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1.
Foods ; 12(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37959126

RESUMEN

The influence of incorporation of post-distillation solid wastes of the aromatic plants (SWAP), oregano, rosemary, lemon balm, and spearmint into wheat breads at 1% and 2% levels on their physicochemical and sensorial properties, and antioxidant and volatile profiles were investigated. SWAP breads had darker crumbs and crust and greener crumbs compared to the control, but rather similar loaf specific volume and textural attributes (crust puncture test and crumb Texture Profile Analysis). Although the mold growth on bread crumb surface was not inhibited by SWAP presence, LC-DAD-MS revealed a large increase in terpenoids, like carnosic acid (all SWAP), carnosol (rosemary) and carvacrol (oregano), phenolic (rosmarinic and salvianolic) acids and flavonoids in bread with SWAP inclusion, leading to enhanced antioxidant capacity (ABST, DPPH and FRAP assays). The distinct aromatic plant flavors were detected in the fortified breads by trained assessors and confirmed by SPME-GC/MS volatile analysis, showing high levels of terpenoids in SWAP breads, like carvacrol (oregano), caryophyllene (rosemary and lemon balm), and carvone (spearmint), and rendering the 2% fortification unacceptable by consumers. Nevertheless, breads with 1% oregano or rosemary waste had similar control overall acceptability scores, indicating that SWAP can be a promising ingredient for developing antioxidant-enriched wheat breads.

2.
Foods ; 12(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37893655

RESUMEN

Eight wines, four semisweet rosé and four sweet red, produced on Kos Island in Greece, were analyzed. Wines produced following different winemaking procedures were characterized based on their physicochemical parameters, total phenolic content, antioxidant activity, and chromatic properties. Moreover, their elemental composition was studied with ICP-OES. Differences were observed among the measurements performed. All of the samples were below the levels set for SO2 content. The sweet red wines had higher alcoholic strength than semisweet rosé ones, and were characterized by a higher yellow proportion. The vinification process significantly affected SO2 levels, phenolics, and antioxidant activity. The red wines were high in Na content, with one sample exceeding the level set by OIV (International Organization of Vine and Wine). The levels of all the other elements related to quality (Fe, Cu, Zn) or safety (Pb, Cd) were far below the limits set. Rosé wines contained less Mg, but were higher in Na than the red ones. The obtained data suggest that sweet and semisweet wines produced with traditional procedures are safe and of high quality, holding antioxidant capacity beneficial to health. The information reported contributes to a better understanding of these types of wines.

3.
Molecules ; 28(18)2023 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-37764444

RESUMEN

Rosemary solid distillation waste (SWR), a by-product of the essential oil industry, represents an important source of phenolic antioxidants. Green technologies such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and accelerated solvent extraction (ASE) of phenolic compounds from SWR were optimized as valorization routes to maximize yield, rosmarinic acid (RMA), carnosol (CARO) and carnosic acid (CARA) contents. Response surface methodology was used in this context, with ethanol concentration (X1), extraction temperature (X2), and time (X3) being the independent variables. A second-order polynomial model was fitted to the data, and multiple regression analysis and analysis of variance were used to determine model fitness and optimal conditions. Ethanol concentration was the most influential extraction parameter, affecting phenolic compounds, while the influence of other parameters was moderate. The optimized conditions were as follows: X1: 67.4, 80.0, and 59.0%, X2: 70, 51, and 125 °C, and X3: 15, 10, and 7 min for MAE, UAE, and ASE, respectively. A comparison of optimized MAE, UAE, and ASE with conventional Soxhlet extraction techniques indicated that ASE provided a higher extraction yield and content of phenolic compounds. However, UAE represented the best process from an environmental point of view, allowing an improved extraction of phenolics from SWR with high energy efficiency and low energy costs.


Asunto(s)
Antioxidantes , Rosmarinus , Antioxidantes/farmacología , Antioxidantes/análisis , Flavonoides/análisis , Solventes , Extractos Vegetales/análisis , Fenoles/análisis , Etanol
4.
J Sci Food Agric ; 103(15): 7362-7373, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37394888

RESUMEN

BACKGROUND: This investigation provides an important insight into Eurasian consumers' food safety beliefs and trust issues influenced by the COVID-19 pandemic. An online survey was conducted in 15 European and Asian countries involving more than 4000 consumers. RESULTS: It has confirmed that different socioeconomic characteristics, cultural aspects and education levels shape food safety perceptions within Eurasian countries. The COVID-19 pandemic influenced their beliefs and trust in food safety, which is relatively low on average. However, it is significantly higher for European consumers (especially European Union ones) compared to their Asian counterparts. Both Asian and European respondents agreed that food fraud and climate changes represent a food safety issue. However, European consumers were less concerned regarding the food safety of genetically modified foods and meat and dairy analogs/hybrids. Asian consumers were, to a greater extent, worried about the risk of getting COVID-19 from food, restaurants, food retail establishments and home food deliveries. CONCLUSION: Eurasian consumers have put their greatest extent of trust, when food safety assurance is concerned, into food scientists and food producers holding a food safety certificate. Broadly, they are uncertain to what extent their federal governments and food inspectors are competent, able and efficient in ensuring food safety. Higher education of Eurasian consumers was followed by increased food safety confidence in all parts of the food chain. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
COVID-19 , Pandemias , Humanos , COVID-19/epidemiología , Inocuidad de los Alimentos , Carne , Encuestas y Cuestionarios
5.
Foods ; 12(8)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37107411

RESUMEN

Besides organic growing, ancient wheats and landraces are attracting the attention of scientists who are reassessing the healthy and dietary properties attributed to them by popular tradition. A total of eleven wheat flours and whole meal samples were analyzed, of which, nine originated from the organic farming of five Greek landraces (one einkorn, one emmer, two durum, and one soft wheat) and a commercial organically grown emmer cultivar. Two commercial conventional flours of 70% and 100% extraction rate were examined for comparison purposes. Chemical composition, micronutrients, phenolic profile, and quantification, and antioxidant activity of all samples were determined. Moreover, dough rheology and breadmaking quality were studied; Flours from local landraces were higher in micronutrients, phenolic content, and antioxidant activity than the commercial samples. The 90% extraction flour of the landrace, besides the highest protein content (16.62%), exhibited the highest content of phenolic acids (19.14 µg/g of flour), whereas the commercial refined emmer flour was the lowest (5.92 µg/g of flour). The same milling of the einkorn landrace also showed a higher specific volume (1.9 mL/g vs. 1.7 mL/g) and lower bread crumb firmness than the whole meal commercial emmer sample (33.0 N vs. 44.9 N). The results of this study showed that the examined Greek wheat landraces could be considered as a possible source of microelements, phenolics, and antioxidants with a beneficial effect in human health, and by using an appropriate breadmaking procedure, they could produce high-quality breads.

6.
Antioxidants (Basel) ; 12(3)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36978797

RESUMEN

The essential oil production of Salvia fruticosa L. generates considerable amounts of post-distillation solid residues (PRES) which are rich in phenolic compounds. In the present work, the recovery of phenolic antioxidants from PRES by using Microwave-Assisted Extraction (MAE) and Ultrasound-Assisted Extraction (UAE) were separately optimized, according to the Box-Behnken experimental design. The optimization was based on extraction yield, total phenolic content (TPC), total flavonoid content (TFC), rosmarinic acid (RMA), carnosol (CARO), carnosic acid (CARA), and antioxidant activity. The optimal processing parameters were 72% and 68% ethanol, a 15- and 10-min extraction time, a 40 °C and 47 °C extraction temperature, and a 1:30 and 1:10 solid-to-solvent ratio, for MAE and UAE, respectively. Results showed that the levels of RMA, CARO, and CARA in UAE extracts were influenced mainly by ethanol concentration, extraction time, and extraction temperature, while MAE extracts were only influenced by the first two factors. Experimenting with the optimal conditions revealed MAE as more effective than UAE in the recovery of RMA and CARA. The experimental values were in good agreement with the predicted ones, indicating model efficacy in MAE and UAE optimization to effectively extract phenolic compounds from PRES for their further application in food and pharmaceutical industries.

7.
Foods ; 12(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38231837

RESUMEN

Cereal grains serve as the cornerstone of global nutrition, providing a significant portion of humanity's caloric requirements. However, the presence of fungal genera, such Fusarium, Penicillium, Aspergillus, and Alternaria, known for their mycotoxin-producing abilities, presents a significant threat to human health due to the adverse effects of these toxins. The primary objective of this study was to identify the predominant fungal contaminants in cereal grains utilized in breadmaking, as well as in flour and bread. Moreover, a systematic review, including meta-analysis, was conducted on the occurrence and levels of mycotoxins in wheat flour from the years 2013 to 2023. The genera most frequently reported were Fusarium, followed by Penicillium, Aspergillus, and Alternaria. Among the published reports, the majority focused on the analysis of Deoxynivalenol (DON), which garnered twice as many reports compared to those focusing on Aflatoxins, Zearalenone, and Ochratoxin A. The concentration of these toxins, in most cases determined by HPLC-MS/MS or HPLC coupled with a fluorescence detector (FLD), was occasionally observed to exceed the maximum limits established by national and/or international authorities. The prevalence of mycotoxins in flour samples from the European Union (EU) and China, as well as in foods intended for infants, exhibited a significant reduction compared to other commercial flours assessed by a meta-analysis investigation.

8.
Antioxidants (Basel) ; 10(12)2021 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-34943119

RESUMEN

Plant solid residues obtained from the essential oil industry represent a rich source of phenolic compounds with bioactive properties to be used in the food and pharmaceutical industries. A selective and sensitive liquid chromatography-mass spectrometry (LC-MS) method was developed for the simultaneous determination of phenolic compounds in solid residues of the Lamiaceae family plants. A total of 48 compounds can be separated within 35 min by using the Poroshell-120 EC-C18 column, and a gradient mobile phase of 0.1% formic acid and acetonitrile with flow rate of 0.5 mL/min; salicylic acid was used as internal standard. The calibration curves showed good linearity in the tested concentration range for each analyte (R2 > 0.9921), while recoveries ranged from 70.1% to 115.0% with an intra-day and inter-day precision of less than 6.63% and 15.00%, respectively. Based on the retention behavior, as well as absorption and mass spectra, 17 phenolic acids, 19 flavonoids and 2 phenolic diterpenes were identified and quantified in the solid residues obtained by distillation of six aromatic plants: oregano, rosemary, sage, satureja, lemon balm, and spearmint. The method constitutes an accurate analytical and quality control tool for the simultaneous quantitation of phenolics present in solid waste residues from the essential oil industry.

9.
Foods ; 10(9)2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34574106

RESUMEN

Gluten-free products have come into the market in order to alleviate health problems such as celiac disease. In this review, recent advances in gluten-free bread are described along with plant-based gluten-free proteins. A comparison with animal-based gluten-free proteins is made reporting on different high protein sources of animal origin. Sea microorganisms- and insect-based proteins are also mentioned, and the optimization of the structure of gluten-free bread with added high protein sources is highlighted along with protein digestibility issues. The latter is an issue for consideration that can be manipulated by a careful design of the mixture in terms of phenolic compounds, soluble carbohydrates and fibres, but also the baking process itself. Additionally, the presence of enzymes and different hydrocolloids are key factors controlling quality features of the final product.

10.
Food Chem ; 344: 128710, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33272764

RESUMEN

Microalgae nutritional and healthy dietary pattern might be affected by processes like breadmaking when used as ingredient. This study aims to determine the role of dough acidification on the nutritional pattern of Chlorella vulgaris enriched breads. Different levels of microalga (1%, 2% and 3%) were incorporated in the recipe in the presence of either 10% sourdough or chemically acidified doughs. Dough and bread characteristics were evaluated. Addition of microalga reduced the slice area and increased the crumb hardness, but it could be counteracted by increasing dough hydration and adapting proofing time. Doughs and breads enriched with microalga had green color. Dough acidification led to softer breads and enhanced the antioxidant activity of enriched breads. Microalgae incorporation increased the protein and ash content of the breads. Microalgae enriched breads made with chemically acidified doughs or sourdoughs had higher Total Phenolic Content and antioxidant activity as assessed by FRAP and ABTS methods.


Asunto(s)
Antioxidantes/análisis , Pan/análisis , Microalgas/metabolismo , Chlorella vulgaris/metabolismo , Calidad de los Alimentos , Dureza , Concentración de Iones de Hidrógeno
11.
Foods ; 9(11)2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33182843

RESUMEN

The antifungal effect of aromatic plants (oregano, thyme, and Satureja) in dry form and as essential oils was evaluated in vitro (in potato dextrose agar (PDA)) and in bread against two phytopathogenic fungi found in food (Aspergillusniger and Penicillium). Gas and liquid chromatography were used to analyze essential oils attained by hydrodistillation of the aerial parts of the aromatic plants and of the dried plant aqueous solutions that were autoclaved for 20 min at 121 °C before analysis. Carvacrol, α-pinene, p-cymene, and γ-terpinene were the main components of the essential oils, whereas carvacrol, rosmarinic and caffeic acids were the main components of the water extracts. In vitro antifungal test results showed that the addition of plants in dry form had great antifungal potential against both fungal strains studied. Penicillium was more sensitive to the presence of aromatic plants than Aspergillus. Among the three plant species tested, thyme was the most potent antifungal against both fungi. For the bread product, all three aromatic plants studied showed inhibitory effects against both fungi. Results presented here suggest that oregano, thyme and Satureja incorporated in a bread recipe possess antimicrobial properties and are a potential source of antimicrobial ingredients for the food industry.

12.
Foods ; 9(11)2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33147689

RESUMEN

Carob flour has been used in the production of a wide range of functional food formulations such as bakery goods either as a natural sweetener or food ingredient that, when roasted, exerts a chocolate/cocoa-reminiscent flavor and color. The aim of the present study was twofold; firstly to study the effect of an increasing incorporation of roasted carob flour (0-70% flour basis) on the quality and sensory attributes of a conventional cocoa cake recipe and secondly to investigate the obtained volatile fraction responsible for the aroma by means of headspace solid phase microextraction (HS-SPME) technique coupled to gas chromatography/mass spectrometry (GC/MS) while comparing it with the control, cocoa-containing cake recipe. Thirty and fifty percent carob flour incorporation rendered cakes with acceptable texture and sensory attributes, comparable to the control cake recipe containing 20% cocoa. Similarity to cocoa aroma was attributed to a great number of odor active compounds mainly belonging to aldehydes, lactones, furan/pyran derivatives, and pyrrole derivatives.

13.
Foods ; 9(11)2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33167304

RESUMEN

The present study is aimed to analyze the composition of microelements in wines prepared by amateur winemakers in Drama region (recognized as Protected Geographical Indication (PGI)), especially the toxic ones, as well as the phenolic content and antioxidant activity of these wines since moderate wine consumption may contribute to health benefits to the consumers. A total of twenty-four wines, comprising sixteen red and eight white, were tested. The micro and macroelements were determined with ICP-OES (Inductively coupled plasma-optical emission spectrometry). Chromatic characteristics of wines and total phenolic and flavonoid compounds as well as their antioxidant activity with three different assays were determined spectrophotometrically. The amateur's wines showed levels of contaminants with toxic metals less than the limits set from the International Organization of Vine and Wine (OIV). Moreover, toxic metals concentrations were comparable to those of European wines. The Principal Component Analysis discriminated wines into white and red and further distinguished the red wine into two groups depending on the Total Flavonoid content, antioxidant activity and color intensity. The moderate consumption of amateur wines can be recommended since their consumption is not harmful to the health, and they contain high amount of phenolics and flavonoids comparable or even higher to that of commercial wines.

14.
Foods ; 9(9)2020 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-32899587

RESUMEN

Cereals have been one of the major food resources for human diets and animal feed for thousands of years, and a large quantity of by-products is generated throughout the entire processing food chain, from farm to fork. These by-products mostly consist of the germ and outer layers (bran) derived from dry and wet milling of the grains, of the brewers' spent grain generated in the brewing industry, or comprise other types obtained from the breadmaking and starch production industries. Cereal processing by-products are an excellent low-cost source of various compounds such as dietary fibres, proteins, carbohydrates and sugars, minerals and antioxidants (such as polyphenols and vitamins), among others. Often, they are downgraded and end up as waste or, in the best case, are used as animal feed or fertilizers. With the increase in world population coupled with the growing awareness about environmental sustainability and healthy life-styles and well-being, the interest of the industry and the global market to provide novel, sustainable and innovative solutions for the management of cereal-based by-products is also growing rapidly. In that respect, these promising materials can be valorised by applying various biotechnological techniques, thus leading to numerous economic and environmental advantages as well as important opportunities towards new product development (NPD) in the food and feed industry and other types such as chemical, packaging, nutraceutical (dietary supplements and food additives), cosmetic and pharmaceutical industries. This review aims at giving a scientific overview of the potential and the latest advances on the valorisation of cereal-based by-products and wastes. We intended it to be a reference document for scientists, technicians and all those chasing new research topics and opportunities to explore cereal-based by-products through a circular economy approach.

15.
J Food Biochem ; 43(11): e13020, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31463977

RESUMEN

The incorporation of aromatic plants of Lamiaceae family (oregano, thyme, and Satureja) in a wheat bread was investigated for the effect on the total phenolics, the profile of phenolics, and their free radical scavenging activities. In addition, the influence on dough and bread quality characteristics such as color, gas cells structure, bread texture, degree of staling, and acceptability to consumers was studied. The volume of the fortified breads with dried aromatic plants was slightly decreased and their crumbs were firmer and darker than that of the control bread, yet sensory testing panelists scored them as more aromatic and better tasting. Aromatic plants increased the content of bioactive and antioxidant compounds in the bread though the baking procedure negatively affected the level of these compounds; incorporation of the herbs in a dry form was more effective. The major phenolics detected were carvacrol, rosmarinic acid, and naringenin which have potential health benefits for the consumer. PRACTICAL APPLICATIONS: The aromatic plants of the Lamiaceae family are very rich in phytochemicals with high antioxidant activity. Wheat grains contain significant levels of natural antioxidants such as ferulic acid, tocopherols, and tocotrienols. In contrast, the content of these phytochemicals in the refined flour that is used for the production of traditional bread is much lower since the bran and embryo fractions rich in those compounds are removed during the milling process. The introduction of phytochemicals in the bread recipe will increase the nutritional quality of the final bread and at the same time increase the daily intake of substances with health benefits since bread is consumed daily. Consumption of breads enriched with aromatic plants could be a new way to deliver valuable phytochemicals to consumers and fulfill the increasing consumers' demand for functional foods.


Asunto(s)
Pan/análisis , Lamiaceae/química , Fitoquímicos/química , Antioxidantes/química , Harina/análisis , Manipulación de Alimentos , Humanos , Valor Nutritivo , Gusto , Triticum/química
16.
Artículo en Inglés | MEDLINE | ID: mdl-31009320

RESUMEN

The main objective of this research was to perform an exposure assessment of aflatoxins intake through consumption of maize products in Serbia, Croatia, and Greece. Food consumption survey of maize-based products has been performed during 2017 in the three countries with at least 1,000 interviewees per country covering their dietary habits and body weight. Values for the concentration of aflatoxins were extracted from available research published in the last ten years. Finally, a Monte Carlo analysis of 100,000 iterations was performed to estimate the intake of aflatoxins from consumption of maize-based products. Results revealed that the estimated average exposure of adults to aflatoxins, from maize consumption, in each of the three countries was between 0.44 ng kg-1 bw day-1 and 5.59 ng kg-1 bw day-1. Margin of exposure values for the mean exposure levels, in all three countries, were between 30 and 389. Estimations for hepatocellular carcinoma cases/year/105 individuals, depending on the HBsAg+ prevalence, were 0.075-0.098, 0.006-0.008 and 0.020-0.026 for Serbia, Croatia and Greece, respectively.


Asunto(s)
Aflatoxinas/análisis , Contaminación de Alimentos/análisis , Zea mays/química , Adulto , Anciano , Croacia , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Serbia , Adulto Joven
17.
Food Chem ; 253: 119-126, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29502810

RESUMEN

Gluten-free breads were developed from rice flour and corn starch at a constant ratio 1:1 with acorn meal addition (5, 15, 25%), at three levels of water (65, 70, 75%). Acorn supplemented gluten free breads better met sensory preference than rice breads in terms of colour (brown hue was enhanced) and were also nutritionally improved in terms of total phenolics. The specific volume of breads significantly decreased with increasing acorn addition while crumb hardness was also increased. SEM images confirmed that the decrease in the ΔH values at low water level (65%) was due to less swelling of starch as observed from large starch granule remnants present after baking. XRD measurements revealed coexistence of "B" and "V" type starch structures. Increasing of acorn concentration enhanced the intensity of FTIR bands at 994, 1016 and 1077 cm-1.


Asunto(s)
Pan/análisis , Harina/análisis , Oryza , Quercus/química , Zea mays , Dieta Sin Gluten , Suplementos Dietéticos , Glútenes/análisis , Dureza , Almidón/química , Agua/análisis
18.
J Chromatogr Sci ; 55(7): 690-696, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334872

RESUMEN

Aflatoxins, deoxynivalenol, ochratoxin A and zearalenone are the most important mycotoxins that everyone on its own, in groups or simultaneously contaminate cereals. The external layers of cereal grains (bran) apart from health promoting ingredients are also the most contaminated part with reference to mycotoxin's presence. Therefore, consumption of a high fiber wheat-based diet represent an increased risk to consumer's health. The objective of this study was to develop a simple and reliable high performance liquid chromatography method for the simultaneous determination of these mycotoxins in wheat bran (WB). A double extraction was applied with phosphate buffered saline/methanol and for the clean-up a multi-immunoaffinity column was utilized. The detection was carried out with diode-array and fluorescence detectors linked with a post-column photochemical reactor. After optimization of the chromatographic conditions, all mycotoxins were eluted within ~26 min. Limits of detection for each mycotoxin (0.12-12.58 µg/kg) were below the maximum levels provisioned by European Union regulations. Good linearity was observed for the analytes (r2 ≥ 0.9980). The recovery of analyzed mycotoxins ranged from 70.2 to 105.8%, with a relative standard deviation <12%. The method was successfully applied to quantify mycotoxins in 34 WB samples obtained after pearling of grains that were collected from different regions of Greece.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Fibras de la Dieta/análisis , Micotoxinas/análisis , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
19.
Food Chem ; 203: 267-275, 2016 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26948614

RESUMEN

The effect of copper ions (0.63-0.16 mM) on the rheological behavior of arabinoxylan (AX) aqueous solutions was investigated. Moreover, the influence of ß-glucan addition (BG, 0.5-3% w/v) on the gelation of mixed AX/BG solutions with and without addition of the peroxidase/H2O2 was examined. Generally, gels formed with inclusion of transition metal-ions differed from those obtained by adding peroxidase/H2O2. Copper ions induced viscosity increase of the AX-solutions and form stronger thermoreversible gels with increasing ion-concentration; optimal gelation was at 15 °C. For added ß-glucan at levels >1%, the lower the concentration and the higher the molecular weight of ß-glucan, the weaker the gelling ability of the mixed AX/BG system treated with peroxidase/H2O2. The polysaccharide-ratio affected both the gelling rate and the network melting temperature, with the ß-glucan itself giving the strongest network. Calorimetry provided evidence for existence of ß-glucan ordered domains in the mixed gel structures of AX/BG1, indicative of phase separation events.


Asunto(s)
Cobre/química , Grano Comestible/química , Geles/química , Triticum/química , Xilanos/química , beta-Glucanos/química , Cationes Bivalentes , Carbohidratos de la Dieta/análisis , Peróxido de Hidrógeno/química , Peso Molecular , Reología , Soluciones , Temperatura , Viscosidad , Agua/química , Xilanos/aislamiento & purificación , beta-Glucanos/aislamiento & purificación
20.
J Sep Sci ; 39(8): 1425-32, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26891772

RESUMEN

A simple, sensitive and accurate analytical method was optimized and developed for the determination of deoxynivalenol and aflatoxins in cereals intended for human consumption using high-performance liquid chromatography with diode array and fluorescence detection and a photochemical reactor for enhanced detection. A response surface methodology, using a fractional central composite design, was carried out for optimization of the water percentage at the beginning of the run (X1, 80-90%), the level of acetonitrile at the end of gradient system (X2, 10-20%) with the water percentage fixed at 60%, and the flow rate (X3, 0.8-1.2 mL/min). The studied responses were the chromatographic peak area, the resolution factor and the time of analysis. Optimal chromatographic conditions were: X1 = 80%, X2 = 10%, and X3 = 1 mL/min. Following a double sample extraction with water and a mixture of methanol/water, mycotoxins were rapidly purified by an optimized solid-phase extraction protocol. The optimized method was further validated with respect to linearity (R(2) >0.9991), sensitivity, precision, and recovery (90-112%). The application to 23 commercial cereal samples from Greece showed contamination levels below the legally set limits, except for one maize sample. The main advantages of the developed method are the simplicity of operation and the low cost.


Asunto(s)
Aflatoxinas/análisis , Grano Comestible/química , Tricotecenos/análisis , Cromatografía Líquida de Alta Presión
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