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Vanillin
Selected AbstractsEffects of vanillin and plasticizer on properties of chitosan-methyl cellulose based filmJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Jurmkwan Sangsuwan Abstract Chitosan-methyl cellulose based films which incorporatate vanillin as an antimicrobial agent and polyethylene glycol 400 (PEG) as a plasticizer were developed in this study. The effects of vanillin and plasticizer concentration on mechanical, barrier, optical, and thermal properties of chitosan-methyl cellulose film were evaluated. When the vanillin concentration was increased at a given PEG level, film flexibility decreased while tensile strength increased slightly. Vanillin increased the barrier to oxygen but not water vapor. Increasing vanillin content resulted in less transparency and a more yellowish tint. The bulky nature of vanillin reduced film crystallization. When PEG concentration was increased at a given vanillin level, it resulted in greater film flexibility but reduced film strength. Water vapor permeability (WVP) and oxygen permeability (OP) increased with increase in PEG content. PEG contributed less to the opacity, yellowness, and crystallization of the film than did vanillin. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Directing vanillin production from ferulic acid by increased acetyl-CoA consumption in recombinant Escherichia coli,BIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009Eun-Gyeong Lee Abstract The amplification of gltA gene encoding citrate synthase of TCA cycle was required for the efficient conversion of acetyl-CoA, generated during vanillin production from ferulic acid, to CoA, which is essential for vanillin production. Vanillin of 1.98 g/L was produced from the E. coli DH5, (pTAHEF-gltA) with gltA amplification in 48 h of culture at 3.0 g/L of ferulic acid, which was about twofold higher than the vanillin production of 0.91 g/L obtained by the E. coli DH5, (pTAHEF) without gltA amplification. The icdA gene encoding isocitrate dehydrogenase of TCA cycle was deleted to make the vanillin producing E. coli utilize glyoxylate bypass which enables more efficient conversion of acetyl-CoA to CoA in comparison with TCA cycle. The production of vanillin by the icdA null mutant of E. coli BW25113 harboring pTAHEF was enhanced by 2.6 times. The gltA amplification of the glyoxylate bypass in the icdA null mutant remarkably increased the production rate of vanillin with a little increase in the amount of vanillin production. The real synergistic effect of gltA amplification and icdA deletion was observed with use of XAD-2 resin reducing the toxicity of vanillin produced during culture. Vanillin of 5.14 g/L was produced in 24 h of the culture with molar conversion yield of 86.6%, which is the highest so far in vanillin production from ferulic acid using recombinant E. coli. Biotechnol. Bioeng. 2009;102: 200,208. © 2008 Wiley Periodicals, Inc. [source] Effect of Binary Combinations of Selected Toxic Compounds on Growth and Fermentation of Kluyveromyces marxianusBIOTECHNOLOGY PROGRESS, Issue 3 2004Jose M. Oliva The inhibitory effects of various lignocellulose degradation products on glucose fermentation by the thermotolerant yeast Kluyveromycesmarxianus were studied in batch cultures. The toxicity of the aromatic alcohol catechol and two aromatic aldehydes (4-hydroxybenzaldehyde and vanillin) was investigated in binary combinations. The aldehyde furfural that usually is present in relatively high concentration in hydrolyzates from pentose degradation was also tested. Experiments were conducted by combining agents at concentrations that individually caused 25% inhibition of growth. Compared to the relative toxicity of the individual compounds, combinations of furfural with catechol and 4-hydroxybenzaldehyde were additive (50% inhibition of growth). The other binary combinations assayed (catechol with 4-hydroxybenzaldehyde, and vanillin with catechol, furfural, or 4-hydroxybenzaldehyde) showed synergistic effect on toxicity and caused a 60,90% decrease in cell mass production. The presence of aldehydes in the fermentation medium strongly inhibited cell growth and ethanol production. Kluyveromyces marxianusreduces aldehydes to their corresponding alcohols to mitigate the toxicity of these compounds. The total reduction of aldehydes was needed to start ethanol production. Vanillin, in binary combination, was dramatically toxic and was the only compound for which inhibition could not be overcome by yeast strain assimilation, causing a 90% reduction in both cell growth and fermentation. [source] Anti-sickling effect of MX-1520, a prodrug of vanillin: an in vivo study using rodentsBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2004Chaojie Zhang Summary Vanillin, a food additive, covalently binds with sickle haemoglobin (Hb S), inhibits cell sickling and shifts the oxygen equilibrium curve towards the left. These effects would potentially benefit patients with sickle cell disease (SCD). However, vanillin has no therapeutic effect if given orally because orally administered vanillin is rapidly decomposed in the upper digestive tract. To overcome this problem, a vanillin prodrug, MX-1520, which is biotransformed to vanillin in vivo, was synthesized. Studies using transgenic sickle mice, which nearly exclusively develop pulmonary sequestration upon exposure to hypoxia, showed that oral administration of MX-1520 prior to hypoxia exposure significantly reduced the percentage of sickled cells in the blood. The survival time under severe hypoxic conditions was prolonged from 6·6 ± 0·8 min in untreated animals to 28·8 ± 12 min (P < 0·05) and 31 ± 7·5 min (P < 0·05) for doses of 137·5 and 275 mg/kg respectively. Intraperitoneal injection of MX-1520 to bypass possible degradation in the digestive tract showed that doses as low as 7 mg/kg prolonged the survival time and reduced the percentage of sickled cells during hypoxia exposure. These results demonstrate the potential for MX-1520 to be a new and safe anti-sickling agent for patients with SCD. [source] Synthesis of Schiff Bases from Biphenyl-4-amine and Vanillin, Vanillal, and Their Esters.CHEMINFORM, Issue 8 2007E. A. Dikusar Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Phenolic compounds and some quality parameters of pumpkin seed oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2010Mirjana Andjelkovic Abstract Pumpkin seed oil has become a recognized source of phenolic compounds. The main aim of this paper was to evaluate the concentration of phenolic compounds and their extraction from pumpkin seed oil. The total phenolics content (TPC) measured in the pumpkin seed oil samples ranged from 24.71 to 50.93,mg GAE/kg of oil. The individual phenolics were tyrosol, vanillic acid, vanillin, luteolin and sinapic acid. Hexane and acetone were the best solvents for the washing step, and methanol for the elution of the phenolics in the solid-phase extraction (diol-SPE), whereas bleaching caused a significant increase in the TPC obtained (24.5,30.7%). Additionally, some other oil characteristics were evaluated. The mean oxidative stability of the oils (OSI) was around 4,h, with 5.43,h for the most stable oil. The maximum antioxidant capacity measured by the reduction of the DPPH radical was 62%, which was comparable to 0.16,mM Trolox equivalent. The color of the oil was expressed by L*a*b* coefficients and its hue and saturation. Whereas all samples had similar lightness, their rates of green, red, yellow and blue color were different. Moreover, TPC correlated negatively with lightness, b* and saturation (,0.49, ,0.48, and ,0.43), and positively with a* and hue (0.58 and 0.52). [source] Aroma-active compounds of American, French, Hungarian and Russian oak woods, studied by GC,MS and GC,OFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2008M. Consuelo Díaz-Maroto Abstract Gas chromatography,mass spectrometry (GC,MS) and gas chromatography,olfactometry (GC,O) were used to study aroma-active compounds in extracts of American, French, Hungarian and Russian oak woods. Compounds that presented high odour intensities for the non-toasted oak woods were guaiacol, hexanal, trans -2-nonenal, trans -oak lactone, cis- oak lactone, eugenol, vanillin and trans- isoeugenol, whilst the same compounds, in addition to furfural, 4-methylguaiacol and cis -isoeugenol, proved important in the toasted oaks. Like the oak lactones, cis- and trans- isoeugenol presented woody/oak odours, particularly in the toasted samples. For Hungarian and Russian samples, both characterized by their lower content of oak lactones, trans- and cis- isoeugenol presented higher odour intensities. For this reason, samples of low oak lactone concentrations, such as Hungarian and Russian oak woods, but also containing isoeugenols, can impart woody/oak odours to wines. Copyright © 2008 John Wiley & Sons, Ltd. [source] Olfactory Familiarization and Discrimination in Preterm and Full-Term NewbornsINFANCY, Issue 1 2002Nathalie Goubet The purpose of this study was to observe olfactory detection and discrimination in preterm and full-term newborns. Infants were familiarized for 10 trials with either vanillin or anethole. On each trial, a cotton swab perfumed with one of the odors was slowly moved in front of the baby's nose for 10 sec. For half of the preterm and full-term infants, a new odor was presented after the last familiarization trial (experimental groups). For the other half, the same odor as during familiarization was presented (control groups). Facial and head movements for both populations and heart rates for preterm infants were recorded before, during, and after odor presentation. Preterm infants reacted to the scents by increasing facial actions and heart rate but not head movements. Full-term infants increased facial and head movements. Neither population showed a clear behavioral habituation pattern, but full-term newborns had a significantly reduced facial reactivity on the last familiarization trial compared to preterm infants. Preterm newborns did, however, show cardiac habituation on the last familiarization trial. Preterm and full-term infants presented with a new odor after familiarization increased responding compared to infants presented with the same odor, indicating their ability to discriminate between 2 odors. Infants' reactivity and discrimination to odors indicate preterm and full-term newborns' ability to be attuned to their olfactory environment. [source] The Aerobic Oxidative Cleavage of Lignin to Produce Hydroxyaromatic Benzaldehydes and Carboxylic Acids via Metal/Bromide Catalysts in Acetic Acid/Water MixturesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2009Walt Partenheimer Abstract Roughly 30% of all woody plants is composed of lignin. Five different lignin samples, from wood and bagasse, were oxidized in air with a cobalt/manganese/zirconium/bromide (Co/Mn/Zr/Br) catalyst in acetic acid as a function of time, temperature, pressure, and lignin and catalyst concentrations. 18 products were identified via gas chromatography-mass spectrometry (GC/MS). The most valuable products from lignin were 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid, 4-hydroxy-3-methoxybenzaldehyde (vanillin), 4-hydroxy-3-methoxybenzoic acid (vanillic acid), 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde) and 4-hydroxy-3,5-dimethoxybenzoic acid (syringic acid). 10.9,wt% of the lignin was converted to the aromatic products. By the use of model compounds we demonstrate that 1) the presence of the phenolic functionality on an aromatic ring does inhibit the rate of reaction but that the alkyl group on the ring still does oxidize to the carboxylic acid, 2) that the masking of phenol by acetylation occurs at a reasonable rate in acetic acid, 3) that the alkyl group of the masked phenol does very readily oxidize, 4) that an acetic anhydride/acetic acid mixture is a good oxidation solvent and 5) that a two-step acetylation/oxidation to the carboxylic acid is feasible. [source] Blending of low-density polyethylene with vanillin for improved barrier and aroma-releasing properties in food packagingJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2009R. S. Jagadish Abstract Modification of low-density polyethylene (LDPE) with vanillin to obtain flavored packaging film with improved gas barrier and flavor-releasing properties has been studied. The modification of LDPE with vanillin was monitored by Fourier transform infrared spectroscopy, wherein the appearance of new peaks at 1704.7, 1673.6, and 1597.2 cm,1 indicates the incorporation of vanillin into LDPE matrix. Films of uniform thickness were obtained by the extrusion of modified LDPE. Modified LDPE was found to have significantly higher gas barrier properties and grease resistance. Sensory quality of food products viz, doodhpeda (milk-based solid soft sweet), biscuit, and skimmed milk powder packed in LDPE-vanillin film showed that the doodhpeda sample had clearly perceptible vanilla aroma, whereas biscuit had marginal aroma and skimmed milk powder did not have noticeable aroma. When viewed in the light of imparting desirable vanilla aroma, results of the study indicated that LDPE-vanillin film has better prospects as a packaging material for solid sweets with considerable fat content when stored under ambient conditions. The release of vanilla aroma was further confirmed by gas chromatography,mass spectrometery analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Effects of vanillin and plasticizer on properties of chitosan-methyl cellulose based filmJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Jurmkwan Sangsuwan Abstract Chitosan-methyl cellulose based films which incorporatate vanillin as an antimicrobial agent and polyethylene glycol 400 (PEG) as a plasticizer were developed in this study. The effects of vanillin and plasticizer concentration on mechanical, barrier, optical, and thermal properties of chitosan-methyl cellulose film were evaluated. When the vanillin concentration was increased at a given PEG level, film flexibility decreased while tensile strength increased slightly. Vanillin increased the barrier to oxygen but not water vapor. Increasing vanillin content resulted in less transparency and a more yellowish tint. The bulky nature of vanillin reduced film crystallization. When PEG concentration was increased at a given vanillin level, it resulted in greater film flexibility but reduced film strength. Water vapor permeability (WVP) and oxygen permeability (OP) increased with increase in PEG content. PEG contributed less to the opacity, yellowness, and crystallization of the film than did vanillin. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Skin sensitization, false positives and false negatives: experience with guinea pig assaysJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2010David A. Basketter Abstract The advent of the local lymph node assay (LLNA), and efforts to develop in vitro alternatives for the identification of skin sensitizing chemicals has focused attention on the issue of false positive and false negative results. In essence, the question becomes ,what is the gold standard?' In this context, attention has focused primarily on the LLNA as this is now the preferred assay for skin sensitization testing. However, for many years prior to introduction of the LLNA, the guinea pig maximization test and the occluded patch test of Buehler were the methods of choice. In order to encourage a more informed dialogue about the relative performance, accuracy and applicability of the LLNA and guinea pig tests, we have here considered the extent to which guinea pig methods were themselves subject to false positives and negative results. We describe and discuss here well-characterized examples of instances where both false negatives (including abietic acid and eugenol) or false positives (including vanillin and sulfanilic acid) have been recorded in guinea pig tests. These and other examples are discussed with particular reference to the fabrication of a gold standard dataset that is required for the validation of in vitro alternatives. Copyright © 2010 John Wiley & Sons, Ltd. [source] Physicochemical, Nutritional, and Functional Characterization of Fruits Xoconostle (Opuntia matudae) Pears from Central-México RegionJOURNAL OF FOOD SCIENCE, Issue 6 2010Salvador H. Guzmán-Maldonado Abstract:, Xoconostle cv. Cuaresmeño (Opuntia matudae) has attracted domestic and international industry attention; however, variations of composition from xoconostle structures have not been evaluated. Industries discard the pulp (endocarp) and peel (pericarp) as wastes and utilize the skin (mesocarp), which is the edible portion. The physicochemical, nutritional, and functional characterization of structures from xoconostle pear from 3 major sites of production in Mexico were assessed. Skin yield ranged from 58% to 64% and was higher to that of peel (22% to 24%) and pulp (12% to 18%) yields. pH, °Brix, and acidity were similar among xoconostle structures. Total fiber showed by peel (18.23% to 20.37%) was 2-fold higher than that of skin. Protein and ether extract were higher in xoconostle pulp compared to that showed by peel and skin. Iron content of xoconostle peel (6 to 9.6 mg/100 g, DWB) was higher to that of skin and pulp and prickly pear pulp. Soluble phenols of peel (840 to 863 mg GAE/100 g, DWB) were almost similar to that of skin (919 to 986 mg GAE/100 g, dry weigh basis); meanwhile, ascorbic acid concentration of skin was 2-fold higher compared to that of peel. The phenolic fraction of xoconostle structures consisted of gallic, vanillic, and 4-hydroxybenzoic acids; catechin, epicatechin, and vanillin were also identified by high-performance liquid chromatography,didoe array detection (HPLC-DAD). Xoconostle peel showed higher antioxidant activity (TEAC) compared to that of skin (2-fold) and pulp (6-fold) of commonly consumed fruits and vegetables. The potential of xoconostle peel and pulp for the production of feed or food is promissory. Practical Application:, Outstanding nutritional and functional properties of xoconostle cv. Cuaresmeño fruits are demonstrated. Increased consumption could contribute positively to improve the diet of rural and urban consumers. The high fiber, mineral, and antioxidant components of xoconostle peel and pulp suggest that these fruit structures, which are currently discarded as waste, have promissory use as feed or food by industry. [source] Storage and Cultivar Effects on Shear Compression Values and Esterified Cell Wall Phenolics in CarrotsJOURNAL OF FOOD SCIENCE, Issue 9 2001T. Beveridge ABSTRACT: Phenolics esterified to cell walls in carrots were found to consist primarily of p-hydroxybenzoic acid with minor contributions from ferulic and vanillic acids and vanillin. These compounds could be indexed by standardized measurement of absorbance at 254 nm. As indexed, esterified cell wall phenolics varied widely between carrot cultivars and increased with carrot storage. These increases were not correlated with increased carrot toughness as determined by measurements in a shear compression cell. Carrot texture was unaffected by the levels of esterified cell wall phenolics present in the tissue. [source] The deuteriation of constituents in olive oil and red wine with Nafion, a polymer supported acid catalystJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 14 2001Kellie L. Tuck Abstract A procedure for the deuteriation of a large range of aromatic compounds with phenolic and methoxy substituents has been developed using Nafion, a polymer supported acid catalyst. A range of compounds present in red wine and olive oil were deuteriated using these conditions. This procedure provides a facile route for the labelling of homovanillic alcohol, homovanillic acid, syringic acid, syringaldehyde and vanillin. This method is also applicable for the tritiation of these compounds. Copyright © 2001 John Wiley & Sons, Ltd. [source] Perfumery quaternary diagrams for engineering perfumesAICHE JOURNAL, Issue 8 2009Miguel A. Teixeira Abstract The Perfumery Ternary Diagram (PTD®) methodology predicts the headspace odor character and intensity of fragrant mixtures, applying the concept of odor value (OV) to multi-component systems. This methodology is extended here to quaternary and quinary odorant systems through the use of tetrahedric diagrams. To present this new methodology, the effect of different base notes in quaternary systems of the type (limonene + geraniol + base note + ethanol) and its forming ternary subsystems has been studied. Base notes selected were: vanillin, tonalide, ambrox, and galaxolide. The Perfumery Quaternary Diagrams (PQD) of the mixtures studied show the different headspace odor character, with ambrox and galaxolide dominating most of the composition spectrum (OVmax). The methodology was also applied to the quinary mixture (limonene + geraniol + vanillin + tonalide + ethanol), and the effect of different concentrations of tonalide on the headspace is presented. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] A new methodology for the definition of odor zones in perfumery ternary diagramsAICHE JOURNAL, Issue 8 2006Vera G. Mata Abstract The new methodology called "Perfumery Ternary Diagram" helps perfumers in odor prediction, allowing a fast evaluation of the odor value in the headspace for all possible combinations of a non-ideal perfume liquid mixture with three fragrant components and one or more solvents. In this work, the determination of Perfumery Ternary Points (PTP) and Perfumery Binary Lines (PBL) is described, allowing a complete definition of Perfumery Ternary Diagram (PTD) odor zones, without the need to calculate a large number of points inside the triangle region. The methodology of PTP and PBL determination was applied to the system: limonene, geraniol, vanillin, and ethanol. The effect of solvent,ethanol,on the odor zones, namely on the number of PTP and on the shape of the PBL was studied, as well as the effect of the non-idealities. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source] Prediction of solubility of drugs and other compounds in organic solventsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2010Michael H. Abraham Abstract We have set out a procedure for the prediction of solubilities of drugs and other compounds in a wide range of solvents, based on the Abraham solvation equations. The method requires a knowledge of solubilities of a given compound in a few solvents, as shown by our own experimental data on apocynin, diapocynin, dehydrodivanillin, and dehydrodi(methyl vanillate). The procedure is especially useful for very hydrophobic compounds such as cholesteryl acetate and cholesterol that we give as examples. Other examples include vanillin and 3,4-dichlorobenzoic acid. If the solubility in water is available, then this alone is sufficient to predict solubilities in organic solvents, provided that the Abraham descriptors are available for the compound. Predictions can be made for solubilities in some 85 solvents. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1500,1515, 2010 [source] Coumarins and phenolic fingerprints of oak and Brazilian woods extracted by sugarcane spiritJOURNAL OF SEPARATION SCIENCE, JSS, Issue 21 2009Alexandre Ataide da Silva Abstract A total of 25 sugarcane spirit extracts of six different Brazilian woods and oak, commonly used by cooperage industries for aging cachaça, were analyzed for the presence of 14 phenolic compounds (ellagic acid, gallic acid, vanillin, syringaldehyde, synapaldehyde, coniferaldehyde, vanillic acid, syringic acid, quercetin, trans -resveratrol, catechin, epicatechin, eugenol, and myricetin) and two coumarins (scopoletin and coumarin) by HPLC-DAD-fluorescence and HPLC-ESI-MSn. Furthermore, an HPLC-DAD chromatographic fingerprint was build-up using chemometric analysis based on the chromatographic elution profiles of the extracts monitored at 280,nm. Major components identified and quantified in Brazilian wood extracts were coumarin, ellagic acid, and catechin, whereas oak extracts shown a major contribution of catechin, vanillic acid, and syringaldehyde. The main difference observed among oak and Brazilian woods remains in the concentration of coumarin, catechin, syringaldehyde, and coniferaldehyde. The chemometric analysis of the quantitative profile of the 14 phenolic compounds and two coumarins in the wood extracts provides a differentiation between the Brazilian wood and oak extracts. The chromatographic fingerprint treated by multivariate analysis revealed significant differences among Brazilian woods themselves and oak, clearly defining six groups of wood extracts: (i) oak extracts, (ii) jatobá extracts, (iii) cabreúva-parda extracts, (iv) amendoim extracts, (v) canela-sassafrás extracts and (vi) pequi extracts. [source] RP-HPTLC densitometric determination and validation of vanillin and related phenolic compounds in accelerated solvent extract of Vanilla planifolia,*JOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2007Upendra Kumar Sharma Abstract A simple, fast and sensitive RP-HPTLC method is developed for simultaneous quantitative determination of vanillin and related phenolic compounds in ethanolic extracts of Vanilla planifolia pods. In addition to this, the applicability of accelerated solvent extraction (ASE) as an alternative to microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and Soxhlet extraction was also explored for the rapid extraction of phenolic compounds in vanilla pods. Good separation was achieved on aluminium plates precoated with silica gel RP-18 F254S in the mobile phase of methanol/water/isopropanol/acetic acid (30:65:2:3, by volume). The method showed good linearity, high precision and good recovery of compounds of interest. ASE showed good extraction efficiency in less time as compared to other techniques for all the phenolic compounds. The present method would be useful for analytical research and for routine analysis of vanilla extracts for their quality control. [source] TEXTURE OF SEMI-SOLIDS: SENSORY FLAVOR-TEXTURE INTERACTIONS FOR CUSTARD DESSERTSJOURNAL OF TEXTURE STUDIES, Issue 2 2003RENÉ A. DE WIJK ABSTRACT Possible interactions between flavor and oral texture sensations were investigated for four flavorants, diacetyl, benzaldehyde, vanillin, and caffeine, added in two concentrations to model vanilla custard desserts. The flavorants affected viscosities and resulted in corresponding changes in perceived thickness and melting sensations. In addition, flavorants affected prickling sensations, probably via activation of the trigeminal nerve system, and sensations of roughness, astringency, and dryness/mealiness. Finally, the effects of flavorants on these individual texture attributes also resulted in flavorant effects on creaminess and fattiness, sensations based on combinations of the above attributes. [source] Utilisation of corn (Zea mays) bran and corn fiber in the production of food components,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2010Devin J Rose Abstract The milling of corn for the production of food constituents results in a number of low-value co-products. Two of the major co-products produced by this operation are corn bran and corn fiber, which currently have low commercial value. This review focuses on current and prospective research surrounding the utilization of corn fiber and corn bran in the production of potentially higher-value food components. Corn bran and corn fiber contain potentially useful components that may be harvested through physical, chemical or enzymatic means for the production of food ingredients or additives, including corn fiber oil, corn fiber gum, cellulosic fiber gels, xylo-oligosaccharides and ferulic acid. Components of corn bran and corn fiber may also be converted to food chemicals such as vanillin and xylitol. Commercialization of processes for the isolation or production of food products from corn bran or corn fiber has been met with numerous technical challenges, therefore further research that improves the production of these components from corn bran or corn fiber is needed. Published 2010 by John Wiley & Sons, Ltd. [source] Modifications of mechanical characteristics and phenolic composition in berry skins and seeds of Mondeuse winegrapes throughout the on-vine drying process,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2009Luca Rolle Abstract BACKGROUND: Among several common drying systems used in the enological sector the dry-on-vine (DOV) method assumes particular importance because famous wines such as Sauternes, Tokay and Ice Wines are produced by grapes dried using this system. Knowledge about trends in mechanical properties and phenolic composition during on-vine grape drying is scarce. The objective of this current study is therefore to increase the knowledge on these aspects. RESULTS: Berry skin break energy (+0.10 N) and berry skin thickness (+69 µm) values increase during grape dehydration, while the peduncle detach force decreases (,0.86 N). Large reductions in the anthocyanin content have also been observed (,40%), but their profile does not show significant changes. Seed hardness (,7.10 N, ,1.40 mJ) decreases during the withering, and higher seed springiness has been observed. Seed proanthocyanidins (+2050 mg kg berry,1) and flavanols vanillin assay (+670 mg kg berry,1) increase progressively throughout the withering. In contrast, a distinct lowering of these substances in the skins was noted. CONCLUSION: Many modifications in the chemical,physical characteristics of berries of Mondeuse winegrapes throughout the DOV process were found. The mechanical characteristics of grapes, in particular the peduncle detachment force, are important parameters in assessing their suitability for the drying-on-plant process. Copyright © 2009 Society of Chemical Industry [source] A kinetic study of the reactions of (+)-catechin with aldehydes derived from toasted oakJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2007Marie-Françoise Nonier Abstract The reactions between (+)-catechin and representative oak wood furanic (furfuraldehyde, 5-hydroxymethylfurfuraldehyde and 5-methylfurfuraldehyde) and phenolic (vanillin and syringaldehyde) aldehydes in a wine-like model solution were studied and the corresponding condensation kinetics at pH 3.0 and 3.5 were compared. A comparative study on the reactivity of these two representative families of aldehydes towards (+)-catechin showed a large difference between them. When incubated separately with (+)-catechin at both pH values, the reactions were faster with furanic aldehydes than with phenolic aldehydes. In mixtures containing (+)-catechin and individual aldehydes, new compounds were identified by high-performance liquid chromatography (HPLC)/UV,visible detection, some of which were characterised by liquid chromatography/electrospray ionisation mass spectrometry (LC/ESI-MS). The increase in solution absorbance with time was closely linked to these new products. Copyright © 2007 Society of Chemical Industry [source] Ferulic acid: pharmaceutical functions, preparation and applications in foodsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2004Shiyi Ou Abstract Ferulic acid (4-hydroxy-3-methoxycinnamic acid), an effective component of Chinese medicine herbs such as Angelica sinensis, Cimicifuga heracleifolia and Lignsticum chuangxiong, is a ubiquitous phenolic acid in the plant kingdom. It is mainly conjugated with mono- and oligosaccharides, polyamines, lipids and polysaccharides and seldom occurs in a free state in plants. Ferulic acid is a phenolic acid of low toxicity; it can be absorbed and easily metabolized in the human body. Ferulic acid has been reported to have many physiological functions, including antioxidant, antimicrobial, anti-inflammatory, anti-thrombosis, and anti-cancer activities. It also protects against coronary disease, lowers cholesterol and increases sperm viability. Because of these properties and its low toxicity, ferulic acid is now widely used in the food and cosmetic industries. It is used as the raw material for the production of vanillin and preservatives, as a cross-linking agent for the preparation of food gels and edible films, and as an ingredient in sports foods and skin protection agents. Ferulic acid can be prepared by chemical synthesis and through biological transformation. As polysaccharide ferulate is a natural and abundant source of ferulic acid, preparation of ferulic acid from plant cell wall materials will be a prospective pathway. Copyright © 2004 Society of Chemical Industry [source] Comparison between analytical methods and biological assays for the assessment of tannin-related antinutritive effects in some Spanish browse speciesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2004Hajer Ammar Abstract Twenty-two samples of leaves and flowers of six Mediterranean browse species (Erica australis, Quercus pyrenaica, Cistus laurifolius, Cytisus scoparius, Genista florida and Rosa canina) were analysed for total extractable phenols (TP), extractable tannins (ET) and condensed tannins (CTb (butanol/HCl assay) and CTv (vanillin assay)). The biological activity of the phenolic compounds was assessed as the increases in in vitro dry matter digestibility and gas production after in vitro incubation in rumen fluid following the addition of polyethylene glycol 6000 (PEG). The concentrations of phenolics and tannins varied with species, sampling time and part of the plant (leaves or flowers). There were also large differences in the values determined by different analytical methods. The highest correlation coefficients (P < 0.001) were found between TP and ET (r = 0.973) and between CTb and CTv (r = 0.758). However, only low correlations were observed between TP and CTb or CTv. Positive and significant (P < 0.01) correlations were observed between tannins and their biological activity determined as the effect of PEG on gas production. It is concluded that, although further research is required to develop methods for the accurate quantification of biologically active tannins, the effect of PEG on in vitro gas production seems to have promising potential for the assessment of phenolic-related antinutritive effects in browse plants. This technique, coupled with other tannin assays, could provide a better understanding of the nutritional and physiological significance of tannins. Copyright © 2004 Society of Chemical Industry [source] Effects of processing and storage on walnut (Juglans regia L) tannins,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2001Kar Wai Clara Sze-Tao Abstract Walnut tannins were maximally extracted with absolute methanol and an extraction time of 60,min. Storage (21 days at 25,°C) significantly reduced (20,40% reduction) the assayable tannin content in walnuts. The ranges of tannin content in freshly cracked inshell and shelled walnuts were respectively 372,1095 and 363,667,mg catechin equivalent per 100,g dry weight. The assayable tannin content in inshell and shelled walnuts was 10,20% higher when the particle size was reduced from 2- to 8-mesh. Using 0.5 as compared to 2% (w/v) vanillin as colour development reagent yielded 15,20% higher assayable tannin contents. The assay colour development reached a maximum after 20,min of incubation at 25,°C. Roasting (204,°C for 5,min) caused a small (14%) but significant reduction in assayable tannins. Soaking in aqueous alkali solutions was more effective (44,100% reduction) than soaking in aqueous acid solutions (6,76% reduction) in decreasing the assayable tannin content in walnuts. Microwave heating in distilled deionised water resulted in 93,98% reduction in walnut assayable tannins. Blanching at 100,°C for 2,min was as effective as alkali soaking in significantly reducing the amount of extractable walnut tannins (98% reduction). The tannin content in blanched walnuts was positively related to astringency scores (r,,=,0.92). © 2001 Society of Chemical Industry [source] Quantitative determination of phyllanthin and hypophyllanthin in Phyllanthus species by high-performance thin layer chromatographyPHYTOCHEMICAL ANALYSIS, Issue 6 2006Arvind K. Tripathi Abstract A simple, precise and rapid high-performance thin-layer chromatographic method has been developed for the estimation of phyllanthin (1) and hypophyllanthin (2), the important lignans of Phyllanthus species, especially Phyllanthus amarus. Separation of 1 and 2 was carried out on silica gel 60 F254 layers eluted with hexane:acetone:ethyl acetate (74:12:8), and the analytes were visualised through colour development with vanillin in concentrated sulphuric acid and ethanol. Scanning and quantification of spots was performed at 580 nm. Recoveries of 1 and 2 were 98.7 and 97.3%, respectively. The method was validated and the peak purities and limits of detection and quantification were determined. Copyright © 2006 John Wiley & Sons, Ltd. [source] Quantitative determination of oleane derivatives in Terminalia arjuna by high performance thin layer chromatographyPHYTOCHEMICAL ANALYSIS, Issue 4 2002D. V. Singh Abstract A simple, precise and rapid high performance thin layer chromatographic method has been developed for the simultaneous quantitative determination of five oleane derivatives, namely, arjunic acid, arjunolic acid, arjungenin, arjunetin and arjunglucoside I from stem bark extract of Terminalia arjuna. The isolation and separation of these compounds was carried out on 60F254 layers eluted with chloroform:methanol (90:10), and the analytes were visualised through colour development with vanillin in concentrated sulphuric acid:ethanol. Scanning and quantification of the spots at 640,nm showed good recoveries in the range 96.40,101.7%. Copyright © 2002 John Wiley & Sons, Ltd. [source] Schiff base substitute polyphenol and its metal complexes derived from o -vanillin with 2,3-diaminopyridine: synthesis, characterization, thermal, and conductivity propertiesPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 9 2008smet Kaya Abstract Poly-2,3 - bis[(2-hydroxy-3-methoxyphenyl)methylene]diamino pyridine (PHMPMDAP) that a new Schiff base polymer has been synthesized and characterized by spectroscopy, elemental, and thermal analyses techniques. This azomethine polymer was found to form complexes readily with Cu(II), Zn(II), Co(II), Pb(II), and Fe(II). From IR and UV-Vis studies, the phenolic oxygen and imine nitrogen of the ligand were found to be the coordination sites. Thermogravimetric analysis (TGA) data indicate the polymer to be more stable than the monomer. The structure of the polymer obtained was confirmed by FT-IR, UV-Vis, 13C-NMR, and 1H-NMR. Characterization was undertaken by TGA, size exclusion chromatography (SEC), and solubility tests. Also, electrical conductivities of PHMPMDAP and polymer,metal complexes are measured by four probe technique. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||