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1.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923662

RESUMEN

This paper presents the analyses of the effect of fiber additives on volatile organic compounds in bread. The bread was baked from wheat flour with the addition of 3% of fruit fiber, following common procedures. After baking, volatile organic compounds contained in the control bread and breads supplemented with cranberry, apple, and chokeberry fiber were determined. The SPME/GC-MS technique was used for the identification of the odor profile, and the electronic nose Agrinose (e-nose) was used to assess the intensity of the aroma. The results of the analyses revealed the profile of volatile organic compounds in each experimental variant, which was correlated with responses of the electronic nose. The results indicate that the volatile compound profile depends on the bread additives used and influences the intensity of bread aroma. Moreover, the profile of volatile organic compounds in terms of their amount and type, as well as the intensity of their interaction with the active surface of the electrochemical sensors, was specific exclusively for the additive in each case.


Asunto(s)
Harina , Compuestos Orgánicos Volátiles , Pan/análisis , Suplementos Dietéticos , Harina/análisis , Frutas , Odorantes , Triticum
2.
Molecules ; 26(4)2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33671906

RESUMEN

Alternaria toxins are emerging mycotoxins whose regulation and standardization are in progress by the European Commission and the European Committee for Standardization. This paper describes a dilute and shoot approach to determine five Alternaria toxins in selected food samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The strategy involves sample extraction with acidified aqueous methanol, followed by a solvent change accomplished via sample evaporation and reconstitution. The quantification is based on isotope dilution, applying all corresponding isotopically labeled internal standards to compensate possible matrix effects of the analysis. The main advantages of the present method over other existing methods includes simple and effective sample preparation, as well as detection with high sensitivity. The five-fold sample dilution can decrease matrix effects, which were evaluated with both external and internal standard methods. The results demonstrated a limit of quantification lower than 1.0 µg/kg for all five analytes for the first time. The newly presented method showed acceptable accuracy (52.7-111%) when analyzing naturally contaminated and spiked standard samples at the described levels. The method was validated for tomato-based and flour samples (wheat, rye, and maize). The absolute recovery ranged from 66.7% to 91.6% (RSD < 10%). The developed method could be an alternative approach for those laboratories that exclude sample cleanup and pre-concentration of state-of-the-art instruments with enhanced sensitivity.


Asunto(s)
Alternaria/química , Harina/análisis , Marcaje Isotópico/métodos , Lycopersicon esculentum/química , Espectrometría de Masas/métodos , Toxinas Biológicas/análisis , Cromatografía Liquida , Control de Calidad , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
3.
Food Chem ; 352: 129323, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691210

RESUMEN

In this study, functional snacks with addition of nanoenapsuated resveratrol were prepared to evaluate the nutraceutical and physical properties. The nanoencapsulated resveratrol was prepared from horse-chestnut (HRP), water-chestnut (WRP) and lotus-stem starch particles (LRP) and added to the wheat flour at the level of 0.4% for preparation of snacks by extrusing process. After extrusion, 43-53% and 5.42% of resveratrol was retained in snacks containing encapsulated and free resveratrol (FRP), respectively. The HRP, WRP and LRP showed significantly less peak viscosities and less elastic behaviour than native product (NP) which can influence the human sensory perception. The shift of few peaks towards higher wavelength and presence of additional peaks at 1384, 1229, 1513 and 1613 cm-1 depicts change in molecular pattern and presence of resveratrol in functional snacks. The functional snacks containing encapsulated resveratrol showed significantly higher antioxidant, anti-diabetic and anti-obesity properties than snacks containing no or free resveratrol.


Asunto(s)
Nanoestructuras/química , Resveratrol/química , Resveratrol/farmacología , Bocadillos , Fármacos Antiobesidad/química , Fármacos Antiobesidad/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cápsulas , Harina/análisis , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Gusto , Triticum/química , Viscosidad
4.
Carbohydr Polym ; 259: 117738, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33674022

RESUMEN

Starch is present in many prepared 'ready-meals' that have undergone processing and/or storage in frozen or chilled state. Hydrothermal processing greatly increases starch digestibility and postprandial glycaemia. Effects of different heating/drying and cooling regimes on amylolysis have received little attention. Hence, we examined the effects of different processing treatments on in vitro digestibility of starch in chickpea flour. Solid-state 13C NMR was used to estimate ordered double-helical structure in the starch. Native starch with 25 % double-helical content was the most resistant to digestion but hydrothermal processing (gelatinisation) resulted in >95 % loss of order and a large increase in starch digestibility. Air-drying of pre-treated flour produced slowly-digestible starch (C∞, 55.9 %). Refrigeration of gelatinised samples decreased ease of amylolysis coincident with increase in double-helical content. Freezing maintained the same degree of digestibility as freshly gelatinised material and produced negligible retrogradation. Chilling may be exploited to produce ready-meals with a lower glycaemic response.


Asunto(s)
Cicer/metabolismo , Harina/análisis , Almidón/metabolismo , alfa-Amilasas/metabolismo , Desecación , Digestión , Almacenamiento de Alimentos , Cinética , Espectroscopía de Resonancia Magnética , Almidón/química
5.
Ann Agric Environ Med ; 28(1): 44-48, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33775066

RESUMEN

INTRODUCTION AND OBJECTIVE: Deoxynivalenol (DON, vomitoxin) and Zearalenone (ZEA) are mycotoxin contaminants of cereals and cereal products that pose a significant threat to food safety. The aim of the study was to investigate the occurrence of DON and ZEA in different organic and conventional unprocessed cereals and cereal products that are available on the Polish agricultural fields and market. A total of 78 unprocessed cereal and cereal product samples of organic and conventional production were sampled from agricultural fields situated in western Poland and from available on the Polish market packaged comercial products produced by different domestic manufacturers. All samples were analyzed for DON and ZEA by HPLC with fluorescence detection (HPLC-FLD). RESULTS: Results. Co-occurrence of DON was detected in cereals from the organic production system, the average content was 285.25 ± 134,04 µg kg -1 and from the conventional system - 373.71 ± 171,20 µg kg -1 , In flour from organic farming, the average DON content was 213.80 ± 151,28 µg kg -1, in conventional flour the average was 336.29 ± 188,90 µg kg -1. The range of DON concentrations in samples of cereal products from organic and conventional farms was detected in 26.3% and 31.6%, whereas the average concentrations of DON in cereal products was 199.60 ± 149.82 µg kg -1 and 387.67 ± 250.24 µg kg -1, respectively. CONCLUSIONS: Mycotoxins contamination seen in organic cereals and cereal products does not statistical differ from that witnessed in their conventional counterparts.


Asunto(s)
Agricultura/métodos , Grano Comestible/química , Grano Comestible/crecimiento & desarrollo , Contaminación de Alimentos/análisis , Alimentos Orgánicos/análisis , Tricotecenos/análisis , Zearalenona/análisis , Harina/análisis , Agricultura Orgánica/métodos , Polonia , Triticum/química , Triticum/crecimiento & desarrollo
6.
Food Chem ; 349: 129155, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33548883

RESUMEN

This study aimed to evaluate cookies made with wheat (0%, 80%, 60%, and 50%) and tigernut flour (0%, 20%, 40%, and 50%) from two different sources. Standard methods were applied to determine the chemical properties, phenolic component, fatty acid composition, mineral content, and sensory properties of cookies. Tigernut flour from both sources was rich in oil, and total and individual phenolics, but with low antioxidant activity compared to wheat flour. The addition of tigernut flour to wheat resulted in increase of the content of bioactive compounds, minerals, and fatty acid contents of cookies. The cookies produced by formulating wheat with tigernut had a comparable organoleptic quality scores to wheat flour cookies. The production of cookies with both wheat and tigernut flour showed that this mixture is an interesting opportunity to have a functional product rich in bioactive compounds and considered satisfactory by consumers.


Asunto(s)
Antioxidantes/análisis , Harina/análisis , Valor Nutritivo , Gusto , Triticum/química , Humanos , Verduras/química
7.
Food Chem ; 348: 129017, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33582448

RESUMEN

Extruded wheat starch (ES) was obtained by a single-screw extruder to determine its effect on the farinograph, structural properties and baking behaviors of wheat dough. XRD analysis showed that increasing extrusion temperature made the crystalline peaks less pronounced due to the partial gelatinization. In terms of FTIR results, the molecular order of extruded starch was lower than that of native starch. The dough development time was decreased from 3.2 min to 2.7 min while the stability time was increased from 14.4 min to 15.5 min, as 70 ES were added. It was accompanied with increasing levels of α-helix and ß-turn transferred from the decreased content of random coil and ß -sheet. These effects in bread were to increase loaf volume and reduced loaf hardness. These results indicated that extruded starch had a good potential for producing a high-quality bread.


Asunto(s)
Culinaria , Harina/análisis , Almidón/química , Triticum/química , Pan/análisis , Dureza , Temperatura
8.
Plant Foods Hum Nutr ; 76(1): 118-124, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33635513

RESUMEN

Wheat grains were germinated at different time (12, 24, 36, and 48 h) and temperature (25, 30, and 35°C) to enhance the functionality of resultant flour. Results revealed that an increase in germination time and temperature enhanced the in vitro digestibility of starch (10.35-42.30 %) and proteins (6.31-44.02 %) owing to their depolymerization by hydrolytic enzymes. Total phenolic and flavonoid content of wheat during germination at variable conditions were enhanced significantly (p < 0.05) from 3.62 to 5.54 mg GAE/g and 32.06 to 54.33 mg QE/100 g, respectively. Germination at elevated temperature (35°C) for a prolonged time (48 h) increased the DPPH RSA by 58.85 %, reducing power by 80.40 % and metal chelating activity by 112.26 % as a result of the structural breakdown of bound phenolics. Increased activity of hydrolytic enzymes also results in a continuous reduction in the viscosity and lightness values of wheat flour. Tailored germination, therefore, can be offered as a tool to increase the nutrient digestibility and bioactive potential of wheat thus resulting in producing the naturally modified flour with enhanced functionality.


Asunto(s)
Harina , Germinación , Antioxidantes , Harina/análisis , Nutrientes , Semillas , Almidón , Triticum
9.
Food Chem ; 349: 129125, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33535111

RESUMEN

This study investigated the effect of germination time on compositional changes and functionality of whole wheat malt flour (WMF) as well as its influence on cookie quality. The results illustrated that malting resulted in decreases of starch, protein, fat and ash, while it increased dietary fiber, carbohydrate and energy. Gel hydration, emulsifying and foaming ability, pasting viscosity decreased significantly, particularly during the first 2 days of germination. Both bound and immobilized water in WMF decreased with increasing germination time while the concentration and antioxidant capacity of extractable and hydrolyzable phenolic compounds (EPP and HPP) increased significantly in WMF and malt-based cookies. Flours changed from an integrated granular to an irregular tousy structure during germination. The incorporation of WMF induced a distorted "honey-like" comb structure to the cookies. Conclusively, controlled germination not only improves the physicochemical, functional properties of WMF but also increases nutrition value and technological performance of malt-based cookies.


Asunto(s)
Antioxidantes/análisis , Germinación , Triticum/química , Triticum/crecimiento & desarrollo , Fibras de la Dieta/análisis , Harina/análisis , Valor Nutritivo , Fenoles/análisis , Almidón/análisis , Agua/química
10.
Food Chem ; 349: 129171, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33582542

RESUMEN

Herein, an innovative ratiometric fluorescence (FL) aptasensor was successfully fabricated for the accurate analysis of zearalenone (ZEN) in corn and barley flour. The ZEN aptamer-modified nitrogen doped graphene quantum dots (NGQDs-apt) and silica sphere-encapsulated cadmium telluride quantum dots (CdTe QDs@SiO2) were directly mixed and applied as ratiometric probes. In the absence of ZEN, mitoxantrone (MTX), which was innovatively introduced as quencher, was captured by NGQDs-apt and its inner filter effect (IFE) on CdTe QDs@SiO2 was inhibited. When ZEN existed, MTX separated from NGQDs-apt and re-dispersed around CdTe QDs@SiO2 owing to the competitive binding of ZEN with its aptamer. As the IFE of free MTX on CdTe QDs@SiO2 recovering, the FL intensity of CdTe QDs@SiO2 was quenched, while the FL intensity of NGQDs-apt was nearly invariant. On this basis, a ratiometric FL aptasensor for ZEN was fabricated, which exhibited outstanding detection performances with a desirable detection limit of 0.32 pg mL-1.


Asunto(s)
Compuestos de Cadmio/química , Productos Agrícolas/química , Grano Comestible/química , Mitoxantrona/química , Puntos Cuánticos/química , Dióxido de Silicio/química , Telurio/química , Zearalenona/análisis , Aptámeros de Nucleótidos , Harina/análisis , Fluorescencia , Grafito , Límite de Detección
11.
Food Chem ; 350: 129204, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33618086

RESUMEN

In this study, the ochratoxin A (OTA) interaction with some metal cations exhibits a quenching effect of the Cu2+, Co2+, and Ni2+ in the OTA intrinsic fluorescence intensity. The property of the OTA fluorescence change in complexation with the Cu2+ has been applied in developing a label-free and selective fluorimetric sensor for fast detection of the OTA trace amounts in wheat flour samples. The achieved color difference map (CDM) based on the spectral profile provides the technical support for the rapid visual sensing of OTA in the wheat flour samples. The feasibility of the hybrid fluorimetric sensor and visual OTA detection in wheat flour samples has been confirmed with the high-performance liquid chromatography (HPLC) method as a standard method. The calculated LOD (0.4 ng g-1) and LOQ (1.2 ng g-1) values of the proposed method are much lower than the maximum permissible limit of OTA value reported by the European Union (5 ng g-1).


Asunto(s)
Granjas , Harina/análisis , Contaminación de Alimentos/análisis , Ocratoxinas/química , Espectrometría de Fluorescencia/métodos , Triticum/química
12.
Food Chem ; 350: 129221, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33618096

RESUMEN

The bioactive compounds of pequi peel flours were characterized. Flavonoid contents ranged from 19.67 to 87.61 mg/100 g, high in comparison to many vegetables described in the literature. Gallic acid (11.52-418.67 mg/100 g), gallate ethyl (2026.75 - 5205.90 mg/100 g), ellagic acid (509.47 - 1630.66 mg/100 g), lutein (0.17-1.36 mg/100 g), ß-carotene (0.82 - 1.49 mg/100 g), and ß-cryptoxanthin (0.07 - 0.11 mg/100 g) were identified by HPLC, contributing to a greater valorization of the pequi peel flours. Phytochemical tests indicated the presence of hydrolyzable tannins and saponins. The detection of these compounds makes the product commercially attractive, in addition to generating value for an agro-industrial residue. The results obtained in this study confirm the multifunctional potential of pequi peel flour as a functional ingredient.


Asunto(s)
Harina/análisis , Malpighiales/química , Ácido Elágico/análisis , Flavonoides/análisis , Frutas/química , Ácido Gálico/análogos & derivados , Ácido Gálico/análisis , Taninos Hidrolizables/análisis
13.
Food Chem ; 350: 129229, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33636619

RESUMEN

A new strategy to mimic antibody for electrochemical recognition and detection of deoxynivalenol (DON) using a highly-sensitive and selective antibody-like sensor based on molecularly imprinted poly(l-arginine) (P-Arg-MIP) on carboxylic acid functionalized carbon nanotubes (COOH-MWCNTs) was proposed. l-arginine as functional monomer was screened to prepare imprinted electrode via its electro-polymerization in the presence of DON onto the surface of COOH-MWCNTs electrode coupled with theoretical calculation. Surface morphology, structural characteristics, and electrochemical properties of P-Arg-MIP/COOH-MWCNTs were characterized by SEM, EDS, FTIR, and CV, respectively. P-Arg-MIP/COOH-MWCNTs displayed relatively high conductivity, high effective surface area, antibody-like molecular recognition and affinity, and a good response towards DON in a linear range from 0.1 to 70 µM with LOD of 0.07 µM in wheat flour samples with satisfactory recovery and feasible practicability in comparison with HPLC. This method provides a promising biomimetic sensing platform for the determination of mycotoxins in food and agro-products.


Asunto(s)
Biomimética/instrumentación , Límite de Detección , Impresión Molecular , Nanotubos de Carbono/química , Péptidos/química , Péptidos/síntesis química , Tricotecenos/análisis , Anticuerpos/inmunología , Electroquímica , Electrodos , Harina/análisis , Tricotecenos/química , Triticum/química
14.
Food Chem ; 351: 129291, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33639427

RESUMEN

Bitterness is a common aversive flavor attribute of foods associated with low consumer acceptance. Untargeted LC-MS flavoromic profiling was utilized to identify endogenous compounds that influence the generation of the bitter compound 9,12,13-trihydroxy-trans-10-octadecenoic acid (pinellic acid) during bread making. A diverse sample set of wheat germplasm was chemically profiled. The corresponding pinellic acid concentrations after dough formation were modeled by orthogonal partial least squares (OPLS) with good fit (R2Y = 0.8) and predictive ability (Q2 = 0.6). The most predictive feature (negatively correlated), postulated to interfere with the biosynthetic pathway, was identified as schaftoside, an apigenin di-C-glycoside. Recombination experiments involving the addition of schaftoside to flour prior to breadmaking resulted in a 26% decrease in pinellic acid formation and significantly lower perceived bitterness intensity in whole wheat bread. This work provides novel understanding of bitter generation pathways in wheat products and new strategies to improve flavor profiles and consumer acceptability.


Asunto(s)
Pan/análisis , Ácidos Grasos Insaturados/metabolismo , Espectrometría de Masas en Tándem , Triticum/química , Agentes Aversivos/análisis , Cromatografía Líquida de Alta Presión , Ácidos Grasos Insaturados/análisis , Harina/análisis , Humanos , Análisis de los Mínimos Cuadrados , Análisis de Componente Principal , Umbral Gustativo , Triticum/metabolismo
15.
Food Chem ; 349: 129178, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33607545

RESUMEN

Chinese steamed breads (CSB) and noodles are staple foods for many people. The production of frozen steamed products and boiled noodles has kept increasing. This is due to the increasing demand of ready-to-eat frozen food products from the market. Frozen storage significantly increases the self-life of the products and reduces the production costs. On the other hand, the freezing and frozen storage lead to quality loss of the frozen products. This review summarizes effects of freezing and frozen storage on diverse quality attributes (e.g., structural and textural properties) of frozen northern-type steamed breads and boiled noodles. Food safety of the frozen products related to the COVID-19 pandemic is discussed. To counteract the quality loss of the frozen products, suitable processing methods, selection of basic ingredients and uses of various food additives can be done. Research gaps to improve the textural, cooking and nutritional quality of frozen CSB and noodles are suggested.


Asunto(s)
Pan/análisis , Harina/análisis , Almacenamiento de Alimentos , Culinaria , Congelación , Humanos , Valor Nutritivo , Vapor
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 252: 119504, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33588361

RESUMEN

With the commercial availability of handheld near-infrared (NIR) spectrometers at significantly reduced costs, novel applications for qualitative and quantitative in-the-field and on-site analysis of such instruments for new user communities are currently reported. In the present study, the feasibility of rapid quantitative analysis of the essential quality parameters protein, wet gluten, moisture, ash, and sedimentation of wheat flour samples with three handheld NIR spectrometers based on different monochromator principles (Linear Variable Filter, Fourier-Transform Technique and Fabry-Perot Tunable Filter) has been investigated. In view of the long-term (two years) measurement and calibration schedule with reference sample batches of significantly varying parameter values, the necessary countermeasures for the important issue of calibration maintenance have been addressed and discussed in detail. Due to the variation of available reference values for the different flour parameters, the total number of reference samples varied between 124 (for sedimentation) and 235 (for moisture). These samples were then split up in a 3/1 calibration/test set ratio. Based on the detailed analysis of the statistical calibration parameters and the prediction accuracy for the test sample sets of the different flour parameters, the performance of the spectrometers under investigation has been compared. Despite instrumental and sampling deficiencies, such as hardware changes and significantly varying sample batches, respectively, during the long-term measurement schedule, the results proved the general suitability of the different handheld NIR spectrometers for the rapid quantitative on-site determination of the essential wheat flour parameters.


Asunto(s)
Harina , Triticum , Calibración , Harina/análisis , Glútenes , Espectroscopía Infrarroja Corta
17.
Carbohydr Polym ; 256: 117518, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33483039

RESUMEN

This study aims to understand the starch molecular structural changes from baking sugar-snap cookies. Changes in the whole-molecule size distribution and chain-length distribution of the parent wheat flour and from final cookie products were measured by size-exclusion chromatography with and without enzymatic debranching, and the results fitted by two biosynthesis-based models. Fraction crystallinity was also analyzed. After cooking, there was a significant decrease in average molecular sizes of amylopectin and in the average lengths of amylose chains, and some starch granules lost birefringence. However, the chain-length distributions of amylopectin showed no noticeable difference, resulting in little change in relative crystallinity and gelatinization temperatures. Both the short-range ordered structure and the periodic lamellar structure were disrupted. This study provides new insight into starch structural changes in sugar-snap cookies after baking, which play an important role in determining final cookie quality. For example, a decrease in size of amylose chains influences cookie sensory properties, and thus can be used as an additional tool for choice of grains.


Asunto(s)
Amilopectina/química , Amilosa/química , Harina/análisis , Azúcares/química , Triticum/química , Birrefringencia , Culinaria/métodos , Cristalización , Humanos , Estructura Molecular
18.
Food Chem ; 348: 129032, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33508598

RESUMEN

Our previous work reported that the brown rice flour prepared by low temperature impact mill possessed excellent physicochemical properties. The performance of brown rice flour in making gluten-free bread was further investigated. It was found that the starch crystal structure was destroyed and the damaged starch content increased as the particle size of brown rice flour decreased. The interaction between the starch and water in the model dough and the matrix structures among the endosperm masses were enhanced as the particle size decreased, making the gluten-free dough more viscoelastic. However, dough made with finer flour was too sticky, which limited the expansion of dough. Gluten-free bread prepared with medium-sized brown rice flour had favorable quality characterized by large specific volume, low hardness, numerous and homogeneous gas cells.


Asunto(s)
Dieta Sin Gluten , Harina/análisis , Calidad de los Alimentos , Oryza/química , Temperatura , Pan/análisis , Dureza , Tamaño de la Partícula , Almidón/química , Agua/química
19.
Food Chem ; 348: 128927, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33493845

RESUMEN

Due to its nutritional value and no gluten, potato flour has recently been used as a new type of material to make steamed bread. However, compared to traditional wheat steamed bread, its shelf life is considerably shorter, the dominant microorganisms and storage properties also differ. High-throughput sequencing combined with molecular biology assay revealed that Bacillus methylotrophic and Bacillus subtilis were the dominant bacteria in the crumb of potato and wheat steamed bread, respectively. Moreover, Meyerozyma, Penicillium chrysogenum, Penicillium citrinum, and Aspergillus parasiticus were the main fungi in the crusts. Ethanol was the most volatile compound in fresh potato and wheat steamed bread. Following storage for 48 h, 2,3-butanediol and 3-hydroxy-2-butanone were established as the most volatile compounds. Although decreased sourness was observed, the specific volume, brightness, and nutritional composition remained nearly unchanged. These findings provide a valuable theoretical basis for the development of potato and wheat steamed bread preservation technologies.


Asunto(s)
Pan/microbiología , Fenómenos Químicos , Valor Nutritivo , Solanum tuberosum/química , Gusto , Triticum/química , Triticum/microbiología , Aspergillus/fisiología , Pan/análisis , Harina/análisis , Glútenes/análisis , Penicillium/fisiología
20.
Food Chem ; 347: 129040, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33484960

RESUMEN

An Ultra High-Performance Liquid chromatography method quadruple time-of-flight mass spectrometry has been developed for the analysis of 11 cyclic polyesters oligomers, following a modified QuEChERS clean-up with alumina/primary secondary amine, in pasta. Target analytes were polyethylene terephthalate (PET) 1st series cyclic dimer to heptamer, polybutylene terephthalate (PBT) dimer to pentamer and a polyurethane oligomer. Standard addition method was applied for the calibration, and the limits of quantification ranged from 3.2 to 17.2 ng g-1. Recoveries ranged from 86.4 to 109.8%, RSDs were lower than 12% for all analytes, and matrix effect never exceeded ± 2.5%. The method was successfully applied to real commercial pasta samples, where the PET 1st series cyclic trimer was the most abundant oligomer, being found in all tested samples. The 1st series PET cyclic dimer and tetramer, as well as 1,4,7-trioxacyclotridecane-8,13-dione, were found in considerable amounts. Traces of the 2nd and 3rd series PET cyclic dimers were also found.


Asunto(s)
Análisis de los Alimentos/métodos , Espectrometría de Masas/métodos , Poliésteres/química , Tereftalatos Polietilenos/química , Óxido de Aluminio/química , Cromatografía Líquida de Alta Presión , Dimerización , Harina/análisis , Poliésteres/análisis , Tereftalatos Polietilenos/análisis , Polimerizacion , Dióxido de Silicio/química
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