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1.
Food Chem ; 303: 125396, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446365

RESUMO

This study describes the determination of lead at trace levels by slotted quartz tube flame atomic absorption spectrophotometry (SQT-FAAS) after preconcentration by the help of stearic acid coated magnetic nanoparticle (SAC-MNPs) based sonication assisted dispersive solid phase extraction (SA-DSPE). SAC-MNPs were used due to their easy separation advantages by the application of external magnetic field. All extraction parameters were optimized by response surface methodology based experimental design. The experimented data was evaluated by the analysis of variance. Under the optimum conditions, about 31 folds enhancement in detection power was obtained over the conventional FAAS. The recovery results obtained for samples spiked at 60 and 120 ng mL-1 were 106.6 and 102.6%, respectively, validating the method as accurate and applicable to the red pepper matrix. The percent relative standard deviations of the results were under 5.0% even at low concentrations that established high precision for replicate extractions and instrumental readings.


Assuntos
Capsicum/química , Chumbo/análise , Chumbo/isolamento & purificação , Microextração em Fase Líquida/métodos , Magnetismo/métodos , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Contaminação de Alimentos/análise , Frutas/química , Magnetismo/instrumentação , Nanopartículas de Magnetita/química , Quartzo/química , Sensibilidade e Especificidade , Sonicação , Ácidos Esteáricos/química
2.
Food Chem ; 306: 125629, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629298

RESUMO

To understand the mechanism of the color formation of pepper fruit, integrative analysis of the metabolome and transcriptome profiles was performed in pepper varieties with 4 different fruit colors. A total of 188 flavonoids were identified, and most of the anthocyanins, flavonols and flavones showed markedly higher abundances in purple variety than in other varieties, which was linked to the high expression of flavonoid synthesis and regulatory genes. Using weighted gene co-expression network analyses, modules related to flavonoid synthesis and candidate genes that regulate flavonoid synthesis and transport were identified. Furthermore, the analysis of 12 carotenoids showed that the content of xanthophylls at 50 days after anthesis was significantly different between the four pepper varieties, which was resulted from the differential expressions of genes downstream of the carotenoid pathway. Our results provide new insights into the understanding of the synthesis and accumulation of flavonoids and carotenoids in pepper fruit.


Assuntos
Capsicum/metabolismo , Capsicum/química , Carotenoides/metabolismo , Cor , Flavonoides/metabolismo , Metaboloma , Transcriptoma , Verduras/química , Verduras/metabolismo
3.
J Agric Food Chem ; 68(2): 591-602, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31859496

RESUMO

An ultrahigh performance liquid chromatography-electrospray-tandem mass spectrometry method was developed for the determination of 36 phenolic compounds in paprika. The proposed method showed good method performance with limits of quantitation between 0.03 and 50 µg/L for 16 compounds and between 50 µg/L and 1 mg/L for 12 compounds. Good linearity (R2 > 0.995), run-to-run and day-to-day precisions (%RSD values < 12.3 and < 19.2%, respectively), and trueness (relative errors < 15.0%) were obtained. The proposed method was applied to the analysis of 111 paprika samples from different production regions: Spain (La Vera PDO and Murcia PDO) and Czech Republic, each one including different flavor varieties (sweet, bittersweet, and spicy). Phenolic profiles and concentration levels showed to be good chemical descriptors to achieve paprika classification and authentication according to the production region by principal component analysis and partial least squares regression-discriminant analysis. In addition, perfect classification among flavor varieties for Murcia PDO and Czech Republic samples was also obtained.


Assuntos
Capsicum/química , Contaminação de Alimentos/análise , Fenóis/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , República Tcheca , Análise de Componente Principal , Espanha , Especiarias/análise , Espectrometria de Massas em Tandem
4.
Food Microbiol ; 85: 103295, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500701

RESUMO

Fermented red pepper (FRP) sauce has been eaten in worldwide for many years. The salt content and resident microbial community influences the quality of the FRP sauce and may confer health (e.g., probiotics) or harm (e.g., antibiotic resistance genes) to the consumers in some circumstances; however, the salt-mediated alteration of microbial community and antibiotic resistance genes are little known. In this study, a combination of whole genome sequencing and amplicon analysis was used to investigate the changes in microbial community and antimicrobial resistance genes in response to different salt content during red pepper fermentation. While the family Enterobacteriaceae dominated in high-salt (15-25%) samples, Lactobacillaceae quickly became the dominant population in place of Enterobacteriaceae after 24 days in 10% salt samples. Compared to 0.05 antibiotic resistance genes (ARGs) per cell number on average in 10% salt sample, 16.6 ARGs were present in high-salt samples, wherein the bacterial hosts were major assigned to Enterobacteriaceae including genera Enterobacter, Citrobacter, Escherichia, Salmonella and Klebsiella. Multidrug resistance genes were the predominant ARG type. Functional profiling showed that histidine kinase functions were of much higher abundance in high-salt samples and included several osmotic stress-related two-component systems that simultaneously encoded ARGs. These results give first metagenomic insights into the salt-mediated changes in microbial community composition and a broad view of associated antibiotic resistance genes in the process of food fermentation.


Assuntos
Capsicum/química , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Lactobacillaceae/genética , Metagenoma , Microbiota , Cloreto de Sódio/química , Enterobacteriaceae/crescimento & desenvolvimento , Fermentação , Genes Bacterianos , Lactobacillaceae/crescimento & desenvolvimento , Metagenômica , Pressão Osmótica
5.
Huan Jing Ke Xue ; 40(7): 3347-3354, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854737

RESUMO

In a preliminary experiment, 91 pepper varieties were screened, and one variety each with high Cd accumulation (X55), medium Cd accumulation (Daguo 99), and low Cd accumulation (Luojiao 318) were selected to study the effect of different cadmium levels (0, 5, and 10 mg·kg-1 Cd) on cadmium migration and enrichment ability, and its subcellular distribution and chemical form. The results showed that under the stress of Cd, shoot dry weight of pepper plants was in the order X55>17>27. At the same level of Cd, the Cd transfer coefficient of fruit was 17>27 and X55. Cadmium concentrations in each subcellular component of the pepper fruits were 27 > 17 > X55. Cadmium concentration in subcellular component of the roots, stems, leaves, and fruits of the pepper plants was in order of cell wall (F1) > organelle (F2) > cell soluble component (F3). Cadmium was limited in cell wall and plays an important role in detoxification mechanism and resistance of Cd in pepper plants. The morphological content of various Cd forms in the pepper fruits of the three varieties increased with the increase of Cd treatment level, in the order CdNaCl > CdHAC > CdR > CdHCl > CdW > CdE. CdNaCl and CdHAC account for a large proportion of Cd in pepper fruits, which may be an important defense mechanism for reducing the biological toxicity of Cd.


Assuntos
Cádmio/química , Capsicum/química , Frutas/química , Folhas de Planta/química , Raízes de Plantas/química
6.
J Agric Food Chem ; 67(44): 12219-12227, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31613626

RESUMO

Quantification, using an accurate analytical approach, of capsinoids and capsaicinoids was performed on three chili pepper (Capsicum spp.) genotypes: "Chiltepín", "Tampiqueño 74", and "Bhut Jolokia" at various stages of fruit development. The accumulation of capsinoids, in all these peppers started between 10 to 20 days post-anthesis (dpa), increased and reached the highest capsinoid amount at 40 dpa, and then decreased until 60 dpa. Conversely, capsaicinoids could already be determined at 10 dpa in "Bhut Jolokia" and their accumulation pattern was different from that of the capsinoids in this genotype. The capsiate/dihydrocapsiate ratio presented a higher variation between genotypes and developmental stages than the capsaicin/dihydrocapsaicin ratio. Capsinoid ratios (4-24%) and Pun1/pAMT genotyping were determined. These results provide information on the progress of the accumulation of capsinoids in the aforementioned pungent and superhot cultivars and could support future breeding studies toward the understanding of the factors affecting their accumulation.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/metabolismo , Capsicum/genética , Capsicum/metabolismo , Aromatizantes/metabolismo , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Alelos , Sequência de Aminoácidos , Capsaicina/análise , Capsicum/química , Capsicum/crescimento & desenvolvimento , Aromatizantes/análise , Frutas/química , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Genótipo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
7.
J Agric Food Chem ; 67(43): 11848-11859, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31600442

RESUMO

To decrease the application dose of thiamethoxam (TMX) to control the pepper whitefly (Bemisia tabaci Q), the deposition, dissipation, metabolism, and field efficacy of TMX were investigated in a pepper (Capsicum annuum var. grossum)-planted ecosystem using eight types of nozzles at six concentrations (56.25, 41.25, 26.25, 21.0, 15.75, and 10.5 g a.i./hm2). The initial deposition amount of TMX in the pepper plant first increased and then decreased with increasing application dose. The optimum spray conditions of TMX were found to be a droplet size of 200 µm volume median diameter and a spray volume of 350 L/hm2. Moreover, three metabolites, TMX-dm, clothianidin (CLO), and C5H8O2N3SCl, were detected in the pepper-planted system. The dissipation rate of TMX in the pepper-field ecosystem was leaves > stems > fruits > roots > soils. The results revealed the deposition and fate of TMX in the pepper-field ecosystem, and the application dose could be reduced by 20% based on the minimum recommended dose for controlling pepper whitefly.


Assuntos
Capsicum/química , Inseticidas/química , Tiametoxam/química , Animais , Capsicum/metabolismo , Ecossistema , Frutas/química , Frutas/metabolismo , Inseticidas/metabolismo , Cinética , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Solo/química , Tiametoxam/metabolismo
8.
J Food Sci ; 84(10): 3018-3026, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31546288

RESUMO

The effects of visual cues on familiarity, expected heat intensity, liking of appearance, emotional and wellness responses, and purchase intent (PI) before and after disclosing information associated with red chili powders were determined using a 3-point scale, a 15-cm line scale, a 9-point hedonic scale, a 15-cm line scale, and a binomial scale, respectively. In this study, consumers only visually evaluated red chili powder samples without sniffing nor tasting. Eight chili powders were prepared according to a 23 factorial design: roasted (Ro) compared with unroasted (Un); whole pod with seeds (Wh) compared with seedless (Sl); coarsely (Cr) compared with finely ground (Gr). Thai consumers (N = 230) were generally more familiar with samples having coarse particles and more reddish color (lower hue angle and higher a* values) than samples having finely ground particles and less reddish/more yellowish color (higher hue angle and lower a* values). The expected heat intensity and liking scores for appearance were lower for samples with higher hue values, particularly RoWhGr and RoSIGr samples. All scores for emotion/wellness terms, except curious, were generally higher for samples with lower hue angle and higher a* values (redness). The consumer familiarity to the appearance of the samples influenced expected heat intensity, liking of appearance, and emotion/wellness responses. PI increased by >10% after presenting "organic," "aflatoxin free," and "organic and aflatoxin free" product statements to consumers. Results showed that familiarity, overall liking of appearance, color liking, fine particles liking, and healthy as well as wild terms were significant predictors for PI (odds ratio = 1.282, 1.519, 1.314, 1.158, 1.056, and 0.939, respectively) of red chili powders. PRACTICAL APPLICATION: This study showed that consumer familiarity to the appearance (visual cues) of red chili powder affected expected heat intensity, liking of appearance, and emotion/wellness responses, which, in turn, affected purchase intent (PI). Samples with more reddish color and coarse particles were perceived to be more familiar than those with more yellowish color and finer particles. Familiarity, overall liking of appearance, color liking, fine particles liking, and healthy and wild terms were significant predictors for PI of chili power. The results demonstrated the importance of visual cues on the consumers' expectation and PI of red chili powder, thus offering valuable information for manufacturers.


Assuntos
Capsicum/economia , Comportamento do Consumidor/economia , Adulto , Capsicum/química , Cor , Sinais (Psicologia) , Emoções , Feminino , Humanos , Intenção , Masculino , Pessoa de Meia-Idade , Motivação , Pós/análise , Paladar
9.
Chem Biodivers ; 16(10): e1900381, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31403756

RESUMO

The variability in the phytochemical concentrations of Capsicum annuum var. glabriusculum has not been extensively analyzed among wild populations and ecologic niches in its phylogeographic area. This study aimed to determine the variations in the phytochemical and antioxidant contents of the wild Piquin chili. The total flavonoid content of hydroalcoholic extracts (0.06 to 0.70 mg equivalent of quercetin per gram of dry weight (mg QE/g DW)), free radical-scavenging capacity for 2,2-diphenyl-1-picrylhydrazyl (DPPH. ) radicals (0.55 to 8.55 mm TE/g DW), amount of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+ ) in aqueous extracts (18.13 to 107.6 mm TE/g DW) and pungency (21,760 to 88,476 Scoville heat units) were highly variable. By analyzing the spatial distribution using the first three principal components, correlations between the phytochemical content and the free radical-scavenging capacity (in both extracts) and flavonoid and phenolic contents (in the hydroalcoholic extract) were observed. Consistent with the statistical analysis, the spatial analysis showed intraregional differences in composition patterns, with an emphasis on central and coastal areas. Flavonoid contents, polyphenol contents and free radical-scavenging activity were the phytochemical components that mainly contributed to the diversity of the population.


Assuntos
Compostos de Bifenilo/antagonistas & inibidores , Capsicum/química , Depuradores de Radicais Livres/farmacologia , Compostos Fitoquímicos/farmacologia , Picratos/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidores , Tiazóis/antagonistas & inibidores , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação
10.
Int J Food Microbiol ; 308: 108303, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31437694

RESUMO

Environmental conditions during ripening of dry-cured meat products favour growth of fungal population on their surface. Some of these moulds can produce mycotoxins. Paprika is one of the ingredients usually used in the formulation of raw-cured sausages, and its addition could influence the growth and production of mycotoxins of the moulds present in these products. In this work the effect of Spanish smoked paprika "Pimentón de la Vera" on growth of Aspergillus parasiticus and Penicillium nordicum and production of aflatoxins B1 (AFB1), G1 (AFG1) and ochratoxin A (OTA) respectively, was evaluated. Moulds were grown in a culture medium made from lyophilized fresh pork meat added with 4% salt and different concentrations of Spanish smoked paprika (1, 2 and 3%) at several water activity values (0.98, 0.94 and 0.87) and temperature (20-25 °C), to simulate conditions usually found during ripening of dry-cured meat products. Mould growth was evaluated by measuring the diameter of the colony every 24 h, and the production of mycotoxins by UHPLC-MS/MS every 2 days, during 10 days of incubation. Addition of paprika favours growth of the two mould species tested. However, the synthesis of mycotoxins was reduced at 0.94 and 0.98 aw when at least a 2% of paprika was added. Therefore, the addition of Spanish smoked paprika at 2-3% in the formulations may help to minimize AFs and OTA production in dry-cured meat products such as loins or "chorizo" sausages.


Assuntos
Aflatoxina B1/biossíntese , Aspergillus/crescimento & desenvolvimento , Capsicum/química , Produtos da Carne/microbiologia , Ocratoxinas/biossíntese , Penicillium/crescimento & desenvolvimento , Animais , Aspergillus/metabolismo , Microbiologia de Alimentos , Penicillium/metabolismo , Fumaça , Cloreto de Sódio/análise , Suínos , Espectrometria de Massas em Tandem , Temperatura Ambiente , Água
11.
Molecules ; 24(17)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461894

RESUMO

Doubanjiang, a Chinese traditional fermented red pepper paste, is eaten worldwide for its unique flavor. The objective of this study was to evaluate the aroma quality of doubanjiang using solvent-assisted flavor evaporation (SAFE) and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). A total of 165 volatile compounds, belonging to 13 chemical classes, were identified. Esters and hydrocarbons were the predominant groups. Thirteen aroma-active compounds were detected by AEDA of SAFE and HS-SPME, and their odor activity values (OAVs) were calculated by dividing their concentration by their odor threshold in water. Among them, ethyl isovalerate, ß-damascenone, 3-isobutyl-2-methoxypyrazine (IBMP), and sotolone had the highest OAVs (>1000). In addition, sotolone, methional, ß-damascenone, 3-isobutyl-2-methoxypyrazine, ethyl isovalerate, phenylethyl alcohol and linalool had high flavor dilution (FD) factors. Sotolone, ß-damascenone and 3-isobutyl-2-methoxypyrazine were identified for the first time in doubanjiang and played significant roles in its aroma quality.


Assuntos
Capsicum/química , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa , Ésteres/análise , Fermentação , Hidrocarbonetos/análise , Extratos Vegetais/análise , Microextração em Fase Sólida
12.
Molecules ; 24(15)2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31387219

RESUMO

In order to deactivate the health properties of bioactive compounds, they need to withstand the effects of food processing, their potential release from the food matrix, and remain bio-accessible in the gastrointestinal tract. Bio-actives from different plants are prone to oxidative degradation, and encapsulation is an effective method in improving their stability. In the present study, red pepper waste (RPW), a by-product of vegetable processing industry, was encapsulated in whey protein using spray and freeze-drying techniques. The aim was to evaluate the effects of in vitro gastrointestinal digestion on the release and bioactivity of encapsulated bio-actives, after each digestion step. The results showed that the release of phenolics and carotenoids, as well as antioxidants, anti-hyperglycemic, and anti-inflammatory activities are influenced by pH and intestinal fluid, with pH 7.5 exhibited at higher levels. There was a rapid initial release of carotenoids from whey protein matrices, while a more gradual increase of phenolics was observed, reaching around 50% for both encapsulates first at 6 h and 37 °C, and small intestine conditions. The encapsulation of RPW demonstrated a protective effect against pH changes and enzymatic activities along digestion, and contributed to the increase in bio-accessibility in the gut. Also, the results suggest that encapsulation is an efficient method for valorization of bio-actives from RPW, with improvements in nutrition, color, and bioactive properties.


Assuntos
Capsicum/química , Carotenoides/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Disponibilidade Biológica , Carotenoides/química , Carotenoides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Digestão , Composição de Medicamentos , Trato Gastrointestinal/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Análise Espectral
13.
Food Chem ; 299: 125144, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31323440

RESUMO

Magnetic nanoparticles were synthesised to extract Sudan dyes from chilli powders. The adsorbents used were magnetic ferroferric oxide nanoparticles coated with polystyrene. The extraction procedures for Sudan dyes comprised liquid-solid extraction and magnetic solid phase extraction. The conditions were optimised to achieve efficient magnetic solid phase extraction, including extraction and desorption time, type and volume of the desorption solvent, and the mass of the adsorbents. Repeatability tests showed satisfactory recovery rates of 80.2-115.8%, with a relative standard deviation <3.8%. The results suggested that the proposed extraction method was effective and efficient to extract Sudan dyes from chilli powders. The extraction process was simpler compared with traditional approaches because the adsorbents can be rapidly removed from the sample matrix using a permanent magnet. The use of recyclable adsorbents decreased the cost greatly. Chilli powder samples collected from local markets in Singapore were tested using the proposed method under optimum conditions.


Assuntos
Capsicum/química , Corantes/análise , Contaminação de Alimentos/análise , Nanopartículas de Magnetita/química , Compostos Azo/análise , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Pós/química , Reprodutibilidade dos Testes , Singapura , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos
14.
Artigo em Inglês | MEDLINE | ID: mdl-31294676

RESUMO

The purpose of this study was to investigate pesticide residues in bell peppers from Shandong Province, China. A total of 299 samples were collected from 17 cities in 2016. The concentrations of 26 pesticide residues were determined by gas chromatography with mass spectrometry (GC-MS). The results showed that there were 25 pesticides (15 OPs, 7 PYs, 3 CBs) found in 86 bell pepper samples, and the total number of positives was 120. The total frequency was 28.76%. The detection frequency for OPs, PYs and CBs was 16.39%, 12.37% and 3.01%, respectively. The most frequently detected pesticide was bifenthrin, with the frequency of 5.02%. 5.35% of samples contained pesticide residues above the maximum residue limits (MRLs) set by China. 7.36% of samples contained more than one pesticide. The values of %ADI were below 100, while the %ARfD of carbofuran and methidathion exceeded 100 for children. The cumulative risk was highest for OPs. From the public health point of view, the levels of pesticide residues in bell peppers do not pose a serious health risk to adults, but the acute health risk to children should be paid more attention.


Assuntos
Capsicum/química , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Adulto , Criança , China , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Controle de Qualidade , Medição de Risco , Extração em Fase Sólida
15.
Sensors (Basel) ; 19(13)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277420

RESUMO

Chlorophyll meters are promising tools for improving the nitrogen (N) management of vegetable crops. To facilitate on-farm use of these meters, sufficiency values that identify deficient and sufficient crop N status are required. This work evaluated the ability of three chlorophyll meters (SPAD-502, atLEAF+, and MC-100) to assess crop N status in sweet pepper. It also determined sufficiency values for optimal N nutrition for each meter for pepper. The experimental work was conducted in a greenhouse, in Almería, Spain, very similar to those used for commercial production, in three different crops grown with fertigation. In each crop, there were five treatments of different N concentration in the nutrient solution, applied in each irrigation, ranging from a very deficient to very excessive N supply. In general, chlorophyll meter measurements were strongly related to crop N status in all phenological stages of the three crops, indicating that these measurements are good indicators of the crop N status of pepper. Sufficiency values determined for each meter for the four major phenological stages were consistent between the three crops. This demonstrated the potential for using these meters with sufficiency values to improve the N management of commercial sweet pepper crops.


Assuntos
Agricultura/instrumentação , Capsicum/química , Clorofila/análise , Nitrogênio/análise , Irrigação Agrícola , Agricultura/métodos , Produtos Agrícolas/química , Fertilizantes , Nitratos , Espanha
16.
Artigo em Inglês | MEDLINE | ID: mdl-31287378

RESUMO

A rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry method, in conjunction with multiwalled carbon nanotube purification, was developed to determine the mefentrifluconazole levels in grapes, cucumbers, tomatoes, peppers, wheat, maize, eggs, milk, pork, chicken, and fish. After purification, tandem mass spectrometry of mefentrifluconazole required <3.0 min. Matrix-matched external standard curves were used to quantify the residual mefentrifluconazole. The method meets the requirements of the European Union Document SANTE/11813/2017. Quantification was linear between 5 and 500 µg/kg (R2 ≥ 0.9988), and both the intra- and interday relative standard deviations were ≤13.7%. Analyte recovery ranged from 81.5% to 107.6%. The limit of mefentrifluconazole quantification was 5 µg/kg for all matrices. The method successfully detected and quantified mefentrifluconazole that had been applied to cucumbers and tomatoes grown in a test field. These results imply that the proposed method is effective and reliable for detecting mefentrifluconazole residues in plant- and animal-derived foods.


Assuntos
Fluconazol/análogos & derivados , Fluconazol/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Animais , Capsicum/química , Galinhas , Cromatografia Líquida de Alta Pressão , Cucumis sativus/química , Ovos/análise , Peixes , Lycopersicon esculentum/química , Leite/química , Carne Vermelha/análise , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem , Fatores de Tempo , Triticum/química , Vitis/química , Zea mays/química
17.
J Agric Food Chem ; 67(26): 7526-7529, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184887

RESUMO

A limitation of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability (DRSA) due to the presence of pigments and colors in the extracts of plant-based foods was addressed. The pigments present in the test samples absorb in the same wavelength region as the DPPH radicals; this interferes with the elaborate absorbance readings of the DPPH radicals. In this contribution, electron paramagnetic resonance (EPR) spectroscopy for DPPH assay is proposed in order to avoid this limitation. In the EPR-DPPH assay, the underestimation of the radical scavenging abilities of four different pigment-containing extracts was corrected and this reflected up to a 16.1% change compared to the original values. Thus, the EPR-DPPH assay eliminated interference from the pigments coexisting in the reaction medium and improved the accuracy of the DPPH radical scavenging potential of such extracts. The principle of the proposed solution might also be employed in other assays which suffer from pigment interference.


Assuntos
Compostos de Bifenilo/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Depuradores de Radicais Livres/química , Picratos/química , Pigmentos Biológicos/química , Extratos Vegetais/química , Beta vulgaris/química , Capsicum/química , Cor , Rubus/química
18.
Food Chem ; 297: 124977, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253260

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are primarily produced during the incomplete combustion of organic matter. PAHs are suspected endocrine disruptors and possible carcinogenic materials. The major sources of human exposure to PAHs are inhaled fumes and food. The aim of this study was to provide an alternative drying method to mitigate PAH formation in dried red peppers. We prepared dried red pepper samples using air-drying and heat pump-assisted drying methods, and measured the concentrations of four PAHs (PAH4), benzo[a] anthracene (B[a]A), chrysene (CHR), benzo[b]fluoranthene (B[b]F), and benzo[a]pyrene (B[a]P), in the resulting pepper samples. The PAH concentrations ranged from 3.61 to 18.0 µg/kg and from 2.22 to 8.35 µg/kg in the air-dried and heat pump-dried pepper samples, respectively. Overall, the results have shown that dried peppers contain PAH4, that the drying conditions for these contaminants should be optimized for mitigating the PAH formation in dried red peppers.


Assuntos
Capsicum/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Antracenos/análise , Antracenos/metabolismo , Benzo(a)pireno/análise , Benzo(a)pireno/metabolismo , Carcinógenos/análise , Carcinógenos/metabolismo , Crisenos/análise , Crisenos/metabolismo , Dessecação , Fluorenos/análise , Fluorenos/metabolismo , Temperatura Alta , Hidrocarbonetos Policíclicos Aromáticos/análise
19.
Food Chem ; 295: 26-35, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174758

RESUMO

Bell peppers are susceptible to chilling injury (CI). To uncover the metabolism of membrane lipid fatty acids (FAs) accompanying CI, a gas chromatography-mass spectrometry (GC-MS)-based approach was used to quantitatively profile major membrane lipid FAs in bell peppers. RT-qPCR was performed to investigate the expression of the key genes that regulate the synthesis of unsaturated FAs. Additionally, we used microstructural, organoleptic, and physicochemical investigations to monitor the primary physiological metabolism of bell peppers. The study revealed that CI symptoms mostly resulted from the destabilization of the cytomembrane, which was induced by decreasing FA desaturation. Moreover, three times lower level of the double bond index in chilled fruits, than the control, further proved that membrane FA unsaturation can be considered a key factor during CI. In conclusion, this study revealed that the metabolism of membrane lipid FAs is involved in responses to CI.


Assuntos
Capsicum/metabolismo , Ácidos Graxos/metabolismo , Conservação de Alimentos/métodos , Lipídeos de Membrana/metabolismo , Capsicum/química , Capsicum/genética , Ácidos Graxos/análise , Ácidos Graxos Insaturados/genética , Ácidos Graxos Insaturados/metabolismo , Frutas/química , Frutas/genética , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Lipoxigenase/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Temperatura Ambiente
20.
Food Chem ; 295: 466-474, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174783

RESUMO

Physicochemical properties and emulsion stability of octenyl succinic anhydride (OSA)-modified partial waxy rice Baegjinju starches which were made with different OSA additions and the color stability of the encapsulated paprika pigment powder using the OSA starch were investigated. The DSs of the OSA starches ranged from 0.0152 to 0.0269. The band at 3303 cm-1 reduced as the OSA levels increased, but the A-type crystallinity was maintained. The oil absorption and emulsion stability, the short chain (DP6-12) amylopectin, the resistant starch levels, and the peak and final viscosities increased as the OSA levels increased. The encapsulated pigment powder with freeze-drying had higher color stability and better emulsion, and heating stabilities occurred with spray drying and the native pigment. From these results, it is suggested that the OSA-modified Baegjinju rice starch is a good wall material to protect lipophilic carotenoids. The encapsulated pigment powders could be used as stable natural colorants.


Assuntos
Capsicum/química , Oryza/química , Pigmentos Biológicos/química , Amido/análogos & derivados , Amilopectina , Emulsões/química , Liofilização , Extratos Vegetais/química , Pós/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Viscosidade
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