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Analysis and Separation of Organic Acids in White Wine Using HighPerformanceLiquidChromatography Atis,ArnelsonArwinG. andGaitos,GeraldM. set upofChemistry,UniversityofthePhilippines,Diliman,QuezonCity PerformedDecember9,2011 SubmittedDecember15,2011 RESULTSANDDISCUSSION solutions containing increasing amounts of the organic virulent. These solutions were contained in flasks numbered 5, 6, 7, 8, and 9. (Refer to the Appendix to see components of each flask).Tables 2, 3, 4, and 5 showthepeakareasandtheequationofthe calibration curve obtained for each organic acid in the chromatogramsobtainedforflasks5to9. Table2. teetotum field of operationssofTartaricAcidinFlasks5,6,7,8, and9 Flask Retention PeakArea dumbness time(min) (g/L) 5 2. 863 491364 0. 5 6 2. 905 918187 1 7 3. 027 5949164 5 8 3. 044 8363261 8 9 3. 065 9475446 10 calibrationCurve comparison y=984371. 3561x+216064. 755 R2=0. 9912 Table3. PeakAreasofMalicAcidinFlasks5,6,7,and 8 Flask Retention PeakArea constriction time(mi n) (g/L) 5 3. 02 159742 0. 5 6 3. 760 1114051 1 7 3. 756 4892727 5 8 3. 795 6883424 10 CalibrationCurveEquation y=688260. 8175x+475029. 6892 R2=0. 9766 Table 4. Peak Areas of Lactic Acid in Flasks 5, 6, 7, 8, and9 Flask Retention PeakArea Concentration time(min) (g/L) 5 3. 533 575620 0. 1 6 3. 598 1248888 1 7 3. 621 3762922 2. 5 The keeping times of different organic acids commonly found in white wine-coloured were obtained using high performance liquid chromatography.The peak areas of the acids were then obtained through chromatogramsandplottedagainsttheconcentrations of the standard solutions of the organic acids to construct a calibration curve. Finally, the calibration curves obtained were utilise to determine the concentration of the organic acids in samples of white wine. Standard solutions of various organic acids commonly found in white wine (tartaric, malic, lactic, citric) were assigned to be contained in flasks 1, 2, 3, and 4, respectively, and were run through the ch romatograph.Themobilephase utilizefortheanalytes was H3PO4 at pH 3, to prevent dissociation of the organic acids. The resulting chromatograms of each standard were then study to obtain the retention times of the organic acids. Table 1 shows the experimental retention times of the different organic acids. Table 1. Experimental Retention propagation of Organic Acids OrganicAcid RetentionTime(min) Tartaric 3. 088 Malic 3. 812 Lactic 3. 620 Citric 3. 68 Since there were no clear peaks from the chromatograms obtained for the tartaric, malic, and lactic acid samples, the retention time at which the peak height is greatest was obtained as the experimentalretentiontimeoftheorganicacids. The experimental retention times were then used to identify the peak areas corresponding to each organicacidanalyzedintheresultingchromatogramsof 8 3. 597 5048614 3 9 3. 619 6519896 5 CalibrationCurveEquation y=1300341. 246x+414396. 3089 R2=0. 9815 Table 5.Peak Areas of Citric Acid in Flasks 5, 6, 7, 8, and9 Flask Retention PeakArea Concentration time(min) (g/L) 5 3. 140 361921 0. 05 6 3. 208 907232 0. 1 7 3. 306 4736427 0. 5 8 3. 325 7508481 0. 75 9 3. 347 9612454 1 CalibrationCurveEquation y=9836731. 501x+96328. 12036 R2=0. 9994 The equations of the calibration curves were then used to calculate the concentration of each organic acid in the white wine samples. The peak area corresponding to each organic acid was first obtained, and substituted in the calibration curve equation.The concentrationofeachacidisshowninTable6. Table 6. Experimental Concentration of Various OrganicAcidsinWhiteWineSamples. Organic Retention PeakArea Concentration Acid Time(min) (g/L) Tartaric 2. 966 2675651 2. 499 Malic 3. 752 3576021 4. 506 Lactic 3. 393 4709737 3. 303 Citric 3. 144 794394 0. 091 Theresultsindicatethatmalicacidisthemajor componentofwhitewine. stillinreality,thisisnotthe case. Themajorcomponentofwhitewineisfoundtobe tartaricacid. The chromatograms (See Appendix) of flasks 1 to 9, and o f the sample are not well resolved.This divergency may be caused by several factors. These factors include poor solution preparation, contaminationofthesolventorthesample,bubblesin the detector, impurities in the mobile phase, bleeding ofthecolumn, short-staffedadjustmentofequilibriumin gradient operation, and carry? over from previous injection. Duetothesefactors,itishighlyadvisedthatthe future researchers should cautiously execute each performance of the experiment to eliminate the discrepancy and accordingly, they could attain better results.They could also make use of theoretical retentiontimesoftheorganicacidstodetermineeach of them and which could push help the future researchers to analyze the wine sample more efficiently. REFERENCE Meyer,VeronikaR. PracticalHighPerformanceLiquid Chromatography. 2nded. 1993. EnglandJohn Wiley&SonsLtd. APPENDIX entropySheets Concentrationoftartaricacidstandard50. 0g/L Concentrationofmalicacidstandard50. 0g/L Concentrationoflacticacidsta ndard25. 0g/L Concentrationofcitricacidstandard5. 0g/L CompositionofFlasks1? 9 Volumeofstandardstocksolutions(inmL) RetentionTimeMeasurement CalibrationCurve Flask 1 2 3 4 5 6 7 8 TartaricAcid 5. 00 0. 00 0. 00 0. 00 0. 25 0. 50 2. 50 4. 00 MalicAcid 0. 00 7. 50 0. 00 0. 00 0. 10 0. 50 2. 50 5. 00 LacticAcid 0. 00 0. 00 5. 00 0. 00 0. 10 1. 00 2. 50 3. 00 CitricAcid 0. 00 0. 00 0. 00 5. 00 0. 25 0. 50 2. 50 3. 75 9 5. 00 7. 50 5. 00 5. 00 *Chromatogramsofflasks1? 9andofthewhitewinesample basisbeseenintheremainingpagesafterthis.