Variability of Phenolic and Volatile Compounds in Virgin Olive Oil from Leccino and Istarska Bjelica Cultivars in Relation to Their Fruit Mixtures

Transcription

1 216 O. KOPRIVNJAK et l.: Phenolis nd Voltiles in Istrin Virgin Olive Oil, Food Tehnol. Biotehnol. 50 (2) (2012) ISSN (FTB-2867) sientifi note Vriility of Phenoli nd Voltile Compounds in Virgin Olive Oil from Leino nd Istrsk Bjeli Cultivrs in Reltion to Their Fruit Mixtures Oliver Koprivnjk 1 *, Vlerij Mjeti} 1, Krolin Brki} Buol 2 nd Ur{k Kosi} 3 1 Deprtment of Food Tehnology nd Control, Shool of Mediine, University of Rijek, Br}e Brnhett 20, HR Rijek, Croti 2 Institute of Agriulture nd Tourism, K. Hugues 8, HR Pore~, Croti 3 Deprtment of Agriulture, Polytehni of Rijek, K. Hugues 6, HR Pore~, Croti Reeived: June 30, 2011 Aepted: Novemer 25, 2011 Summry Phenoli nd voltile ompounds re losely relted to vlule gstronomi nd nutritionl properties, s well s oxidtive stility of virgin olive oil. Sine iohemil synthesis nd trnsformtion of these ompounds during olive proessing depend on the tivity of endogenous enzymes, whih re prtilly influened y geneti ftors, mixtures of different ultivrs ould hve either synergisti or ntgonisti effet on phenoli nd voltile ompounds in the resulting oil. In this ontext, two speifi ultivrs from the Istrin peninsul, Leino (L) nd Istrsk jeli (B), were seleted. Two monovrietl fruit smples (L100 nd B100) nd four mixtures in the following mss rtios: L/B=80:20, L/B=60:40, L/B=40:60 nd L/B=20:80 were prepred. The mss frtion of totl phenols ws determined olourimetrilly, while C6 nd C5 voltiles from lipoxygense pthwy were determined y hedspe solid-phse miroextrtion-gs hromtogrphy. Mss frtion of totl phenols in the oil smples from fruit mixtures hnged linerly from (199.5±7.2) in Leino to (642.0±61.7) mg/kg in Istrsk jeli, in strit orreltion with fruit mss rtio of the two ultivrs. Leino monovrietl smples hd sttistilly higher vlues (p 0.05) of C6 ldehydes ((15.32±1.69) vs. (10.91±0.62) mg/kg) nd C6 lohols ((2.96±0.98) vs. (0.17± 0.05) mg/kg), ut lower vlues of C5 ompounds ((0.77±0.12) vs. (0.96±0.05) mg/kg) ompred to Istrsk jeli smples. Voltiles hving diret ontriution to the oil rom (odour tivity vlue >1.0) were 1-penten-3-one (84 201), E-2-hexenl (26 42), hexnl ( ) nd Z-2-penten-1-ol ( ). A signifint synergisti effet ws oserved for C6 ldehydes in the se of L/B=40:60 fruit mixture. The ddition of Istrsk jeli to Leino fruits used signifint ntgonisti effet on C6 lohols, ut no signifint devitions from the expeted vlues were found in the se of C6 esters nd C5 ompounds. Results suggest tht fruit omintions of two hosen ultivrs in olive proessing offer interesting possiilities for trgeted modultion of phenoli nd voltile ompounds in virgin olive oil, nd onsequently, their sensory nd nutritionl hrteristis. Key words: voltiles, phenols, olive oil, Istrsk jeli, Leino, fruit mixtures Introdution Minor omponents, i.e. phenoli nd voltile ompounds, re losely relted to vlule gstronomi nd nutritionl properties, s well s to oxidtive stility of virgin olive oil (1). Ftors influening its iohemil synthesis nd trnsformtion during olive proessing hve *Corresponding uthor; Phone: ; E-mil: koliver@medri.hr

2 O. KOPRIVNJAK et l.: Phenolis nd Voltiles in Istrin Virgin Olive Oil, Food Tehnol. Biotehnol. 50 (2) (2012) 217 een studied from mny spets in reent yers. Ativity of endogenous enzymes, whih strts with rushing of fruits nd ontinues during olive pste kneding (2), depends on the degree of tissue frgmenttion, therml energy relesed due to frition (3,4), oxygen vilility nd durtion of single opertion (5). Regrding phenoli frtion, its ontent nd omposition in virgin olive oil is relted to -gluosidse (whih trnsforms hydrophili phenoli glyosides into less hydrophili glyones) nd esterse (whih releses simple phenols from omplex forms) (6), s well s to oxidtive enzymes (polyphenol oxidse, peroxidse nd lipoxygense), whih use oxidtive degrdtion of phenols (7). Generlly, higher temperture nd frgmenttion degree hieved y rushing ontriute to higher soluility of phenoli ompounds in the oil phse of olive pste. Higher kneding time ommonly leds to derese of phenoli sustnes in oil, euse of higher exposure to oxygen nd tivity of oxidtive enzymes (8). The iosynthesis of the min voltile ompounds of virgin olive oil strts t the moment of ell disruption during fruit rushing, when series of enzymes involved in lipoxygense (LOX) pthwy re relesed. The first sustrtes re phospholipids nd glyerolipids in memrne strutures (9) from whih yl hydrolse dethes polyunsturted ftty ids. Linolei nd linoleni ids re then oxidised y lipoxygense nd leved y hydroperoxide lyse into C6 ldehydes, whih n e lter redued to C6 lohols y lohol dehydrogense nd trnsformed to C6 esters y lohol yltrnsferse. It ws generlly ssumed tht milder rushing onditions (i.e. lower inrese of olive pste temperture) hve positive impt on the ontent of LOX voltiles in virgin olive oil (2-4). Voltiles re mostly produed t rushing, while during mlxtion, their iosynthesis is slowed down nd leds to higher vlues of C6 lohols s well s C6 nd C5 ronyl ompounds (2). However, longer mlxtion time hs positive impt on voltile onentrtion in oil sine it llows reprtition of ompounds etween oil nd wter phses in olive pste (10). Lower temperture nd suffiient oxygen vilility during this opertion re other prmeters tht ontriute to higher onentrtion nd more desirle omposition of voltile ompounds (11). Besides proessing ftors, the tivity of enzymes involved in the iosynthesis of phenolis nd LOX voltiles is in gret mesure relted to ripeness degree of helthy fruits nd their geneti hrteristis. It is well known tht virgin olive oil otined from different ultivrs, ultivted under identil onditions, hrvested t roughly equl ripeness degree, nd proessed in the sme mnner is hrterised y more or less different omposition nd onentrtion of minor omponents (2,12). Fruits of eh single ultivr proly ring their own speifi enzymti pkge, hrterised y prtiulr tivity, sensiility or quntity of single enzyme. Besides, differenes mong ultivrs in flesh/stone mss rtio, oil nd wter ontent or phenol nd id onentrtion ontriute to the diversity of environment (i.e. olive pste) in whih enzymes operte. Therefore, omintion of fruits of different ultivrs in olive proessing ould hve either synergisti or ntgonisti effet on the synthesis nd umultion of minor ompounds in the resulting oil. In ft, Angeros nd Bsti (13) hve shown tht the voltile profile hnges from qulittive nd quntittive point of view when fruits of ultivr Cortin re omined with those of Frntoio or Koroneiki. On the other hnd, when monovrietl oil smples re omined, the voltile profile n e esily predited, sine it is proportionl to the mss rtio of the omponents in oil mixtures. The im of this reserh is to evlute the effet of fruit omintions of two speifi ultivrs from the Istrin peninsul during olive proessing on minor ompounds in oil. Istrsk jeli (synonyms Istrsk eli or Binher istrin) is n utohthonous ultivr hrterised y lte ripening nd reltively high oil mss frtion in the fresh fruit (on verge 21 %). Among ultivrs introdued to Istri, Tusn ultivr Leino is the most widespred nd, in the given pedolimti onditions, it ripens erly nd umultes muh lower oil mss frtion in fresh fruit (on verge 12 %) ompred to Istrsk jeli (14-16). In the lol produing prtie, oth ultivrs re hrvested ontemporneously nd often proessed s fruit mixture, regrdless of their different stges of ripeness. Mterils nd Methods Olive fruits nd preprtion of virgin olive oil smples Olive fruits of two ultivrs, Leino (L) nd Istrsk jeli (B), grown in the region of Istri (Croti), were hndpiked in the middle of Otoer Mturity index (MI) of the fruits of eh ultivr ws determined pplying the method desried y Gutiérrez et l. (17), whih is sed on the evlution of olive skin nd pulp olour. Smples of fruit mixtures of two ultivrs were prepred y omining fresh nd helthy fruits in the following mss rtios: L/B=80:20, L/B=60:40, L/B=40:60 nd L/B=20:80. The prepred mixtures of olive fruits, s well s two monovrietl fruit smples (L100 nd B100), were proessed in the lortory within 24 h fter the hrvesting. The lortory plnt for oil extrtion onsisted of the hmmer rusher, vertil olive pste mixers pled in the thermostted wter th nd entrifuge (MC2 Ingenieri y Sistems, Seville, Spin). Olive pste smples of eh omintion of vrieties were divided into three portions of 600 g, whih were mlxed t (26± 0.5) C for 40, 50 nd 60 min, respetively. Tking into ount vritions in mlxtion durtion in ommon prodution prtie, the three portions were onsidered s independent repetitions of single vriety omintion. After entrifugtion t 3600 rpm for 70 s, the extrted oil ws filtered through the filter pper nd stored t room temperture in fully filled nd seled drk ottles until nlyses. Regents nd nlytil mterils Cffei id (purity 99 %) nd methnol were purhsed from Pnre (Brelon, Spin), while sodium ronte dehydrte nd Folin-Ciolteu regent were otined from Merk KGA (Drmstdt, Germny). Twelve stndrds of voltile ompounds hd GC purity 95 %. E-2-hexenl, E-2-pentenl, pentn-3-one nd Z-2-penten-

3 218 O. KOPRIVNJAK et l.: Phenolis nd Voltiles in Istrin Virgin Olive Oil, Food Tehnol. Biotehnol. 50 (2) (2012) -1-ol were purhsed from Sigm-Aldrih (Steinheim, Germny). Hexn-1-ol, 1-penten-3-one, E-2-hexen-1-ol, E-3-hexen-1-ol, hexnl, hexyl ette, Z-3-hexenyl ette nd Z-3-hexen-1-ol were supplied from Fluk (Sigm- -Aldrih, Buhs, Germny). Determintion of totl phenols mss frtion A mss of 2 g of oil smples ws pled in 20-mL srew p test-tue nd extrted twie with 5 ml of methnol/wter (80:20, y volume). Eh time the mixture ws stirred for 5 min in vortex pprtus (IKA, Stufen, Germny) nd entrifuged t 3800 rpm for 4 min. Upper methnol lyers were trnsferred into 25-mL volumetri flsk, whih ws then filled up with methnol/wter (80:20, y volume). The determintion of totl phenoli ontent in the extrts ws sed on the proedure introdued y Gutfinger (18) using Folin-Ciolteu regent nd ffei id s stndrd. The nlyses were run in triplite. Anlysis of voltile ompounds A fused sili fire oted with highly rosslinked divinylenzene/roxen/polydimethylsiloxne (DVB/ CAR/PDMS), 1 m length, 50/30 mm film thikness (Supelo, Bellefonte, PA, USA), ws used for the hedspe solid-phse miroextrtion (HS-SPME) nd onentrtion of voltiles. The smple (4.0 g) ws pled in 10-mL vil ontining mirostirring r nd seled with PTFE/ silione septum (Restek, Bellefonte, PA, USA). Before extrtion, the hedspe in the vil ws stilized y equilirtion t 40 C for 10 min nd gentle gittion for 3 min with mgneti stirrer. The extrtion ws rried out t 40 C for 40 min. The therml desorption of the nlytes ws hieved y inserting the fire into the injetion port of the GC system equipped with n SPME liner (0.80 mm i.d.) in splitless mode for 3 min t 245 C. Before smpling, the fire ws reonditioned for 10 min in n injeting port t 245 C nd lnk runs were done periodilly during the study. Gs hromtogrphy (GC) nlyses were performed using Vrin 3350 gs hromtogrph (Vrin In., Hrour City, TA, USA) equipped with flme ioniztion detetor (FID) operted t 248 C nd pillry olumn Rtx-WAX (30 m 0.25 mm i.d mm film thikness; Restek). Initil oven temperture ws 40 C, inresed fter 8 min to 85 C t 2.5 C/min nd finlly inresed to 245 C t 10 C/min nd kept for 20 min. The rrier gs ws helium t pressure of 15 psi (10.3 kp) t the olumn hed. Voltiles were identified y ompring their retention times to those of the pure stndrds. Quntifition ws rried out using lirtion urves of pure stndrds dissolved in freshly refined sunflower oil. The nlyses were run in triplite. Sttistil nlysis Differenes mong smples were tested y one-wy nlysis of vrine t 5 % signifine level. The homogeneity of vrine ws tested y the Brown-Forsythe test. The men vlues were ompred using the Tukey s honestly signifint differene test (p 0.05). Sttistil nlyses were performed using the softwre pkge STA- TISTICA v. 9 (19). Results nd Disussion In ordne with the ville literture, the oil smples otined from the two seleted ultivrs differ gretly in totl phenoli ontent, whih is on verge two to four times higher in the oil from Istrsk jeli (14,20-22). This ws lso onfirmed in this study, sine monovrietl oil otined from Istrsk jeli fruits hd out three times higher vlues ((642.0±61.7) mg/kg) thn the oil from Leino fruits ((199.5±7.2) mg/kg) (Fig. 1). Certinly, esides geneti ftors, the oserved differenes re lso relted to different fruit ripening stges of the two ultivrs t the moment of proessing. Nmely, Leino nd Istrsk jeli hve different dynmis of fruit ripening. Fresh olive fruits of Istrsk jeli used in this reserh hd lower mturity index (0.7 most of the fruits hd yellowish green epidermis), ompred to those of Leino (2.8 most of the fruits hd light violet epidermis). w(totl phenols)/(mg/kg) Fig. 1. Totl phenols in the oil smples otined from fruit mixtures of Leino (L) nd Istrsk jeli (B). Numers next to the letter L or B represent the mss rtio of Leino or Istrsk jeli fruits in fruit mixtures, respetively. Results re expressed s men vlues of nine mesurements (3 independent repetitions triplite nlyses)±s.d.; the men vlues lelled with different letters re signifintly different (Tukey s test, p<0.05) Nevertheless, in lol prodution prtie, oth ultivrs re often hrvested ontemporneously nd proessed s fruit mixtures, regrdless of their different stges of ripeness. The totl phenoli ontent in the oil otined from fruit mixtures hnged linerly in strit orreltion with the fruit mss rtio of the two ultivrs. This suggests tht no synergisti or ntgonisti effets on the enzymti tivity were indued omining the fruits of these two ultivrs with presumly different enzymti ptterns, wter nd oil ontent. Consequently, totl phenoli mss frtion should e esily predited in the oil otined y proessing fruit mixtures of Leino nd Istrsk jeli. Contrry to the totl phenoli ontent, Leino monovrietl oil ws riher in voltile omponents derived from lipoxygense pthwy ((19.15±2.18) mg/kg) thn Istrsk jeli ((12.18±0.70) mg/kg) (Tle 1). Hexnl nd E-2-hexenl re the min C6 ldehydes tht re produed t the initil prt of this enzymti pthwy. Leino monovrietl oil smples hd signifintly higher d e e

4 O. KOPRIVNJAK et l.: Phenolis nd Voltiles in Istrin Virgin Olive Oil, Food Tehnol. Biotehnol. 50 (2) (2012) 219 Tle 1. Mss frtion of voltile ompounds from LOX pthwy in oil smples otined from fruit mixtures of Leino (L) nd Istrsk jeli (B) w/(mg/kg) Voltile ompounds hexnl (0.17±0.03) (0.15±0.01) (0.17±0.03) (0.19±0.01) (0.18±0.01) (0.18±0.02) E-2-hexenl (15.15±1.60) (14.95±0.63) (15.88±2.03) (17.55±1.02) (16.51±0.91) (10.73±0.61)d SC6 ldehydes (15.32±1.69) (15.09±0.63) (16.06±2.06) (17.73±1.03) (16.69±0.92) (10.91±0.62)d hexn-1-ol (0.20±0.06) (0.05±0.00) (0.05±0.01) (0.04±0.00) (0.03±0.01) (0.01±0.00)d Z-3-hexen-1-ol (0.37±0.25) (0.41±0.10) (0.39±0.19) (0.07±0.01) (0.08±0.01) (0.11±0.02) E-3-hexen-1-ol tr. 0.09±0.01 n.d. n.d. n.d. n.d. E-2-hexen-1-ol (2.38±0.72) (1.40±0.11) (0.08±0.02) (0.08±0.02) (0.06±0.01) (0.05±0.03) SC6 lohols (2.96±0.98) (1.94±0.14) (0.52±0.21) (0.19±0.03) (0.17±0.02) (0.17±0.05) hexyl ette tr. tr. n.d. n.d. n.d. n.d. Z-3-hexenyl ette (0.14±0.04) (0.16±0.02) (0.13±0.02) (0.16±0.01) (0.14±0.01) (0.14±0.03) SC6 esters (0.14±0.04) (0.18±0.02) (0.13±0.02) (0.16±0.01) (0.14±0.01) (0.14±0.03) 1-penten-3-one (0.09±0.02) (0.06±0.01) (0.11±0.02) (0.11±0.02) (0.11±0.01) (0.14±0.01) E-2-pentenl (0.10±0.01) (0.03±0.01) (0.09±0.01) (0.11±0.01) (0.11±0.01) (0.08±0.00)d Z-2-penten-1-ol (0.33±0.08) (0.47±0.03) (0.40±0.05) (0.51±0.03) (0.53±0.03) (0.65±0.05)d pentn-3-one (0.25±0.07) (0.08±0.01) (0.06±0.02) (0.08±0.02) (0.07±0.02) (0.09±0.01) SC5 ompounds (0.77±0.12) (0.63±0.03) (0.66±0.09) (0.81±0.05) (0.82±0.07) (0.96±0.05) totl voltiles (19.15±2.18) (17.85±0.74) (17.37±2.36) (18.51±1.08) (17.83±0.99) (12.18±0.70) Results re men vlues of nine mesurements (3 independent repetitions triplite nlyses)±s.d.; the men vlues within eh row lelled with different letters re signifintly different (Tukey s test, p<0.05); tr.=tres; n.d.=not deteted Numers next to the letter L or B represent the mss rtio of Leino or Istrsk jeli fruits in fruit mixtures, respetively vlues of the two C6 ldehydes ompred to Istrsk jeli monovrietl oil smples, nd this ws onsistent with the previously pulished dt for these ultivrs (23), lthough it must e stressed tht differenes in their fruit ripening stge t the moment of proessing should not e negleted. Different vlues of C6 ldehydes ould e due to different yl hydrolse tivity nd onsequently good or poor vilility of free polyunsturted ftty ids, s it ws found y Sánhez-Ortiz et l. (24) for ultivrs Piul nd Arequin, respetively. Nevertheless, y inresing the mss frtion of Istrsk jeli fruits in the mixtures with Leino, no redution of C6 ldehydes ws oserved. Moreover, slight inrese regrding Leino monovrietl oil ould e seen in smples with 40 % (L60) nd 80 % (L20) of Istrsk jeli fruits, whih eme sttistilly signifint in the se of 60 % (L40). The mss frtion of C6 lohol representtives, whih re produts of tlyti tion of lohol dehydrogense on C6 ldehydes, ws lso signifintly higher in Leino monovrietl oil smples, ut its trend ws opposite to tht of C6 ldehydes. The ddition of 60 nd 80 % of Istrsk jeli to Leino fruits used ler derese of C6 lohols, yielding vlues similr to Istrsk jeli monovrietl oil smples. In spite of pprently higher sustrte vilility (higher mss frtion of C6 ldehydes), the presene of Istrsk jeli in Leino olive pste gve rise to ntgonisti effet on C6 lohol iosynthesis (vlues were lower thn expeted on the sis of the ultivr fruit mss rtio). In ft, the ove disussed inrese of C6 ldehyde mss frtion ould e the onsequene of their umultion used y the repression of C6 lohol iosynthesis, rther thn enhned prodution. Similr synergisti phenomen in the se of C6 ldehydes, or ntgonisti in the se of lohols hexn-1-ol nd E-2-hexen-1-ol, hve een reported for fruit mixtures of Cortin nd Koroneiki, or Cortin nd Frntoio y Angeros nd Bsti (13). The reson for repressed C6 lohol iosynthesis ould e high mss frtion of phenoli ompounds in Istrsk jeli fruits, nd sensiility of lohol dehydrogense to their inhiitory tion, sine it is known tht phenols re le to ind nd inhiit vrious enzymes (25). Regrding the representtives of C6 esters, monovrietl oil smples of two ultivrs ontined similr vlues. The inrese of Istrsk jeli mss frtion in Leino olive pste did not use signifint hnges, exept in the se of 20 % ddition (L80). This ould men tht lohol etyl trnsferse from Istrsk jeli ws more tive, resulting in higher prodution when sustrtes (C6 lohols) were ville in undne, suh s in the se of L80 smples. As for representtives of C5 voltiles, produts of n dditionl rnh of the LOX pthwy (2), signifintly higher vlues n e oserved in Istrsk jeli monovrietl oil smples. By inresing the mss frtion of Leino in the mixtures with Istrsk jeli fruits, the mss frtion of C5 ompounds in the resulting oil smples deresed. In the se of 60 nd 80 % of Leino, C5 ompounds were even lower thn in the oil smples produed from 100 % Leino fruits. Nevertheless, when onsidering the literture on odour thresholds of single voltile ompounds (12,26), only four out of twelve nlysed omponents hd odour tivity vlues () higher thn 1.0, mking diret on-

5 220 O. KOPRIVNJAK et l.: Phenolis nd Voltiles in Istrin Virgin Olive Oil, Food Tehnol. Biotehnol. 50 (2) (2012) penten-3-one E-2-hexenl hexnl Z-2-penten-1-ol Fig. 2. Odour tivity vlue () of ompounds with diret ontriution to the oil rom in the oil smples otined from fruit mixtures of Leino (L) nd Istrsk jeli (B). Numers next to the letter L or B represent the mss rtio of Leino or Istrsk jeli fruits in fruit mixtures, respetively. Results re expressed s men vlues of nine mesurements (3 independent repetitions triplite nlyses)±s.d.; the men vlues lelled with different letters re signifintly different (Tukey s test, p<0.05). Dshed lines represent liner trend etween the vlues of monovrietl oil smples, lulted on the sis of fruit mss rtio. Literture threshold vlues (26): 0.42 mg/kg (E-2-hexenl), mg/kg (1-penten-3-one), 0.08 mg/kg (hexnl), 0.40 mg/kg (Z-2-penten-1-ol) d triution to the plesnt rom of oil smples. The odour tivity vlues of 1-penten-3-one, E-2-hexenl, hexnl nd Z-2-penten-1-ol, in reltion to the vrietl omposition of fruit mixtures, re shown in Fig. 2. The highest ontriution to the rom of oil smples from oth ultivrs nd their fruit mixtures ws mde y 1-penten-3-one, whose rnged from 84 (L80) to round 201 (B100). This omponent is hrterised y speifi odour desriptors (pungent, mustrd) onsidered positive for virgin olive oil rom (12). Despite the highest odour tivity vlues of monovrietl Istrsk jeli oil (=201), no positive influene on Leino smples ws oserved y inresing the mss frtion of Istrsk jeli fruits. The seond most influening ompound ws E-2-hexenl (odour desriptors: itter lmond, green-fruity (12)), with rnging from 26 (B100) to round 40 (L20 nd L40). The inrese of odour tivity vlue to the level of out 50 % in the smples with 20 nd 40 % of Leino fruits should hve n evident impt on stronger pereption of green-fruity nd lmond odour notes regrding monovrietl Istrsk jeli oil. Hexnl (odour desriptors: green pple, grssy (12)) showed negligile vritions of odour tivity vlues (from 2.0 to 2.5) in reltion to the fruit mixture omposition. The ompound with the most liner trend of odour tivity vlues in the rnge from 1.3 (monovrietl Leino oil) to 2.6 (monovrietl Istrsk jeli oil) ws Z-2-penten-1-ol (odour desriptors: grssy, nn (12)). Consequently, ler positive ontriution of Istrsk jeli to the pereption of grssy nd nn odour notes in the oil otined from the mixtures with Leino fruits should e expeted. Conlusions On the sis of the otined results, it ould e onluded tht fruit omintions of the two hosen ultivrs offer interesting possiilities for trgeted modultion of minor ompounds of virgin olive oil nd, onsequently, their sensory hrteristis. While hnges of the mss frtion of phenoli ompounds ould e mnged simply, the voltile profile requires further reserh tking into ount other hrteristis of fruits, suh s the ripening index, flesh/stone mss rtio or oil nd wter mss frtion. Aknowledgement The presented results re derived from the sientifi projets Biotive nd voltile ompounds of VOO in proessing nd finishing ( ) nd Chrteriztion of utohthonous olive vrieties in Istri ( ) supported y the Ministry of Siene, Edution nd Sports of the Repuli of Croti. Referenes 1. M. Servili, R. Selvggini, S. Esposto, A. Ttihi, G. Montedoro, G. Morozzi, Helth nd sensory properties of virgin olive oil hydrophili phenols: Agronomi nd tehnologil spets of prodution tht ffet their ourrene in the oil, J. Chromtogr. A, 1054 (2004) F. Angeros, M. Servili, R. Selvggini, A. Ttihi, S. Esposto, G. Montedoro, Voltile ompounds in virgin olive oil: Ourrene nd their reltionship with the qulity, J. Chromtogr. A, 1054 (2004)

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