Vanillic Acid (vanillic + acid)

Distribution by Scientific Domains
Distribution within Chemistry


Selected Abstracts


Comparative study of 11 phenolic acids and five flavan-3-ols in cv. Vidal: impact of natural icewine making versus concentration technology

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2009
R.R. TIAN
Abstract Background and Aims:, In an effort to protect the development of the icewine production industry, this study aimed to find indicators to distinguish between authentic and non-authentic icewines. Methods and Results:, Fully ripened berries were used to prepare three types of high-sugar grape juices: naturally frozen juice, refrigerator-frozen juice and concentrated juice. The content of phenolic acids and flavan-3-ols in the samples before and after fermentation was assayed. Significant differences were found in the individual level of most phenolic acids and flavan-3-ols except chlorogenic acid, sinapic acid and (,)-epicatechin among the three types of high-sugar juices. At the end of fermentation, there were significant differences in the wines, not attributable to the influence of yeasts. Conclusions:, Vanillic acid, caffeic acid, (,)-epigallocatechin gallate, gentisic acid and syringic acid may be used as indicators of authentic icewine. Significance of the Study:, This work provides a basis for distinguishing authentic icewine and controlling icewine quality. [source]


Bacterioplankton assemblages transforming dissolved organic compounds in coastal seawater

ENVIRONMENTAL MICROBIOLOGY, Issue 8 2007
Xiaozhen Mou
Summary To characterize bacterioplankton functional assemblages that transform specific components of the coastal seawater dissolved organic carbon (DOC) pool, bromodeoxyuridine (BrdU) was used to label the bacterioplankton cells that were active following addition of single-DOC model compounds: two organic osmolytes [dimethylsulfoniopropionate (DMSP) and glycine betaine (GlyB)] and two aromatic monomers [para -hydroxybenzoic acid (pHBA) and vanillic acid (VanA)]. Bacterial populations were analysed based on in situ fluorescent immunodetection of BrdU incorporation followed by fluorescence-activated cell sorting (FACS). Sorted cells were then characterized by 16S rDNA-based analysis. Populations with high BrdU incorporation level (HI) developed within 8 h of introduction of 100 nM model compound. Terminal restriction fragment length polymorphisms (T-RFLP) analysis indicated that the HI populations in all four amendments were composed of bacteria from the same major taxa (phylum and subphylum levels), but the relative abundance of each differed. High-resolution clone libraries (each containing ,200 clones) showed that the HI populations in the GlyB and VanA amendments consisted of both metabolic generalists and specialists within the , -Proteobacteria (mainly members of the Roseobacter clade), , -Proteobacteria and , -Proteobacteria (mainly members of Altermonadaceae, Chromatiaceae, Oceanospirillaceae and Pseudomonadaceae). The presence of members of OM60/241, OM185, SAR11, SAR86 and SAR116 in the HI populations indicated that members of these groups can assimilate the model DOC compounds, providing some of the first glimpses into heterotrophy by members of these poorly understood environmental clusters. [source]


Phenolic compounds and some quality parameters of pumpkin seed oil

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2010
Mirjana 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]


The Aerobic Oxidative Cleavage of Lignin to Produce Hydroxyaromatic Benzaldehydes and Carboxylic Acids via Metal/Bromide Catalysts in Acetic Acid/Water Mixtures

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2009
Walt 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]


Formation and reactions of cluster ions from aromatic carboxylic acids together with amino acids

ISRAEL JOURNAL OF CHEMISTRY, Issue 2 2001
Anja Meffert
The cluster formation of several aromatic carboxylic acids, ferulic acid, vanillic acid, sinapinic acid, and 3,4-dihydroxybenzoic acid was investigated by means of laser desorption into a supersonic beam followed by multiphoton ionization-time-of-flight mass spectrometry. The formation of not only homogeneous clusters, but also of heterogeneous clusters with some small amino acids was studied. The different neutral clusters formed in the supersonic expansion were ionized by a multiphoton process employing either nano- or femtosecond laser pulses. Strong differences in the detection of cluster ions due to the laser pulse length employed for multiphoton ionization were observed. Only femtosecond activation led to mass spectra with intense signals of the cluster ions. In addition, in the case of femtosecond ionization, protonated amino acids were detected in the mass spectra. As direct ionization of the free amino acids is not possible under the chosen ionization conditions because they lack an adequate chromophore, these protonated amino acids are assumed to be formed via an intracluster proton transfer in the heterogeneous dimer and subsequent decay of the ionized cluster (dissociative proton transfer). Such well-known processes for heterogeneous clusters consisting of a substituted aromatic molecule and small polar solvent molecules may be involved in the matrixassisted laser desorption ionization (MALDI) process. [source]


Inhibitory effects of urinary metabolites on platelet aggregation after orally administering Shimotsu-To, a traditional Chinese medicine, to rats

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2003
Takaaki Yasuda
ABSTRACT Shimotsu-To, which consists of four herbal extracts, has been used clinically for improving abnormal blood coagulation, fibrinolysis, atherosclerosis and chronic inflammation in Japan and China. We have investigated the pharmacological relationship between the effects and chemical components of Shimotsu-To after oral administration to rats. The urinary constituents were separated and identified by three dimensional (3D-) HPLC equipped with a photodiode array detector as a new tool and the chemical structures were determined by spectroscopic methods to be trans -ferulic acid-3- O -sulfate (1), vanillic acid (2), m -hydroxyphenylpropionic acid (3), trans -ferulic acid (4) and cis -ferulic acid (5). Of these compounds, 2,5 strongly inhibited platelet aggregation induced by ADP and arachidonic acid. Compound 1, the sulfate conjugate of 4, did not show any inhibitory effect, which suggested that the inhibitory effect on platelet aggregation was inactivated by sulfate conjugation. These results indicated that compounds 2,5 partly contributed to the anti-Oketsu effect of Shimotsu-To through the inhibition of platelet aggregation. [source]


Coumarins and phenolic fingerprints of oak and Brazilian woods extracted by sugarcane spirit

JOURNAL OF SEPARATION SCIENCE, JSS, Issue 21 2009
Alexandre 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]


Determination of the main bioactive metabolites of Radix Salvia miltiorrhizae in Compound Danshen Dripping Pills and the tissue distribution of Danshensu in rabbit by SPE-HPLC-MSn

JOURNAL OF SEPARATION SCIENCE, JSS, Issue 6 2007
Zheng Xiaohui
Abstract A fast solid phase extraction-high performance liquid chromatography-ion trap mass spectrometry (SPE-HPLC-MSn) method is presented for quantitative determination of 3-(3,4-dihydroxyphenyl)-2-hydroxylpropionic acid (Danshensu, DSS) from Compound Danshen Dripping Pills (CDDP) in rabbits' heart, liver, kidney, and lung and for qualitative analysis of the bioactive metabolites of Radix Salvia miltiorrhizae (DS) from CDDP in these tissues. The proposed method was validated with a detection limit of 0.06 ng/mL and a linear range of 5.0,200 ng/mL for DSS. The main metabolites of DS were pyrocatechol, vanillic acid, isopropyl 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate, and 2-hydroxyl-3-(3,4-dihydroxyphenyl)propinonic sulfuric anhydride. In vitro pharmacological experiments demonstrated that isopropyl 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate had a distinct vasodilatating action. [source]


Determination of some hydroxybenzoic acids and catechins in white wine samples by liquid chromatography with luminescence detection

JOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2006
Rafael Carlos Rodríguez-Díaz
Abstract A liquid chromatographic method with luminescence detection for the determination of eight phenolic compounds is reported. The method involves postcolumn derivatization with terbium(III). This derivatization is based on the reaction between phenolics and terbium(III) to form luminescent chelates, which were determined at ,ex 295 and ,em 545 nm using the fluorescence mode. The long wavelength emission of lanthanide chelates can minimize interferences from background sample matrix, which usually emit at shorter wavelengths. Also, the chromatographic separation allows the individual determination of phenolics, which cannot be done using the direct measurement of the fluorescence of their corresponding terbium chelates. Dynamic ranges of the calibration graphs and detection limits, obtained with standard solutions of analytes were (,g/mL): gallic acid (0.9,40, 0.3), protocatechuic acid (0.05,7, 0.016), catechin (0.2,40, 0.07), vanillic acid (0.25,40, 0.08), p -hydroxybenzoic acid (0.8,40, 0.25), syringic acid (0.17,40, 0.05), epicatechin (0.3,40, 0.09) and salicylic acid (0.07,12, 0.02). The precision was established at two concentration levels of each analyte and expressed as the percentage of RSD with values ranging between 1.0 and 6.5%. The practical usefulness of the method was demonstrated by the analysis of white wine samples, which were diluted two-fold and directly injected into the chromatographic system. The recovery values obtained ranged between 93.3 and 108.0%. [source]


Influence of branch bending on sugar, organic acid and phenolic content in fruits of ,Williams' pears (Pyrus communis L.)

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006
Mateja Colaric
Abstract Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ,Williams' pears using high-performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg,1 fresh weight (FW) of fructose, 9.42 g kg,1 FW of glucose, 7.94 g kg,1 FW of sucrose and 24.59 g kg,1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg,1 FW, 2.24 g kg,1 FW, 71.79 mg kg,1 FW and 0.49 mg kg,1 FW, respectively). Chlorogenic acid (280.86,357.34 mg kg,1 FW) was the predominant phenolic acid, followed in concentration (mg kg,1 FW) by syringic acid (95.46,131.32), epicatechin (46.55,83.09), catechin (25.67,44.81), vanillic acid (1.87,3.48), sinapic acid (0.83,1.72) and caffeic acid (0.72,1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry [source]


Use of a lactic acid bacteria starter culture during green olive (Olea europaea L cv Ascolana tenera) processing

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2005
Vincenzo Marsilio
Abstract Among the Italian olive germplasm, ,Ascolana tenera' is one of the best varieties for table olive production. This research addressed the impact of different processing types (Greek-style and Spanish-style) on the fermentation and phenolic composition of olive fruit. In particular, the effects of a lactic acid bacteria (LAB) starter culture on the fermentation of naturally green olives processed according to the traditional Greek method were studied. Results revealed that Spanish-style processing produced a dramatic loss of total phenolics, while natural olive processing favoured a higher retention of biophenols. Oleoside 11-methylester, a phenol-related compound, and hydroxytyrosol, tyrosol, vanillic acid, 3,4-dihydroxyphenylglycol, oleuropein and oleuropein aglycons, as the main phenols, were detected in olive fruit. More interestingly, this research indicated that inoculation with LAB affected the pH, total acidity, microbial profile and palatability of olives. Olives fermented with the LAB starter culture were perceived by panellists to be less bitter and more aromatic than those spontaneously fermented. Thus the use of LAB inoculants during olive fermentation could be applied with the currently available technology. Copyright © 2005 Society of Chemical Industry [source]


Total antioxidant capacity and content of flavonoids and other phenolic compounds in canihua (Chenopodium pallidicaule): An Andean pseudocereal

MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 6 2008
J. Mauricio Peńarrieta
Abstract Total antioxidant capacity (TAC), total phenolic compounds (TPH), total flavonoids (TF) and individual phenolic compounds were determined in canihua collected at approx. 3850 m altitude. The TAC values varied among samples from 2.7 to 44.7 by the ferric reducing antioxidant power (FRAP) method and from 1.8 to 41 by the 2,2,-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method expressed as ,mol of Trolox equivalents/g dw. The content of TPH was 12.4,71.2 ,mol gallic acid equivalents/g dw and that of the TF ranged between 2.2 and 11.4 ,mol of catechin equivalents/g dw. The data obtained by the four methods showed several significant correlations. Prior to analysis by HPLC, the samples were subjected to acid hydrolysis and in the water-soluble extracts this led to an up to 20-fold increase in the TAC values in comparison with the values of the nonhydrolysed samples. HPLC analysis showed the presence of eight major compounds identified as catechin gallate, catechin, vanillic acid, kaempferol, ferulic acid, quercetin, resorcinol and 4-methylresorcinol. Their estimated contribution to the TAC value (FRAP method) indicated that resorcinols contributed most of the antioxidant capacity of the water-soluble extract. The results show that canihua is a potential source of natural antioxidant compounds and other bioactive compounds which can be important for human health. [source]


Fungitoxic phenols from carnation (Dianthus caryophyllus) effective against Fusarium oxysporum f. sp. dianthi

PHYTOCHEMICAL ANALYSIS, Issue 1 2003
Paolo Curir
Abstract The phenol compositions of two cultivars of carnation (Dianthus caryophyllus) namely "Gloriana" and "Roland", which are partially and highly resistant, respectively, to Fusarium oxysporum f. sp. dianthi have been investigated with the aim of determining if endogenous phenols could have an anti-fungal effect against the pathogen. Analyses were performed on healthy and F. oxysporum -inoculated in vitro tissues, and on in vivo plants. Two benzoic acid derivatives, protocatechuic acid (3,4-dihydroxybenzoic acid) and vanillic acid (4-hydroxy-3-methoxybenzoic acid), were found within healthy and inoculated tissues of both cultivars, together with the flavonol glycoside peltatoside (3-[6-O-(,- L -arabinopyranosyl)-,- D -glucopyranosyl] quercetin). These molecules proved to be only slightly inhibitory towards the pathogen. 2,6-Dimethoxybenzoic acid was detected in small amounts only in the inoculated cultivar "Gloriana", while the highly resistant cultivar "Roland" showed the presence of the flavone datiscetin (3,5,7,2,-tetrahydroxyflavone). The latter compound exhibited an appreciable fungitoxic activity towards F. oxysporum f. sp. dianthi. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Simultaneous analysis of catechol- O -methyl transferase activity, S -adenosylhomocysteine and adenosine

BIOMEDICAL CHROMATOGRAPHY, Issue 3 2010
Ilkka Reenilä
Abstract Novel HPLC method utilizing UV-detection was developed to analyse catechol- O -methyltransferase (COMT) products, vanillic acid and isovanillic acid, S -adenosylhomocysteine (SAH) and adenosine formed from dihydroxybenzoic acid and S -adenosyl-L-methionine (SAM) by incubation of the rat tissues. Entacapone, a COMT inhibitor, prevented the formation of SAH only partially in the striatal homogenate whereas in the kidney homogenate the increase of SAH was prevented by entacapone. In conclusion, this method was reliable, rapid and simple. COMT seemed to be partially responsible on the SAM utilizing methylations in the striatal homogenates while in the high COMT activity tissue, COMT was the main SAH producing methyltransferase. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Purification of bioethanol effluent in an UASB reactor system with simultaneous biogas formation

BIOTECHNOLOGY & BIOENGINEERING, Issue 1 2003
M. Torry-Smith
In this study, the prospect of using an Upflow Anaerobic Sludge Blanket (UASB) reactor for detoxification of process water derived from bioethanol production has been investigated. The bioethanol effluent (BEE) originated from wet oxidized wheat straw fermented by Saccharomyces cerevisiae and Thermoanaerobacter mathranii A3M4 to produce ethanol from glucose and xylose, respectively. In batch experiments the methane potential of BEE was determined to 529 mL-CH4/g-VS. In batch degradation experiments it was shown that the presence of BEE had a positive influence on the removal of the inhibitors 2-furoic acid, 4-hydroxyacetophenone, and acetovanillone as compared to conversion of the inhibitors as sole substrate in synthetic media. Furthermore, experiments were carried out treating BEE in a laboratory-scale UASB reactor. The results showed a Chemical Oxygen Demand (COD) removal of 80% (w/w) at an organic loading rate of 29 g-COD/(L · d). GC analysis of the lignocellulosic related potentially inhibitory compounds 2-furoic acid, vanillic acid, homovanillic acid, acetovanillone, syringic acid, acetosyringone, syringol, 4-hydroxybenzoic acid, and 4-hydroxybenzaldehyde showed that all of these compounds were removed from the BEE in the reactor. Implementation of a UASB purification step was found to be a promising approach to detoxify process water from bioethanol production allowing for recirculation of the process water and reduced production costs. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 7,12, 2003. [source]


Determination of Bioactive Components in Polygonum perfoliatum L. by Capillary Electrophoresis with Electrochemical Detection

CHINESE JOURNAL OF CHEMISTRY, Issue 4 2009
Shuping JIN
Abstract The major bioactive components in a Chinese herb named Polygonum perfoliatum L. including ferulic acid, vanillic acid, quercetin, caffeic acid and protocatechuic acid were simultaneously determined by capillary electrophoresis with electrochemical detection (CE-ED) in this paper. The effects of working electrode potential, pH and concentration of running buffer, separation voltage, and injection time on CE-ED were investigated. Under the optimum conditions, the five analytes could be separated within 17 min at a separation voltage of 18 kV in 10 mmol· L,1 phosphate buffer (pH 9.2). A 300 µm diameter carbon disk electrode generated good responses at +0.95 V (vs. SCE) to the five analytes. The response was linear over three orders of magnitude with detection limits (S/N=3) ranging from 7.1×10,8 to 9.3×10,8 g·mL,1 for the analytes. This proposed method could be successfully applied to the analysis of the real samples with relatively simple extraction procedures and satisfactory results. [source]


Storage and Cultivar Effects on Shear Compression Values and Esterified Cell Wall Phenolics in Carrots

JOURNAL OF FOOD SCIENCE, Issue 9 2001
T. 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]


Inhibition of browning by antibrowning agents and phenolic acids or cinnamic acid in the glucose,lysine model

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2005
Eun-Jung Kwak
Abstract The effects of antibrowning agents and phenolic acids or cinnamic acid on the inhibition of browning were investigated with a glucose,lysine model. Six antibrowning agents (cysteine, glutathione, sodium sulfite, pentasodium tripolyphosphate, citric acid and oxalic acid) and four phenolic acids (ferulic, hydroxybenzoic, syringic and vanillic acids) were used. In order to investigate the antibrowning capacity of these agents, model solutions containing glucose, lysine and an antibrowning agent were heated at 50 °C in the presence of FeCl2, before being stored in nitrogen or air at 4 °C or 30 °C. Browning was accelerated to some degree during storage in air at 30 °C. In the case of storage at 4 °C, however, no browning was detected in nitrogen after four weeks. Citric acid was the most efficient antibrowning agent during storage in air at 30 °C and inhibited browning to 36% after four weeks. However, its antibrowning capacity was increased by 8,15% in the presence of any of the phenolic acids or cinnamic acid, essentially independently of concentration in the range 10 µM to 10 mM or the type of phenolic acid. Copyright © 2005 Society of Chemical Industry [source]