Characterization of odour active compounds in strawberry vinegars

1 Depósi o de in es igación de la Uni e sidad de Se illa h ps://idus.us.es/ “This is he pee e iewed e sion o he ollowing a icle: Ubeda, C., Callejón, R.M., T oncoso, A.M., Mo eno-Rojas, J.M., Peña, F. and Mo ales, M.L. (2012), Cha ac e iza ion o odou ac i e compounds in s awbe y inega s. Fla ou F ag . J., 27: 313-321, which has been published in inal o m a h ps://doi.o g/10.1002/ j.3103. This a icle may be used o non-comme cial pu poses in acco dance wi h Wiley Te ms and Condi ions o Use o Sel - A chi ed Ve sions. This a icle may no be enhanced, en iched o o he wise ans o med in o a de i a i e wo k, wi hou exp ess pe mission om Wiley o by s a u o y igh s unde applicable legisla ion. Copy igh no ices mus no be emo ed, obscu ed o modi ied. The a icle mus be linked o Wiley’s e sion o eco d on Wiley Online Lib a y and any embedding, aming o o he wise making a ailable he a icle o pages he eo by hi d pa ies om pla o ms, se ices and websi es o he han Wiley Online Lib a y mus be p ohibi ed." 2 Ti le: CHARACTERIZATION OF ODOUR ACTIVE COMPOUNDS IN STRAWBERRY VINEGARS Au ho s: C. Ubeda1, R.M. Callejón1, A.M. T oncoso1, J.M. Rojas2, F. Peña2, M.L. Mo ales1* Add ess: 1Á ea de Nu ición y B oma ología. Facul ad de Fa macia. Uni e sidad de Se illa. c/ P. Ga cía González nº2, E- 41012. Se ille. Spain. 2IFAPA Cen o Alameda del Obispo. A da. Menéndez Pidal s/n, E-14004. Có doba. Spain. *Co esponding au ho : e-mail: [email p o ec ed]; Tel.: 34-954-556760; Fax.: 34-954- 233765 Abs ac Odou -ac i e compounds in s awbe y inega s we e de e mined by gas ch oma og aphy equipped wi h an ol ac ome e (GC-O) using he modi ied equency (MF) echnique. The ini ial s awbe y subs a e was also analysed showing ha e hyl 2- me hylbu y a e, mesi u ane, β-damascenone, u aneol and γ-decalac one we e p ese ed du ing he double e men a ion p ocess, p esen ing high MF alues. The inal a oma ic p o ile o s awbe y inega s is o med bo h by compounds om he subs a e and by hose o med du ing alcoholic and ace ous e men a ion. Due o hei high MF, a o al o 12 odou zones, iden i ied as ace ic, bu y ic and iso ale ic acids, me hional, 3-nonen-2- one, 2-phenyle hanol, pan olac one+ u aneol, p- inylguaiacol, so olon, phenylace ic acid and anillin, we e conside ed as possible impac odo an s o s awbe y inega s. Finally, all po en ial impac odo an s wi h simila senso y desc ip o s we e g ouped in o 8 ca ego ies, hese being: ui y, swee , g assy, spicy, bu e -lac ic-cheesy, chemical, empy euma ic and miscellaneous. Acco ding o he MF pe cen age o hese ca ego ies, 3 g assy, ui y, swee and spicy a oma seem o ha e he highes in luence on he o e all imp ession o s awbe y inega s. Keywo ds: impac odo an , ol ac ome y, inega , s awbe y, modi ied equency. In oduc ion Because o i s wo ldwide a ailabili y and i s g ea a ay o a ie ies, inega is one o he wo ld’s mos widesp ead and common p oduc s. In Spain, inega is mainly p oduced by he double e men a ion (alcoholic and ace ous) o g apes. P esen , inno a ions in inega p oduc ion alls in o wo a eas: imp o ing p oduc ion p ocesses and employing di e en aw ma e ials. S awbe ies a e p ized o bo h hei a oma and la ou . Spain is he wo ld’s second la ges s awbe y p oduce . Since he e a e su pluses o second quali y s awbe y, his makes i an a ac i e candida e o use as a aw ma e ial in p oducing new kinds o inega s. A oma is ce ainly one o he mos impo an de e minan s in ood quali y and accep ance[1]. The e o e, when in oducing a new ood p oduc , he cha ac e iza ion o i s a oma is an impo an aspec o be conside ed. A oma is de e mined by a la ge numbe o compounds ha a e in ol ed in di e en ways. Among he abo e, odou - ac i e compounds play an impo an ole in pe cei ed a oma and especially, impac odo an s, ha di ec ly in luence in i . An essen ial ool when cha ac e izing he ol ac o y impac o an odo an (i s odou desc ip o and in ensi y) is he coupling o Gas Ch oma og aphy/Ol ac ome y (GC/O)[2]. Among he di e en ypes o ol ac ome ic analysis, he h ee main ones a e: dilu ion me hods, pe cei ed in ensi y me hods and equency o de ec ion me hods. The equency o de ec ion has been p o ed o p o ide quan i a i e es ima es o he senso y impo ance o a compound [3] and has e en been p o ed o be accu a e enough o 4 p o ide a eal quan i a i e da a[4], bu i s limi ed due o he ac ha once he concen a ion becomes highe han he less sensi i e membe o he panel, he signal becomes sa u a ed[5]. This limi a ion can be pa ly o e come by combining he equency o de ec ion wi h a simple measu emen o in ensi y, which also has been p o ed o p o ide eliable quan i a i e da a[6]. As concen a ion inc eases, odou in ensi y may con inue o inc ease, howe e he equency o de ec ion migh no inc ease when all membe s o he panel a e inally able o de ec he odo an [5]. The combina ion o in ensi y and equency o de ec ion can be done h ough he so called modi ied equency (MF) which is he geome ic mean o he de ec ion equency o an a oma ic zone (exp essed as a pe cen age) and he a e age in ensi y (exp essed as a pe cen age o he maximum in ensi y)[7]. This concep is use ul because he disc imina i e capabili ies o he de ec ion equency may be imp o ed by aking in ensi y in o accoun [8] and, mo eo e , because he membe s o a as ing panel can ha e widely di e gen sensi i i ies[7]. MF, he e o e, p o ides mo e eliable esul s. The ola ile composi ion o s awbe y has been he objec o ex ensi e s udy. The a oma o his ui is gene ally a complex mix u e o es e s, u anones, and e pene alcohols wi h smalle amoun s o lac ones, aldehydes, alcohols and sulphu compounds[9-16]. Among he abo e, u aneol and mesi u ane a e conside ed o be he wo majo la ou con ibu o s due o hei low odou h eshold and hei high quan i ies[17]. These compounds ha e been con i med in se e al s udies on he odou - ac i e compounds in di e en s awbe y a ie ies. In hese wo ks, he au ho s ha e iden i ied a conside able numbe o odou -ac i e compounds and hey ag ee on u aneol, mesi u ane and γ-decalac one as being impac odo an s in s awbe y[18,19]. In his wo k we ha e de e mined odou -ac i e compounds and he possible impac odo an s by GC-O in s awbe y inega s ob ained h ough double e men a ion. 5 Mo eo e , an ol ac ome ic analysis o he s a ing subs a e has been also pe o med o asce ain whe he he key odo an s o aw ma e ial emain in he inal p oduc s. Expe imen al Chemicals Dichlo ome hane and anhyd ous sodium sulpha e we e pu chased om Me ck (Da ms ad , Ge many), all o hem we e o analy ical quali y. S awbe y inega samples Vinega s analyzed in his s udy we e p oduced om second quali y s awbe ies o Cama osa a ie y. Fo ha pu pose, ui was c ushed and mixed wi h pec oly ic enzymes and sulphu dioxide. Besides, 50 g/L o suc ose we e added o ensu e an app op ia e inal acidi y in he esul ing inega . This s a ing subs a e (F8P2) was submi ed o wo ypes o alcoholic e men a ions, spon aneous and inocula ed wi h he yeas Saccha omyces ce e isiae QA23 a a concen a ion o 2x106 cells/mL. All esul ing wines we e spon aneously ace i ied by su ace cul u e. Thus, we ob ained wo di e en inega s: F8VI ( om inocula ed alcoholic e men a ion) and F8VE ( om spon aneous alcoholic e men a ion). Sample ex ac ion The liquid-liquid ex ac ion me hod was pe o med o ob ain a ep esen a i e ex ac o he samples[9]. The p ocedu e ollowed was: 5 g o anhyd ous sodium sulpha e was added o 50 mL o each sample and was ex ac ed wice du ing 5 minu es wi h 5 mL o dichlo ome hane using a magne ic s i ba . Then, 2.5 mL o he o ganic phase was concen a ed 5 imes unde a ni ogen s eam. Gas Ch oma og aphy-Ol ac ome y condi ions (GC-O) Analyses we e conduc ed using a Va ian 3800 GC (Middelbu g, The Ne he lands) equipped wi h a lame ioniza ion de ec o (FID) and an OP275 ol ac ome e (GL 6 Science Inc., Tokyo, Japan). Two mic oli e s o each ex ac we e injec ed in spli less mode in o a DB-WAX column wi h 60 m x 0.25 mm x 0.22 μm ilm hickness (J & W Scien i ic, Agilen Technologies Inc., San a Cla a, USA). The o en empe a u e p og am was as ollows: 40° o 1 min, inc easing o 220 °C a a a e o 2°C/min and held o 30 min. The column e luen was spli 2:3 in o a FID and a hea ed sni ing po . The injec o and de ec o empe a u e was 220ºC. The ca ie gas was H2 a a low a e o 1 mL/min. The senso y panel was composed o h ee ained as e s, all o hem sni ed each sample wice, assigning o each pe cei ed odou an in ensi y le el: 1, 2 o 3. Resul s we e exp essed as “modi ied equency” (MF), calcula ed wi h he o mula p oposed by D a nieks[20]. Gas Ch oma og aphy-Mass Spec ome y (GC-MS) condi ions Analyses we e conduc ed using an Agilen 6890 GC sys em coupled o an Agilen 5975ine quad upole mass spec ome e and equipped wi h a Ge s el MP2 headspace au osample (Müllheim an de Ruh , Ge many). The analy ical column was a CP-Wax 57CB column o 50 m × 0.25 mm and 0.20 µm ilm hickness (Va ian, Middelbu g, The Ne he lands). The injec o po was hea ed o 220°C and 2 L o sample ex ac we e injec ed in spli less mode wi h a pu ge low o 70 mL/min and pu ge ime o 2 minu e. The ca ie gas was He a a low a e o 1 mL/min. The o en empe a u e p og am was he same employed in GC-O. Quad upole, sou ce and ans e line empe a u es we e 150, 230 and 250 °C, espec i ely. Elec on ioniza ion mass spec a da a om m/z 29~350 we e collec ed in he scan mode, wi h an ioniza ion ol age o 70 eV. Iden i ica ion o A oma Compounds In he GC-MS analysis, ola ile compounds we e iden i ied based on he compa ison o he e en ion imes o indi idual s anda d and compu e ma ching wi h he e e ence mass spec a om he NIST 98 lib a y. 7 In he GC-O analysis, compounds we e iden i ied by he compa ison o hei linea e en ion indices (LRIs) wi h hose ob ained in GC-MS analysis o ex ac and s anda ds as well as wi h LRIs and odou quali ies om Fla o ne (www. la o ne .o g)[21] and Phe obase (www.phe obase.com)[22] online da a bases and li e a u e[9,23-38]. Linea e en ion indices (LRIs) we e calcula ed on he basis o e en ion imes o n- alkanes (C10–C32) unde iden ical condi ions o each ins umen . S a is ical analysis All s a is ical analyses we e pe o med using S a is ica so wa e e sion 7.0 so wa e package (S a so , Tulsa, USA). A p incipal componen analysis (PCA) was ca ied ou as an unsupe ised me hod in o de o asce ain he deg ee o di e en ia ion be ween samples and which compounds we e in ol ed. Resul s and Discussion In his s udy, we only conside ed hose odou zones which we e de ec ed in a leas hal o he o al sni ing ials as odou -ac i e. The odou zones and hei co esponding iden i ica ion a e lis ed in Table 1, some o hem we e only en a i ely iden i ied (TI). Thus, GC-O analyses e idenced 79, 55 and 49 odou -ac i e zones in subs a e, F8VI and F8VE inega s espec i ely. In he subs a e, he odou zones ha p esen ed maxima MF (100) we e hose which we e iden i ied as me hyl bu y a e (LRI 990, TI), isoamyl alcohol (LRI 1208), cis-2- nonenal (LRI 1504, TI), γ-decalac one (LRI 2150) , γ-dodecalac one (LRI 2382) and anillin (LRI 2564, TI). Some ha e been p e iously epo ed as impo an componen s in s awbe y a oma. Thus, me hyl bu y a e is one o he majo es e s p esen in his ui [39,40]. Acco ding o Gomes da Sil a and Cha es das Ne es[41], p ominen lac ones we e γ-decalac one and γ–dodecalac one, gi ing ui y no es. Cis-2-nonenal has been desc ibed as a equen odo an p esen in di e en s awbe y a ie ies[42]. On he o he 8 hand, he p esence o anillin among he a oma compounds in s awbe y has been sca cely obse ed by o he au ho s[43,44] and un il now i had been desc ibed as an odou -ac i e compound in one a ie y only [45]. As expec ed, u aneol (LRI 2034) and i s me hoxy de i a i e[46], mesi u ane (LRI 1594), he s awbe y componen s mos quo ed as cha ac e impac compounds, also eached high MF; 91 and 75, espec i ely. Wi hin hose odou zones which eached high MF, we can highligh hose ha we ha e en a i ely iden i ied o he i s ime in s awbe y such as 2,6-dime hylpy azine (LRI 1305), 2- u u yl hiol (LRI 1433), guaiacol (LRI 1881), 6,7-dyhyd o-7-hyd oxylinalool (LRI 1971), 4-e hylphenol (LRI 2183), so olon (LRI 2203) and e hyl hexadecanoa e (LRI 2270). The i s wo odo an s and so olon a e ypical compounds p oduced by he Mailla d eac ion[47-49]. The p esence o hese compounds may be due o he same o ma ion pa hway, since s awbe y has educing suga s as well as amino acids. Mo eo e , sni e s also pe cei ed some o -odou a ibu es en a i ely iden i ied as ola ile phenols wi h high MF: guaiacol and 4-e hylphenol. Se e al au ho s poin o hese compounds as o - la ou s in di e en ood ma ices[50,51]. Mo eo e , hey a e ela ed o ui con amina ion caused by di e en mic oo ganisms[52,53]. In addi ion o he abo e-men ioned compounds, we ound o he impo an odou zones wi h MF highe han 70, p o iding ui y no es, co esponding o ypical s awbe y es e s (e hyl bu y a e (LRI 1029) and e hyl hexanoa e (LRI 1234, TI)). Fu he mo e, we iden i ied linalyl ale a e/ci onellol (LRI 1766, TI) and ne olidol (LRI 2003) a ound his MF alue, gi ing g assy and ci ic a oma cha ac e s. Among he 38 odou zones wi h a signi ican con ibu ion o he a oma (MF>70), we we e, e en en a i ely, unable o iden i y ou o hem. 9 The compa ison o ol ac ome ic analysis esul s o subs a e and inega s showed ha a o al o 29 odo an s p esen in he s awbe y pu ee we e de ec ed bo h in inega s p oduced om wines whose subs a e had been inocula ed and hose which had been ob ained om spon aneous e men a ion. These odo an s we e, he e o e, p ese ed h oughou he double e men a ion p ocess. Mos o hem, howe e , p esen ed lowe MF alues in inega han in he subs a e due o he losses and ans o ma ions unde gone du ing he alcoholic and ace ous e men a ions[54,55]. The a oma ic p o ile o wine inega s is he esul o he pe manence o hose ola ile compounds om he aw ma e ial (g ape a ie als a oma), syn hesized by yeas du ing alcoholic e men a ion and hose o med du ing he ace ous e men a ion. The esul s showed ha a e he double e men a ion, some cha ac e is ic compounds o s awbe y[27,56] such as: γ-decalac one, u aneol, mesi u ane, β-damascenone (LRI 1821) and e hyl 2-me hylbu y a e (LRI 1040) we e p ese ed om he aw ma e ial o bo h inega s. Su p isingly, mo eo e , hey eached high MF alues. On he o he hand, he impac odo an s o s awbe y, e hyl bu y a e and γ- dodecalac one, we e only pe cei ed in inega p oduced om wine ob ained by inocula ion o he subs a e while me hyl bu y a e was pe cei ed only in inega om wine ob ained by spon aneous e men a ion. These esul s indica e ha he o e all odou imp ession o inega would e oke a oma ic no es o he aw s awbe y ma e ial used. Mo eo e , we obse ed he appea ance o odou zones, o an inc ease in he MF sco es o o he odou zones co esponding o compounds usually o med in ace ous e men a ion[9,57]. The e o e, a oma ic no es such as bu e (diace yl, LRI 970) and pungen (ace ic acid, LRI 1405), appea ed in he inega s. 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Helinck, P. Bonna me, Appl. Mic obiol. Bio echnol. 2008, 77, 1191. 18 Figu e Cap ions Figu e 1. Da a sco es (MF) (a) and a iable loadings (b) plo s on he planes made up o he fi s wo p incipal componen s (PC1 agains PC2). The compound names co esponding o he numbe o a iables a e loca ed in Table 1. Figu e 2. Con ibu ion o each a oma ca ego y as a pe cen age o he o al MF o odou zones ha migh be po en ial impac odo an s in a leas one sample. 19 Table 1. Odou ac i e compounds in s awbe y subs a e and ob ained inega s. LRI DB-Wax LRI CP-Wax o /and li e a u e Odou Desc ip o Odo an d Fa FMb Fa FMb Fa FMb Iden i ica ionc Subs a e Inocula ed Spon aneous 934 - s awbe y acid unknown - - - - 3 41 - 963 961e plas ic, syn he ic e hyl p opiona e - - 3 41 3 41 MS, OD 970 969[9];970[23,24] bu e diace yl - - 4 67 4 67 LRI, OD 990 990[21] s awbe y me hyl bu y a e1 6 100 - - 6 100 LRI, OD 1012 1012e; 1014[25] medicinal isobu yl ace a e 4 47 - - - - LRI, MS, OD 1020 1022[21] ui , s awbe y, pineapple me hyl iso ale a e2 6 71 - - - - LRI, OD 1029 1029e;1032[24] banana, s awbe y, soap e hyl bu y a e3 5 75 5 53 - - LRI, MS, OD 1040 1040e,1041[26] banana, ui e hyl 2-me hylbu y a e4 6 82 6 58 6 82 LRI, MS, OD 1055 1055e,1056[26] ui , s awbe y, banana e hyl iso ale a e 4 67 3 41 3 41 LRI, MS, OD 1066 1067[22];1069[27] me allic, ubbe , swea hexanal5 5 75 - - - - LRI 1069 - oas ed b ead, co ee unknown6 5 75 - - - - - 1083 1083e,1084[9,28] ubbe , swea , la ex isobu anol 4 67 - - - - LRI, MS, OD 1105 1105e banana isoamyl ace a e 3 41 - - - - MS, OD 1144 1146e,1145[21] /1145[21] boiled po a o, ege able, g ass 1-bu anol/my cene7 6 82 3 58 3 41 LRI, MS, OD/ LRI, OD 1166 1169[29] g een, plas ic, ubbe , limonene 3 41 - - - - LRI, OD 1183 1181[30]/1185[25] swee , medicinal, aspi in me hyl hexanoa e/e hyl 3- me hylpen anoa e 4 47 - - - - LRI, OD 1208 1205,1208[21]; 1212e ancid, ubbe , chemical isoamyl alcohols(2-me hyl-1- bu anol+3-me hyl-1-bu anol)8 6 100 4 47 6 58 LRI, MS, OD 1220 1220[21] plas ic 2-hexenal 4 67 - - - - LRI, OD 1224 - chicken, cooked, syn he ic, ege able unknown - - 3 41 - - - 20 1234 1230e,1240[30] s awbe y, blackbe y, ci us, iole e hyl hexanoa e9 5 75 - - - - LRI, MS, OD 1247 - ege able, plas ic, lowe unknown 3 41 - - - - - 1264 1269[31] boiled po a o, boiled ege able α- e pinolene 4 58 - - - - LRI,OD 1289 - me allic, pain unknown - - - - 3 41 - 1302 1303[25];1306[24] plas ic, cooked ege able, me allic 1-oc en-3-one 5 53 - - - - LRI, OD 1305 1308[21] oas ed co n, boiled po a o 1-oc en-3-one+2,6- dime hylpy azine10 5 75 4 47 5 53 LRI, OD/ LRI, OD 1317 1315[25] ba becue 2-me hyl-3- u an hiol - - 3 58 5 53 LRI, OD 1327 1331[33] oas ed, chicken soup, dai y p oduc , plas ic 2-ace yl-1-py olidone - - - - 6 58 LRI, OD 1347 1345[21]/1345[21] ege able, g ass 2-oc enal/3-nonenal 3 41 - - - - LRI, OD 1350 1350[28]; 1355[34]; 1357e plas ic 1-hexanol 3 58 - - - - LRI, MS, OD 1373 1368[24];1377[34]/ 1377[21] g een lea , ish dime hyl isul ide/ ans-2-hexenol11 6 71 - - - - LRI, OD/LRI, OD 1391 - baked po a o, ege able unknown 3 58 - - - - - 1396 1394[25, 30]; 1396e baked po a o, mush oom cis-3-hexenol12 5 75 3 41 3 41 LRI, MS, OD 1405 1405e pungen ace ic acid13 - - 6 82 6 82 MS, OD 1419 1424[25] anise, swee , plas ic doll e hyl cyclohexanoa e 5 53 - - - - LRI, OD 1433 1436[25] oas , co ee 2- u u yl hiol14 6 82 - - - - LRI, OD 1435 1432e;1436[21] ui , s awbe y, lemon e hyl oc anoa e 3 58 3 41 - - LRI, MS, OD 1450 1449[35]/1452[25] baked po a o me hional15 - - 6 100 4 82 LRI, OD 1463 1568 s awbe y, banana, anilla, swee benzaldehyde - - 3 41 - - MS, OD 1500 - oas , bu ned, ho i on unknown 3 41 - - - - - 1502 - ege able, baked po a o, o ange unknown 3 58 - - - - - 1504 1502[35] oas ed, ege able, i e wa e cis-2-nonenal16 6 100 4 47 3 41 LRI, OD 1508 1511[36] i e wa e , apou 3-nonen-2-one17 4 67 5 91 5 91 LRI, OD 1535 1534e plas ic, ancid 2-(me hyl hio)e hanol 3 58 - - - - MS, OD 1560 1560[30] g ass, boiled g een beans, lowe linalool 4 67 - - - - - 1563 1563[21]; 1565e cheese, omi isobu y ic acid - - - - 4 58 LRI, MS,OD 21 1581 1575[21] iole , lowe , ege able, soap E,Z-2,6-nonadienal18 6 82 4 75 3 71 LRI, OD 1594 1584[22]; 1592e ca amel, swee , co on candy mesi u ane19 5 75 3 41 6 71 LRI, MS, OD 1611 - i e wa e , ancid unknown 3 58 - - - - - 1616 - cu g ass, i e wa e unknown 3 50 - - - - - 1619 1621[25] oas ed, peanu , ancid 2-ace ylpy azine 3 58 - - - - LRI, OD 1623 1623e; 1632[35] cheese, omi bu y ic acid 6 82 6 82 6 82 LRI, MS, OD 1648 1645[21];1647e i e wa e , ui compo e, swee , plas ic ace ophenone 3 41 - - 3 41 LRI, MS, OD 1669 1665[21] cheese iso ale ic acid20 5 53 6 100 6 100 LRI, OD 1692 1692e ui , lowe , plas ic, apou γ-hexalac one 3 41 - - - - MS, OD 1700 1702e; 1711[22] cu g ass, soap, plas ic, lowe α- e pineol 4 67 4 47 - - LRI, MS, OD 1715 1718e;1706[37] plas ic doll, anise benzyl ace a e21 5 75 - - - - LRI, MS, OD 1721 1720[21] min , lemon, ege able ca one 5 65 5 53 3 58 LRI, OD 1731 1731e;1738[38] plas ic, i e wa e me hionol 3 58 4 67 - - LRI, MS, OD 1740 - plas ic, bi umen, pneuma ic unknown 4 67 - - 4 58 - 1766 1765[21]/1762[21]; 1769[34] ancid, lowe , ci ic, esh linalyl ale a e/ci onellol22 5 75 - - 3 41 LRI, OD/ LRI, OD 1785 1784[21] min , plas ic e hyl salicyla e 3 58 - - - - LRI, OD 1810 - plas ic, peanu , ba becue unknown23 3 58 5 75 4 67 - 1821 1818[25] ui p ese e, quince compo e, oas apple -damascenone24 6 82 5 75 3 58 LRI, OD 1824 1823e;1829[21] min , lowe , jasmine 2-phenyle hanol ace a e - - 4 58 - - LRI, MS, OD 1836 lico ice, cu y, spicy unknown25 - - 6 82 - - - 1844 1838e;1842[21] plas ic, swea , dung, ancid e hyl dodecanoa e26 5 75 - - - - LRI, MS, OD 1861 1864[25] i e wa e , oli e, clo e, ba becue guaiacol27 6 82 4 67 4 67 LRI, OD 1877 1880e boiled po a o, me allic, min , iole benzyl alcohol 4 58 - - 4 58 MS, OD 1915 1916[25] ose, hyacin h 2-phenyle hanol28 5 53 6 71 5 75 LRI, MS, OD 1919 1920e coconu , swee hyd oxycinnamyl ace a e - - 3 41 - - MS, OD 1926 - cu g ass, lima beans, gasoline unknown 29 5 75 - - - - - 1941 - chamomile, u ine unknown - - 4 67 - - - 1957 - lemon, baked po a o unknown 3 41 - - - - - 22 1967 1967[34] ipe ui , quince compo e, oas apple δ-oc alac one - - 4 47 - - LRI, OD 1971 1972e lemon, washing powde , g een beans, g ass 6,7-dihyd o-7-hyd oxylinalool30 6 82 - - - - MS 1988 - ca amel, me allic, swee , honey unknown 3 41 - - 4 58 - 2003 2009[21]/2006[27]; 2010[22] soap, ege able ans-ne olidol/cis-ne olidol31 5 75 3 41 - - LRI, MS, OD 2034 2034e;2033[21]/ 2033[33] co on candy, ca amel, quince pan olac one+ u aneol32 6 91 6 100 5 75 LRI, MS, OD 2054 - swea , g ass, s agnan wa e unknown 33 5 75 - - - - - 2064 - g een beans, baked po a o, ancid oil unknown34 5 75 - - - - - 2085 2084[35]/2091[25] empe a, bu ned plas ic p/m-c esol 35 - - 5 75 - - LRI, OD 2150 2157e;2165[38] ui , blackbe y, peach γ-decalac one36 6 100 6 100 4 67 LRI, MS, OD 2155 - men hola ed unknown - - 3 58 2 47 - 2167 2170e; 2159[28]; 2176[25] clo e, sponge cake eugenol37 6 82 3 41 - - LRI, MS, OD 2183 2182[35]; 2185[25] empe a, cucumbe 4-e hylphenol38 4 75 5 75 3 58 LRI, OD 2196 2198[21] coconu , clo e, oas ed p- inylguaiacol39 4 75 6 82 5 91 LRI, OD 2203 2203[22]; 2204[25] lico ice, cu y so olon40 3 71 6 82 4 82 LRI, OD 2219 2216[22] liquo δ-decalac one41 - - - - 3 71 LRI, MS, OD 2230 2223[21]/2234[38] g ass, banana, ui , honey o-aminoace ophenone - - 3 41 3 58 LRI, OD 2241 2247[21] spice, coconu , lowe , oas ege able abhexone42 4 67 5 75 3 58 LRI, OD 2270 2269e empe a, ba becue, bu ned plas ic e hyl hexadecanoa e43 4 75 5 75 - - MS, OD 2319 - min , lemon, oo hpas e, ui unknown 4 47 3 58 3 58 - 2382 2384[21]; 2385e apple, ap ico , s awbe y, swee , milk γ –dodecalac one 44 6 100 4 58 - - LRI,MS, OD 2396 - banana, lowe , clo e unknown 4 47 - - 3 58 - 2437 2426[21] i e wa e , clo e, spicy, ba becue δ –dodecalac one45 4 82 6 58 - - LRI, OD 2455 2452e swee , cinnamon couma an - - 4 58 - - MS, OD 2490 - plas ic, bleach, ancid unknown 4 67 - - - - - 2545 - swee , coconu unknown - - 4 67 - - - 2556 2251[21];2553e[37] ose, honey phenylace ic acid46 4 75 6 100 5 91 LRI, OD 2564 2569[22] anilla, ca amel anillin47 6 100 5 75 4 75 LRI, OD 23 2600 2598[21] honey, anilla me hyl anilla e - - 3 58 - - LRI, OD 2636 - Compo e, banana, s awbe y unknown 3 41 - - - - - 2644 2640[21] honey ace o anillone - - 3 71 - - LRI, OD aF: F equency o occu ence bMF: Modi ied equency. cLRI: Inden i ied by Lineal Re en ion Index; MS: Iden i ied by ma ching mass spec a o GC-MS analysis o ex ac wi h hose om he NIST 98 lib a y; OD: Odou desc ip o . dCo esponding numbe o his compound in Figu e 1. eLRI in column CP-Wax 57CB o compound iden i ied by GC-MS. 24 Figu e 1a Subs a e Inocula ed Spon aneous -6 -4 -2 0 2 4 6 8 Fac o 1: 73,42% -5 -4 -3 -2 -1 0 1 2 3 4 5 Fac o 2: 26,58% 25 Figu e 1b 1, 4 3 8,10 15 18 19 13,17,20,40 22 23 28 31 32 35 37 39 41 42 43 46 -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 Fac o 1 : 73,42% -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 Fac o 2 : 26,58% 36 27,29,30,33,34,47 2,5,6,9,11,12,14,21,26 16 45 24 45 7 38 25