UNIVERSITÀ DEGLI STUDI DI FOGGIA DIPARTIMENTO DI SCIENZE AGRARIE, DEGLI ALIMENTI E DELL AMBIENTE TESI DI DOTTORATO DI RICERCA IN BIOTECNOLOGIE DEI PRODOTTI ALIMENTARI (XXVII CICLO) COORDINATORE: PROF. MATTEO ALESSANDRO DEL NOBILE Production of high-qulity red wines from ntive vines through the mngement of viticulturl, technologicl, ging nd pckging vribles PhD student: Dr. Antonio De Ginni Tutor: Co-tutor: Dr. Antoniett Bino Prof. Ennio L Notte Dr. Dontell Nrdiello ANNO ACCADEMICO 2011-2014 - 0 -
SUMMARY Chpter 1 - Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine....- 4-1.1 Txonomic clssifiction... - 5-1.2 Morphology of grpevine.. - 6-1.2.1 The Root System...- 6-1.2.2 The Trunk..- 7-1.2.3 Shoots nd Cnes...- 8-1.3 Grpe berry growth.....- 12-1.4 Grpe Composition......- 15-1.5 Vineyrd ecosystem nd wine qulity....- 17-1.5.1 Vineyrd..- 18-1.5.2 Territory...- 19-1.5.3 Climte...- 20-1.5.4 Trining system... - 21-1.5.5 Nutrition nd irrigtion... - 22 - Chpter 2 - History, geogrphy, nd economics of grpe wine derived from red berry.- 23-2.1 Wine history.....- 24-2.2 Wine geogrphy nd economics.....- 24 - Chpter 3 - Red-wine winemking nd ging technologies.. - 28-3.1 Winemking technologies.... - 29-3.1.1 Addition of co-pigments, enzymes, nd tnnins.....- 29-3.1.2 Crbonic mcertion... - 33-3.1.3 Co-winemking... - 33-3.1.4 Cryomcertion... - 35-3.1.5 Délestge.....- 37-3.1.6 Prolonged mcertion..- 38-3.1.7 Signée....- 39-3.1.8 Thermovinifiction..- 40-3.2 Aging technologies...- 41-3.2.1 Wine ging in ok brrel.- 41-3.2.2 Wine ging using wood frgments..- 43-3.2.3 Wine ging using micro-oxygention.- 47 - - 1 -
3.2.4 Wine ging on lees..- 49-3.2.5 Wine ging in mphore.- 51-3.2.6 Wine ging in bottles......- 52 - Chpter 4 - Pckging systems... - 56-4.1 Wine pckging: brief history.....- 57-4.2 The min problems of wine shelf-life.....- 57-4.3 Glss bottle nd glss bottle closures.....- 59-4.4 Other pckging mterils......- 65-4.4.1 PET bottles......- 66-4.4.2 Bg-in-Box (BIB) - 67-4.4.3 Lminted pperbord continers... - 68-4.4.5 Metl cns... - 68 - Chpter 5 - Aims of the reserch....- 70 - Chpter 6 - Mterils nd Methods...- 73-6.1 Red grpes.... - 74-6.1.1 Aglinico.....- 74-6.1.2 Montepulcino.- 75-6.1.3 Uv di Troi....- 77-6.2 Lef removl tretment... - 78-6.2.1 Vineyrd site... - 78-6.2.2 Lef removl tretments nd lef re evlution... - 79-6.2.3 Field mesurements.....- 79-6.2.4 Grpes nd winemking......- 80-6.3 Micro-oxygention nd tretment with ok chips....- 81-6.4 Comprison mong winemking procedures....- 81-6.5 Comprison mong severl types of closure hving different permebility..- 83-6.6 Timing of the tretment with ok chips.- 84-6.7 Tretment with ok wood chips combined with other processing..- 85-6.8 Anlyticl determintions...- 85-6.8.1 Physicl-chemicl nlysis..- 85-6.8.2 Colour mesurements nd structure indices - 86-6.8.3 Determintion of phenolic compounds nd ntioxidnt ctivity....- 86-6.8.4 HPLC-DAD-ESI-MS/MS nlysis of phenolics.- 87-6.8.5 HS-SPME-GC-MS nlysis of free voltile compounds - 89 - - 2 -
6.9 Sensory descriptive nlysis....- 90-6.10 Sttisticl nlysis..- 91 - Chpter 7 - Results nd Discussion...- 92-7.1 Study of the effects of defolition on composition of Uv di Troi (Vitis vinifer L.) grpe nd wine...- 93-7.2 Evlution of tretment with ok chips nd micro-oxygention on colour stbiliztion nd phenolic evolution of wines derived from ntive red grpe cultivrs - 109-7.2.1 Aglinico wines.- 109-7.2.2 Montepulcino wines - 128-7.2.3 Nero di Troi wines...- 145-7.3 Influence of winemking technologies on chemicl nd sensoril prmeters in ntive wines......- 167-7.4 Effect of the tretments with French ok chips performed before or fter the mlo-lctic fermenttion on Nero di Troi wine qulity..- 178-7.5 Study of single nd interctive effects of lef removl nd ging with French ok chips on physicl, chemicl, nd sensory chrcteristics of Nero di Troi wines..- 191-7.6 Evlution of single nd interctive effects of the winemking technologies nd tretment with ok chips on colour, phenolic composition nd sensory profile of Nero di Troi wines... - 208-7.7 Evlution of single nd interctive effects of the tretment with ok chips nd different types of closure on Nero di Troi wine qulity.- 227 - Chpter 8 - Conclusions...- 246 - References.....- 250 - - 3 -
Chpter 1 Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine - 4 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine 1.1 Txonomic clssifiction Grpevines re grouped in the genus Vitis, fmily Vitcee tht lso includes two wellknow species, such s Boston Ivy (Prthenocissus tricuspidt) nd Virgini Creeper (P. quinquefoli). The Vitcee fmily comprises more thn thousnd tropicl nd subtropicl species, subdivided in 15 or 16 gener (Glet, 1988). The genus Vitis grows in temperte-zone nd develops indigenously only in the northern hemisphere. It ws divided into two subgener, Vitis nd Muscdini. Vitis (bunch grpes) is the lrger of the two subgener, including ll species except V. rotundifoli nd V. popenoei. These ltter two species re included in the Muscdini subgenus. The subgenus Vitis includes species which re chrcterized by shredding brk without protubernt lenticels, medull interrupted t nodes by woody tissue, phloem fibers tngentilly positioned, brnched tendrils, elongted flower clusters, fruit dhering to the fruit stem t mturity, nd pershped seed hving smooth chlz nd protubernt bek (Jckson, 2008). The grpevine species (Vitis vinifer L.) is the single Vitis species tht ttined significnt economic importnce over time, while some other species, i.e. the North Americn V. rupestris, V. ripri or V. berlndieri, re used s breeding rootstock due to their resistnce ginst grpevine pthogens such s Phylloxer, Oidium nd mildews. Indeed, most of the cultivted vrieties, clssified s Vitis vinifer L. subsp. vinifer (or stiv), derive from the wild species Vitis vinifer L. subsp. sylvestris (Gmelin) Hegi (Rossetto et l., 2002; Sefc et l., 2003; Crespn, 2004). This wild grpevine is heliophilous vine distributed in wide re from the Western Europe to the Trns-Cucsin zone nd round the Mediterrnen bsin (Arnold et l., 1998). Its current distribution is highly frgmented in seprted micro-popultions or met-popultions, with few individuls, t lest in the western prt of the Mediterrnen Bsin. The progressive decline of the wild grpe popultions my be explined by the nthropogenic pressure on their nturl hbitts nd by the presence of pthogens introduced from North Americ during the second prt of the 19 th century (Arnold et l., 1998). Indeed, the Phylloxer crisis tht ffected the Europen vineyrds hd considerble impct on both cultivted vrieties nd wild grpes. The common grpevine is the only common species of the series Vinifer nd hs Eursin origin. It is lso present s spontneous species. Within the species, there re two subspecies: - 5 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine Vitis vinifer subsp. stiv, with hermphrodite plnts nd bisexul flowers. It is the subspecies tht includes the cultivted vrieties; Vitis vinifer subsp. sylvestris, with dioecious plnts. It is the spontneous subspecies, widespred in woodlnds nd scrub wrm temperte regions of the Eursi. From the gronomic point of view, this subspecies is entirely devoid of interest (http://it.wikipedi.org/wiki/vitis_vinifer). 1.2 Morphology of grpevine The shpe of cultivted grpevine is creted by pruning nd trining of the vine into specific form ccording to one trining system. Over the centuries, severl trining systems hve been developed nd modified in the efforts to simplify vine mngement nd offer fvourble growing environment for grpe production (Hellmn, 2003). 1.2.1 The Root System The root system of the plnt, besides to ct s grip in the ground, serves to bsorb wter, provide nutrients for its sustennce, produce hormones nd retin nutrients, such s sugrs, in cse of need. The roots of ripe vine re formed from woody texture of old roots (Richrds, 1983) from which originte young nd permnent roots tht my develop both horizontlly or verticlly. These roots re generlly multi-brnched nd could led to lterl roots. The ltter produce fine roots, which hve the effect of incresing the mount of lnd used. The root system usully extends bout 3 feet into the ground, lthough some roots cn spred more in depth (but this depends on the climtic conditions). Distribution of roots is conditioned by fctors such s chrcteristics of the soil, presence of impermeble lyers, vriety of the vine, rootstock, nd gronomic prctices. Mycorrhize, form of soil fungi, live in nturl, mutully beneficil ssocition with grpe roots. Mycorrhize influence grpevine nutrition nd growth nd increse the uptke of phosphorus. grpevine cn be grown on its own roots (roots screws or self-rooted) or cn be grfted onto rootstock. A screw engged (Figure 1) is divided into two prts, the scion vriety (for exmple, Pinot noir), which produces the fruit, nd the vriety rootstock (often indicted with number, for exmple, 101-14), which provides the root system nd the lower prt of the trunk. The position on the trunk where the two vrieties were grfted nd - 6 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine from which they grow together is clled grft union. A successful union requires tht the vsculr cmbiums of stock nd scion re in contct with ech other, since these re the only tissues hving meristemtic ctivity nd thus ble to produce the new cells tht complete the union of the grft. The point of union of the grft often include the production of bundnt cllus tissue ( tissue wound heling composed of lrge cells with thin wlls tht re formed in response to injury), which often mke the re bit bigger thn the prts djcent to the trunk itself. Since the vriety of the rootstock nd the scion cn grow t different rtes, the dimeter of the trunk cn vry bove nd below the grft union. Rootstock ws born to counter North Americn insect, Viteus vitifolii, better known s Phylloxer, to which the roots of the Vitis vinifer L. (wine grpes "Europen") were sensitive. The solution ws to grft Europen vines, ble to produce qulity wines, on foot with vines or its hybrids, resistnt to ttck of Phylloxer. This method is still of generl ppliction. Most rootstock resistnt to Phylloxer re ntive North Americn species or hybrids of two or more of these species, including V. ripri, V. berlndieri, nd V. rupestris. The root system nd the depth tht cn be chieved, s well s other fetures, vries ccording to the species nd hybrid rootstocks, so the rootstock cn influence spects of the growth of the vine, such s vigor, drought tolernce, efficiency of nutrient bsorption, nd bility to resist to the ttcks. 1.2.2 The Trunk The trunk or stem is permnent nd supports the structure of the vegettive nd reproductive grpevine. It is minly verticl, but my hve different inclintions depending on the type of frming. The upper prt of the trunk is indicted s hed nd its height is due to the pruning during the initil stges of formtion of the young grpevine. The trunk hs rmifictions re clled shoots when they re herbceous, brnches when they re lignified, nd srments when they re detched from the plnt fter pruning. The brnches, in their turn, re constituted by nodes nd internodes in number nd vrible length. The rmifictions re locted in different positions depending on the system. Some trining systems using cords (semi-permnent brnches of the trunk) usully were trined horizontlly long trellis wire, with rms plced t regulr intervls long their length. Other systems utilize pipes (Figure 1), one-yer-old wood tht origintes from the rms usully locted ner the hed of the screw. The crown is the re of the trunk ner the ground, from slightly below to slightly bove the ground level. - 7 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine Figure 1 Grpevine structures nd fetures: grfted vine (source: Hellmn, 2003). 1.2.3 Shoots nd Cnes Shoot is the bsic unit of the growth of the vine nd the min key of mny griculturl prctices. The components of the shoot re illustrted in Figure 2. The min xis of the shoot consists of structurl support tissues nd conduction tissues for the trnsport of wter, nutrients nd products of photosynthesis. Leves, tendrils, flowers (or fruits), nd buds re plced long the shoot in regulr ptterns. The res of the shoots re defined s bsl (closest to its point of origin), mid-shoot, nd pex (tip). The word cnopy indictes the whole of vine shoots, leves nd fruits; some viticulturists lso think tht trunk, cordons, nd cnes re prts of the cnopy. Shoot Tip. A shoot hs different points of growth, but normlly they extend from the shoot tip (growing tip). New leves nd tendrils born from the tip s the shoot grows. The shoot growth rte vries during the seson. If the suitble conditions of light, moisture, nd nutrients re suitble, the shoots of the grpevine cn continue to grow. In fct, they don t block their expnsion by forming terminl bud, s some plnts do. Leves. The vine leves re simple, lternte, nd with generlly segmented distichous edge. They originte from the picl meristem. The shoot gives rise to two or more brcts close-ups (smll scle-like leves) formed t the bse of the first true folige lef. The leves re joined to the slightly enlrged surfce on the shoot clled node. The re between two nodes is clled internode. The distnce between the nodes is n indictor of - 8 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine the rte of shoot growth, so internode length vries long the cne corresponding to chnging growth rtes during the seson. Leves re formed by the blde, which is the upper prt of the lef responsible of sunlight nd CO2 bsorption during photosynthesis, nd of the petiole, the stemlike structure tht links the lef to the shoot. The diffusion of CO2, O2, nd wter vpour tkes plce through the stomt, microscopic pores locted in the lower prt of the lef bldes. Stomt re open in the light nd closed in the drk. The petiole hs the function of mintining the orienttion of the lmin nd to convey nutrients nd wter to nd from the lef blde. Figure 2 Principl fetures of grpevine shoot prior bloom (source: Hellmn, 2003). Flowers nd Fruits. A fruitfl shoot usully mkes from one to three flower clusters (inflorescences) ccording to the vriety. Flower clusters grow opposite to the leves, typiclly t the third to sixth nodes from the bse of the shoot, depending on the vriety. If three flower clusters develop, two develop on djcent nodes, the next node hs none, nd the following node hs the third flower cluster. The number of flower clusters on the shoot is influenced by grpe vriety nd the conditions in which the plnt hs undergone during the previous seson, s these ffect the development of the dormnt bud (tht produced the primry shoot). A cluster my contin from severl to mny hundreds individul flowers, depending on vriety. The grpe flower is not formed by mny petls, which, however, re merged into green structure defined the clyptr (Figure 3) but commonly clled cp. This contins the reproductive orgns nd other tissues inside the flower. A flower is formed by single - 9 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine pistil (femle orgn) nd five stmens, ech tipped with n nther (mle orgn). The pistil hs conicl shpe, with the much lrger bse of the upper prt nd the tip (the stigm) slightly flred. The bse of the pistil is formed from the ovry tht is divided into two internl res, ech of which contins two ovules in which there is embryonic bg with single egg. The nthers mke yellow pollen grins, which contin the sperm. Figure 3 - A grpe flower shedding its clyptr (flower cp) during nthesis (source: Dokoozlin, 2000). The flower cn remin open 1-3 weeks depending on wether conditions. This period is nmed the bloom, which hppens between the 50 th nd the 80 th dys fter germintion. When flower opens, the cp is detched nd flls off, thus exposing the pistil nd the nthers. The ltter issue the pollen flling on the stigm rndom. This process is clled pollintion. Multiple pollen grins cn germinte, ech growing pollen tube down the pistil to the ovry nd entering n ovule, where sperm unites with n egg to form n embryo. This is the fertiliztion nd the subsequent growth of fruits is the fruit set. Tendrils. Shoots give rise to tendrils, structures tht re responsible for providing support to the shoots during their growth. Flower clusters nd tendrils hve common developmentl origin (Mullins et l., 1992), so occsionlly few flowers develop on the end of tendril. Buds. The bud is the point of growth tht develops just bove the point of link between petiole nd shoot (lef xil). The single gem is clled xillry bud nd two buds ssocited with lef defined lterl bud nd dormnt bud. The lterl bud is the true xillry bud of the folige lef, nd the dormnt bud forms into the brct xil of the lterl bud. The lterl bud grows in the current seson, but growth my either cese soon fter formtion of the bsl brct or continue, producing lterl shoot (summer lterl) of highly vrible length. - 10 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine The dormnt bud ppers s simple structure, being mde up of three points of growth, indicted s primry, secondry, nd tertiry buds. It is clled dormnt becuse it doesn t grow in the sme seson in which it develops. The three growing points ech produce rudimentry shoot tht ultimtely will contin primordi (orgns in their erliest stges of development) of the sme bsic components of the current seson s fully grown shoot: leves, tendrils, nd in some cses flower clusters. In most cses, only the primry bud grows, producing the primry shoot, while the secondry nd tertiry bud re s bckup system for the grpevines nd grows only when the primry bud or young shoot is dmged. Specificlly, tertiry bud provide dditionl bckup if the primry nd secondry buds re dmged, but usully does not contin flower cluster. If only the primry grows, secondry nd tertiry buds remin live but dormnt. Figure 4 Cross section of dormnt grpe bud in lef xil, showing primry, secondry, nd tertiry buds (source: Hellmn, 2003). Suckers nd Wtersprouts. Shoots my lso come from bud plced on old wood, such s cordons nd trunks. Suckers re shoots tht grow in the crown of the trunk. Wtersprout indictes shoot deriving from the upper regions of the trunk or cordons. The shoots tht grow on old wood develop s xillry buds tht hve never bloomed. These buds re clled ltent buds, becuse they cn remin dormnt indefinitely until n extreme event does not stimulte their development. In generl, there re mny hidden gems in the renewl positions ( term pruning) on the trunk or Cordons. Cnes. Shoot begins trnsition of midseson, when it begins the ripen. Once the leves fll t the beginning of the dormnt seson, the mture bud is considered cne. Cne is the min priority in the period of vegettive rest, when the prctice of pruning is used to - 11 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine hndle the size nd the shpe of the vine nd to check the mount of potentil crop in the next hrvest seson. Pruning severity is often described in terms of the number of buds retined per vine, or bud count. The crown of buds observed t the bse of cne includes the secondry nd tertiry growing points of the compound bud tht gve rise to the primry shoot, s well s the xillry buds of the shoot s bsl brcts (Prtt, 1974). Cnes cn be pruned to vrying lengths, nd when they consist of only one to four buds they re referred to s spurs, or often s fruiting spurs since fruitful shoots rise from spur buds. 1.3 Grpe berry growth Grpe flowers re borne on n inflorescence or flower cluster (Figure 5). The rchis is the min xis of the cluster nd through the peduncle the flowers re tied to it. The pedicle connects the cluster to the vine, which is prolonged from the bud to the first brnch of the rchis. Almost ll the most commercilly importnt Vitis vinifer grpe vrieties flowers re hermphrodite, contining both the mle nd the femle orgns (Figure 5). The cup is gmoseplo, underdeveloped, divided into five sepls brely visible. The coroll consists of 5 inconspicuous, greenish, welded petls; t the time of flowering, coroll often opens with petls tht unsolder from the bse to the pex, nd soon flls. The ndroecium consists of five stmens with dorsifixed nthers with longitudinl dehiscence. In hermphrodite flowers, the nthers re rrnged t the height of the stigm, but re outwrd-fcing, so the pollintion of the vine tends to be predominntly cross. The gynoecium consists of two-roomed ovry contining 4 ovules; the ovry is surmounted by stylus ending with bi-lobed stigm. At the bse of the flower, there re five scent glnds, commonly clled nectries, ltohugh they don t produce nectr. These glnds re responsible for producing substnces tht re designed to ttrct insects, but in Vitis vinifer vrieties, the substnces produced seem to get little ttention from insects (Dokoozlin, 2000). - 12 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine Figure 5 - A typicl flower cluster prior to nthesis (to left); hermphroditic perfect grpe flower (to right) (source: Dokoozlin, 2000). Anthesis. The clyptr, formed by five fused petls, hs the function to protect the flower orgns. The process of opening of the flower is clled nthesis nd consists in the clyptr breking from the bse of the flower with the exhibition of the stmens nd pistil. Anthesis lsts 6-8 weeks from the moment in which the shoots born. Its durtion vries vry depending on the wether (Dokoozlin, 2000). Pollintion, fruit set nd verison. Pollintion is the trnsfer of pollen from the nther to the stigm. It is utogmous nd cleistogmic, thus it tkes plce inside the ovry. The first visul indiction tht pollintion is occurring is when the cp flls from the flower. The pollen is relesed from the mture nthers. This is termed cp fll nd flowering is generlly determined s when 80% cp fll occurs (80% of the cps in cluster hve fllen). The pollen flls onto the stigm, then develops tube which grows down the style to the ovry to llow the mle nucleus to trvel to the femle nucleus nd fertilistion to tke plce. Fertilistion, which consists in the union of mle nuclei from the pollen with the femle nuclei in the ovry, generlly occurs 2-3 dys fter pollintion. The embryo nd berry development begins. The embryo forms the seeds nd the ovry becomes the berry (http://it.wikipedi.org/wiki/vitis_vinifer). After pollintion nd subsequent fertiliztion, the fruit set follows. This phse consists in the trnsformtion of flowers into fruits. Up to 70-80% of the flowers my fil to set. The size of the berry is minly determined by the number of seeds it contins. The lrger fruits re those contining more seeds. A berry my contin up to four seeds, lthough two or less is usul in the wine grpe vrieties. Berries with pistils tht hve not been fertilised - 13 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine will bscise (brek off) from the cluster. This is termed shtter. Normlly up to 50% of the potentil fruit my shtter, preventing the bunch from becoming too compct. Smll seedless berries, which don t enlrge, my remin on the cluster in some vrieties. These berries re termed shot berries, resulting in hen nd chickens or millerndge). In some grpe vrieties, the fruit cn develop without seeds. This is clled prthenocrpy. This occurs in Blck Corinth vriety. Stenospermocrpy occurs in other vrieties (eg. Thompson Seedless vriety used for tble grpes, dried fruit, nd wine). Fertilistion occurs, but the seeds re smll, soft nd empty. The berries develop to medium size (http://it.wikipedi.org/wiki/vitis_vinifer). After the fruit set phse, the herbceous ending follows from the first hlf of July nd the first hlf of August, lwys in reltion to fctors of precocity nd geogrphicl position. At this stge there is the growth of the berries size nd weight, up to the mximum vlues. The growth of the seeds lso occurs, up to the chievement of the finl dimensions. At this stge, grdul increses of sugr content (2%) nd orgnic cids (4%) occur in the pulp. Verison follows the herbceous phse. This stge is chrcterized by the skin colour chnge. During verison, biochemicl processes nd reorgniztion of tissues lso occur. The proper growth hs cesed, lthough n increse in volume of the berries cn be observed. The most importnt phenomen occurring in this phse re the following: disppernce of chlorophyll. The green colour disppers grdully being replced by the colour of the other pigments (nthocynins nd crotenoids). The rtio between the vrious pigments chnges mong the grpe cultivrs. As result, the colour chnges from green to yellow in white grpes, nd the colour chnge from green to red or purplish red, in blck grpes; sugr ccumultion. This phse occurs s result of trnsloction of sugr from other orgns (ccording to some uthors from reserves locted in the wood, ccording to others from the leves); loss of consistency of the mesocrp (pulp). This is due to the grdul disintegrtion of the middle lmell, which joins the cell wlls of djcent cells. In grpes juicy pulp is lso drstic reorgniztion with the brekup of the cell wlls (http://it.wikipedi.org/wiki/vitis_vinifer). Grpe Ripening. The grpe ripening is influenced by severl fctors, including vriety, climte, nd crop level. The specific number of het units (frequently expressed s degree- - 14 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine dys [DD]) necessry for berry mturtion strongly differs mong vrieties. Sesonl modifictions in degree-dy ccumultion lso ffect the rte of ripening. When tempertures re low nd degree-dy ccumultion trdy, ripening is retrded, while when conditions re wrm nd degree-dys ccumulte fst, ripening is quicker (Dokoozlin, 2000). 1.4 Grpe Composition Wter. Wter usully contributes 70 to 80% of berry fresh weight t hrvest. Berries trnspire lrge mounts of wter during their development. Prior to verison, most of the wter required by the fruit is supplied by the xylem. After verison, the phloem becomes the primry supplier of wter to the berry becuse of the blocking of the xylem vessels entering the berry. Sugr, minerls, nd other compounds entering the fruit during ripening re lso supplied by the phloem (Dokoozlin, 2000). Sugrs. Sugr (in the form of sucrose) provides the crbon structure for the synthesis of mny compounds, such s orgnic nd mino cids. Sucrose, the predominnt sugr trnsported in the phloem, is mde by joining one molecule of glucose with one molecule of fructose. It is synthetized in leves nd, from the initition of ripening until hrvest, it is trnsported minly to fruit. Once sucrose reches the berry it is hydrolized to glucose nd fructose, which re present in pproximtely equl mounts in grpe berries t hrvest, ech rnging from 8 to 12% of fruit fresh weight. During the initil stges of fruit growth, the berry sugr content is quite low, usully round 2% of the berry fresh weight. Sugr concentrtion strts to increse rpidly t beginning of the onset verison, nd my rech 25% or more of the berry fresh weight by the time of hrvest (Dokoozlin, 2000). Orgnic cids. Trtric nd mlic cids re the min orgnic cids of the grpe berry, mking up pproximtely 90% of the totl fruit cidity. Both cids re produced in the berry, long with smll mounts of citric cid nd severl other non-nitrogenous orgnic cids. The concentrtions of trtric nd mlic cid, nd totl cidity progressively increse during the fruit development until just before the beginning of fruit ripening, reching the highest vlues ner verison, nd decrese during the ripening phse. Trtric cid is stble fter its synthesis since no degrdtive enzyme hs been found in berry. Nevertheless, the concentrtion of trtric cid decreses during ripening due to the dilution effect, since berry volume increses while the mount of trtrte per berry remins constnt. Insted, mlic cid cn be respired by severl enzymes in the berry to form CO2 nd H2O. Thus, its - 15 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine concentrtion decreses fter verison becuse of respirtion nd enzyme degrdtion s well s dilution. Moreover, the content of free trtric nd mlic cids in the berry decrese during ripening due to the formtion of cid-slts with potssium nd other ctions in the berry. Temperture is key fctor controlling berry cid content. During the initil phses of fruit growth, the optimum temperture for cid synthesis rnges between 20 nd 25 C. It is lso well recognized tht fruit cidity t hrvest is negtively correlted with temperture during the ripening period. Generlly, grpes ripened t low tempertures hve greter totl cidity (in prticulr mlic cid) thn those ripened t high tempertures. Therefore, grpe cidity differs mong regions nd yers, with the higher vlues in growing sesons nd regions chrcterized by cold tempertures (Dokoozlin, 2000). Juice ph. The juice ph is reltively constnt during the primry stges of berry development, with vlue round 2.5, then increses grdully s cid nions re formed nd the concentrtion of mlic cid in the berry decreses (Dokoozlin, 2000). Phenolic compounds. Phenolic compounds include tnnins, flvonols, nd nthocynins, the ltter re responsible for grpe colour. These compounds re synthesized in the berry nd locted especilly in the skin, but lso in seeds. Red grpe vrieties contin much greter concentrtions of phenolic compounds thn white grpes, since the ltter does not contin nthocynins. Phenolics re importnt constituents of the grpe berry becuse they determine fruit colour nd stringency. The oxidtion of cftric cid, the mjor phenolic compound present in grpe pulp nd juice, determine the formtion of brown pigment (Dokoozlin, 2000). Nitrogen compounds. In grpe berries, nitrogen is minly present in the form of mmonium ions (NH4 + ) nd orgnic nitrogen compounds (mino cids nd proteins), nd little mount of nitrte (NO3). During the initil phses of berry development, mmonium ions represent more thn hlf of the fruit totl nitrogen, nd mino cids content is rther low. After verison, the mmonium concentrtion declines due to the incorportion of the ions into mino cid. The mino cid concentrtion of the berry my increse from two- to fivefold during ripening, ccording to the vriety nd fruit mturity. Arginine nd proline re the min mino cids present in most grpe vrieties (Dokoozlin, 2000). Inorgnic minerls. The inorgnic minerls in grpe berries include the ctions potssium, clcium, nd sodium, nd the nions phosphte nd chloride. They derive from the soil nd re trnsported from roots to fruits vi xylem (before verison) or phloem. - 16 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine During ripening the concentrtion of minerl ction increses from two- to threefold (Dokoozlin, 2000). Arom nd flvour compounds. The type nd concentrtion of rom nd flvour compounds in berries re strongly dependent on grpe vriety. Monoterpenes re the bestknown nd best-described flvour compounds of Vitis vinifer. They ccumulte during the ltter stges of ripening nd re responsible for the flowery notes (Dokoozlin, 2000). 1.5 Vineyrd ecosystem nd wine qulity Fctors ffecting the vineyrd cultivtion re certinly relted to territory nd climte, but the mn s hnd blends ll the components. This represents wht French cll Terroir. In other words, ccording to the Fregoni s scheme (1985; Figure 6), it is possible to ffirm tht the min fctors ffecting wine qulity re: vineyrd: choice of the grpevine cultivr (rootstock, clone); lnd (or territory): ltitude, exposure to the sunlight (topogrphy), soil profile, soil structure nd composition, zoning ccording to suitbility (mountins nd hills re better thn plin nd res close to rivers); climte: mcro- nd micro-climte; humn nd viticulturl fctors: pruning, fertilizing, trining systems. Figure 6 Fregoni s scheme (source: Fregoni, 1985). - 17 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine 1.5.1 Vineyrd For qulity wine, the choice of vine is necessrily linked to the territory in which wine itself will be produced. In fct, the most successful wines re those produced from grpes tht re perfectly integrted into the soil nd climte environment. The current legislture imposes disciplinry, therefore to produce is required the implnting of the vrieties uthorized nd/or recommended by the regultions nd especilly select the ntive cultivrs. The current trend is to mke use of the so-clled interntionl vrieties, often esier to implnt nd more consistent in production. Nevertheless, qulity Itlin vrieties re the rel point of reference for qulity wine production. The selection of the best clones will led to low production, clusters smller nd more compct, nd t higher concentrtion of substnces to be extrcted during vinifiction. For the vine cuttings propgtion, the grfting technique is used. The elements re the rootstock or foot, which represents the portion of the plnt provided with rdicl pprtus, nd then the scion, portion of brnch with one or more gems, which is welded into plce. The most known grfting methods re: English double-slit (omeg), employed in Centrl/North Itly; Mjorcn (bud), used minly in Southern nd Islnd Itly nd performed directly on the plnt (http://www.vinoinrete.it/sommelier/sommelier%20-1- %20viticolturhtm). For the grpevine selection, it is necessry to conduct study of the environmentl chrcteristics to identify the best rootstock, which will better dpt to the conditions (such s humidity, drought, het, cold, wind, nd so on). At the sme time it will be very importnt the choice of grft becuse it proves fruitful nd helthy. Around the end of 1800s, Vitis Lbrusc from Americ ws hiding serious disese for the vines: Phylloxer, pest tht ttcked the roots nd slowly destroyed the Europen species. There ws n environmentl ctstrophe nd ll the vineyrds died lmost. The ttempts to resolve the problem turned out to be filure fter nother, until they begn to replnt vines dopting the technique of grfting Europen ntive scion onto Americn rootstock, becuse the phylloxer did not ttck the Americn roots. - 18 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine Nevertheless it remins some fine locl grpe vrieties such s Nebbiolo nd Brber tht hve been sved, especilly t high ltitudes or ner the sndy res where Phylloxer does not proliferte. Currently, Chile is the only country foot-ex in the world. Rootstocks ffect vine vigour, s well s influence vine nutritionl nd hormonl blnce. Rootstock selection cn lso ffect the potentil wine qulity by improving vine helthy sttus (incresing resistnce or tolernce to severl pests, diseses nd dverse environmentl conditions) (Jckson, 2009). 1.5.2 Territory Ltitude. The most of the world s wine producing regions is locted between the temperte ltitudes of 30 nd 50 in both hemispheres. Grpes, lthough re tempertezone plnts, cn be lso cultivted under semitropicl conditions. They cnnot grow to the cooler prts of the temperte zone, where the sesonl growing time my be too short to llow the fruit to rech mturity or where low winter tempertures (less thn -7 C) my kill the vine or its fruitful buds (http://fnbservicenotes.wordpress.com/2012/07/26/fctorsffecting-qulity-of-wine/). Loction/Topogrphy. Vines give better grpes in the hills thn in the plins. The slope of the ground, clled rrngement, provides higher dringe nd increse the impct of the sunry, thus improving vegettive development nd fruit ripening. At higher ltitude, the slope must ibe higher. In plin re, the sun exposure is lower s spred over lrger re, spring frosts re more frequent nd very dngerous when the plnt begins to sprout. Another importnt topogrphic element is the exposure: the vineyrds fce south hve greter sun exposure nd then such provision shll be sought, especilly in northern res. The locl climte could be ffected lso by the presence of mountins, forests, rivers nd lkes tht protect the vineyrds from cold winds, provide reservoir of moisture during the hot seson nd ply n importnt thermoregultory ction (http://www.vinoinrete.it/sommelier/sommelier%20-1-%20viticolturhtm). Soil. The soil consists of thin lyer tillble, influenced by the cultures of mn, nd prt below the chrcteristics of which re given from the geologicl origin. The soil composition is one of the most importnt viticulture spects when plnting grpe vines. The chrcteristics of soil re importnt becuse it supports the root structure of the vine nd influences the dringe levels nd mount of minerls nd nutrients tht the vine is - 19 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine exposed to. The idel condition for vine is n re of thin topsoil nd subsoil tht sufficiently retins wters but lso hs good dringe so tht the vine roots don t become overly sturted. The bility of the soil to retin het nd/or reflect it bck up to the vine is lso n importnt considertion tht ffects the ripening of the grpe. The composition of the soil hs n influence on soil temperture, root penetrtion, wter holding cpcity, nd vine nutrition. The stony-permeble soil ensures dringe nd good mturtion of the grpes. In ddition, pebbles, less fertile, force plnt to sink its roots into the ground nd then llow the enrichment of grpes nd the wine in minerl extrcts. The soil colour is n nother essentil spect: drk-coloured soils wrm up nd fvour the ripening of the fruit while cler ones re cooler, slow ripening nd then promote wines of higher cidity (http://www.vinoinrete.it/sommelier/sommelier%20-1-%20viticolturhtm). There re severl minerls tht re vitl to the vines nd tht good vineyrd soil must hve. These include: clcium, which helps to neutrlize the soil ph levels; iron which is essentil for photosynthesis; mgnesium, which is n importnt component of chlorophyll; nitrogen, which is ssimilted in the form of nitrtes; phosphtes. which encourges root development; nd potssium, which improves the vine metbolisms nd increses it helth for the next yer s crop. While subsoil lwys remins geologiclly true, topsoil composition cn be enhnced using mnure or fertilizer. Moreover, the degree of cidity of the soil is not overlooked: in Europe the best wines re produced from lkline nd clcreous soils, while in Cliforni they re produced from neutrl or cidic soils. 1.5.3 Climte The vine is very resistnt plnt nd its bility to dpt to vrious climtic conditions llow better development of the vine in reltion to the production of qulity wine. The verge nnul tempertures must not be below 10 C with n verge vlue round 20 C in summer nd -1 C in winter. The mount of het is very importnt since it is preferble stedy ripening tht produces frgrnt nd blnced wines. The key issue is lso the winter cold, s it promotes both the mturtion of the wood tht the deth of prsites. Frost is the most fered climtic condition becuse in lte spring it cn dmge the new shoots, thus reducing the size of the crop. Methods to combt frost include propeller bsed rind dispersers to disturb ir (frost will only occur in still conditions), setting burning stoves (smudge pots) between rows of vines to bet the ir, nd spersionrepetedly sprying vines with wter to keep them bove 0 C. - 20 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine Another importnt climtic vrible is rinfll, becuse it keeps the soil moist nd encourge the ripening of the fruit, especilly when concentrted in winter nd spring, with cool tempertures. Insted, rins during flowering nd t hrvest time cn crete mny hzrds such s fungl diseses nd berries splitting. Concerning humidity, vlues round 60-80% re desirble while excessive moisture encourges diseses such s powdery mildew nd grey rot. The other prmeter to tke into ccount is the microclimte previling in single vineyrds or within smll regions. Microclimte is determined by the system of pruning, the distnce between plnts, the distnce between rows nd the distnce of plnts from soil. Rise nd fll of terrin, loction besides wter bodies such s lkes or rivers, presence of hills, mountins or forests s wind brekers re other determinnts of microclimte (Jckson, 2009). For exmple, the presence of lrge bodies of wter nd mountin rnges cn hve positive effects on climte nd, consequently, on vines. In fct, nerby lkes nd rivers cn serve s protection for drstic temperture drops t night by relesing the het stored during the dy to wrm the vines. Furthermore rivers my rise the mbient temperture of one or two vitl degrees. 1.5.4 Trining system Trining refers to techniques designed to position the fruit-bering shoots to optimize both fruit yield nd qulity, consistent with long-term vine helth. There re hundreds of trining systems, but few hve been studied sufficiently to estblish their efficcy. In contrst, severl modern trining systems, such s the Scott Henry, Lyre, Smrt Dyson, nd Genev Double Curtin (GDC), hve been shown to possess cler dvntges in improving both fruit yield nd qulity (Smrt nd Robinson, 1991). In ddition to incresing vine cpcity, fruit helth increses (reduced incidence of infection) nd cluster loction fcilittes economic mechnicl hrvesting. These fetures both enhnce qulity nd decrese production costs. The vine s inherent vigour must be restrined on reltively nutrient-poor, dry soils. This hs trditionlly been chieved by dense vine plnting (bout 4000 vines/h) nd severe pruning (removl of > 90% of the yerly shoot growth). However, on rich, moist, lomy soil, limited pruning is preferble with wide vine spcing (bout 1500 vines/h). Under these conditions, it is prudent to redirect the incresed growth potentil of the vine into - 21 -
Botnicl clssifiction, morphology, physiology of grpevine nd qulity of wine greter fruit production, not prune it wy. When n pproprite LA/F 1 rtio is estblished, incresed yield nd qulity cn exist concurrently. It is on rich soils tht the newer trining systems succeed so well. These systems not only chieve desirble LA/F rtio, but they lso provide improved exposure of the grpes to light nd ir. These fetures promote idel berry colortion, flvour development, fruit helth, nd flower-cluster initition. 1.5.5 Nutrition nd irrigtion Generlly, stressing the vines is often viewed s essentil to fine wine production. This view probbly rose from the reduced-vigour, improved-grpe qulity ssocition found in some renowned Europen vineyrds. However blncing vegettive nd fruit-bering functions is the rel gol. Exposing the vine to extended periods of wter or nutrient stress re lwys detrimentl. Eqully, supplying nutrients nd wter in excess is detrimentl, s well s wsteful. In prctice, regulting nutrient supply to improve grpe qulity is difficult. Becuse the nutrient demnds of grpevines re surprisingly smll (prtilly becuse of the nutrient reserves of the vine s woody prts), deficiency symptoms my not express for severl yers. Moreover, estblishing nutrient vilbility is still n pproximte science. Irrigtion cn be employed to control vine development nd encourge optiml fruit mturing. Irrigtion wter cn lso supply nutrients nd disese-control chemicls directly to the roots in specificlly mesured mounts nd t specific times. These possibilities re most pplicble in rid nd semi-rid conditions, where most of the wter supply comes from irrigtion (Jckson, 2009). 1 LA/F rtio: Lef Are/Fruit weight rtio. - 22 -
Chpter 2 History, geogrphy, nd economics of grpe wine derived from red berry - 23 -
History, geogrphy, nd economics of grpe wine derived from red berry 2.1 Wine history The history of wine dtes bck over 6000 yers BC. According to n ncient Persin fble, wine ws the ccidentl discovery of princess seeking to end her life with wht she thought ws poison (http://rmc.librry.cornell.edu/ewg/exhibition/introduction/). Archeologicl evidence suggests tht the erliest production of grpe wine took plce in Georgi nd Irn. The world s oldest known winery (dted to 3000 BC) ws discovered in Armeni (http://en.wikipedi.org/wiki/history_of_wine). The Egyptins were the first to record the process of wine mking on stone tblets nd on the wlls of their tombs but wine ws considered privilege of the upper clsses. In the ncient Greece, wine ws prised by historins nd rtists but, like the Egyptins, the ordinry citizens did not consume wine. With the Romn Empire, the production of wine spred throughout Europe nd wine becme vilble to the common citizens. The Romns did not drink pure wines but they dded flvours such s fermented fish suce, grlic nd onion. During the Drk Ages, wine production ws prerogtive of monsteries. The Benedictine monks becme one of Europen lrgest wine producers with vineyrds in Chmpgne, Burgundy, nd Bordeux regions (Frnce), s well s in the Rheingu nd Frnconi regions (Germny). The wine industry hd brief decline in the 17 th Century, while the 19 th century ws the golden ge for wine in mny regions, lthough, round 1863, mny French vines suffered from disese cused by the Phylloxer phid. When Americn vines were discovered s resistnt to Phylloxer, it ws decided to grft Europen vines on Americn rootstocks (http://www.wineinmodertion.eu/en/wine--culture-of-modertion/history-of-wine). The resulting products were mny hybrid grpes tht produced greter vriety of wines. The lst century hve seen n overll revolution in the wine industry, with the development of strong scientific bckground nd innovtion in equipment nd processing (http://www.rtmkers.com/wine/history.html). 2.2 Wine geogrphy nd economics Worldwide, the most diffused red grpe vrieties re in descending order: Grenche, Crignn, Merlot, Cbernet Suvignon, Rktsiteli, Bobl nd Temprnillo. Mny of these re of Europen origin. In our continent, the most prevlent grpe vrieties re: Temprnillo, Merlot, Grenche, Cbernet Suvignon, Syrh, Bobl, nd Sngiovese. Tble - 24 -
History, geogrphy, nd economics of grpe wine derived from red berry 1 shows the res under vines in Europe, divided by grpe vriety (EU Dt, Agriculturl Yer 2009/2010). Grpe vriety Totl Spin Frnce Itly Others Temprnillo 213 213 - - - Merlot 165 14 113 24 14 Grenche 155 67 88 - - Cbernet S. 101 22 54 16 10 Sirh 93 20 66 7 - Bobl 76 76 - - - Sngiovese 70 - - 70 - Crignn 50 6 44 - - Cbernet F. 41-36 4 1 Montepulcino 31 - - 31 - Pinot Noir 30-30 - - Gmy 29-29 - - Tble 1 Most cultivted red grpe vrieties in EU in thousnds of hectres (source: EU Dt, 2010). Itly is very frgmented relity when compred with neighbouring countries. While in Frnce, Spin nd Germny there re vrieties tht occupy bout 25% of the vineyrd terroir, in Itly on only 652,000 hectres more thn 350 vrieties of grpevine re cultivted in different wys in reltion to the regionl trditions. The most diffused ntionl red grpe vrieties re: Sngiovese (10%), Montepulcino (4%), Brber (4%), nd Negromro (3%). Interntionl vrieties such s Cbernet Suvignon, Merlot, nd Pinot Noir, nd mny other regionl vrieties re lso cultivted. Concerning Apuli region, the vineyrd re covers bout 85,000 hectres, locted for more thn 90% in the lowlnds nd the reminder in the hills. The 2012 production ws round 8.3 million of quintls (http://www.inumeridelvino.it/2012/08/pugli-produzionedi-vino-e-superfici-vitte-ggiornmento-2011.html), with yield of bout 100 quintls per hectre. The most common forms of frming re the mrquee, the guyot nd the spurred cordon. In Apuli, where bout 82% of the cultivtion of grpe involves red grpe, 3 res cn be distinguished: North-Bri, including the Cpitnt nd the province of Brlett-Andri-Trni, with vrieties such s Uv di Troi, Montepulcino, nd Sngiovese. In this re - 25 -
History, geogrphy, nd economics of grpe wine derived from red berry hlf of the vineyrds of Apuli is concentrted, with production of 5 million tons of grpes (60% of regionl production) nd the highest yields (160 quintls of grpe per hectre); Center, including the province of Bri nd prt of the provinces of Trnto nd Brindisi, with red grpe vrieties such s Primitivo nd Aglinico nd white grpes; Slento, including the province of Lecce nd the remining prts of the provinces of Trnto nd Brindisi, with vrieties such s Negromro, Primitivo, nd Mlvsi Ner. According to preliminry estimtes of the OIV (Interntionl Orgnistion of Vine nd Wine), in the current yer (2014), the world production of wine (excluding juice nd musts) would rech 271 Mhl 2 with decrese of 6% respect to the production of 2013. Frnce is bck in first plce mong wine producers in the world (46.2 Mhl, up 10% compred to 2013) while Itly recorded lower production (44.4 Mhl -15%) compred to 2013), nd Spin bck to level of medium production (37 Mhl) fter record yer (over 45 Mhl in 2013). It should be lso mentioned the strong production growth in Germny (9.7 Mhl, + 16%). The decline in production is mplified in Estern Europen countries: Bulgri, Romni, nd Slovki reported significnt declines in wine production compred to 2013 (respectively -30, -20 nd -16%), due to unfvorble climtic conditions. Only Hungry mintins the level of production of 2013 lso in 2014, with 2.7 Mhl. Elsewhere in the EU, the trends re generlly decresing, s in Croti (-30% /2013 with production slightly less thn 1 Mhl) or, to lesser extent, Portugl nd Greece, with 5.9 Mhl (-6% /2013) nd 2.9 Mhl (-13% /2013), respectively. For the third consecutive yer, the United Sttes showed high production level, nd this in spite of the negtive effects of the erthquke of August nd the dverse climtic conditions occurred in September in Cliforni. The 2014 production ws of pproximtely 22.5 Mhl. In the Southern hemisphere, contrsting trends were observed: Chile, fter two record yers in 2012 nd 2013, seeing significnt decline in its production: 2.8 Mhl (-22% /2013), but it is expected to remin stble t 10 Mhl, while in Argentin the wine production grows slightly: 15.2 Mhl (+ 1% /2013). South Afric would rech wine production of 11.4 Mhl 2 Mhl: milion of hectoliters. - 26 -
History, geogrphy, nd economics of grpe wine derived from red berry (+ 4% compred to 2013). In 2014, New Zelnd would set new record, reching 3.2 Mhl (+ 29% compred to the previous record in 2013: 2.5 Mhl), while in Austrli the production of 2014 seems to mrk slight increse respect to tht of 2013 (12.6 Mhl compred to 12.3 Mhl). Concerning, OIV hven t yet complete informtion on the levels of world wine consumption in 2014, but the vilble evidences indicte consolidtion of the globl consumption of round 243 Mhl (http://www.tetronturle.it/strettmente-tecnico/mondoenoico/20110-cl-l-produzione-vitivinicol-mondile-tutt-colp-dell-europ.htm). - 27 -