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1.
Food Chem ; 342: 128161, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33268171

RESUMEN

The industrial currants finishing generates a considerable amount of side-stream (FSS) with great potential for biotechnological exploitation. The chemical composition of FSS generated from the premium quality Vostitsa currants was studied. Its use for wine making (at low temperatures, using both free and immobilized yeast) combined with baker's yeast production (with minor nutrient supplementation), is also proposed. Analysis showed that FSS has a rich volatilome (including Maillard reaction/lipid degradation products), increased antioxidant capacity, and total lipid and phenolic contents, compared to the marketable product (currants). However, acidity levels and the presence of specific volatiles (such as acetate esters and higher alcohols) may be indicative of microbial spoilage. The wines made from FSS were methanol free and contained higher levels of terpenes (indicating hydrolysis of bound forms) and fermentation-derived volatiles, compared to FSS. A preliminary technoeconomic analysis for integrated wine/baker's yeast industrial production, showed that the investment is realistic and worthwhile.


Asunto(s)
Ribes/química , Saccharomyces cerevisiae/crecimiento & desarrollo , Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Antioxidantes/química , Células Inmovilizadas/química , Células Inmovilizadas/metabolismo , Cromatografía Líquida de Alta Presión , Fermentación , Cromatografía de Gases y Espectrometría de Masas , Ribes/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Azúcares/análisis , Tartratos/análisis , Temperatura
2.
Anal Bioanal Chem ; 413(2): 355-363, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33057737

RESUMEN

We developed an analytical procedure for determining the δ13C values of organic acids in sake and wine using solid-phase extraction combined with liquid chromatography/isotope ratio mass spectrometry (LC/IRMS). First, the solid-phase extraction (SPE) procedure was performed and various tests were conducted to extract organic acids from alcoholic beverages using the simulated sake sample. Under the optimal SPE procedure, high recovery rates (96-118%) and good accuracies (≤ 0.7‰) were thus achieved for the simulated sake and wine samples. Next, we determined the δ13C of organic acid (tartaric acid, malic acid, lactic acid, succinic acid) in 9 sake and 11 wine samples. Finally, the δ13C values of lactic acid in nine sake samples suggested that lactic acid had been added during the brewing process. The high correlation between the δ13C values of tartaric acid and malic acid in 11 wine samples was consistent with their common source, grapes. This analytical method may help to identify when organic acids have been added to sake and wine and to elucidate the process of organic acid production therein. Graphical abstract.


Asunto(s)
Bebidas Alcohólicas/análisis , Isótopos de Carbono/análisis , Cromatografía Liquida/métodos , Extracción en Fase Sólida/métodos , Vino/análisis , Azul de Bromotimol/análisis , Isótopos de Carbono/química , Técnicas de Química Analítica , Ácido Láctico/análisis , Malatos/análisis , Reproducibilidad de los Resultados , Solventes , Ácido Succínico/análisis , Tartratos/análisis
3.
Yeast ; 37(9-10): 475-486, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32548881

RESUMEN

The most important oenological characteristics of high-quality sparkling wines are aromatic aspect, taste persistence, perlage, high levels of acidity and low pH. Due to hot climate and reduced rainfall that characterize Sicily region, white grape varieties such as Grillo cultivar cultivated in this area are characterized by very low concentrations of malic and tartaric acids. Grillo cultivar is characterized by an intense production of raceme grapes with low pH and high content of tartaric and malic acids. These fruits possess the chemical properties useful to increase the amounts of acids in the final wines. With this in mind, the present research was carried out to test the ability of four Saccharomyces cerevisiae strains (CS182, GR1, MSE13 and MSE41) to ferment a raceme must with a pH of 2.9 at two concentrations (14° and 16° Babo degree) of total sugars. The inoculation of the strains was performed after a preadaptation at pH 2.5. The chemical parameters and kinetics of the fermentations were monitored. The experimental sparkling base wines were characterized by a very high total acidity with 16-17 g/L of tartaric acid and 9-10 g/L of malic acids. On the other hand, ethanol was detected at low values in the range 9-10% (v/v). The base wine obtained with GR1differed in their high acidity values, whereas trials inoculated with CS182 showed more intense odors and exotic fruit. Experimental wines produced in this study represent an innovative strategy for "blending wines" to produce sparkling wines in dry Mediterranean climate.


Asunto(s)
Ácidos , Fermentación , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/metabolismo , Vitis/química , Vino/análisis , Reactores Biológicos , Malatos/análisis , Malatos/metabolismo , Odorantes/análisis , Saccharomyces cerevisiae/genética , Tartratos/análisis , Tartratos/metabolismo , Gusto , Vino/microbiología
4.
Artículo en Inglés | MEDLINE | ID: mdl-32348199

RESUMEN

The aim of this study was to investigate the effects of carboxymethyl celluloses (CMC) with different structures (viscosity and degree of substitution) on the stability of tartrates as well as the growth mechanism of potassium bitartrate (KHT) crystals. Six CMC samples with different viscosity and degree of substitution were investigated by GPC, XRD and SEM to establish their molecular weight, crystal structure, particle size and molecular morphology. As oenological additives, they were studied in model solution and in Cabernet Sauvignon wine. The tartaric stability and inhibitory efficiency were evaluated by conductivity via mini-contact test and compared with metatartaric acid and mannoproteins commercial additives. The results suggest that under the same degree of substitution (DS), with an increase of viscosity, CMC molecular chains agglomerate and fold, the solubility in the wine decreases, thus the effect of stabilising tartrate deteriorates. Whilst at the same viscosity, with an increase of DS, the charge density of CMC molecules increases and the binding ability of ions increases and thus the stabilising tartrate has an obvious effect. The negative charge on the -COO- groups extended from CMC polymer tends to repulse the HT- group in solution while attracting K+ ions to produce a concentration gradient at the crystal surface. In addition, CMC complexes with K+ ions in solution, reducing the number of K+ ions able to diffuse to the adsorption layer. Generally, CMC-6 with a higher the degree of substitution and lower viscosity had best application effect on tartrate stabilisation, and from the price and application performance, CMC was found to be superior to commercial additives like metatartaric acid and mannoproteins.


Asunto(s)
Tartratos/análisis , Vino/análisis , Carboximetilcelulosa de Sodio/química , Estructura Molecular , Peso Molecular , Tamaño de la Partícula , Propiedades de Superficie , Viscosidad
5.
J Chromatogr A ; 1619: 460946, 2020 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-32059866

RESUMEN

Emulsifiers of the type E 472 are esters of fruit acids and mono- and diacylglycerols (MAG and DAG), which are used to adjust techno-functional properties in various food products. The most dominant representatives of E 472 emulsifiers are acetic acid esters (E 472a), lactic acid esters (E 472b), citric acid esters (E 472c), and mono- and diacetyl tartaric acid esters (E 472e). For the determination of fruit acids, a high-performance liquid chromatography method with ultraviolet light (HPLC-UV) detection was developed. Free and total fruit acids were determined by reversed phase HPLC-UV analysis of untreated and saponified emulsifier extracts with 20 mM potassium hydrogen phosphate buffer (pH 2.6) as isocratic eluent. Limits of quantitation of 0.08-0.27 g free fruit acid/kg emulsifier and 4-14 g total fruit acid/kg granted a reliable method with recoveries for free and total fruit acids between 80 and 100% with relative standard deviations (%RSD) below 4%. For the quantitation of free glycerol by spectrophotometry, an enzymatic assay was optimized for the analysis of E 472 providing reliable results with %RSD values below 9%. In addition, the ash content of E 472 emulsifiers was determined.


Asunto(s)
Cromatografía Líquida de Alta Presión , Emulsionantes/química , Ésteres/análisis , Análisis de los Alimentos/métodos , Frutas/química , Glicerol/análisis , Ácido Cítrico/análisis , Diglicéridos/química , Límite de Detección , Tartratos/análisis
6.
Food Res Int ; 120: 389-398, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31000254

RESUMEN

Physicochemical characteristics and phytochemical profiles of red (Physalis alkekengi L., RP) and yellow (P. pubescens L., YP) Physalis fruits cultivated in three provinces of China were characterized. YP fruits showed significantly lower levels of total organic acids and elevated total sugars than those of RP. A total of 18 compounds was tentatively identified in hydromethanolic extracts of Physalis fruits applying HPLC-DAD-ESI-MSn and HR-ESI-MS. Cinnamoyl and hydroxycinnamoyl conjugates prevailed in both fruits. Diverse mono- and dihexosides of cinnamic, coumaric, caffeic, ferulic, and sinapic acid were found in YP, while RP merely contained feruloyl and sinapoyl hexosides. N,N´-dicaffeoylspermidine isomers were found in YP fruits, whereas N,N´-bis(dihydrocaffeoyl)spermine was exclusively detected in two of the RP samples. Additionally, two HDMF (4-hydroxy-2,5-dimethyl-3(2H)-furanone) hexosides were tentatively identified for the first time in YP. Both RP and YP fruits collected from three different provinces in China showed a significant intraspecific variability regarding their phytochemical profiles, despite their similar morphological fruit traits.


Asunto(s)
Frutas/química , Physalis/química , Fitoquímicos/análisis , Aminoácidos/análisis , Ácido Ascórbico/análisis , China , Cromatografía Líquida de Alta Presión , Ácido Cítrico/análisis , Color , Comportamiento del Consumidor , Ácidos Cumáricos/análisis , Análisis de los Alimentos , Calidad de los Alimentos , Fructosa/análisis , Glucosa/análisis , Dureza , Concentración de Iones de Hidrógeno , Malatos/análisis , Espectrometría de Masas , Ácido Quínico/análisis , Sacarosa/análisis , Tartratos/análisis , Gusto
7.
Urology ; 126: 49-53, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30654140

RESUMEN

OBJECTIVE: To further analyze calcium tartrate tetrahydrate stones after a recent case report described this novel stone. Prior to this, there was only one previously reported occurrence of this stone in a human. This unusual stone composition is not tested for routinely. True prevalence and possible causes of this stone are unknown. MATERIALS/METHODS: During the previous case report, micro-CT and Fourier-transform infrared spectroscopy were used to identify a calcium tartrate tetrahydrate stone. This information was applied to urinary stones with previously unidentified compositions in the Mayo Metals laboratory database between 2010 and March 2018. Two additional stones were identified at our institution. Three patients had medical records available for analysis. RESULTS: Between 2010 and March 2018, 35 calcium tartrate stones in 25 patients were identified in the Mayo database as well as 2 at our institution (37 stones in 27 patients). Thirty stones were pure calcium tartrate with the remainder having elements of more common stones. The average age was 46.3 (±14.7) with a slightly higher incidence in females (17 vs 10). Of the 3 medical records investigated, all 3 were males (average age 48.7), and each reported consumption of an energy supplement (Spark) routinely. CONCLUSION: The true prevalence of this relatively unknown stone remains unclear and additional investigation is warranted. We believe all stone laboratories should have access to the IR spectra for calcium tartrate tetrahydrate. Attention should be paid to possible causes of this stone, particularly with relation to oral supplements, to aid with future prevention and treatment.


Asunto(s)
Tartratos/análisis , Cálculos Urinarios/química , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espectroscopía Infrarroja por Transformada de Fourier , Adulto Joven
8.
Food Chem ; 266: 232-239, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30381180

RESUMEN

A sensitive, fast, and inexpensive square wave voltammetric method using a cobalt phthalocyanine modified carbon paste electrode was developed for simultaneous determination of citric, lactic, malic and tartaric acids in fruit juices. To overcome the strong overlap of voltammetric signals caused by calibrated and uncalibrated constituents, multivariate curve resolution with alternating least squares (MCR-ALS) was used. Data were previous treated for correction of baseline and potential shift. The MCR-ALS calibration models were constructed and evaluated using a validation set obtained from a Taguchi design. The values predicted by the optimized MCR-ALS models were unbiased and no statistically significant difference was observed between proposed and reference methods, applying the paired t-test at a confidence level of 95%. As far as the authors know, a voltammetric method that simultaneously determines four organic acids in complex samples such as fruit juices without any previous pretreatment has not yet been reported in the literature.


Asunto(s)
Ácidos Carboxílicos/análisis , Técnicas Electroquímicas/métodos , Electrodos , Jugos de Frutas y Vegetales/análisis , Calibración , Ácido Cítrico/análisis , Indoles , Ácido Láctico/análisis , Malatos/análisis , Compuestos Organometálicos , Tartratos/análisis
9.
Daru ; 26(2): 155-164, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30361888

RESUMEN

BACKGROUND: The aim of our research work was to investigate the relative potencies of matrix components of tylosin, a multi-component antibiotic, and establishing a quantitative relationship between content and potency of each component. METHODS: The potencies of tylosin matrix components were determined by using three bioassay methods. The content of tylosin components (tylosin A, B, C, and D) in different tylosin samples were determined by using high pressure liquid chromatography (HPLC) technique and their theoretical potencies were calculated. Equivalency of theoretical and microbiological potencies for each sample was evaluated using statistical analysis. RESULTS: The highest amount of tylosin B content was found in tylosin phosphate and tartrate (up to 19%). Tylosin D content in all tylosin samples varied in the range of 0.03 to 18.73%. Tylosin A, B, and C showed similar sensitivity to the Kocuria rhizophila, the test organism in agar-diffusion method, while the potency of tylosin D was 39% of A. In the turbidimetric methods by Staphylococcus aureus, tylosin D and B responses to A component were ranged from 22.5 to 22.8% and 77.3 to 79.3%, respectively, while potencies of tylosin C and A were almost equal. The biopotency conversion factors were not resulted to a single factor, due to the different antibacterial activity of tylosin components. CONCLUSION: Our findings indicated that defining individual limit for the low active matrix components and for the total of other components with similar high activity could improve the accuracy of potency results. Graphical abstract ᅟ.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Tilosina/química , Tilosina/farmacología , Cromatografía Líquida de Alta Presión , Pruebas de Sensibilidad Microbiana , Micrococcaceae/efectos de los fármacos , Nefelometría y Turbidimetría , Staphylococcus aureus/efectos de los fármacos , Tartratos/análisis
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 205: 410-418, 2018 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-30048942

RESUMEN

A novel fluorescent probe 2-(2'-hydroxyphenyl)-4-(phenylethylamino)methyloxazole (HPO) has been synthesized, which performed highly selective and sensitive detection of Zn2+ ion with a discriminating enhancement over the other metal ions. The binding constant was calculated as 3.07 × 103 M-1 with detection limit of 1.22 × 10-6 M in aqueous solution (CH3CN-Tris v/v, 1/1, Tris, 10 mM, pH = 7.4). Moreover, the HPO-Zn2+ complex could serve as an excellent tartrate anion (TA). The detection mode maybe due to TA detach Zn2+ ion from HPO-Zn2+ complex leading to resulting in the release of the free probe HPO. As a result, a logic circuit has also been constructed on the basis of Zn2+ and TA as chemical inputs. Furthermore, fluorescence imaging experiments showed that probe HPO could be used as an effective fluorescent probe for detecting Zn2+ and TA in living cells.


Asunto(s)
Colorantes Fluorescentes/química , Oxazoles/química , Espectrometría de Fluorescencia/métodos , Tartratos/análisis , Zinc/análisis , Límite de Detección , Modelos Lineales
11.
Food Res Int ; 105: 261-270, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29433214

RESUMEN

Postharvest dehydration causes changes in texture, color, taste and nutritional value of food due to the high temperatures and long drying times required. In grape berries, a gradual dehydration process is normally utilized for raisin production and for making special wines. Here we applied a raisin industry-mimicking dehydration process for eleven days at 50°C to intact berry clusters from cv. Sémillon plants, and a set of molecular, cellular and biochemical analyses were performed to study the impact of postharvest dehydration in the primary metabolism. Transcriptional analyses by real time qPCR showed that several aquaporins (VvTIP1;2 and VvSIP1) and sugar transporters (VvHT1, VvSWEET11, VvSWEET15, VvTMT1, VvSUC12) genes were strongly upregulated. Moreover, the study of key enzymes of osmolytes metabolism, including mannitol dehydrogenase (VvMTD) and sorbitol dehydrogenase (VvSDH), at gene expression and protein activity level, together with the transcriptional analysis of the polyol transporter gene VvPLT1, showed an enhanced polyol biosynthesis capacity, which was supported by the detection of sorbitol in dehydrated grapes only. The metabolism of organic acids was also modulated, by the induction of transcriptional and biochemical activity modifications in malate dehydrogenases and malic enzymes that led to organic acid degradation, as demonstrated by HPLC analysis. Taken together, this study showed that primary metabolism of harvested berries was severely influenced in response to dehydration treatments towards lower organic acid and higher sorbitol concentrations, while sugar transporter and aquaporin genes were significantly upregulated.


Asunto(s)
Manipulación de Alimentos/métodos , Frutas , Vitis , Acuaporinas/análisis , Acuaporinas/metabolismo , Desecación , Frutas/química , Frutas/metabolismo , Frutas/fisiología , Calor , Proteínas de Transporte de Monosacáridos/análisis , Proteínas de Transporte de Monosacáridos/metabolismo , Sorbitol/análisis , Sorbitol/metabolismo , Tartratos/análisis , Tartratos/metabolismo , Vitis/química , Vitis/metabolismo , Vitis/fisiología
12.
Anal Chim Acta ; 1008: 29-37, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29420941

RESUMEN

The electrocatalytic oxidation of tartaric acid on a carbon paste electrode modified with cobalt (II)-phthalocyanine was demonstrated and applied to the development of a highly sensitive, simple, fast and inexpensive voltammetric sensor to determine tartaric acid. The electrochemical behavior of the modified electrode was investigated by cyclic and square wave voltammetry, and the effect of experimental variables, such as dispersion and loading of cobalt (II)-phthalocyanine, together with optimum conditions for sensing the analyte by square wave voltammetry were assessed. In addition, the absence of a significant memory effect combined with the ease of electrode preparation led to the development of a sensitive and direct method to determine tartaric acid in wines. Interferences from other low molecular weight organic acids commonly present in wines were circumvented by using a multiway calibration technique, successfully obtaining the second order advantage by modeling voltammetric data with unfolded partial least square with residual bilinearization (U-PLS/RBL). A linear response range between 10 and 100 µmol L-1 (r = 0.9991), a relative prediction error of 4.55% and a recovery range from 96.41 to 102.43% were obtained. The proposed method is non-laborious, since it does not use sample pretreatment such as filtration, extraction, pre-concentration or cleanup procedures.


Asunto(s)
Técnicas Electroquímicas , Indoles/química , Compuestos Organometálicos/química , Tartratos/análisis , Vino/análisis , Calibración , Catálisis , Electrodos , Oxidación-Reducción
13.
Artículo en Inglés | MEDLINE | ID: mdl-29428892

RESUMEN

An activatable fluorescence monitoring platform based on a novel Maillard reaction product from d-glucose and L-arginine was prepared through a facile one-pot approach and applied for simultaneous detection of d-isoascorbic acid and tartaric acid. In this work, the new Maillard reaction product GLA was first obtained, and its fluorescence intensity can be effectively quenched by KMnO4, resulting from a new complex (GLA-KMnO4) formation between GLA and KMnO4. Upon addition of d-isoascorbic acid or tartaric acid, an enhanced fluorescence was observed under the optimumed experimental conditions, indicating a stimuli-responsive fluorescence turn on platform for d-isoascorbic acid or tartaric acid can be developed. The corresponding experimental results showed that this turn on fluorescence sensing platform has a high sensitivity for d-isoascorbic acid or tartaric acid, because the detection limits were 5.9µM and 21.5µM, respectively. Additionally, this proposed sensing platform was applied to simultaneously detection of d-isoascorbic acid and tartaric acid in real tap water samples with satisfactory results.


Asunto(s)
Ácido Ascórbico/análisis , Reacción de Maillard , Espectrometría de Fluorescencia/métodos , Tartratos/análisis , Colorantes Fluorescentes/química , Concentración de Iones de Hidrógeno , Límite de Detección , Permanganato de Potasio/química
14.
Biotechnol Lett ; 39(12): 1859-1863, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28875343

RESUMEN

OBJECTIVE: To investigate the expression and immobilization of recombinant cis-epoxysuccinate hydrolase (ESH), and its application in the biological production of L-(+)-tartaric acid. RESULTS: E. coli BL21 (DE3)/pET11a-ESH (His) was engineered to express recombinant ESH. The enzyme had an activity of 262 U mg-1. The recombinant ESH was immobilized on agarose Ni-IDA matrix with metal ion affinity interaction to improve its thermostability and pH stability. The immobilization efficiency and activity yield were 94 and 95%, respectively. The specific catalytic efficiency of immobilized ESH was 104 mg U-1 h-1 during the continuous enzymatic production process. CONCLUSION: ESH with a histidine tag was immobilized and used for the continuous production of L-(+)-tartaric acid.


Asunto(s)
Enzimas Inmovilizadas/metabolismo , Hidrolasas/metabolismo , Proteínas Recombinantes/metabolismo , Tartratos/metabolismo , Reactores Biológicos , Enzimas Inmovilizadas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Hidrolasas/genética , Ingeniería Metabólica , Proteínas Recombinantes/genética , Tartratos/análisis
15.
Luminescence ; 32(7): 1313-1318, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28512780

RESUMEN

Novel chiral fluorescence sensors L-1 and D-1 incorporating N-Boc-protected alanine and acridine moieties were synthesized. The recognition ability of the sensors was studied by fluorescence titration, 1 H NMR spectroscopy and density functional theory (DFT) calculations. The sensors exhibited good enantioselective fluorescent sensing ability toward enantiomers of tartrate anion for the selected carboxylate anions and formed 1: 1 complexes by multiple hydrogen bonding interactions.


Asunto(s)
Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos , Tartratos/análisis , Acridinas/química , Alanina/química , Aniones/análisis , Ácidos Carboxílicos/química , Técnicas de Química Sintética , Colorantes Fluorescentes/síntesis química , Espectroscopía de Resonancia Magnética , Estereoisomerismo , Tartratos/química
16.
J AOAC Int ; 100(2): 573-575, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28118562

RESUMEN

A rapid method, with minimal sample preparation and no chromatography, was developed for analyzing food samples such as olive oil and pomegranate juice to measure adulteration with cheaper ingredients using the novel Direct Sample Analysis™ (DSA) ion source in conjunction with a time-of-flight (TOF)-MS. In less than 30 s, with minimal sample preparation and method development, adulteration of olive oil and pomegranate juice with cheaper seed oils and fruit juices, respectively, was measured with DSA/TOF-MS.


Asunto(s)
Contaminación de Alimentos/análisis , Jugos de Frutas y Vegetales/análisis , Aceite de Oliva/análisis , Lythraceae , Malatos/análisis , Espectrometría de Masas , Olea , Aceite de Soja/análisis , Tartratos/análisis , Triglicéridos/análisis , Trioleína/análisis
17.
J Sci Food Agric ; 97(8): 2468-2479, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27696425

RESUMEN

BACKGROUND: The hybrid grape cultivar 'Isabel' (Vitis labrusca × V. vinifera) is widely grown in the Black Sea region of Turkey and constitutes an important part of the diet of its inhabitants. Phenological and ampelographic studies of the grape have previously been performed, but there are no data concerning nutrient composition. Its nutrient content needs to be investigated to ascertain its potential economic and nutritional uses in the region. RESULTS: The concentrations (range, g kg-1 fresh weight) of major soluble sugars (fructose 2.08-79.70; glucose 3.71-66.74) increased and those of organic acids (tartaric acid 0.05-6.60; malic acid 2.38-9.92) decreased in the skin and pulp during ripening. The major fatty acid was linoleic acid in the skin (50.13), pulp (18.11) and seed (704), while the main minerals (dry weight) were potassium (2.70-19.70), followed by phosphorus (0.53-3.40) and calcium (0.42-5.90) in the parts. CONCLUSION: Berry maturation and ripening significantly influenced the concentrations of sugars and organic acids the most in the skin and pulp, but did not significantly affect the concentrations of fatty acids and minerals in the 'Isabel' grape. Our findings also suggest an optimal harvest time in terms of levels of the nutrients. © 2016 Society of Chemical Industry.


Asunto(s)
Frutas/crecimiento & desarrollo , Vitis/química , Carbohidratos/química , Aromatizantes/química , Aromatizantes/metabolismo , Frutas/química , Frutas/genética , Frutas/metabolismo , Malatos/análisis , Malatos/metabolismo , Minerales/análisis , Minerales/metabolismo , Valor Nutritivo , Tartratos/análisis , Tartratos/metabolismo , Turquía , Vitis/genética , Vitis/crecimiento & desarrollo , Vitis/metabolismo
18.
Food Chem ; 215: 263-73, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27542475

RESUMEN

The study evaluated fruit quality parameters and chemical properties (soluble solids, pH, total acidity and total sugars content, phenolic compounds and antioxidant activity (ABTS, FRAP and ORAC methods)) of 30 grape cultivars of white, red and pink grape, as 28 interspecific hybrids and 2 Vitis vinifera L. popularly grown in Poland. Some of them were analyzed for the first time. A total of 49 polyphenolic compounds were identified by LC-PDA-QTOF/MS and quantified by UPLC-PDA-FL, as 26 anthocyanins, 9 flavonols and flavons, 7 phenolic acids, 6 flavan-3-ols, and 1 stilbene. The content of total polyphenols ranged from 1037.0 (Cascade cv.) to 5759.1mg/100gdm (Roesler cv.). However, the content of stilbene represented by trans resveratrol-3-glucoside was only 18.5-70.5mg/100gdm. Red grape cultivars like Roesler, Rothay and Swenson Red were characterized by the highest content of bioactive compounds and antioxidant activity (significantly more than 24, 12 and 53mmol TE/100gdm, by ABTS, FRAP and ORAC, respectively). Average total acidity and soluble solids for white (0.95g of tartaric acid in 100gfm and 17.1°Bx, respectively) and for red and pink (0.93g of tartaric acid in 100gfm and 17.4°Bx, respectively) cultivars were not significantly different (p>0.05).


Asunto(s)
Fenoles/análisis , Vitis/química , Antocianinas/análisis , Flavonoles/análisis , Hibridación Genética , Hidroxibenzoatos/análisis , Espectrometría de Masas , Polonia , Polifenoles/análisis , Tartratos/análisis
19.
Food Chem ; 212: 821-7, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27374600

RESUMEN

This work was aimed at optimizing a rapid and reproducible conductivity test for the evaluation of wine tartaric stability, in order to improve the practices for the prevention of tartaric precipitations during bottle aging. The test consists in measuring the drop of conductivity in wines kept under stirring for a fixed time, at low temperature, after the addition of micronized potassium bitartrate crystals (KHT). An experimental design was planned to study three factors affecting the test: temperature, duration and dose of added potassium bitartrate. A standard protocol was defined to produce a micronized potassium bitartrate starting from available commercial products, since the dimensions of the crystals can affect the final conductivity values. After the choice of the best conditions the method was validated. Two different stability thresholds were defined for white wines and for red/rosé wines by comparing the results of the mini-contact test with those of the cold test.


Asunto(s)
Conductometría/métodos , Tartratos/análisis , Vino/análisis
20.
J AOAC Int ; 99(4): 948-956, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27302874

RESUMEN

Aspirin (ASP) and dipyridamole (DIP) in combination is widely used in the prevention of secondary events after stroke and transient ischemic attack. Salicylic acid is a well-known impurity of ASP, and the DIP extended-release formulation may contain ester impurities originating from the reaction with tartaric acid. UV spectral data analysis of the active ingredients in the presence of their main impurities is presented using multivariate approaches. Four chemometric-assisted spectrophotometric methods, namely, partial least-squares, concentration residuals augmented classical least-squares (CRACLS), multivariate curve resolution (MCR) alternating least-squares (ALS), and artificial neural networks, were developed and validated. The quantitative analyses of all the proposed calibrations were compared by percentage recoveries, root mean square error of prediction, and standard error of prediction. In addition, r(2) values between the pure and estimated spectral profiles were used to evaluate the qualitative analysis of CRACLS and MCR-ALS. The lowest error was obtained by the CRACLS model, whereas the best correlation was achieved using MCR-ALS. The four multivariate calibration methods could successfully be applied for the extended-release formulation analysis. The application results were also validated by analysis of the stored dosage-form solution, which showed a susceptibility of DIP esterification in the extended-release formulation. Statistical comparison between the proposed and official methods showed no significant difference.


Asunto(s)
Combinación Aspirina y Dipiridamol/química , Dipiridamol/análogos & derivados , Contaminación de Medicamentos , Inhibidores de Agregación Plaquetaria/química , Tartratos/análisis , Cápsulas , Dipiridamol/análisis , Dipiridamol/síntesis química , Análisis de los Mínimos Cuadrados , Redes Neurales de la Computación , Espectrofotometría , Tartratos/síntesis química
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