葡萄酒的气味是葡萄酒品质的重要组成部分,最大限度地影响着消费者的喜好与选择[1]。在众多葡萄酒气味特征之中,生青味是一类与植物特征密切相关的气味属性。葡萄酒中所表现出的绿叶、青椒、草药等气味特征均属于生青味范畴。适量的生青味可以为葡萄酒带来清新的植物香气,而过量的生青味则会对“花果香”等特征产生掩盖作用,并易造成“蔬菜”和“不成熟”等不良感官体验[2-3]。我国葡萄酒酿造长期存在着不良生青味特征的问题,严重影响了葡萄酒的风味和品质。

阐明生青味产生的物质基础是解决这一问题的首要步骤。为实现对生青味问题产生本质的深入了解,诸多研究对赤霞珠(Cabernet Sauvignon)、霞多丽(Chardonnay)、梅洛(Merlot)等多种生产实践中应用较为广泛的酿酒葡萄品种中生青味物质进行了分析与检测。生产实践与研究中也涌现了基于控制酿酒葡萄成熟度的原理来调整合理采收期等诸多调控措施,并期望达到对不良生青味特征的控制。尽管如此,现阶段降低生青味特征的调控措施仍较为单一且存在诸多弊端。基于对葡萄和葡萄酒中的生青味物质的总结,本研究梳理归纳了现阶段调控葡萄与葡萄酒生青味特征的主要和潜在调控措施,在此基础上,本研究旨在阐明葡萄酒中生青味物质基础和调控手段,以期为此后葡萄及葡萄酒中的生青味特征调控策略的进一步完善和相关研究与应用提供参考。

1 葡萄酒中的生青味物质类别

研究报道的葡萄和葡萄酒中主要生青味物质可分为甲氧基吡嗪类化合物、C6化合物、C9化合物等3大类化合物,见图1。

1.1 甲氧基吡嗪类化合物

甲氧基吡嗪(methoxypyrazine,MP)类化合物是一类广泛存在于青椒、胡萝卜、黄瓜和葡萄等蔬果中的挥发性化合物,对蔬果气味特征具有重要影响。在浓度适宜的情况下,此类物质可为葡萄酒带来清新的感官特点,甚至成为优质品种香气的重要贡献者。然而在浓度过高的情况下,这类物质会造成葡萄酒中一些与“不成熟”、“蔬菜”相关不良气味特征,甚至掩盖其他气味特征,降低葡萄酒的感官质量。MP类化合物中,3-异丁基-2-甲氧基吡嗪(3-isobutyl-2-methoxypyrazine, IBMP)、3-异丙基-2-甲氧基吡嗪(3-isopropyl-2-methoxypyrazine, IPMP)、3-仲丁基-2-甲氧基吡嗪(3-sec-butyl-2-methoxypyrazine, SBMP)、2-甲氧基吡嗪(2-methoxypyrazine, 2-MP)、3-乙基-2-甲氧基吡嗪(3-ethyl-2-methoxy-pyrazine, ETMP)、3-甲基-2-甲氧基吡嗪(3-methyl-2-methoxypyrazine, MEMP)、2,5-二甲基-3-甲氧基吡嗪(2,5-dimethyl-3-methoxypyrazine, DMMP)已在葡萄和葡萄酒中得到检测。

其中,IBMP、IPMP和SBMP是葡萄和葡萄酒中含量最高的3种MP化合物,研究较为广泛。IBMP与甜椒的特征气味密切相关。长相思葡萄酒中,IBMP增强了不愉快的蒸煮蔬菜类香气属性,也对“不成熟水果”和“番茄叶茎”特征的感知起到提升作用[4]。IPMP和SBMP与葡萄酒中生青味等不良特征相关[5]。SBMP和IBMP是黑皮诺(Pinot Noir)葡萄中生青香气的主要贡献物质,但是与C6化合物等物质相比其阈值相对较低[6]。

1.2 C6化合物和C9化合物

不饱和脂肪酸通过脂氧合途径生成的一类分子结构中含有6个或9个碳原子的化合物——C6化合物和C9化合物,因它们与生青味密切相关,被称为绿叶气味组分(green leaf volatiles, GLVs)。C6化合物和C9化合物包含C6/C9醛、醇和酯类物质,它们在葡萄与葡萄酒中广泛存在,对葡萄酒香气特征具有一定影响作用。1-己醇、(Z)-3-己烯醇、(E)-2-己烯醇和(Z)-3-壬烯醇等C6醇类物质与葡萄与葡萄酒中生青特征密切相关。C6化合物对赤霞珠葡萄酒的“生青”和“酸性水果”气味特征贡献较大[7]。双红干红葡萄酒的嗅闻实验证明1-己醇、(Z)-3-己烯醇、(E)-2-己烯醇等C6/C9醇类物质嗅闻过程中主要表现为生青味,具有较高的风味稀释因子(flavor dilution, FD)值[8]。与之类似,基于香气提取物稀释分析发现黑皮诺葡萄C6化合物(Z)-3-己烯醛、(Z)-3-己烯醇和(E)-2-己烯醇被感知为“生青”、“青草”、“青苹果”等,且1-己醛、(Z)-3-己烯醛、(E)-2-己烯醇具有较大的香气贡献度[6]。红葡萄酒中,C9化合物(E)-2-壬烯醛在一定浓度范围下呈现出“湿木头”的香气特征,与绿色橡木桶中陈酿葡萄酒中“木屑样”异味的产生密切相关[9]。此外,(E)-2-壬烯醛在即使其浓度低于香气感知阈值的情况下,也与其他葡萄酒挥发物具有协同作用进而影响葡萄酒的香气[9]。

1.3 其他类化合物

一些硫化物如二甲基硫醚(dimethyl sulfide, DMS)、二甲基二硫醚也会为葡萄酒带来卷心菜、芦笋、草本等生青味特征[10]。DMS是一种含硫挥发性化合物,其浓度升高使歌海娜(Grenache)和西拉(Syrah)葡萄酒整体香气中“黑橄榄”和“灌木丛”等生青属性的强度增加[11]。此外,高DMS水平促进了波尔多红葡萄酒中的“松露”、“灌木丛”等陈酿香气的表达,这也体现了生青特征在适宜的情况下将有助于葡萄酒的风格和典型性[12]。值得一提的是,也有研究发现DMS有助于增强澳大利亚西拉葡萄酒中的深色水果特征,去除DMS的西拉葡萄酒中的生青特征反而有所增加[13]。这可能是由于DMS等含硫化合物与“还原”类香气特征有关,在这种情况下葡萄酒有可能会表现出鸡蛋、植物和卷心菜等主要气味特征,也可能伴有低强度的果味[10]。香气物质对于葡萄酒特征的影响应从整体的观念进行考虑,并结合具体情况分析。不同地区、不同种类的葡萄酒中所得到结论可能存在差异。

2 对葡萄酒中生青味物质的调控措施

生青味特征既可赋予葡萄酒清新独特的风格,又可降低葡萄酒整体香气质量。因此,调控生青味物质对葡萄酒的整体香气风格与质量具有重要意义。葡萄酒中的生青味物质的主要来源是葡萄原料。此外,葡萄酒的酿造、封装与存储过程也会对消费者手中葡萄酒产品中的各类生青味物质的最终含量产生影响。基于此,有效调控葡萄酒生青特征的重要措施可大致分为葡萄原料和葡萄酒两方面。从原料到加工,对生青物质进行全方位、系统性的调控将显著提升调控效果与效率。

2.1 葡萄栽培管理环节

2.1.1 光照调节

光照是植物生长中的重要环境因子,光照可通过影响基因表达进而对挥发性物质组成和其他成分产生重要影响[14]。此外,在葡萄园中对葡萄藤光照进行调节,往往伴随温度等微气候参数的改变。光强调节是影响葡萄挥发性物质组成的重要因素且在田间管理较易实现。一定程度的光照增强有助于葡萄果实生青味物质含量的降低。与荫蔽处果实相比,自然暴露下的葡萄果实酿造的葡萄酒中的IBMP显著较低。葡萄簇的全部遮阴处理使光照强度降低,进而显著提升了葡萄果实中C6化合物的含量并增强了生青味特征[15]。类似地,通过对葡萄藤进行盒式遮光处理,显著提高了葡萄果实中IBMP、IPMP和SBMP的浓度[16]。反射光也是影响葡萄果簇微气候光照的重要因素之一。反射光的调节可通过不同类型的行间覆石来实现。覆盖浅色砾石通过提高葡萄藤反射光强度和局部气温实现了对C6/C9化合物的降低,而深色砾石的覆盖则显著提高了C6/C9化合物的含量[17]。叶幕管理也是调节光照强度的重要措施。摘叶处理有助于提高葡萄果簇暴露阳光强度。摘叶处理显著降低了葡萄和葡萄酒中的甲氧基吡嗪类物质浓度[18]。与之类似的是,对不同大小和可溶性固形物含量的长相思(Sauvignon Blanc)葡萄进行摘叶处理均显著地降低了IBMP的含量,并且不同可溶性固形物含量和浆果直径的影响程度存在差异[19]。葡萄园不同行向将影响葡萄的光照环境。C6/C9化合物含量受行向显著影响,且不同化合物受不同行向下影响情况不同[20]。此外,不同光的类型对葡萄和葡萄酒中挥发性物质也具有不同影响。不同颜色的遮阳网的使用影响了葡萄和葡萄酒中的1-己醇、(E)-2-己烯醇等C6化合物的含量[21]。

2.1.2 水分调节

水分状况往往与葡萄中次级代谢物密切相关。一定程度的水分亏缺可促进葡萄中C6化合物类生青味物质含量降低。对葡萄进行亏缺灌溉水平对梅洛葡萄中的C6化合物[己醛、(E)-2-己烯醛和1-己醇]含量具有显著影响,且显示出了随着灌溉量减少葡萄中C6化合物含量降低的趋势[22]。并且,水分状况较为充足的黑皮诺所酿造的葡萄酒显示出了较强的生青味特征[23]。然而,这一结果也受到年份和葡萄园的影响。生青特征的增强现象可能与水分充足导致C6化合物的含量升高有关。与对照相比,经早期和晚期水分调亏灌溉的丹魄(Tempranillo)葡萄酿造的葡萄酒的C6化合物含量较低,且晚期水分调亏灌溉实现了C6化合物的显著降低[24]。研究发现一般情况下较少灌溉量与较多灌溉量相比,葡萄酒中C6醇类化合物浓度更低,然而相同调亏灌溉处理下两个年份C6化合物的变化具有差异[25]。这可能是由于不同品种对于水分亏缺的响应具有差异,并且不同年份、气候和葡萄园之间与水分的协同作用效果存在差异。甲氧基吡嗪类物质对水分亏缺的响应情况略有差异。经过灌溉处理原料酿造的赤霞珠葡萄酒IBMP和SBMP含量与不灌溉处理相比更高。此外,通过对VvOMT1、VvOMT2、VvOMT3和VvOMT4四个与甲氧基吡嗪相关基因表达的检测,该研究发现VvOMT2在水分亏缺组表达略有差异。同时该研究还发现,带籽浆果最大IBMP峰值与单性结实浆果相比较高。对葡萄进行水分调节除了直接影响了水分外,也间接地通过影响如葡萄的冠层生长等诸多其他因素进一步对生青味物质含量进行调节。尽管如此,水分状况与生青特征之间的密切关联仍不可忽视。一项多变量模型表明,葡萄较低的水分状况是生青香气增强的最有效预测指标[26]。

2.1.3 养分调节

氮素是葡萄所需的重要营养元素,对葡萄的营养与生殖生长平衡起重要作用。与土壤施肥相比,叶面供氮量在较低水平下即可对植物产生显著的影响,且其效果与氮肥性质和用量密切相关。此外,转色期叶面供氮具有调节生青特征的潜力。适宜剂量的转色期叶面供氮有助于降低脂肪醇和醛的含量,有助于减弱由相关物质带来的不良生青气味[27]。苯丙氨酸是较佳的叶面施用氮肥类型,可有效减少C6化合物含量[28]。甲氧基吡嗪类物质方面,叶面施用苯丙氨酸显著降低了葡萄和葡萄酒中IBMP、IPMP和SBMP含量[29]。然而,也有研究认为叶面施用氮肥并非直接改变甲氧基吡嗪类物质和C6化合物的含量来影响葡萄酒中的生青味特征,而是通过影响葡萄遮阴区域间接产生影响[30]。对IBMP代谢相关基因的表达检测结果并未显示叶面施用氮肥直接造成IBMP变化,而是通过改变葡萄藤的活力进而造成葡萄果实的微气候的改变而产生影响[31]。基于此,转色期叶面供氮调控措施可与其他田间措施协同处理,进而对生青味物质起到更好的调控作用。此外,转色期叶面供氮可显著提升葡萄醪酵母可同化氮含量[27]。酵母可同化氮含量可影响乙酸己酯、DMS等挥发性物质含量,并有助于降低葡萄酒中的“生青”、“泥土”等属性强度[32]。需要注意的是,转色期叶面供氮也有可能增强葡萄酒中的生青特征,且氮肥类型不同效果也有所差异[27, 29]。与氮、磷、钾等大量元素相比,葡萄对铁元素需求相对较少。铁元素的缺乏易导致缺铁性黄化病,进而对葡萄的成分造成影响。对不同程度缺铁性黄化病丹魄葡萄酿造的葡萄酒挥发性化合物含量研究结果显示,低单位叶面积叶绿素含量(chlorophyll content per leaf area, Chl)葡萄原料酿造的葡萄酒C6醇类含量低于高Chl葡萄酒[33]。因此,在实际的葡萄栽培实践中应结合现实情况进一步确认合适的处理参数。

2.1.4 葡萄园病虫害管理

葡萄的病害可引起葡萄中部分挥发性物质的升高,进而造成葡萄酒的香气特征改变[34]。葡萄霜霉菌(Plasmopara viticola)引发的褐腐病会引起青绿浆果的萎蔫,而后这些感病浆果将可能经过机械收割与其他浆果一同进行发酵,进而增强所发酵葡萄酒的生青感官特征。由感染葡萄霜霉菌的浆果酿造而成的葡萄酒中的生青味气味主要由IBMP引起,且受褐腐病感染的浆果含有大量IBMP[35]。该研究同时发现,随着酿造基质中病果比例的增加,IBMP的含量也逐渐增加。异色瓢虫(Harmonia axyridis)是葡萄酒中瓢虫污染(lady bug taint, LBT)异味的来源。异色瓢虫混入发酵基质会导致葡萄酒中甜椒、芦笋等生青特征增强,从而对葡萄酒质量造成不利影响[36]。异色瓢虫可释放4种甲氧基吡嗪类化合物——DMMP、IPMP、SBMP和IBMP,其中IPMP是最主要的吡嗪类物质[37]。因此,异色瓢虫的混入提升了葡萄酒中甲氧基吡嗪类物质的含量,这促进了葡萄酒中生青特征增强。

2.1.5 采收期调整

葡萄的成熟伴随着糖类的积累和总酸含量的下降。随着成熟过程的推进,果实挥发性物质产生变化。葡萄采收期的确定不仅需要考虑葡萄的成熟度,更是需要结合最终葡萄酒产品的质量风格和商业定位等因素。由于葡萄原料成熟度可在极大程度上影响果实中生青味物质含量,因此调整采收期成为一种相对普遍的调控措施。甲氧基吡嗪类物质含量在转色期后随着葡萄成熟而持续降低[38]。延迟采收1个月显著降低了赤霞珠葡萄酒的IBMP、C6醇类和乙酸己酯含量[39]。与正常采收相比,延迟采收1周也显著降低弗尔(Fer)葡萄酒中的IBMP含量[40]。与甲氧基吡嗪类物质类似,C6化合物在整个葡萄成熟过程中通常在转色期达到峰值,然后呈现出随着成熟度的提升而下降的趋势[41]。因此,收获成熟度更高的赤霞珠葡萄酒中C6醇的含量较低,但不同年份情况也存在差异[42]。1-己醇、(Z)-3-己烯醇和(E)-2-己烯-1-醇等C6醇浓度在内比奥罗(Nebbiolo)葡萄的成熟过程中也呈现出降低趋势,因而采收期的调整能够实现对这类生青味物质含量的控制[3]。同一气候条件下,(Z)-3-己烯醇是不同采收期西拉葡萄的标志物,体现了采收期和生青味物质含量之间密切相关[43]。与脂氧合酶途径(lipoxygenases pathway, LOX)相关的C6物质,即(Z)-3-己烯醇、(E)-2-己烯醇、1-己醇等在晚期采收的西拉葡萄酿造的葡萄酒中含量更低[44]。与晚采相比,早采收的黑皮诺葡萄与(Z)-3-己烯醇、(E)-2-己烯醇、1-己醇、IBMP和SBMP等生青味化合物关联性更强[6]。尽管不同物质对于不同程度延迟采收的含量变化略有差异,总体而言延迟采收可实现葡萄中不良生青气味特征的降低。

不可忽视的是,采收期的调整会引起酿酒葡萄中糖、酸度失衡,也可提升葡萄遭受病害、降雨和温度变化等风险的概率,进而导致原料品质的下降。延迟采收也可降低葡萄酒的果香和花香,造成葡萄酒香气品质的下降[42]。并且,由于酿酒葡萄生长中挥发性物质的变化时间较短,因此基于挥发性物质来确定采收期进而达到所需目标需要极高的精确度和难度。在综合考虑葡萄果实各项品质的前提下,建立最佳采收期的预测模型等方式有助于确定生青物质含量适宜的采收时间。

2.2 葡萄酒酿造环节

2.2.1 发酵前处理

除了控制原料中生青味物质,葡萄酒采后生产酿造过程中也可实现对生青味物质的干预。紫外线处理是一种较为常见的杀菌技术。对采后葡萄原料进行紫外线(ultraviolet, UV)处理显著降低了葡萄酒中的己醇含量。采后对葡萄的UV-B处理显著降低了白莫斯卡托(Moscato Bianco)葡萄浆果中己醇、(Z)-3-己烯醇和(E)-2-己烯醇的含量[45]。与之类似的是,发酵前对葡萄汁进行UV-C处理降低了C6化合物等物质含量,减弱了发酵所得葡萄酒的生青香气特征[46]。类似地,也有研究发现转色期和转色后去除紫外和红外(infrared, IR)处理可显著提高己醇物质含量[47]。葡萄皮是葡萄酒中挥发性物质的主要来源。葡萄皮中C6醇类物质是所有类别化合物中受烘箱干燥影响最大的物质,经干燥后C6醇类含量下降了约80%,这可能会降低葡萄及后续葡萄酒的生青味特征[48]。类似地,葡萄的预干燥显著降低了卡门(BRS Carmem)和维欧利塔(BRS Violeta)葡萄酒中的C6醇总量[49]。采后葡萄处理对葡萄的生化特性仍具有重要影响,已有研究证明采后葡萄进行干燥处理会影响葡萄中LOX活性,并对应影响C6化合物的含量[50]。因此,葡萄一定程度的脱水处理可能有助于相关生青味物质含量的降低。然而,葡萄藤上的自然脱水却呈现出了不同的趋势。葡萄果实成熟后期的水分流失造成的浆果鲜重不可逆的下降的现象称为季末浆果脱水(late-season berry dehydration,LSD),由这类脱水干瘪葡萄酿制成的葡萄酒中的C6醇类物质更高[51]。发酵前添加吸附剂可有效改变葡萄酒发酵基质成分。葡萄酒发酵前使用硅树脂(一种非极性聚合物吸附剂)处理可实现MP浓度的有效降低[5]。此外,感病葡萄原料和异色瓢虫的掺入也将为发酵基质中带来生青味物质。因此,葡萄原料的健康与清洁性也对发酵所得葡萄酒的生青特征具有影响。

2.2.2 发酵过程处理

浸渍是葡萄酒发酵过程的重要步骤,葡萄果皮与葡萄汁的接触对葡萄酒中的C6化合物具有重要影响作用。冷浸渍显著提升了C6化合物的总量,这一结果可能是与冷浸渍处理导致基质中氧气的溶解量升高进而促进了通过LOX/HPL(lipoxygenase/hydroperoxide lyase)途径C6醛前体的形成[52]。而发酵前的加热浸渍呈现出了相反的趋势,发酵前加热而后浸渍显著降低了C6化合物的总量,这可能与加热影响了脂氧合酶活性有关[52]。此外,压帽过程也被认为可能与葡萄酒中的C6醇类含量有关[49]。发酵前的超声处理降低了桃红葡萄酒的生青特征,然而超声处理组葡萄酒C6醇含量却得到显著提升[53]。此外,C6/C9不饱和醛类生青味物质易受抗氧化剂(如SO2、抗坏血酸、谷胱甘肽)的影响。在葡萄醪中添加SO2发酵所得丹魄葡萄酒与不添加的样品相比C6化合物提升了45%[54]。一部分含6～9个碳的脂肪族不饱和醛,如(E)-2-烯醛类,在氧化条件下生成[55]。有研究对红葡萄酒、白葡萄酒、波特酒等多种葡萄酒进行检测,证实(E)-2-己烯醛和(E)-2-壬烯醛在氧化后的葡萄酒中含量更高[9]。此外,使用氧化的葡萄汁进行发酵的C6醇类物质含量更高,但这一处理也受具体的葡萄品种的影响。因此可以认为,酿造过程中的氧化还原条件变化对这类生青味物质具有较大影响。

采用不同酵母菌株发酵已被证明对葡萄酒香气具有差异性影响[56]。在生青味物质方面,不同商业酵母菌株对IPMP含量的影响各异。该研究也发现不同酵母菌株发酵所得葡萄酒的气味特征不同,部分酵母菌株可减弱葡萄酒中的生青特征。此外,非酿酒酵母的应用也为发酵过程降低生青味物质提供了新的视角和手段。

2.2.3 发酵后处理

酒样的调配是白兰地常使用的方法,目的是使白兰地产品的风味更加协调。对于葡萄酒而言,调配也可作为一种生青特征调整手段。研究发现,对不同品种发酵后的葡萄酒进行调配混合可实现对IBMP含量的调整,且混酿葡萄酒的类型影响大于混酿比例[57]。添加磁性聚合物对生青味物质的吸附也将有助于控制最终葡萄酒产品中的生青物质含量。发酵后添加磁性聚合物也显著降低了赤霞珠葡萄酒74%的初始IBMP浓度,且未对香气产生负面影响[58]。加入氧化铁纳米颗粒的磁性聚合物可去除长相思葡萄酒40%的IBMP[59]。不同塑料聚合物也可实现对葡萄酒中不同甲氧基吡嗪类物质的去除,有机硅和聚乳酸基可生物降解聚合物在8～24 h内对IPMP和IBMP的去除效果最好[60]。

2.3 葡萄酒封装与储存环节

在储存过程中,香气的改变是陈酿的自然现象。尽管甲氧基吡嗪类物质受氧化、存储时光照和温度影响不大,部分C6/C9不饱和醛类生青味物质易受氧化还原条件影响[9, 55]。在葡萄酒封装与储存的过程中,酒塞与酒液接触密切,并且是隔绝空气的重要屏障。酒塞的氧转移率是影响葡萄酒保质期的关键因素,对葡萄酒质量具有重要影响。一方面,酒塞中包含若干生青味物质。软木塞已被证明可将异味传递给葡萄酒,除了熟知的2,4,6-三氯苯甲醚(trichloroanisole, TCA)外,也包括IPMP和IBMP[61]。另一方面,酒塞也可对葡萄酒中的挥发性物质产生吸附。天然软木塞(natural cork)、胶合软木塞(agglomerated cork)和合成塞(synthetic closure)均显示出了对甲氧基吡嗪类物质的吸附能力,且合成塞的吸附能力更强[62]。与天然软木塞和螺旋盖相比,用合成塞封闭的葡萄酒中吡嗪类物质的浓度下降更大。近年来,部分葡萄酒厂在酒塞外设置一层蜡封,这种新晋包装方式也可显著改变酒塞透氧性能,也可能对C6/C9不饱和醛类生青味物质产生影响。(E)-2-己烯醛和(E)-2-壬烯醛在陈酿后的葡萄酒中含量更高,且长时间陈酿的红葡萄酒中的含量要高于短时间陈酿的葡萄酒[9]。陈酿不仅会直接影响挥发性化合物,也会造成以酚类物质为代表的非挥发性化合物的差异。这种非挥发化合物的差异所引起的基质效应的不同也可能进一步影响挥发性化合物的组成。

3 总结与展望

作为葡萄酒质量的“双刃剑”,关于生青味物质及其调控的研究备受关注。以IBMP、IPMP、SBMP为代表的甲氧基吡嗪类物质是引起葡萄酒中青椒、不成熟气味的关键生青味物质。由于生青味物质含量与葡萄成熟程度密切相关,调整采收期、转色期叶面供氮、叶幕管理等葡萄栽培管理措施是甲氧基吡嗪类物质的重要调控手段。与甲氧基吡嗪类物质类似,以C6化合物为代表的绿叶气味组分可通过调整采收期以及控制酿造过程中氧化还原条件实现其含量的调控。此外,一些含硫化合物也对生青特征有所贡献,但不同葡萄品种和地区的情况可能存在差异。除了原料控制外,葡萄酒的酿造处理和封装储存方式也会影响最终生青味物质含量。然而,关注生青味物质的同时,也需明确挥发性物质间复杂相互作用对整体香气特征的影响[63-64]。除挥发性物质外,葡萄酒基质效应也不容忽视。咖啡酸等非挥发性化合物已被证明会影响包括甲氧基吡嗪类物质在内的诸多香气化合物的感知[65]。因此,采用不同措施调控生青味物质的同时,也需明确葡萄酒其他组分产生的基质效应的改变对整体香气的影响。

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Research Progress on Green Off-Flavor Substances of Wine and Their Regulation Measures

SUN Xiangyu1, WANG Yue1, CHENG Guo1, CHENG Guoli2, BAO Shihan3, WANG Jiaqi1, MA Tingting3, FANG Yulin1,*

(1.College of Enology, Northwest A&F University, Yangling 712100, China;2.Baronet Chateau Changyu Babau Co., Ltd., Shihezi 832000, China;3.College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China)

Abstract： The green off-flavor was an important aroma characteristic in wine and played an important role in the wine quality. The widely present green off-flavor substances in grapes and wines could be primarily classified into 3 categories: methoxypyrazines; green leaf volatiles mainly composed of C6/C9 aldehydes, alcohols, and esters generated through the lipoxygenase pathway from unsaturated fatty acids; and other green off-flavor substances represented by certain sulfur compounds. The regulation of green off-flavor substances was of great significance due to their significant impact on the aromatic characteristics of wine. Currently, the regulation could be carried out from grapes and wine making and storage process. Due to the significant relevance between the content of green off-flavor substances in grapes and the factors such as the maturity and environmental parameters, the adjustment of harvesting time, nutrient regulation(foliar nitrogen application during reraison), light exposure management, water control, pest and disease management and other vineyard measures could achieve the effective regulation of the content of the green off-flavor substances during vineyard management. Apart from the grape material, numerous factors in the whole fermentation, packaging and storage process could also influence the green off-flavor substances. However, different ways of regulation could affect other aspects such as flavor compounds, sugar and acid contents of grape and wine quality. While regulating the content of the green off-flavor substances, the aromatic integrity and matrix effect were also important factors that could affect the whole aromatic quality. This work aimed to clarify the substantial basis of the green off-flavor and summarize the major and potential regulation ways to provide reference for further research and industry application.

Keywords： wine grape; wine; green off-flavor; volatile compound; sensory quality

doi：10.12301/spxb202500014

文章编号：2095-6002(2025)04-0015-10

引用格式：孙翔宇,王悦,程果,等.葡萄酒中生青味物质及其调控措施研究进展[J]. 食品科学技术学报,2025,43(4):15-24.

SUN Xiangyu, WANG Yue, CHENG Guo, et al. Research progress on green off-flavor substances of wine and their regulation measures[J]. Journal of Food Science and Technology, 2025,43(4):15-24.

收稿日期： 2025-01-08

基金项目： 陕西省科技计划项目(2024NC-BSLD-01、2024NC-ZDCYL-04-22、2024NC-LSTD-001、2024QCY-KXJ-083);新疆生产建设兵团科技计划项目(2024AB042);宁夏回族自治区重点研发计划项目(2024BBF02003)。

Foundation: Science and Technology Program of Shaanxi (2024NC-BSLD-01, 2024NC-ZDCYL-04-22, 2024NC-LSTD-001, 2024QCY-KXJ-083); Science and Technology Program of the Xinjiang Production and Construction Corps (2024AB042); Key Research and Development Program of Ningxia Hui Autonomous Region (2024BBF02003).

第一作者： 孙翔宇,男,教授,博士,主要从事葡萄与葡萄酒学方面的研究。

*通信作者： 房玉林,男,教授,博士,主要从事葡萄与葡萄酒学方面的研究。

中图分类号： TS261.4

文献标志码： A

(责任编辑：李 宁)