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Validation of an Analytical Method for Nitrite and Nitrate Determination in Meat Foods for Infants by Ion Chromatography with Conductivity Detection. Foods 2020; 9:foods9091238. [PMID: 32899742 PMCID: PMC7555295 DOI: 10.3390/foods9091238] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 11/30/2022] Open
Abstract
Nitrate and nitrite as sodium or potassium salts are usually added to meat products to develop the characteristic flavor, to inhibit the growth of microorganisms (particularly Clostridium botulinum), and effectively control rancidity by inhibiting lipid oxidation. However, both nitrate and nitrite ions need to be monitored for ensuring the quality and safety of cured meats. In this work, for the first time the content of nitrite and nitrate ions in homogenized meat samples of baby foods was determined by a validated method based on ion chromatography (IC) coupled with conductivity detection. Recoveries of nitrate and nitrite ions in meat samples were not lower than 84 ± 6%. The detection limits of nitrate and nitrite were 0.08 mg L−1 and 0.13 mg L−1, respectively. Five commercial samples of homogenized meat, namely lamb, rabbit, chicken, veal, and beef, for infant feeding were investigated; while nitrite content was below the detection limit, nitrate ranged from 10.7 to 21.0 mg kg−1. The results indicated that nitrate contents were below the European (EU) fixed value of 200 mg kg−1, and an acceptable daily intake of 3.7 mg kg−1 was estimated.
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2
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Oellig C, Link K, Schwack W. Characterization of E 472 food emulsifiers – determination of bound and free fruit acids, free glycerol and ash content. J Chromatogr A 2020; 1619:460946. [DOI: 10.1016/j.chroma.2020.460946] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 02/01/2020] [Accepted: 02/03/2020] [Indexed: 11/28/2022]
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3
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Sonsa-Ard T, Nacapricha D, Kaneta T. Miniaturized Potentiometric Titration for Improving Portability and Accuracy in the Determination of Total Acid in Squeezed Fruit Juice. J Food Sci 2019; 84:2165-2170. [PMID: 31313309 DOI: 10.1111/1750-3841.14721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/27/2019] [Accepted: 06/06/2019] [Indexed: 11/29/2022]
Abstract
To determine the total acidity in freshly squeezed fruit juice, we miniaturized the potentiometric titrations and achieved better accuracy compared with titrations from a conventional pH probe. The improvement was the result of a higher jump in pH at the endpoint due to a reduction in the dilutions of both the titrand and titrant. A conventional pH probe requires more than 50 mL of titrand, which can lead to a 25000-fold dilution of the titrant when adding the titrant at 2 µL intervals. Conversely, when the volume of the titrand can be reduced to 1 mL, the dilution is only 500-fold, which results in a higher jump in pH at the endpoint. The concentration of the titrant, NaOH, was optimized by titrating sample solutions containing 25 and 50 mM of citric acid. The addition of 5 M NaOH in intervals of 2 µL led to a more accurate endpoint for both 25 and 50 mM citric acid solutions. Miniaturization of the titration process is advantageous in terms of portability, accuracy, and in requiring less consumption of a sample, thereby simplifying the process of repeat measurements that are helpful in evaluating the precision of analytical results. Practical samples of squeezed fruit juices were titrated via three methods that showed no significant differences: classic titrimetry with an indicator, conventional potentiometry, and miniaturized potentiometry. This process would be effective for use in the field and in developing countries. PRACTICAL APPLICATION: The total acidity of fruits and fruit juices is an important indicator of quality and is generally expressed in terms of the citric acid content. However, a standard potentiometric titration requires a large sample volume, which makes it difficult to assess dispersion of the acidity for individual fruits. The results of this study indicate that the use of miniaturized potentiometric titration could benefit food chemistry in many developing countries in addition to opening new fields of food chemistry such as on-site quality control of citrus fruit and evaluation of variations in quality.
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Affiliation(s)
- Thitaporn Sonsa-Ard
- Flow Innovation-Research for Science and Technology Laboratories (Firstlabs), and the Dept. of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol Univ., Bangkok, 10400, Thailand
| | - Duangjai Nacapricha
- Flow Innovation-Research for Science and Technology Laboratories (Firstlabs), and the Dept. of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol Univ., Bangkok, 10400, Thailand
| | - Takashi Kaneta
- Dept. of Chemistry, Graduate School of Natural Science and Technology, Okayama Univ., Okayama, 700-8530, Japan
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4
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Anvarian AHP, Smith MP, Overton TW. Use of flow cytometry and total viable count to determine the effects of orange juice composition on the physiology of Escherichia coli. Food Sci Nutr 2018; 6:1817-1825. [PMID: 30349671 PMCID: PMC6189610 DOI: 10.1002/fsn3.756] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/05/2018] [Accepted: 07/10/2018] [Indexed: 12/21/2022] Open
Abstract
Orange juice (OJ) contains numerous compounds some of which are known to play key roles in growth and survival of bacteria. This study aimed to investigate the effects of natural or processing-induced variations in OJ composition on the physiology of Escherichia coli. OJ and model OJ (MOJ) samples containing various sugars, organic acids, amino acids, or ascorbic acid were inoculated with E. coli K-12 MG1655 in different growth phases. The culturability, viability, and physiology of the cells were investigated during storage using plate counting and flow cytometry. Generally, stationary-phase cells displayed the greatest survival in both MOJ and OJ. Increase in incubation temperature from 4 to 22.5ºC caused a significant decrease in both healthy and culturable cell populations. Supplementation of MOJ with ascorbic acid and amino acids increased both the viability and culturability of the cells. Similar trends were observed in amino acid-supplemented OJ, albeit at a slower rate. In contrast, variations in sugar or organic acid composition had negligible effects on the physiological status of the cells. In summary, natural variation in ascorbic acid or amino acid concentrations could potentially have an adverse effect on the microbiological safety of orange juice.
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Affiliation(s)
- Amir H. P. Anvarian
- BioengineeringSchool of Chemical EngineeringThe University of BirminghamBirminghamUK
- Present address:
National Centre for Food ManufacturingHolbeach Technology ParkUniversity of LincolnHolbeachLincolnshireUK
| | - Madeleine P. Smith
- BioengineeringSchool of Chemical EngineeringThe University of BirminghamBirminghamUK
| | - Tim W. Overton
- BioengineeringSchool of Chemical EngineeringThe University of BirminghamBirminghamUK
- Institute of Microbiology & InfectionThe University of BirminghamBirminghamUK
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5
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Quantification of inorganic anions and organic acids in apple and orange juices using novel covalently-bonded hyperbranched anion exchanger with improved selectivity. J Chromatogr A 2018; 1567:130-135. [DOI: 10.1016/j.chroma.2018.06.065] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/18/2018] [Accepted: 06/26/2018] [Indexed: 11/21/2022]
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6
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Dobson G, McDougall GJ, Stewart D, Cubero MÁ, Karjalainen RO. Effects of Juice Matrix and Pasteurization on Stability of Black Currant Anthocyanins during Storage. J Food Sci 2016; 82:44-52. [DOI: 10.1111/1750-3841.13575] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/22/2016] [Accepted: 11/09/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Gary Dobson
- Environmental and Biochemical Sciences Group; The James Hutton Inst; Invergowrie Dundee DD2 5DA United Kingdom
| | - Gordon J. McDougall
- Environmental and Biochemical Sciences Group; The James Hutton Inst; Invergowrie Dundee DD2 5DA United Kingdom
| | - Derek Stewart
- Environmental and Biochemical Sciences Group; The James Hutton Inst; Invergowrie Dundee DD2 5DA United Kingdom
- NIBIO; Norwegian Inst. of Bioeconomy Research; Pb115, NO-1431 Ås Norway
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7
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Single-Run Separation and Determination of Aliphatic and Aromatic Carboxylic Acids in Wine and Human Urine Samples by Ion-Exclusion Chromatography. Chromatographia 2014. [DOI: 10.1007/s10337-014-2706-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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8
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Nawirska-Olszańska A, Biesiada A, Sokół-Łętowska A, Kucharska AZ. Characteristics of organic acids in the fruit of different pumpkin species. Food Chem 2014; 148:415-9. [DOI: 10.1016/j.foodchem.2013.10.080] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 10/14/2013] [Accepted: 10/17/2013] [Indexed: 11/25/2022]
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9
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Guyon F, Gaillard L, Brault A, Gaultier N, Salagoïty MH, Médina B. Potential of ion chromatography coupled to isotope ratio mass spectrometry via a liquid interface for beverages authentication. J Chromatogr A 2013; 1322:62-8. [PMID: 24267317 DOI: 10.1016/j.chroma.2013.10.088] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 10/28/2013] [Accepted: 10/29/2013] [Indexed: 11/25/2022]
Abstract
New tools for the determination of characteristic parameters for food authentication are requested to prevent food adulteration from which health concerns, unfair competition could follow. A new coupling in the area of compound-specific carbon 13 isotope ratio (δ(13)C) analysis was developed to simultaneously quantify δ(13)C values of sugars and organic acids. The coupling of ion chromatography (IC) together with isotope ratio mass spectrometry (IRMS) can be achieved using a liquid interface allowing a chemical oxidation (co) of organic matter. Synthetic solutions containing 1 polyol (glycerol), 3 carbohydrates (sucrose, glucose and fructose) and 12 organic acids (gluconic, lactic, malic, tartaric, oxalic, fumaric, citric and isocitric) were used to optimize chromatographic conditions (concentration gradient and 3 types of column) and the studied isotopic range (-32.28 to -10.65‰) corresponds to the values found in food products. Optimum chromatographic conditions are found using an IonPac AS15, an elution flow rate of 0.3mLmin(-1) and a linear concentration gradient from 2 to 76mM (rate 21mMmin(-1)). Comparison between δ(13)C value individually obtained for each compound with the coupling IRMS and elemental analyzer, EA-IRMS, and the ones measured on the mixture of compounds by IC-co-IRMS does not reveal any isotope fractionation. Thus, under these experimental conditions, IC-co-IRMS results are accurate and reproducible. This new coupling was tested on two food matrices, an orange juice and a sweet wine. Some optimization is necessary as the concentration range between sugars and organic acids is too large: an increase in the filament intensity of the IRMS is necessary to simultaneously detect the two compound families. These first attempts confirm the good results obtained on synthetic solutions and the strong potential of the coupling IC-co-IRMS in food authentication area.
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Affiliation(s)
- Francois Guyon
- Service Commun des Laboratoires, 3 Avenue du Dr A. Schweitzer, 33608 Pessac, France.
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10
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Liao H, Shelor CP, Chen Y, Sabaa-Srur AUO, Smith RE, Dasgupta PK. Anion composition of açaı́ extracts. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:5928-5935. [PMID: 23772604 DOI: 10.1021/jf4014185] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Many products labeled açaı́ are presently marketed as natural supplements with various claimed health benefits. Authentic açaı́ is expensive; as a result, numerous products labeled as containing açaı́ are being sold that actually contain little or no açaı́. Authentic açaı́ samples from Brazil and Florida as well as several reputed açaı́ products were analyzed by suppressed conductometric anion chromatography. Columns with different selectivities were used to obtain a complete separation of all anions. Tandem mass spectrometry was used for confirmation of the less common ions. Quinate, lactate, acetate, formate, galacturonate, chloride, sulfate, malate, oxalate, phosphate, citrate, isocitrate, and myo-inositol hexakisphosphate (phytate) were found. Only the Florida açaı́ had detectable levels of hexanoate. No açaı́ sample had any detectable levels of tartrate, which is present in abundance in grape juice, the most common adulterant. The highly characteristic anion profile and in particular the absence of tartrate can readily be used to identify authentic açaı́ products. Açaı́ from Florida had a 6 times greater level of phytate. The present analytical approach for phytate may be superior to extant methods.
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Affiliation(s)
- Hongzhu Liao
- Department of Chemistry and Biochemistry, University of Texas at Arlington , Arlington Texas 76019-0065, United States
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11
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Jaworska G, Sady M, Grega T, Bernaś E, Pogoń K. Qualitative comparison of blackcurrant and blackcurrant--whey beverages. FOOD SCI TECHNOL INT 2011; 17:331-41. [PMID: 21844063 DOI: 10.1177/1082013210382480] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study provides a qualitative comparison of blackcurrant and blackcurrant-whey beverages over a 12-month storage period. The amount of extract in the beverages was established as 12%, of which 25% was blackcurrant concentrate. Acid whey was used for the production of blackcurrant-whey beverages. In comparison to blackcurrant-whey beverages, blackcurrant beverages contained significantly more glucose, fructose, sucrose, polyphenols and vitamins C and B1. They also had a higher level of antioxidant activity against ABTS•+ and DPPH, with the difference ranging from 2% to 46%. On the other hand, blackcurrant-whey beverages contained more ash, proteins and vitamin B2 and the presence of lactose was detected. They were also characterized by higher color parameter values evaluated according to the CIE system. A general sensory evaluation awarded blackcurrant beverages with 0.5-1.3 more points than blackcurrant-whey beverages. A descriptive flavor analysis found that blackcurrant taste dominated in both types of beverages; however, in blackcurrant-whey beverages, the taste and smell of whey were also discernible. Changes in the quality of the beverages were observed during the storage period, notably a decrease in their antioxidant properties.
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Affiliation(s)
- G Jaworska
- Department of Raw Material and Processing of Fruit and Vegetables, Agricultural University of Krakow, 122 Balicka Street, 30-149 Krakow, Poland.
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12
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Németh S, Szalay L, Ficzek G, Stéger-Máté M, Sándor G, Végvári G, Tóth M. Analysis of chemical parameters determining the fruit quality of apricot cultivars during ripening. ACTA ALIMENTARIA 2011. [DOI: 10.1556/aalim.40.2011.suppl.11] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Determination of galacturonic acid content in pectin from fruit juices by liquid chromatographydiode array detection-electrospray ionization tandem mass spectrometry. OPEN CHEM 2010. [DOI: 10.2478/s11532-010-0101-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractA reversed-phase high-performance liquid chromatographic (HPLC) method is applied for the determination of galacturonic acid (GA) of pectins in different commercial fruit juices. The separation was carried out on a C18 column using precolumn derivatization with p-aminobenzoic acid (p-ABA) and UV detection at 304 nm. The identification of GA was confirmed by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) in positive ion mode. The concentration of GA in the samples analyzed ranged from 12.9 ± 0.5 to 49.4 ± 0.5 mgGA L−1. Amongst the samples analyzed, mango juice was found to be richest in GA content, and therefore a good source of pectins. Detection and quantification limits of the described methodology were 1.2 and 3.9 mg L−1, respectively. Quantitative GA recoveries in the beverages had a range between 90 and 98%. The results showed that the HPLC method proposed was precise and suitable for the identification and quantification of GA in commercial fruit juices.
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14
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Zheng YJ, Duan YT, Zhang YF, Pan QH, Li JM, Huang WD. Determination of Organic Acids in Red Wine and Must on Only One RP-LC-Column Directly After Sample Dilution and Filtration. Chromatographia 2009. [DOI: 10.1365/s10337-009-1085-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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15
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Determination of organic acids evolution during apple cider fermentation using an improved HPLC analysis method. Eur Food Res Technol 2008. [DOI: 10.1007/s00217-008-0835-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Cen H, Bao Y, He Y, Sun DW. Visible and near infrared spectroscopy for rapid detection of citric and tartaric acids in orange juice. J FOOD ENG 2007. [DOI: 10.1016/j.jfoodeng.2007.02.039] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Jakmunee J, Rujiralai T, Grudpan K. Sequential Injection Titration with Spectrophotometric Detection for the Assay of Acidity in Fruit Juices. ANAL SCI 2006; 22:157-60. [PMID: 16429794 DOI: 10.2116/analsci.22.157] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A simple sequential injection analysis (SIA) with spectrophotometric detection for an assay of acidity in fruit juice was investigated. An alkaline reagent (sodium hydroxide), a sample and an indicator (phenolphthalein) were first aspirated and stacked as adjacent zones in a holding coil. With flow reversal through a reaction coil to the detector, zone penetration occurred, leading to a neutralization reaction that caused a decrease in the color intensity of the indicator being monitored for absorbance at 552 nm. The effects of various parameters were studied. Linear calibration graphs for acidities of 0.2 - 1.0 and 0.5 - 2.5% w/v citric acid as a standard, with a relative standard deviation of 1% (acidity of 0.3 - 0.6% w/v as citric acid, n=11) and a sample throughput of 30 samples h(-1), were achieved. The developed method was validated by a standard titrimetric method for assaying the acidity of fruit juice samples.
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Affiliation(s)
- Jaroon Jakmunee
- Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
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18
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Mato I, Suárez-Luque S, Huidobro JF. A review of the analytical methods to determine organic acids in grape juices and wines. Food Res Int 2005. [DOI: 10.1016/j.foodres.2005.04.007] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Chinnici F, Spinabelli U, Riponi C, Amati A. Optimization of the determination of organic acids and sugars in fruit juices by ion-exclusion liquid chromatography. J Food Compost Anal 2005. [DOI: 10.1016/j.jfca.2004.01.005] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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Búriová E, Medová M, Macásek F, Brúder P. Separation and detection of oxidation products of fluorodeoxyglucose and glucose by high-performance liquid chromatography–electrospray ionisation mass spectrometry. J Chromatogr A 2004; 1034:133-7. [PMID: 15116922 DOI: 10.1016/j.chroma.2004.01.060] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
2-Deoxy-2-[18F]fluoro-D-glucose ([18F] FDG), the most popular positron emitting radiopharmaceutical, may oxidise by autoradiolysis in aqueous solution. The aim of this work was to use LC-MS for determination of the oxidation products of fluorodeoxyglucose and glucose (Glc) obtained by oxidation with Fenton's reagent. Asahipak NH2P-50 polyamide silica column and acetonitrile-0.025% aqueous ammonium formate (80:20 (v/v)) eluent were utilised with an Agilent 1100 HPLC-MS instrument. Ten major oxidation products of FDG and Glc were separated and identified by mass spectrometry: 2-fluorogluconic acid, 2-fluoroglucuronic acid, 2-oxoerythronic acid, arabinose, arabonic acid, araburonic acid, erythrose, erythrulose, gluconic acid, and glucuronic acid. The most intensive electrospray ionisation signals were found in the negative ion spectra and were due to HCOO- adducts, the other acids being in their lactone forms.
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Affiliation(s)
- E Búriová
- Department of Nuclear Chemistry, Faculty of Natural Sciences, Comenius University, Mlynska Dolina CH-1, SK-84215 Bratislava, Slovak Republic.
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Irudayaraj J, Tewari J. Simultaneous monitoring of organic acids and sugars in fresh and processed apple juice by Fourier transform infrared-attenuated total reflection spectroscopy. APPLIED SPECTROSCOPY 2003; 57:1599-604. [PMID: 14686782 DOI: 10.1366/000370203322640242] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A combination of Fourier transform infrared spectroscopy (FT-IR) and chemometrics was used as a screening tool for the determination of sugars and organic acids such as sucrose, glucose, fructose, sorbitol, citric acid, and malic acid in processed commercial and extracted fresh apple juices. Prepared samples of synthetic apple juice in different constituent concentration ranges were scanned by attenuated total reflectance (ATR) accessory and the spectral region in the range between 950 and 1500 cm(-1) was selected for calibration model development using partial least squares (PLS) regression and principal component regression (PCR). The calibration models were successfully validated by high-performance liquid chromatography (HPLC) measurements against several commercial juice varieties as well as juice extracted from different apple varieties to provide an overall R2 correlation of 0.998. The present study demonstrates that Fourier transform infrared spectroscopy could be used for rapid and nondestructive determination of multiple constituents in commercial and fresh apple juices. Results indicate this approach to be a rapid and cost-effective tool for routine monitoring of multiple constituents in a fruit juice production facility.
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Affiliation(s)
- Joseph Irudayaraj
- Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
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22
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Cawthray GR. An improved reversed-phase liquid chromatographic method for the analysis of low-molecular mass organic acids in plant root exudates. J Chromatogr A 2003; 1011:233-40. [PMID: 14518781 DOI: 10.1016/s0021-9673(03)01129-4] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Reversed-phase column liquid chromatography (RPLC) was used for the separation and quantification of 10 low-molecular-mass organic acids (malic, malonic, lactic, acetic, maleic, citric, cis-aconitic, succinic, fumaric, and trans-aconitic) in plant root exudates. A mobile phase of 93% 25 mM KH2PO4 at pH 2.5 and 7% methanol at a flow-rate of 1 ml min(-1) resolved all 10 acids in 15 min on a C18 column. Experiments demonstrated a significant (P < 0.05) effect of sample pH on detector response, with peak heights being significantly lower at pH 6.0 compared with pH 2.5, but peak area showed no significant difference. At pH 8.0 and above, both peak height and area differed significantly from injections made at pH 2.5. Limits of detection (LOD) for the 10 acids ranged from 0.05 to 24 microM. Finally, the improved method was applied for the analysis of root exudates from soil cultured field pea, Banksia attenuata, white lupin, and chickpea.
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Affiliation(s)
- Gregory R Cawthray
- School of Plant Biology (M090), Faculty of Natural and Agricultural Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
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23
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Saavedra L, Rupérez FJ, Barbas C. Capillary electrophoresis for evaluating orange juice authenticity: a study on Spanish oranges. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:9-13. [PMID: 11170552 DOI: 10.1021/jf0004762] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Fruit juices have very distinct organic acid profiles that can be used as fingerprints for establishing possible adulteration. Recently, our group developed and validated a capillary electrophoresis method using UV detection for determining citric, isocitric, tartaric, and malic acids in natural and commercial orange juices. Sample treatment consisted of only dilution and centrifugation or filtration. This method has been applied to evaluate these acids and their ratios in 63 samples of Navelina, the most common variety of Spanish oranges, over a three month period. This evaluation has been conducted to establish ranges of acid concentrations and to compare them with those found in commercial juices. The more reliable parameter, because of the lower variability in fresh samples, was found to be the citrate/isocitrate ratio with a value of 113 (RSD = 10%). Only one of nine ramdonly selected commercial juices presented values within the range of those of the population of just-pressed Navelina orange juice. Moreover, three of them had measurable tartrate values, which is not a natural component of orange juice, showing mixtures with cheaper fruits.
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Affiliation(s)
- L Saavedra
- Facultad de CC Experimentales y Técnicas, Universidad San Pablo-CEU, Urbanización Montepríncipe, Ctra. Boadilla del Monte, km 5,3 - 28668 Madrid, Spain
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24
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Molnár-Perl I. Role of chromatography in the analysis of sugars, carboxylic acids and amino acids in food. J Chromatogr A 2000; 891:1-32. [PMID: 10999622 DOI: 10.1016/s0021-9673(00)00598-7] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An overview is presented of chromatographic methods currently in use to determine sugars, carboxylic acids and amino acids in foods: high-performance liquid chromatography, gas chromatography and capillary electrophoresis. As a basis of selection the following approaches can be distinguished: quantitation of constituents of several food matrices, without derivatization and in the form of different derivatives, in the presence of the matrix, or subsequently to various work-up procedures.
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Affiliation(s)
- I Molnár-Perl
- Institute of Inorganic and Analytical Chemistry, L. Eötvös University, Budapest, Hungary.
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25
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Saavedra L, García A, Barbas C. Development and validation of a capillary electrophoresis method for direct measurement of isocitric, citric, tartaric and malic acids as adulteration markers in orange juice. J Chromatogr A 2000; 881:395-401. [PMID: 10905722 DOI: 10.1016/s0021-9673(00)00258-2] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Fruit juices each have very distinct organic acids profiles that can be used as fingerprints for establishing authenticity. A method has been developed, optimised and validated for measuring by capillary electrophoresis citric, isocitric, malic and tartaric acids as authenticity markers in orange juices, without any sample treatment other than dilution and filtration. Final conditions were phosphate buffer 200 mM, pH 7.50, -14 kV as applied potential, and 57 cm length neutral capillary. Detection was direct UV at 200 nm. Different kinds and marks of orange juice, chosen from the great variety existent in the market, were analysed and clear differences could be found between them and just pressed orange juice.
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Affiliation(s)
- L Saavedra
- Facultad de CC Experimentales y Técnicas, Universidad San Pablo-CEU, Urbanización Montepríncipe, Madrid, Spain
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26
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Masson P. Influence of organic solvents in the mobile phase on the determination of carboxylic acids and inorganic anions in grape juice by ion chromatography. J Chromatogr A 2000; 881:387-94. [PMID: 10905721 DOI: 10.1016/s0021-9673(00)00164-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Investigations have been initiated to develop a sufficiently good separation of both major and minor organic acids and inorganic anions present in grape musts using a Dionex As11 column, a sodium hydroxide gradient elution and a suppressed conductivity detection. Separation was complicated in aqueous mobile phase by co-elutions and selectivity was optimized using organic modifiers that alter ion-exchange selectivity for hydrophobic ions. In this study, the influence of three different solvents (methanol, ethanol and acetonitrile) on the efficiency of column was compared. The best separation of all ions in a synthetic solution was achieved with an eluent containing 13% (v/v) methanol and 13% (v/v) ethanol in water, the run during only 20 min. This method was next applied to grape juices with success and has shown sensitivity and reproducibility. Moreover, sample preparation was a simple 20-fold dilution with 0.45 microm filtration and direct injection without prior sample clean-up.
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Affiliation(s)
- P Masson
- Station d'Agronomie, Centre de Recherches INRA de Bordeaux, Villenave d'Ornon, France
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27
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Ahrer W, Buchberger W. Analysis of low-molecular-mass inorganic and organic anions by ion chromatography-atmospheric pressure ionization mass spectrometry. J Chromatogr A 1999; 854:275-87. [PMID: 10497946 DOI: 10.1016/s0021-9673(99)00396-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Different nonvolatile mobile phases have been tested for the combination of ion-exchange chromatography combined with mass spectrometric detection of anions and organic acids. Buffer systems based on carbonate, sulfate, oxalate and citrate as the eluting species have been used. Among these, citrate proved to be the most versatile eluent allowing the separation of anions with absolute detection limits between 0.4 and 0.7 ng and of organic acids with detection limits between 0.4 and 4 ng in the non-suppressed mode. In the suppressed eluent mode iodate, bromate and chlorate could be separated using sodium carbonate as the mobile phase resulting in detection limits of 50 pg. The method was applied to the analysis of water samples containing oxyhalides originating from ozonization. Additionally, organic acids were separated by chromatographic separation techniques like reversed-phase, ion-pair or ion-exclusion chromatography and the compatibility with mass spectrometry was investigated with special respect to sensitivity of this detection mode.
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Affiliation(s)
- W Ahrer
- Department of Analytical Chemistry, University of Linz, Austria
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28
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Yamamoto A, Inoue Y, Kodama S, Matsunaga A. Capacity gradient anion chromatography with a borate complex as eluent. J Chromatogr A 1999; 850:73-7. [PMID: 10457467 DOI: 10.1016/s0021-9673(99)00493-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Complex formation between borate compounds and vicinal diols is well recognized. Generally, in a chemically bonded anion-exchange resin, many hydroxyl groups are introduced on the surface of the resin in order to make the resin hydrophilic. The borate as an eluting reagent also reacts to these hydroxyl groups, and this complex formation decreases the apparent ion-exchange capacity of the column by being dissociated to the anion depending on the eluent pH. In the present work a method is described for the simultaneous determination of anions based on the capacity gradient for suppressed ion chromatography. A Tosoh IC-Anion-PW column and dihydroxyphenylborane-mannitol eluent system were used. To maintain baseline stability, it was helpful to keep the borate concentration constant during a gradient of 16 to 0 mM mannitol as a modifier to prevent the complex formation with the hydroxyl on the resin. The chemical composition of the eluents and gradient profiles are discussed and the application to the analysis of the condensed phosphates with widely varying retention times as food additives in a cheese sample is presented.
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29
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Hajós P, Nagy L. Retention behaviours and separation of carboxylic acids by ion-exchange chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 717:27-38. [PMID: 9832238 DOI: 10.1016/s0378-4347(98)00247-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The use of high-performance suppressed ion chromatography for the separation of aliphatic carboxylic acids has become an attractive and viable method during the past years. This paper summarises and critically concludes that some new results have been achieved in separation and detection of low-molecular-mass organic anions. Theoretical and practical considerations of ion-exchange selectivity to control retention behaviour are presented. The major factors that determine the separation ability of ion-exchange chromatography (pKa values, the aliphatic nature and valency of solutes, eluent pH and the chemical composition of stationary phases) are discussed. The question of isocratic vs. gradient elution and different separation modes are examined briefly. The potentials and limitations of the developed methods and their specific application areas are outlined.
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Affiliation(s)
- P Hajós
- Department of Analytical Chemistry, University of Veszprém, Hungary
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30
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Fu C, Song L, Fang Y. Simultaneous determination of sugars and organic acids by co-electroosmotic capillary electrophoresis with amperometric detection at a disk-shaped copper electrode. Anal Chim Acta 1998. [DOI: 10.1016/s0003-2670(98)00283-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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31
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Hettiarachchi K, Ridge S. Capillary electrophoretic determination of acetic acid and trifluoroacetic acid in synthetic peptide samples. J Chromatogr A 1998; 817:153-61. [PMID: 9764489 DOI: 10.1016/s0021-9673(98)00328-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Synthetic peptide samples may contain counter-ions such as acetate or trifluoroacetate as a result of their method of preparation. Furthermore, because acetic acid (HOAc) and trifluoroacetic acid (TFA) are frequently used reagents in peptide synthesis, these acids may be found in synthetic peptide samples as impurities. This paper describes a method validation to determine HOAc and TFA in synthetic peptide samples by capillary electrophoresis (CE) using an internal standard (I.S.) with indirect UV detection. Typical analytical parameters such as precision, linearity, accuracy, specificity, limit of detection and ruggedness were evaluated during the validation. In addition, the contents of HOAc and TFA in two synthetic opioid peptide samples, TIPP[psi] and Orphanin FQ, were determined using the validated method. A unique feature of the method is that it offers determination of both acids in a single assay using a common I.S. The method is very efficient because of relatively short electrophoretic migration times (typically 2 to 8 min) for the acids investigated. This paper also discusses the factors that affect precision in a CE assay.
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Affiliation(s)
- K Hettiarachchi
- Analytical Chemistry Department, SRI International, Menlo Park, CA 94025, USA
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32
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Casey C, O'Sullivan O, O'Gara F, Glennon J. Ion chromatographic analysis of nutrients in seed exudate for microbial colonisation. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(97)01297-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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33
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Buldini PL, Cavalli S, Trifirò A. State-of-the-art ion chromatographic determination of inorganic ions in food. J Chromatogr A 1997; 789:529-48. [PMID: 9440294 DOI: 10.1016/s0021-9673(97)00963-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A review of the applications of ion chromatography (IC) to the determination of inorganic ions in food is presented. The most promising sample preparation techniques, such as accelerated solvent extraction, supercritical fluid extraction, solid-phase extraction, UV photolysis, microwave-oven digestion and pyrohydrolysis are discussed. Among the various inorganic anions, nitrogen, sulphur and phosphorus species and halides are widely determined in foods and to a lesser extent only, cyanide, carbonate, arsenic and selenium species are considered. IC determination of inorganic cations deals with ammonium ion, alkali, alkaline-earth, heavy and transition metals particularly and only a small amount of literature is found on the other ones, like aluminium and plantinum. A particular advantage of IC over traditional techniques is the simultaneous determination of several species.
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34
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Barden TJ, Croft MY, Murby EJ, Wells RJ. Gas chromatographic determination of organic acids from fruit juices by combined resin mediated methylation and extraction in supercritical carbon dioxide. J Chromatogr A 1997; 785:251-61. [PMID: 9409006 DOI: 10.1016/s0021-9673(97)00411-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A procedure in which anionic analytes, trapped on ion exchange resin, are simultaneously methylated and released using methyl iodide in either supercritical carbon dioxide or acetonitrile has been extended to polyfunctional organic acids. The combined SFE methylation of fruit juice acids trapped onto ion exchange resin proceeds in good yield producing the methyl esters of fumaric, succinic, malic, tartaric, isocitric and citric acids which are readily separated by GC. Using this procedure low concentrations of one acid can be detected and quantitated in the presence of very high concentrations of another. This new method detects tartaric acid at levels of 10 ppm in juices containing 10,000 ppm citric acid. Quantitation was performed either by using GC-FID with triethyl citrate or diethyl tartrate as internal standards or with the element specific calibration capability of the GC-AED. A simple new technique for the determination of citric/isocitric acid ratio is now available. Also, in contrast to HPLC methods, the identity of an analyte is readily confirmed by GC-MS.
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Affiliation(s)
- T J Barden
- Australian Government Analytical Laboratories, Pymble, NSW 2073, Australia
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35
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Trifirò A, Saccani G, Gherardi S, Vicini E, Spotti E, Previdi MP, Ndagijimana M, Cavalli S, Reschiotto C. Use of ion chromatography for monitoring microbial spoilage in the fruit juice industry. J Chromatogr A 1997; 770:243-52. [PMID: 9203364 DOI: 10.1016/s0021-9673(97)00049-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Fruit juices and purees are defined as fermentable, but unfermented, products obtained by mechanical processing of fresh fruits. The presence of undesired metabolites derived from microbial growth can arise from the use of unsuitable fruit or from defects in the production line or subsequent contamination. This involves a loss in the overall quality that cannot be resolved by thermal treatment following the start of fermentation. With these considerations, together with microbiological control, the analysis of different metabolites, which can be considered as microbial growth markers, such as alcohols (i.e. ethanol, etc.), acids (i.e. acetic, fumaric, lactic, etc.) is fundamental in order to achieve a better evaluation of product quality. Enzymatic determination and other single-component analytical techniques are often used for the determination of these metabolites. When the microbial spoilage is not well known, this results in a long and cumbersome procedure. A versatile technique that is capable of determining many metabolites in one analysis could be helpful in improving routine quality control. For this purpose, an ion chromatographic technique, such as ion exclusion, for separation, and diode array spectrophotometry and conductivity, for detection, were evaluated. Both different industrial samples and inoculated samples were analyzed.
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Affiliation(s)
- A Trifirò
- Stazione Sperimentale per l'Industria delle Conserve Alimentari, Parma, Italy
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36
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Volgger D, Zemann AJ, Bonn GK, Antal MJ. High-speed separation of carboxylic acids by co-electroosmotic capillary electrophoresis with direct and indirect UV detection. J Chromatogr A 1997. [DOI: 10.1016/s0021-9673(96)00744-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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37
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Révész G, Hajós P, Csiszár H. Mixed-mode liquid chromatography of carboxylic acids and inorganic anions on a latex-based pellicular stationary phase. J Chromatogr A 1996. [DOI: 10.1016/s0021-9673(96)00644-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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