroma improvement. PRACTICAL APPLICATION: The results indicate that it may be possible to increase the sensory quality of strawberry fruits using an inexpensive and noninvasive light treatment. Light may be applied during transport or storage to improve fruit quality. This concept could also be extended into other realms of storage, such as residential and commercial refrigeration, further increasing the quality impact of the approach.


Assuntos
Aromatizantes/química , Fragaria/química , Frutas/efeitos da radiação , Fragaria/efeitos da radiação , Frutas/química , Humanos , Luz , Odorantes/análise , Paladar , Compostos Orgânicos Voláteis/química
19.
Food Chem ; 316: 126297, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32044703

RESUMO

Strawberry (cv. Senga Sengana) and raspberry (cv. Veten) were processed into jams at 60, 85 or 93 °C and stored at 4 or 23 °C for 8 and 16 weeks. High processing temperature reduced ascorbic acid, total monomeric anthocyanins (TMA) and total phenolics (TP) in strawberries (p<0.05), but not in raspberries. Processing temperature had minor effect on bioactive compounds in the jams during storage (<10% explained variance), but influenced color (L*, °Hue, Chroma), especially L* of the strawberry jams (73.3%). Storage period explained most of the variance in ascorbic acid (>90%), TMA (>42%) and TP (>69%). Storage temperature affected stability of anthocyanins, but had minor effect on ascorbic acid, which declined rapidly independent of storage temperature. Storage temperature also explained most of the variance (>40%) in Chroma of the jams and L* of raspberry jams (53%). Bioactive compounds and color were more stable in raspberry jams than in strawberry jams.


Assuntos
Antocianinas/química , Ácido Ascórbico/química , Alimentos em Conserva/análise , Fragaria/química , Rubus/química , Cor , Frutas , Fenóis , Temperatura
20.
Carbohydr Res ; 489: 107932, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32035290

RESUMO

Two Pseudomonas strains were isolated from the strawberry leaves. The O-antigens were obtained using phenol-water method and mild acid degradation. The following structures of the O-polysaccharides were established by sugar analysis and 2D NMR spectroscopy: OPS of Pseudomonas koreensis BIM B-970G →3)-α-D-FucNAcp-(1 â†’ 2)-ß-D-Quip3NAc-(1 â†’ 3)-α-L-6dTalp4OAc-(1→ OPS of Pseudomonas oryzihabitans BIM B-1072G →4)-α-L-FucpNAm3OAc-(1 â†’ 3)-α-D-QuipNAc-(1 â†’ 4)-ß-D-GlcpNAc3NAcA-(1→ Where Am - acetimidoyl.


Assuntos
Fragaria/química , Folhas de Planta/química , Polissacarídeos/isolamento & purificação , Pseudomonas/química , Configuração de Carboidratos , Espectroscopia de Ressonância Magnética , Polissacarídeos/química
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