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1.
Food Chem ; 312: 126091, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901828

RESUMO

Stinging nettle is an annual plant. This plant is known for applications in folk medicine, and as the human diet. The stinging nettle leaves has been used to obtain extracts, which are expected to be with a high content of biologically active compounds. Prepared microwave extracts were applied in the formulation of the functional products. The article completes preparation of the bread with addition of the stinging nettle leaves and its extract, and bread's composition in phenolic acids, flavonoids, micro elements, and macro elements. The biological activity of the prepared bread samples showed significant antioxidant activity. This was especially true against DPPH radicals. It has been shown that it holds a high cytotoxic activity. Leaves themselves decreased the quality of the bread, while the extract improved the quality. It was sensorially confirmed. The article concluded that the extract substitutes leaves in bread as a product of a high benefit.


Assuntos
Pão/análise , Alimento Funcional , Extratos Vegetais/química , Urtica dioica/química , Antioxidantes/química , Flavonoides/análise , Humanos , Hidroxibenzoatos/química , Micro-Ondas , Folhas de Planta/química
2.
Food Chem ; 313: 126079, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31931423

RESUMO

The aim of this study is to analyze in depth, by means of proton nuclear magnetic resonance, 1H NMR, the changes caused by nixtamalization and tortilla making in the lipid composition of two corn varieties. This technique permits the characterization of not only main but also minor lipid components of both corn and tortilla. Ferulates have been found for the first time among the minor components of these lipids. It has been proved that this processing affects the lipids of both corn varieties in a similar way. The total loss of fatty acids occurs as does partial loss of minor components. Furthermore, a slight oxidation is provoked during this processing as well as a small reduction in the unsaturation degree of the lipids. In spite of this a similar distribution of the different kinds of acyl groups has been found in corn and tortilla within each variety.


Assuntos
Pão/análise , Lipídeos/química , Zea mays/metabolismo , Culinária/métodos , Peroxidação de Lipídeos , Espectroscopia de Prótons por Ressonância Magnética
3.
Food Chem ; 312: 126050, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31896455

RESUMO

The fermentation process is crucial to the production of Chinese steamed bread (CSB). In order to select suitable indicators as the basis for further research of establishing intelligent monitoring method for dough fermentation state, this study investigated the dynamic characteristics of dough during fermentation. Indicators included water mobility and distribution, starch-pasting properties, content of free amino acid (FAA), volatile organic compounds (VOCs) and electronic nose (E-nose) response value. Starch-pasting properties of dough and relaxation time (T21, T22) did not change significantly during the fermentation process (p < 0.05). The VOCs and FAAs of the dough had significant differences (p < 0.05) in different fermentation times, but no rule was established. The E-nose response value to headspace was most suitable to monitor the fermentation of dough. Principal component analysis (PCA) was performed on E-nose data from 75 samples and the results indicated that samples of different fermentation states were accurately classified.


Assuntos
Fermentação , Aminoácidos/análise , Pão/análise , Farinha/análise , Amido/química , Vapor , Compostos Orgânicos Voláteis/análise
4.
Food Chem ; 312: 126038, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31896458

RESUMO

To understand wheat dough protein behavior under dual mixing and thermal treatment, solubility of Mixolab-dough proteins were investigated using nine extraction buffers of different dissociation capacities. Size exclusion high performance liquid chromatography (SE-HPLC) and two-dimensional gel electrophoresis (2-DGE) demonstrated that overall changes of protein fractions and dynamic responses of specific proteins during dough processing were well reflected by their solubility variations. After starch pasting, the abundance of 0.5 M NaCl extractable proteins were decreased except for six protein groups including α-amylase inhibitors and superoxide dismutase (SOD). The solubility loss of glutenin proteins at C3 (32 min; 80 â„ƒ) was mainly ascribed to the un-extractable HMW-GSs, LMW-GSs, globulin and triticin, while the extract yield of α-, ß-, γ-gliadins and avenin-like proteins (ALPs) increased after starch pasting. Differential responses of dough proteins to extraction systems provides the basis for further exploring wheat protein dynamics in processing.


Assuntos
Pão/análise , Farinha/análise , Triticum/química , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel Bidimensional , Gliadina/química , Glutens/química , Solubilidade , Amido/química
5.
J Agric Food Chem ; 68(6): 1525-1535, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31942799

RESUMO

Enrichment of food crops with iodine is an option to alleviate dietary deficiencies. Therefore, foliar iodine fertilizer was applied on wheat and rice, in the presence and absence of the other micronutrients zinc and selenium. This treatment increased the concentration of iodine, as well as zinc and selenium, in the staple grains. Subsequently, potential iodine losses during preparation of foodstuffs with the enriched grains were studied. Oven-heating did not affect the iodine content in bread. Extraction of bran from flour lowered the iodine in white bread compared to wholegrain bread, but it was still markedly higher compared to the control. During subsequent in vitro gastrointestinal digestion, a higher percentage of iodine was released from foods based on extracted flour (82-92%) compared to wholegrain foods (50-76%). The foliar fertilization of wheat was found to be adequate to alleviate iodine deficiency in a population with a moderate to high intake of bread.


Assuntos
Iodo/metabolismo , Oryza/metabolismo , Selênio/metabolismo , Triticum/metabolismo , Zinco/metabolismo , Biofortificação , Pão/análise , Culinária , Fertilizantes/análise , Farinha/análise , Alimentos Fortificados/análise , Temperatura Alta , Humanos , Iodo/análise , Oryza/química , Sementes/química , Sementes/metabolismo , Selênio/análise , Triticum/química , Zinco/análise
6.
J Sci Food Agric ; 100(3): 1238-1245, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696519

RESUMO

BACKGROUND: Maize tortilla staling is a major drawback that affects its commercialization and consumption, and so novel methods for retarding staling are continuously being explored. The present study evaluated the effect of adding a canola oil/candelilla wax oleogel (CWO; 0. 2, 4 and 6 g 100 g-1 ) to a basic masa formulation (water, 60 g 100 g-1 ; nixtamalized maize flour, 40 g 100 g-1 ) on the texture, staling and in vitro starch digestibility of maize tortillas made using a hot plate (200 °C). RESULTS: Textural analysis showed that CWO reduced hardness and increased the tensile strength of tortillas. Fourier transform infrared analysis indicated that the retrogradation of starch chains, quantified in terms of the intensity ratio 1047/1022, was reduced by oleogel incorporation. In vitro starch digestibility tests showed that tortillas containing CWO had lower readily digestible and slowly digestible starch fractions compared to the control tortilla without oleogel. CONCLUSION: The formation of amylose-lipid inclusion complexes and the formation of an oily physical barrier around starch granules were postulated as mechanisms underlying the reduced starch digestibility. © 2019 Society of Chemical Industry.


Assuntos
Pão/análise , Euphorbia/química , Aditivos Alimentares/análise , Óleo de Brassica napus/química , Amido/química , Ceras/análise , Zea mays/química , Digestão , Farinha/análise , Manipulação de Alimentos , Qualidade dos Alimentos , Dureza , Humanos , Compostos Orgânicos/química , Amido/metabolismo , Paladar , Zea mays/metabolismo
7.
J Sci Food Agric ; 100(3): 1048-1055, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31677164

RESUMO

BACKGROUND: Magnetic three-dimensional graphene-based nanoadsorbents have unique characteristics such as large surface area, good thermal and chemical stability, and high adsorption capacity that make them efficient materials in sorbent-based extraction techniques. In this study, four aflatoxins (AFs) were analyzed in bread samples using magnetic three-dimensional graphene as the adsorbent phase in dispersive micro solid-phase extraction. RESULTS AND CONCLUSIONS: In-syringe magnetic sheet solid-phase extraction based on magnetic three-dimensional graphene in tandem with dispersive liquid-liquid microextraction was used for the extraction and preconcentration of the target AFs. The effect of significant parameters of the method was investigated and the optimum conditions were determined as follows: adsorbent dosage, 20 mg; desorption/disperser solvent (methanol) volume, 700 µL; desorption solvent flow rate, 0.7 mL min-1 ; pH, neutral; salt (NaCl) concentration, 10% (w/v); extraction solvent (chloroform) volume, 250 µL; and centrifugation rate (and time), 4000 rpm (5 min). The limits of detection and quantification were in the ranges 0.043-0.083 and 0.14-0.28 µg kg-1 , respectively. The extraction method was followed by the HPLC technique with fluorescence detection and applied to the determination of the AFs in four different Iranian fresh and moldy bread samples. The relative recoveries were in the range 84-107% with relative standard deviations of 3.9-8.6%. © 2019 Society of Chemical Industry.


Assuntos
Aflatoxinas/isolamento & purificação , Pão/análise , Contaminação de Alimentos/análise , Microextração em Fase Líquida/métodos , Magnetismo/métodos , Extração em Fase Sólida/métodos , Adsorção , Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão , Irã (Geográfico) , Extração em Fase Sólida/instrumentação , Seringas
8.
Food Microbiol ; 86: 103349, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703858

RESUMO

Pistachio powder was added to flour or semolina to evaluate its contribution to increase the amount of lysine in bread. Bread production was carried out by sourdough technology using a selected 3-species (Lactobacillus sanfranciscensis/Leuconostoc citreum/Weissella cibaria) lactic acid bacterial (LAB) starter culture. All sourdoughs were subjected to a long-time fermentation (21 h) and showed levels of LAB around 109 CFU/g, indicating the suitability of pistachio powder for lactic fermentation. Yeasts were also detected, in particular in semolina trials. MiSeq Illumina technology was applied to investigate the bacterial composition of sourdoughs evidencing a different distribution of LAB species among the trials with Lactobacillus as major LAB group in almost all sourdoughs. Physicochemical parameters were comparable among the trials. After baking, pistachio powder was found not to influence the height of the breads, but pistachio breads were more firm than control breads. Color of the breads, void fraction and cell density, were influenced by pistachio powder. The amount of lysine increased consistently thanks to pistachio supplementation which also determined a higher presence of o-xylene, p-cymene and limonene and the appearance of α-pinene and 1-octen-3-ol in breads. Sensory tests showed the best appreciation scores for the breads produced with flour and pistachio powder.


Assuntos
Pão/análise , Aditivos Alimentares/análise , Lactobacillus/metabolismo , Leuconostoc/metabolismo , Lisina/análise , Pistacia/química , Weissella/metabolismo , Pão/microbiologia , Fermentação , Farinha/análise , Aditivos Alimentares/metabolismo , Alimentos Fortificados/análise , Alimentos Fortificados/microbiologia , Humanos , Lisina/metabolismo , Paladar
9.
Food Chem ; 311: 125940, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864187

RESUMO

Wheat (Triticum spp. L.) is an important source of nutrients and bioactive compounds with recognized beneficial effects. Wheat undergoes several processes with the final aim of separating the endosperm from the outer layers, usually discarded. In this study, free and bound phenolic acids (PAs) profile, betaine and choline contents were quantified in six different wheat species (durum and bread wheat, turanicum wheat, einkorn, emmer and spelt), the corresponding milling by-products (bran, middlings, aleurone and I, II and III steps of debranning) and flour/semolina, using UHPLC-MS/MS methods. The bound form of phenolics was the component present in higher concentration (80% of the total, in average) and ferulic acid was the most abundant compounds, representing between 67 and 73 % of total PAs. Among the species, bread wheat grain totalized the highest content of total PAs (1209.31 ± 7.3 µg g-1 d.w.). Betaine and choline are abundantly present in wheat species. In general, the highest content of bioactive compounds was found in bran (3 times higher than whole grains), emphasizing the good nutritional profile of these by-products. The milling process leads to a severe reduction of phenolic acids and methyl-donors in the end-products.


Assuntos
Betaína/análise , Colina/análise , Manipulação de Alimentos/métodos , Hidroxibenzoatos/análise , Triticum/química , Pão/análise , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Farinha/análise , Fenóis/análise , Sementes/química , Espectrometria de Massas em Tandem , Resíduos/análise , Grãos Integrais/química
10.
Food Chem ; 305: 125447, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499289

RESUMO

A novel α-amylase gene (RmAmyA) from Rhizomucor miehei was cloned and expressed in Pichia pastoris. RmAmyA showed 70% amino acid identity with the α-amylase from Rhizomucor pusillus. A high α-amylase activity of 29,794.2 U/mL was found through high cell density fermentation. The molecular mass of RmAmyA was determined to be 49.9 kDa via SDS-PAGE. RmAmyA was optimally active at 75 °C and pH 6.0, and it did not require Ca2+ to improve its activity. It exhibited broad substrate specificity towards amylose, amylopectin, soluble starch, pullulan, and cyclodextrins. High level of maltose (54%, w/w) was produced after liquefied starch was hydrolysed with RmAmyA for 16 h. Moreover, the addition of RmAmyA into Chinese steamed bread resulted in 7.7% increment in the specific volume, and 17.2% and 11.5% reduction in the chewiness and hardness, respectively. These results indicate that RmAmyA might be a potential candidate for applications in the food industry.


Assuntos
Maltose/metabolismo , Rhizomucor/enzimologia , alfa-Amilases/metabolismo , Pão/análise , Indústria Alimentícia , Concentração de Íons de Hidrogênio , Hidrólise , Pichia/metabolismo , Amido/metabolismo , Especificidade por Substrato , Temperatura Ambiente , alfa-Amilases/química , alfa-Amilases/genética
11.
Food Chem ; 306: 125620, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606627

RESUMO

The lactic acid bacteria (LAB) and yeast strains with phytate degrading ability were isolated from Iranian traditional sourdough, and based on the acid and bile tolerance, three LAB and three yeast strains were selected and molecularly identified. In this study, baker's yeast (Saccharomyces cerevisiae) was considered as a positive control strain to investigate the nutritional and technological properties of the isolated strains. All of the identified microorganisms were characterized based on additional probiotic properties and were evaluated for nutritional and technological characteristics. The functional features are associated with degradation of phytate, antioxidant capacity, exopolysaccharides, phenolic compound content and in vitro starch digestion. Among all the tested strains the highest amount of phytase production capacity (1.64 Unit/ml) and lowest phytate content (17.49 mg/5 g) belonged to Kluyveromyces marxianus. According to the results, the bread prepared by using Kluyveromyces aestuarii possessed the highest porosity percentage (70.43%), and the lowest hardness (508.71 g).


Assuntos
Pão/análise , Lactobacillales/metabolismo , Ácido Fítico/metabolismo , Saccharomyces cerevisiae/metabolismo , Triticum/química , 6-Fitase/metabolismo , Pão/microbiologia , Irã (Geográfico) , Lactobacillales/isolamento & purificação , Probióticos , Saccharomyces cerevisiae/isolamento & purificação , Triticum/metabolismo
12.
Food Chem ; 305: 125510, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622804

RESUMO

The fermentation of Triticum dicoccum with sourdough enhances the nutritional aspects of the final product by the enrichment of several compounds with potential medical and biological activity, hence, could improve the health of consumers. This study analyzed the chemical composition of fermented spelt flour from Garfagnana (Province of Lucca, Tuscany) by 1H Nuclear Magnetic Resonance (1H NMR) spectroscopy and its in vitro antioxidant properties by FRAP and DPPH tests. Beyond this, the ex vivo CAA-RBC assay determined the cellular antioxidant activity on human erythrocytes under oxidative condition. Carbohydrate reduction was observed, while amino acids, organic acids and aromatic compounds with potential antioxidant activity increased during the fermentation time. Moreover, both in vitro and ex vivo outcomes showed an improved antioxidant profile. As a possible industrial application, the fermentation process adopted in this research could be reproduced on a large scale for the commercialization of the products by the food industry.


Assuntos
Pão/análise , Fermentação , Triticum/metabolismo , Antioxidantes/metabolismo , Farinha/análise , Humanos , Itália , Espectroscopia de Prótons por Ressonância Magnética
13.
Food Chem ; 306: 125451, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31634767

RESUMO

Gluten-free (GF) breads often lack proteins, minerals and fibres and have an imbalanced energy value, as they are primarily based on flour or starch. To nutritionally fortify GF bread, dietary fibres from milling and fruit processing by-products can be utilized. However, fibre addition changes sensorial, nutritional and also technological properties, such as dough or batter hydration. This review evaluates and compares different methods for quantifying the hydration properties of GF fibres and the resulting batters. Revelations are that the hydration properties of fibres vary greatly, depending on the utilized measuring technique, thus impeding the calculation of the appropriate water amount for GF batter processing. In addition, bran and fibres increase the loss factor tan δ and delay thermal transformation, compromising the specific loaf volume. Finally, operational strategies, such as enzymatic or extrusion treatments are discussed regarding their efficiency to increase water absorption in order to further improve GF bread quality.


Assuntos
Pão/análise , Dieta Livre de Glúten , Fibras na Dieta/análise , Farinha/análise , Frutas/química , Humanos , Amido/análise , Água/química
14.
Food Chem ; 311: 125964, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31865111

RESUMO

Potassium bromate, is an oxidizing agent and one of the best and cheapest dough improvers in the baking industry. Due to its positive effects it plays a major role in the bread-making industry. Potassium bromate has significant effect on food biomolecules, such as starch and protein, as it affects the extent of gelatinization, viscosity, swelling characteristics as well as gluten proteins; it removes the sulfhydryl group and leads to the formation of disulfide linkages and thus improves the bread properties. However, there are many reports elucidating its negative impact on human health. It is deemed as a potential human carcinogen by IARC and classified under class 2B. Due to this, countries across world have either partially or completely banned it. Numerous techniques have evolved to determine the concentration of potassium bromate in bread. This review explains in detail, the effects of potassium bromate on biomolecules, human health, environment and various methods of analysis.


Assuntos
Pão/análise , Bromatos/química , Animais , Bromatos/análise , Bromatos/toxicidade , Carcinógenos/análise , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Espectrometria de Massas , Proteínas de Plantas/química , Amido/química
15.
J Food Sci ; 85(1): 65-76, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31869859

RESUMO

The effect of lipids extraction on protein salvation, pasting, and dough rheological behavior of flours dough from hard wheat (HW), extraordinarily soft wheat (Ex-SW), and medium-hard wheat (MHW) flour was analyzed. The varieties selected had wide variation in grain hardness index (17 to 95). Ex-SW revealed lower tryptophan fluorescent emission and water absorption (WA) than MHW and HW varieties. The change in pasting parameters on defatting was the highest for Ex-SW varieties. Native flour (NF) of HW varieties showed high protein content, pasting and dough strength, and fluorescence intensity in comparison to Ex-SW varieties, while on defatting this was reversed. Protein pattern of defatted flour and NF did not differ significantly. Defatting of flours increased WA and decreased dough stability (DS). The decrease in DS on defatting was more for Ex-SW varieties than others. DS for HW and MHW varieties reduced upon defatting. Defatting significantly increased all mixographic and rheological properties except peak time. Overall, results showed that defatting of flour improved paste and dough strength. PRACTICAL APPLICATION: Higher gluten strength of defatted wheat flour of varied grain hardness has wide applications. Most of the Indian bread wheat varieties possess GluD1 high-molecular-weight glutenin subunit (HMW-GS) allelic composition of (2 + 12), which is not suitable for bread making due to weak gluten strength. Defatting of flours improved the gluten strength of strong and weak flour dough of different wheat varieties irrespective of GluD1 allelic composition for HMW-GS. Defatted flour may be used to improve the baking and cooking performance of dough made from weak wheat. These findings are highly suitable for wheat milling and baked product manufacturing industries.


Assuntos
Farinha/análise , Manipulação de Alimentos/métodos , Triticum/química , Pão/análise , Culinária , Glutens/química , Dureza , Reologia , Triticum/classificação
16.
Food Chem ; 310: 125954, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31841942

RESUMO

In this work, the chemical and physical profile of 5 different bread types (Multicereal bread, Bavaria wheat bread, Wholemeal bread, Rye and Oat bread) were analysed in depth, namely the nutritional profile, individual fatty acids and soluble sugars through GC-FID and HPLC-RI, respectively, as well as the mineral profile, including micro and macroelements. Furthermore, a texture profile analysis was carried out in addition to the measurement of the crust colour. Each bread type showed a distinct profile, with Wholemeal and Bavaria having the lowest calories, and Oat the highest. Multicereal showed the highest amount of unsaturated fatty acids, while Wholemeal and Rye scored the least sodium amounts. The hardest bread was Rye and the easiest to chew were Oat and Bavaria breads. The latter was also the one with the darkest crumb of all the analysed breads. This work shows that bread can be baked to meet the needs and particularities of various kinds of diets.


Assuntos
Avena , Pão , Valor Nutritivo , Secale , Triticum , Pão/análise , Cromatografia Gasosa , Ácidos Graxos/análise , Análise de Alimentos , Qualidade dos Alimentos , Humanos
17.
Food Chem ; 307: 125529, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644982

RESUMO

Ten lactic acid bacteria (LAB) strains of different species isolated from Chinese traditional sourdough were investigated on their volatile compounds in sourdough fermentation. Sourdoughs fermented with different LAB species were analyzed by principal component analysis (PCA) based on their volatiles. Furthermore, the in situ gene expressions of Lactobacillus sanfranciscensis during sourdough fermentation were investigated by using RNA sequencing for the first time. PCA could discriminate between the sourdoughs fermented by homofermentative and heterofermentative LAB, the former containing more aldehydes and ketones with more than 6 carbon atoms, while the latter featuring ethanol and esters. The Lactobacillus plantarum-fermented sourdough was characterized by high C4-C6 volatiles content, while L. sanfranciscensis showed a unique volatile profile without explicit explanatory compounds. The RNA sequencing suggested that, compared to the sourdough fermented for 6 h, L. sanfranciscensis enhanced carbohydrate metabolism and self-protection activities, but decreased cell proliferation in sourdough at 12 h.


Assuntos
Pão/análise , Fermentação , Aromatizantes/metabolismo , Lactobacillus/metabolismo , Transcriptoma , /análise , Aromatizantes/análise , Microbiologia de Alimentos , Lactobacillus/genética , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Análise de Sequência de RNA , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
18.
Int J Food Microbiol ; 313: 108384, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31670259

RESUMO

Aiming at meeting the recommendations of the World Health Organization regarding the total fiber daily intake, an integrate biotechnological approach, combining xylanase treatment and lactic acid bacteria fermentation of milling by-products from pigmented wheat varieties, hull-less barley and emmer was proposed. The effects on the biochemical and nutritional features were investigated. Enhanced radical scavenging activity, increased concentrations of free amino acids (up to three times) and peptides and optimal in vitro protein digestibility (up to ca. 87%) value as well as relevant phytic acid degradation were achieved during bran fermentation. The main nutritional features of each matrix were enhanced and distinguished. Fortified breads were characterized by a concentration in total dietary fibers and protein of ca. 7 and 13% of dry matter, respectively. Compared to wheat bread the addition of pre-fermented brans caused a significant increase in protein digestibility (up to 79%), and a relevant decrease of the predicted glycemic index (ca. 8%) of the fortified bread. According to the results, this study demonstrates the potential of xylanase treatment and lactic acid bacteria fermentation to be used as suitable strategy to include bran in breadmaking, meeting both nutritional and sensory requests of modern consumers.


Assuntos
Pão/análise , Fibras na Dieta/análise , Endo-1,4-beta-Xilanases/química , Hordeum/microbiologia , Lactobacillales/metabolismo , Triticum/microbiologia , Biocatálise , Pão/microbiologia , Fibras na Dieta/metabolismo , Fermentação , Farinha/análise , Farinha/microbiologia , Aditivos Alimentares/análise , Aditivos Alimentares/metabolismo , Humanos , Lactobacillaceae/metabolismo , Valor Nutritivo , Ácido Fítico/análise , Ácido Fítico/metabolismo , Triticum/química , Resíduos/análise
19.
Artigo em Inglês | MEDLINE | ID: mdl-31846858

RESUMO

This paper describes a hydrophilic interaction liquid chromatography tandem mass spectrometric (HILIC-MS/MS) method for determining acrylamide in food. The method primary optimised for gingerbread samples that have high sugar contents. A new sample preparation process was optimized using an experiment design based on a central composition design (CCD). A mixture of acidified aqueous acetonitrile was established as a suitable extraction medium. The extracts were further diluted and separation of acrylamide on TSKgel Amide-80 HILIC column was carried out within 8 min. The method was validated using naturally contaminated quality check (QC) as well as spiked samples. The developed method showed acceptable accuracy (101% - 105%) and precision (2.9% - 7.6%). The limit of quantification was 20 µg/kg. The method was also tested by analysing acrylamide in other food samples (bread, roasted coffee, instant coffee, cappuccino powder and fried potato). The acrylamide concentrations found in samples were between 20 µg/kg and 667 µg/kg, which were lower than the benchmark levels set by the European Union (EU). The main advantage of the newly developed method over the standard methods included the easier sample preparation and faster analysis with reduced ion suppression.


Assuntos
Acrilamida/análise , Pão/análise , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
20.
Lett Appl Microbiol ; 70(1): 48-54, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642537

RESUMO

This study aims to describe the native microbiota of fermented spelt, taking into consideration both lactic acid bacteria (LAB) and yeasts, for which little data are available. Five samples of commercial spelt flour were subjected to spontaneous fermentation to obtain a type I sourdough. A total of 186 LAB and 174 yeast isolates were selected at different refreshment steps and subjected to further analyses. Within LAB, coccal isolates constituted 78·5% of the total LAB, with the dominance of Pediococcus pentosaceus. Although documented before as a component, this is the first report of a spelt sourdough fermentation dominated by this homofermentative LAB, characterized by a high acidification rate, ability to utilize a wide range of carbon sources and to grow in high osmolarity conditions. Yeast communities resulted in four dominant species, Saccharomyces cerevisiae, Wickerhamomyces anomalus, Pichia fermentans and Clavispora lusitaniae. This study highlights for the first time the biodiversity and dynamics of yeast communities involved in sourdough fermentation of spelt. Compared to commercial baker's yeast, autochthonous W. anomalus, P. fermentans and S. cerevisiae isolates show a good performance, and their use could be an advantage for their acquired adaptation to the environment, providing stability to the fermentation process. SIGNIFICANCE AND IMPACT OF THE STUDY: Nowadays, there is a renewed interest in products based on spelt. This 'ancient grain' is a highly nutritional grain; however, its use is limited to bread-making processes, which are not standardized. The low baking and sensory quality of spelt can be overcome through fermentation processes. However, the autochthonous microbiota of spelt sourdough is poorly known. This study highlights the dynamics of microbial communities involved in sourdough fermentation of spelt and provides the basis for the selection of autochthonous cultures, with the aim of improving the nutritional potential of spelt and its rheology and bread-making properties.


Assuntos
Pão/microbiologia , Lactobacillales/metabolismo , Consórcios Microbianos , Triticum/microbiologia , Leveduras/metabolismo , Biodiversidade , Pão/análise , Fermentação , Farinha/microbiologia , Microbiologia de Alimentos , Lactobacillales/classificação , Lactobacillales/genética , Lactobacillales/isolamento & purificação , Triticum/metabolismo , Leveduras/classificação , Leveduras/genética , Leveduras/isolamento & purificação
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