SPRAY-DRIED OF SICILIAN NERO D'AVOLA WINES, EVALUATION OF THE AROMATIC AND PHENOLIC PROFILES BY MASS SPECTROMETRIC TECHNIQUES

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1 SPRAY-DRIED OF SICILIAN NERO D'AVOLA WINES, EVALUATION OF THE AROMATIC AND PHENOLIC PROFILES BY MASS SPECTROMETRIC TECHNIQUES Giuseppe Avellone a, Andrea Salvo b,c, Rosaria Costa b,c, Emanuele Saija b,c, David Bongiorno a, Vita Di Stefano a, Giorgio Calabrese d, Giacomo Dugo a b. a Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF), Università di Palermo, Viale delle Scienze, Parco d Orleans II, 9128 Palermo, Italy b Dipartimento di Scienze Biomediche, Odontoiatriche, e delleimmagini Morfologichee Funzionali(Biomorf), University of Messina, Viale Annunziata, Messina, Italy c Science4Life s.r.l., a spin-off of the University of Messina, Messina, Italy d Dipartimento di Scienze Agrariee Forestali, Universita' degli Studidi Torino, Via Verdi 8, 1124 Torino, Italy

2 INTRODUCTION Spray-drying falls within the group of microencapsulation technologies, including spray-chilling, fluidized-bed coating, extruding, lyophilisation, coacervation, among others(desai& Park, 25; Nedovic et al., 211). It finds wide application in food industry since decades, basically due to its cheapness, flexibility, robustness, efficiency. Based on a simple definition, encapsulation is a technique which entraps particles (usually bioactive compounds) within a wall material, working as a shell or matrix. The products of such a technological process are microcapsules with diameters comprised in the range of mm mm, generally containing active ingredients. More specifically, spray-drying is a technological process where a liquid is atomized through a hot gas (air or nitrogen) current, becoming consequently a powder(gharsallaoui et al., 27).

3 INTRODUCTION Mainly because of the water removal from food commodities, numerous are the advantages derived from spray-drying: i) reduction of microbiological decay events; ii) instantaneous solubilisation of spray-dried products (improved product s handling); iii) decrease of transport costs due to consistent volume reduction of powdered products( green feature of the technology); iv) protection of the core material against environmental factors (i.e. moisture, light, oxygen); v) improvement of organoleptic properties of a food (e.g. masking bitterness of an ingredient by coating it with a wall material having a pleasant taste); vi) elimination of cross reactions between more ingredients.

4 INTRODUCTION A key role in a successful spray-drying procedure is played by the wall material chosen as encapsulating agent; the latter must be able to protect the capsule content, to be stable over time and to avoid interaction with the outer environment. Encapsulation technologies are utilized not only in food industry, but also in other fields(e.g. dried detergents reconstituted upon use). A variety of synthetic polymers is available as wall material; however, this list is definitely restricted when the spray-dried product is destined to food consumption. Commonly, carbohydrates (starches, syrup solids, maltodextrins, pectins), gums (gum Arabic, mesquite gum) or milk proteins are employed as wall material(gharsallaoui et al., 27).

5 AIM Nero d Avola wines produced in Sicily(Italy) were investigated in order to: i) elucidate the aromatic composition by means of HS-SPME coupled with SPME-GC/MS; ii) assess the polyphenolic content by UHPLC tandem mass spectrometry; iii) compare the results obtained from both the screenings with those relative to the same wines, but preliminarily subjected to spray-drying processing. The purpose was basically to determine if and how microencapsulation affects the quality of Nero d Avola wine as concerns its volatile composition and phenolic profile.

6 SAMPLES AND METHODS Commercial Nero d Avola wines (geographical indication) were from the brand Conte di Matarocco, Terre Siciliane and produced by Cantine Paolini(Sicily, Italy). Spray-drying condition For spray-drying procedures, a Mini Spray Dryer B-29 (Büchi, Cornaredo, Italy), was exploited. A 2 ml aliquot of wine (12% v/v ethanol) was added with 4 g of maltodextrin * in a screw capped conical flask, and homogenized for 15 min ca, at room temperature (19-2 C) until complete dissolution. Inlet and outlet temperatures(nitrogen) were 15 and 65 C, respectively; Feed flow rate was set at 18% of the maximum tolerated by the instrument. Drying rate was approximatelyof5mlofwineper1min. Theyieldwasestimatedas82%w/vca. * Maltodextrin (dextrose equivalent )

7 Solid-Phase Microextraction For SPME extraction, four different fiber coatings were used: divinylbenzene/carboxen/polydimethylsiloxane(dvb/car/pdms,5/3um), carbowax/divinylbenzene(cw/dvb, 7 um), carboxen/polydimethylsiloxane(car/pdms, 85 um), polydimethylsiloxane(pdms, um). In order to assess the best extraction time for each fiber several preliminary tests at increasing times(5, 1, 15 and 2 min) were evaluated, it was determined that 15 min was suitable to obtain equilibrium and to reproduce the extraction procedure. 4 ml of wine, whether untreated or re-solubilized, were added with.6 g of NaCland 1 ul of a 2 ppm solution of internal standard (1-hexan-d13-ol) and placed in a 8 ml amber glass. Spray-dried wines were re-solubilized by dissolving 2 g of powdered wine in 1 ml of an ethanol/water (12:88, v/v) solution. Wine samples were pre-conditioned at 35 C for 3 min and under agitation (25 rpm); successively

8 GC-MS A Focus GC- DSQ II gas chromatograph/mass spectrometer (Thermo, CA, USA) equipped with a 3 m.25 mm i.d..25 um film thickness ZB-WAX column (Phenomenex, CA, USA) was used. The oven temperature programme was from 4 C(3 min) at 1 C/min to 25 C, hold 2 min. Gas flow rate (He) was.8 ml/min. Injection took place in splitless mode(3min)andatatemperatureof25 C. Data were acquired in the electron impact (EI) mode with an ionisation voltage of7ev,usingfullscanionmonitoring foramassrange35-4m/z. Component assignment was based on computer matching with the WILEY 7 and NIST 2 mass spectral libraries; and on comparison with data retrieved from literature The relative amounts of volatiles (semiquantitative analysis) were obtained by multiplying the area ratio of target compound/internal standard by the concentration(ug/l) of the internal standard.

9 HS-SPME-GC/MS (TIC) fingerprints of untreated wine samples extracted by means of four different fiber coatings RT: Relative Abundance Time (min) NL: 1.6E9 TIC MS vino_pdms_ um NL: 1.72E9 TIC MS Vino_DVB- CAR- PDMS_5-3um_ NL: 1.77E9 TIC MS vino_carxe N- PDMS_85um NL: 1.48E9 TIC MS vino_carwa X-DVB_7um

10 HS-SPME-GC/MS (TIC) chromatograms of spray-dried wines after resolubilization, extracted by different fibers RT: NL: 1.11E9 TIC MS vinoliofilizzato_1 2%EtOH_PDMS _um Relative Abundance Time (min) NL: 9.93E8 TIC MS vinoliofilizzato_1 2%EtOH_DVB- CAR-PDMS_5-3um NL: 1.2E9 TIC MS vinoliofilizzato_1 2%EtOH_CAR WAX- DVB_7um NL: 1.25E9 TIC MS vinoliofilizzato_1 2%EtOH_CARB OXEN- PDMS_85um

11 HS-SPME-GC-MS COMPOSITION OF WINE SAMPLES 1/4 DVB/Car/PDMS CW/DVB Car/PDMS PDMS Nr. Compound Odour threshold* (mg/l) Neat wine (mg/l) Spray-dried wine (mg/l) Neat wine (mg/l) Spray-dried wine (mg/l) Neat wine (mg/l) Spray-dried wine (mg/l) Neat wine (mg/l) Spray-dried wine (mg/l) 1 Acetaldehyde Dimethyl sulfide 1.2 n.f. n.f. n.f..12 n.f. n.f. n.f. 3 Ethyl formate N/A.24.2 n.f. n.f Ethyl acetate 7, Ethanol, Ethyl propanoate n.f. n.f. n.f..28 n.f..677 n.f. 7 Ethyl isobutyrate n.f..381 n.f..453 n.f n.f. 8 2,3-Butanedione Ethyl butyrate 1,6.877 n.f..314 n.f..49 n.f n.f. 1 1-Propanol 5, Succinic acid, butyl propyl ester N/A.45 n.f. n.f. n.f..37 n.f. n.f. n.f. 12 Ethyl 2-methylbutyrate n.f..126 n.f..233 n.f..881 n.f. 13 Ethyl isovalerate n.f n.f Methylbutyl acetate 5 n.f..2 n.f. n.f. n.f..24 n.f. n.f. 15 Isobutanol 4, ,2,6-Trimethyl-6-vinyltetrahydropyran N/A.9 n.f. n.f. n.f..41 n.f. n.f. n.f. 17 Isoamyl acetate Ethyl valerate n.f..171 n.f Butanol 15,.61 n.f. n.f. n.f..73 n.f..167 n.f. 2 Sulfur dioxide N/A n.f. n.f n.f. n.f. n.f. n.f. 21 Limonene 2 n.f..69 n.d..94 n.f. n.f Isoamyl alcohol 3, Ethyl hexanoate ,4-Hexadienoic acid, ethyl ester (2E,4E)- N/A n.f..12 n.f..57 n.f. n.f. n.f. n.f. Compounds in bold are odour active Values are means of triplicate analyses. n.f. = not found. N/A = not available. *Values retrieved from references Tao & Zhang, 21; Verzera et al., 216; L.J. van Gemert, 211.

12 HS-SPME-GC-MS COMPOSITION OF WINE SAMPLES 2/4 25 (1E,2E)-Dipropenylcyclobutane N/A n.f. n.f. n.f. n.f..2 n.f. n.f. n.f. 26 Isoamyl butyrate N/A n.f. n.f. n.f. n.f. n.f. n.f..65 n.f. 27 Hexyl acetate 1,5.49 n.f..12 n.f. n.f. n.f..73 n.f. 28 Octanal.7 n.f n.f Acetoin 8.56 n.f n.f. n.f. n.f. 3 3-Hexenoic acid, ethyl ester N/A.29 n.f..8 n.f. n.f. n.f..53 n.f Methyl-1-pentanol 5,.12 n.f..49 n.f..16 n.f..29 n.f Heptanol 3 n.f. n.f..12 n.f..16 n.f. n.f. n.f Methyl-1-pentanol n.f..73 n.f..45 n.f..86 n.f. 34 Ethyl heptanoate n.f..24 n.f..12 n.f..151 n.f. 35 Ethyl lactate 14, Hexanol 8, (3E)-Hexen-1-ol 4 n.f. n.f..37 n.f. n.f n.f. 38 (3Z)-Hexen-1-ol 4 n.f. n.f..151 n.f. n.f. n.f..98 n.f. 39 Methyl octanoate n.f..29 n.f..131 n.f. 4 Nonanal n.f Carbon disulfide N/A.24 n.f. n.f. n.f..16 n.f. n.f. n.f. 42 Ethyl octanoate Octen-3-ol 1 n.f. n.f..24 n.f. n.f. n.f. n.f. n.f Heptanol n.f Isoamyl hexanoate N/A n.f. n.f..16 n.f. n.f. n.f. n.f. n.f. 46 Furfural 14, n.f. 47 Acetic acid N/A n.f. n.f n.f. n.f Propyl-1-pentanol N/A Ethyl-4-methylpentanol N/A.11 n.f..118 n.f..82 n.f..18 n.f. 5 Ethyl nonanoate N/A n.f..9 n.f. n.f. n.f. n.f..265 n.f. 51 2,3-Butanediol 12,.94 n.f n.f. 52 Linalool n.f. 53 n-octyl formate N/A n.f..294 n.f. Compounds in bold are odour active Values are means of triplicate analyses. n.f. = not found. N/A = not available. *Values retrieved from references Tao & Zhang, 21; Verzera et al., 216; L.J. van Gemert, 211.

13 HS-SPME-GC-MS COMPOSITION OF WINE SAMPLES 3/4 54 Isoamyl lactate n.f n.f. 55 b-ionone.9 n.f. n.f n.f. 56 Hexadecane N/A n.f..33 n.f. n.f n.f Propylene Glycol N/A.57 n.f n.f. n.f. n.f. n.f. 58 n-nonylcyclohexane N/A n.f..33 n.f..98 n.f. n.f. n.f Terpinen-4-ol 11 n.f. n.f. n.f. n.f. n.f..12 n.f. n.f. 6 Diethylene Glycol ethyl ether N/A n.f. n.f n.f. n.f. n.f. n.f Furancarboxylic acid, ethyl ester N/A n.f..86 n.f. 62 Ethyl decanoate Dihydro-2(3H)-furanone 5, Butanoic acid Furfuryl alcohol 2, n.f. n.f. n.f. n.f n.f. n.f. 66 Diethyl succinate 2, Ethyl dec-(9e)-enoate n.f. n.f. n.f. n.f. n.f. n.f..53 n.f Methylhexanoic acid N/A n.f n.f. 69 a-terpineol n.f Ethyl decanoate 2 n.f..12 n.f..49 n.f. n.f. n.f. n.f (Methylthio)-1-propanol 1, n.f. 72 Diethyl glutarate N/A.37 n.f n.f..53 n.f. 73 Methyl salicylate n.f. n.f..131 n.f. n.f. n.f. n.f. n.f. 74 Phenylethyl acetate n.f b-damascenone Ethyl dodecanoate 1,5 n.f..212 n.f n.f..8 n.f Hexanoic acid 2, Benzyl alcohol 2, Butanedioic acid, ethyl-3-methylbutyl ester N/A Phenethyl alcohol 14, Dodecanol 1, Diethylene glycol N/A n.f..41 Compounds in bold are odour active Values are means of triplicate analyses. n.f. = not found. N/A = not available. *Values retrieved from references Tao & Zhang, 21; Verzera et al., 216; L.J. van Gemert, 211.

14 HS-SPME-GC-MS COMPOSITION OF WINE SAMPLES 4/4 83 Ethyl tetradecanoate 2, n.f. n.f. n.f..783 n.f. n.f. n.f Octanoic acid Hexyl-2,5-dihydro-2,5-dioxo-3- N/A n.f. n.f furanacetic acid 86 Hexadecanal 4,5 n.f. n.f..24 n.f. n.f. n.f. n.f. n.f hexadecanol N/A n.f. n.f. n.f..437 n.f. n.f. n.f. n.f Ethylphenol 44 n.f. n.f. n.f. n.f..4 n.f. n.f. n.f. 89 Nonanoic acid 3, n.f. n.f. n.f. n.f Ethyl palmitate 1, n.f. n.f Decanoic acid 1,.78 n.f..94 n.f..8 n.f..269 n.f. 92 2,4-di-t-Butylphenol Dodecanoic acid 1, n.f. n.f. n.f. n.f. n.f. n.f Tetradecanoic acid 1, n.f. n.f. n.f. n.f. n.f. n.f. 95 Octadecanoic acid 2, n.f. n.f. n.f. n.f. n.f. n.f Octadecenoic acid N/A.29 n.f n.f TOTAL Compounds in bold are odour active Values are means of triplicate analyses. n.f. = not found. N/A = not available. *Values retrieved from references Tao & Zhang, 21; Verzera et al., 216; L.J. van Gemert, 211. Precision of SPME-GC-MS method was evaluated by measurement of RSD% relative to three replicates for each sample and preliminary tests to be analyzed: values obtainedwereintherange.5-7.6%,withanaveragersd%of3.4%.

15 DVB/Car/PDMS (neat wine),11%,14% 1,58%,59%,49%,74% aldehydes esters alcohols sulphur 46,15% 5,22% ketones other acids terpenoids,74% 1,97% 2,1% DVB/Car/PDMS (spray-dried wine),1% 1,% 3,94% aldehydes esters alcohols sulphur ketones other 51,97% 38,28% acids terpenoids

16 UHPLC-MS/MS The LC-MS-MS system was a UHPLC (Dionex UltiMate 3 Rapid Separation LC) system by Thermo Fischer Scientific equipped with an autosampler and controlled by Chromeleon 7.2 software, by Thermo Fisher (Bremen, DE) and Dionex Softron GmbH (Germering, DE). The UHPLC system was coupled to a quadrupole Orbitrap mass spectrometer (Q Exactive) (Thermo Scientific, Germany), equipped HESI ion source. The HESI conditions were: sheath gas flow rate 35 (arbitrary units); auxiliary gas unit flow rate 4 (arbitrary units); sweep gas flow rate 7 (arbitrary units); spray voltage 3,5kV; S lens RF level 3; capillary temperature 25 C; auxiliary gas heater temperature 25 C. The UHPLC column was a Phenomenex Luna C18 (2) 5x1mm, 2.5μm. The column temperature was set at 35 C and the injection volume at 1. µl. Mobile phase composition: formic acid/water.1% v/v (eluent A), acetonitrile (eluent B), at a flow rate of 5 μl min-1. The gradient was: 2 min, 5% B; min, linear increase to 1% B; min, linear increase to 25% B; min, linear increase to 95% B; 29 3 min, hold 95% B; 3 31 min, linear decrease5%b;31 33min,hold5%B. The MS was operated in electrospray negative mode and the analyses were conducted in two acquisitions modes: Full-Scan and SIM. The resolution power in full scan was 35. FWHM (at m/z 2) and the scan range was -8 m/z. Scan rate was 2 scan s-1 and the automatic gain control(agc) target was set at 1e 5 ions for a maximum injection time of 2 ms. The quadrupole s isolation windowwas1m/z.

17 PHENOLIC CONTENT A targeted qualitative screening of the polyphenolic fraction was carried out by means of LC-ESI( )-MS analysis. Measured masses of target analytes have been reported in table. Compound Measuredmass [M-H] - Formula MW Resveratrol C 14 H 12 O Myricetin C 15 H 1 O Catechin C 15 H 14 O 6 29 Gallic acid C 7 H 6 O 5 17 Ferulic acid C 1 H 1 O Caffeic acid C 9 H 8 O 4 18 Measured masses by using LC-ESI quadrupole Orbitrap mass spectrometer (negative ionization).

18 PHENOLIC CONTENT Comparison of the pholyphenolic profiles of untreated and spray-dried wines has been evidenced in figures. Selected ion monitoring allowed to achieve the determination of seven phenolic compounds in both the types of samples investigated. More specifically, three carboxylic acids (gallic, caffeic and ferulic acids), one stilbene (trans-resveratrol), two flavanols (catechin and epicatechin) and one flavonoid (myricetin), were detected. RT: SM: 3G gallic acid NL: 1.58E ms [ ] MS vino_1 Relative Abundance catechin caffeic acid ferulic acid myricetin resveratrol Time (min) epicatechin 31.1 NL: 1.7E ms [ ] MS vino_1 NL: 4.3E ms [ ] MS vino_1 NL: 7.71E ms [ ] MS vino_1 NL: 6.9E ms [ ] MS vino_1 NL: 1.97E ms [ ] MS vino_1 HPLC-ESI-MS (SIM) chromatograms of phenolics determined in samples of untreated wines.

19 PHENOLIC CONTENT This led to the assumption that the microencapsulation process didn t affect the qualitative composition of the polyphenolic fraction. Although only a rough screening was carried out in this study, by comparing the signal intensities of target analytes, it might be supposed that the amounts of phenolics are quite similar in both neat and spray-dried samples. All the polyphenols determined in this study were previously reported for Nero d Avola wines. Each standard was injected 5 times consecutively, at one concentration level (namely 1 ppm) and repeatability assessed through RSD% (on average 2.5%). RT: SM: 3G Relative Abundance catechin caffeic acid ferulic acid 12.4 myricetin resveratrol gallic acid Time (min) epicatechin NL: 9.75E ms [ ] MS vino_2 NL: 9.37E ms [ ] MS vino_2 NL: 1.2E ms [ ] MS vino_2 NL: 7.88E ms [ ] MS vino_2 NL: 3.96E ms [ ] MS vino_2 NL: 2.22E ms [ ] MS vino_2 HPLC-ESI-MS (SIM) profiles of phenolic compounds present in resolubilizedspray-dried wine samples.

20 CONCLUSIONS Microencapsulation techniques are becoming widespread in food and beverage industry, in consideration of their numerous advantages, some of them being preservation from microbial and environmental contamination, elimination of interferences, concentration of bioactive ingredients. In this study, red wines from the cultivar Nero d Avola were subjected to spray-drying technology and successively analyzed by GC/MS and LC/MS, for the assessment of the volatile and phenolic composition. The purpose of the study was basically to evaluate if the spray-drying process somehow affects the important components of aroma and phenolics. The results here obtained evidenced a marked reduction of odour active compounds in microencapsulated wines, after resolubilization in water/ethanol; when considering the total amount of volatiles a twofold reduction was observed. Conversely, the qualitative analysis of polyphenols showed no influence of the spray-drying process on these functional constituents, thus confirming the efficiency of microencapsulation in the isolation and concentration of bioactive molecules. The results here presented give a hint for the development of a sustainable wine product, namely a wine powder, which could be exported worldwide with a considerable cost reduction due to the elimination of the liquid volume. Prior to selling/consumption, the wine powder can be safely reconstituted as normal wine through the addition of a hydroalcoholic solution. The final product, as shown in this report, might have a slightly poorer aroma, but would certainly remain a wine of acceptable quality.