我国是核桃产量最大的国家,约占世界核桃产量的33%[1]。核桃具有很高的食用和药用价值,核桃仁作为核桃中的主要食用部分,具有较高的营养价值,多项研究表明,定期摄入核桃能够降低胆固醇,预防癌症,降低心血管疾病和神经性疾病发生的风险[2-3]。

核桃油作为人类健康的重要植物油来源之一,是日常生活中一种高端营养的烹调油。核桃油含有较多的不饱和脂肪酸(油酸、亚油酸和亚麻酸等)[4]和多种生物活性物质(如生育酚、角鲨烯、植物甾醇和多酚等)[5],具有抗氧化、抗炎、抗肿瘤、免疫调节、保护心血管、降血脂和降血糖等功效[6]。除了营养方面,风味是影响核桃油消费者接受程度的另外一个重要品质[7-8]。例如己醛呈现油脂味、花生味,阈值较低,是核桃油的关键香气成分之一,但是其来源于亚油酸自氧化形成的13-氢过氧化物,过量的己醛则与油脂氧化形成的异味直接相关[9-10]。

核桃油的营养和风味已成为近来年来业界研究与开发的热点,但是目前还缺少关于核桃油功能特性和风味的整体介绍,尤其是关于核桃油营养品质与挥发性风味之间联系的分析报道较少。本研究在系统总结核桃油的生物活性及其物质基础、挥发性风味构成及其影响因素的基础上,重点剖析了核桃油挥发性风味与生物活性间的关联,旨在解析核桃油营养与美味的科学密码,为核桃油的品质调控及高值化开发利用提供科学依据。

1 核桃油提取方法

提取方法对核桃油的得率及质量等有较大的影响[10]。目前制备核桃油的工艺主要包括传统工艺和新型绿色工艺,见表1[6,11-24]。传统工艺中应用最广泛的是压榨法(冷榨和热榨)和溶剂浸出法。二者相比,压榨法没有溶剂残留问题,但是油脂提取率较低。冷榨能够使核桃油中保留一些天然生物活性成分,同时也能够避免加热带来的油脂、糖类物质的降解,核桃油色泽的改变和核桃粕蛋白质变性等;而热榨能提高出油率,同时使核桃油风味更加丰富[11,25]。

目前已开发的新型绿色工艺主要包括水酶法、超声波辅助提取、超临界流体萃取及亚临界提取等。其中水酶法是在水代法基础上添加生物酶来实现的,绿色环保且安全[18]。同时酶辅助提取可以通过提高核桃油中生育酚含量来提高其抗氧化能力[19]。超声波辅助提取能够增加提取效率、降低溶剂的用量、减少提取时间并降低提取温度,有利于活性物质的保留[16]。超临界流体CO2提取绿色温和、提取率高且价格低廉。有研究表明,CO2萃取和索氏提取(正己烷)的核桃油脂质组成相似,但是超临界CO2提取油中的生育酚含量更高,且CO2萃取的油比正己烷萃取的更清澈[26]。亚临界丁烷萃取同样能实现提取高效、安全,不损伤材料的热敏成分的目标[16,24]。但单一的萃取剂对化合物的选择性较低,所需化合物可能会因萃取剂选择不当而丢失[16]。

在实际生产过程中,由于传统的压榨法操作简单、工艺成熟、成本低而被广泛应用,但是其出油率低,且高温易引起油脂氧化确实不可避免,所以如何不增加成本将一些新型绿色工艺如超声波辅助、微波辅助和酶辅助等技术应用于核桃油的生产是未来重点发展方向。

2 核桃油挥发性风味研究进展

2.1 核桃油挥发性风味物质基础与贡献

根据前人研究,核桃油中的关键风味化合物比较少,李欢康等[13]用不同的提取方法得到核桃油中的挥发性化合物共92种,但是其中的关键香气成分只有4种;Xu等[27]运用开发的整体材料吸附萃取方法得到挥发性化合物77种,其中关键风味化合物有13种。核桃油中的关键挥发性风味化合物主要包括醛、酮、醇、酯、酸和杂环类。

2.1.1 醛类和酮类物质

醛类物质由于其阈值较低且在挥发性成分中占比最大,对核桃油风味贡献最大[28]。相比醛类物质来说,核桃油中的酮类物质较少,可能来源于非端位羟基醇的氧化产物,也可能是酯类物质分解的产物[29],主要有2-辛酮、3-辛烯酮、3,5-辛二烯-2-酮、3-壬烯-2酮、乙偶姻等[13],其中对核桃油风味贡献较大的有呈牛奶香的2-辛酮、呈黄油香的乙偶姻以及呈柑橘香的6-甲基-5-庚烯-2-酮。

2.1.2 醇类物质

醇类物质也是核桃油香气成分的重要组成部分,1-辛烯-3-醇、苯甲醇、己醇和糠醇的含量相对较高[27-28],是核桃油中的关键香气成分[13];己醇呈青草香和甜香[9],产生于核桃油压榨过程中细胞组织破坏时释放出的酶(酰基水解酶、脂氧化酶、氢过氧化物裂解酶、醇乙酰基转移酶等)对亚麻酸以及亚油酸的转化[29],也是核桃油中的主要香气成分[30]。(Z)-5-辛烯-1-醇(甜瓜香)和芳樟醇(柑橘香)具有较高的风味稀释(flavor dilution,FD)因子,对核桃油的风味也具有较大贡献[27]。有研究发现,随着核桃焙烤时间的延长,压榨油中总醇的含量在增加,尤其是1-辛烯-3-醇和戊醇[12],主要原因是焙烤加速了油脂的氧化降解。

2.1.3 杂环类物质

核桃油中的挥发性杂环化合物主要有吡嗪类、呋喃类和吡咯类,其中吡嗪类化合物也是影响核桃油风味的重要部分,由于其阈值较低,具有明显的坚果香,被视为能够改善核桃油风味的组分。核桃油中的呋喃类化合物主要包括2-戊基呋喃、2-辛基呋喃和2-乙酰基呋喃[31],其中2-戊基呋喃产生于亚油酸降解,对核桃油香气贡献较大(FD=81),具有青豆味、黄油味[32]。

2.1.4 酸类物质

核桃油中常见的酸类物质有乙酸、丁酸、己酸、辛酸、壬酸、癸酸等[18,32],主要来源于脂肪酸降解。其中乙酸、戊酸、己酸被鉴定为核桃油中的关键香气化合物,呈现奶酪味和油脂味[13,27]。

2.1.5 酯类物质

酯类化合物的阈值一般较低,大多数都具有果香和甜香[32],但是核桃油中酯类化合物的总含量相对较低,在1.22%～6.99%[12],对核桃油的整体气味有一定的协同作用,关键香气化合物只有乙酸乙酯(果香、甜香)和γ-十二内酯(奶油味、桃子味)。

除此之外,核桃油中的挥发性化合物还有一些烷烃类物质,主要由脂肪酸烷氧自由基均裂产生[9],但是它们的阈值非常高,一般对核桃油的风味没有贡献。

2.2 核桃油挥发性风味化合物的影响因素

据已有的文献,挥发性化合物的含量因核桃产地、核桃品种、榨油工艺及储存期等的不同而不同[13,27,30]。

2.2.1 品种和产地

Bou等[30]对4种引进核桃Franquette、Parisienne、Hartley和Lauzeronne以及2种当地核桃Local pt和Local gd进行挥发性化合物分析发现,戊醛(0.07%～0.12%)、己醛(0.26%～0.80%)、壬醛(0.34%～0.89%)、2-癸烯醛(0.25%～0.68%)和己醇(0.21%～1.58%)的含量因产地和品种而异,同一产地不同品种的Local pt和Local gd,其己醇含量分别为1.58%和0.21%,也存在较大差异[30]。

2.2.2 榨油工艺

榨油工艺对核桃油香气影响的研究主要集中于核桃仁预处理工艺的影响。有研究表明,核桃仁经过烘焙处理之后再榨油,核桃油中醛类和吡嗪类物质含量显著增加,使核桃油更具香脂和烤香的感官特性[12];微波处理具有类似的效果,能通过增加吡嗪类化合物的含量来增加核桃油的烤香特性,从而改善核桃油的风味[33]。吡嗪类化合物来源于美拉德反应,说明烘烤和微波均能促进美拉德反应的发生;醛类物质来源于脂肪酸的氧化降解,随着烘烤时间的增加(0、10、20、30 min)醛类物质含量也增加,核桃油发生了脂质氧化,对于核桃油品质的保持不利,说明只有适度的烘烤处理才有利于核桃油品质的提升。

2.2.3 储存条件

周晔等[34]的研究发现,随着核桃油储藏时间的增加,醛类化合物的含量急剧增加,意味着核桃油发生了氧化劣变。另外,在储存期间,核桃油坚果味和甜味描述词的强度下降,而腐臭和苦味属性的感官评分增加[35]。Ampofo等[36]研究表明,在不同温度(5、23 ℃)下,影响核桃油酸败味的物质不同。其中5 ℃时核桃油的酸败与己醛密切相关,而23 ℃时核桃油的酸败不仅与己醛有关,还与其他氧化挥发物如戊醛和5-庚烯-2-酮的协同活性有关。

3 核桃油生物活性研究进展

风味是核桃油最直接的感官体现,风味的改变意味着核桃油内在物质组成的变化,物质组成的变化进一步决定了核桃油的生物活性与品质,因此通过对生物活性研究进展的总结可以发现风味与生物活性之间的内在联系,对于食品工业生产高品质核桃油具有重要指导意义。

3.1 核桃油的生物活性

核桃油因富含多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)、多酚、生育酚、角鲨烯、植物甾醇和矿物质等生物活性成分而表现出优异的抗炎、抗氧化、抗肿瘤、免疫调节、降血脂和降血糖等功效。

3.1.1 抗炎作用

炎症会引发感染和损伤,是多种生理和病理过程的基础,与多种现代人类疾病相关[37]。多项研究表明核桃油具有显著的抗炎活性,主要表现在降低炎症因子的表达[38],抑制NOD样受体热蛋白结构域相关蛋白3/凋亡相关斑点样蛋白/含半胱氨酸的天冬氨酸蛋白水解酶1(NLRP3/ASC/Caspase-1)炎症通路相关基因和蛋白(NLRP3、ASC、Caspase-1、IL-1β和IL-18)[39]及抑制toll样受体4/髓样分化因子88/核因子κB(TLR4/MyD88/NF-κB)炎症通路相关蛋白(TLR4、MyD88、NF-κB、TNF-α和 IL-6)的表达[40]。这种抗炎活性可能归因于核桃油中丰富的PUFA,Bartoszek等[38]评估了核桃油在葡聚糖硫酸钠(dextran sulfate sodium salt,DSS)诱导的结肠炎小鼠模型中的抗炎作用,发现核桃油能够通过抑制促炎细胞因子的分泌以及上调发炎小鼠结肠中游离脂肪酸受体蛋白FFAR 4的表达起到抗炎作用。

3.1.2 抗氧化作用

核桃油抗氧化活性主要表现在:1)清除自由基。植物油清除自由基能力比较实验发现,核桃油清除自由基的能力要大于芝麻油、亚麻籽油和橄榄油[41]。2)增加抗氧化酶活力。Zhao等[42]研究表明,核桃油可以显著提高小鼠血清、肝脏和大脑中总抗氧化能力(total antioxidant capacity,T-AOC),提高超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力,降低微量丙二醛(malondialdehyde,MDA)含量,同时通过上调血红素氧合酶1(heme oxygenase1,HO-1)和克洛素(klotho)的表达,下调一氧化氮合酶(iNOS)的表达来改善氧化应激引起的病理损伤。3)调节抗氧化相关基因的表达。在核桃油对高碳水化合物(HCD)和高脂肪饮食(HFD)大鼠代谢谱和转录因子的影响研究中发现,补充核桃油降低了NF-κB和还原型辅酶Ⅱ(reduced nicotinamide adenine dinucleotide phosphate,NADPH)氧化酶亚基p22(phox)的水平,而增加了内皮一氧化氮合酶(e-NOS)、Nrf2和sirtuin-1的水平,以此降低氧化应激来减轻HCD和HFD对大鼠的不良影响[43]。核桃油中起主要抗氧化作用的活性成分是多酚和生育酚。其中多酚主要功能是抗氧化[44]。有研究表明,核桃油清除自由基的能力与其多酚含量呈正相关[45]。生育酚具有良好的供氢能力,在不饱和脂质氧化过程中通过断链反应充当潜在的抗氧化剂[46]。

3.1.3 抗肿瘤作用

核桃油抗肿瘤活性主要表现在抑制肿瘤细胞增殖与转移并促进肿瘤细胞凋亡方面,如Batirel等[47]用 0～40 mg/mL的核桃油处理食管癌细胞OE19,发现核桃油能通过减少NF-κB的表达来降低细胞活力,随着核桃油剂量的增加,细胞周期停滞在G0/G1期,细胞坏死增多,转移细胞电位下降。有研究表明,α-亚麻酸和油酸可以协同减少食管腺癌细胞系中的细胞黏附、迁移和集落形成[48]。而且核桃油中褪黑素和PVFA具有抑制环氧合酶(cyclooxygenase,COX)和脂氧合酶(lipoxygenase,LOX)活性的作用,在小鼠乳腺癌模型中表现出了良好的协同抗肿瘤作用[49]。

3.1.4 降血脂作用

核桃油在降血脂方面也具有显著功效,Soussi等[50]在研究核桃油对铅中毒引起的肝损伤大鼠的作用中发现,核桃油能降低甘油三酯(TG)、总胆固醇(T-Ch)、极低密度脂蛋白胆固醇(VLDL-Ch)和低密度脂蛋白胆固醇(LDL-Ch)水平,证实了其降血脂作用。Gao等[51]的研究表明,核桃油可以通过下调HMGCR、SREBP-2和CYP51基因的表达显著降低胆固醇合成,通过上调ABCGI表达增加胆固醇外排,从而显著降低总胆固醇和三酰基甘油,同时证明了核桃油中参与降血脂功效的化合物是总多酚与植物甾醇。另外还有研究报道核桃中的PUFA可激活核受体法尼醇X受体(FXR)的表达,降低SCD1,促进胆固醇外流,并减轻餐后血脂升高[52]。由于心血管疾病多与血脂升高有关,因此核桃油通常还能够通过降血脂功效来预防心血管疾病的发生。有研究报道,核桃油可以降低DSS诱导的结肠炎小鼠主动脉胆固醇酯含量和内皮素1 mRNA水平[53]。由于植物甾醇是环戊烷全氢菲衍生物,由3个环己烷和1个环戊烷环稠合[6]。其结构与胆固醇相似,可以在肠道内与胆固醇竞争,抑制肠道吸收胆固醇,从而降低血浆总胆固醇和低密度脂蛋白(LDL)水平[54-55],因此植物甾醇是核桃油中降血脂及预防心血管疾病的重要物质。另外还有报道证明了PUFA降血脂的重要功能[56]。

3.1.5 降血糖作用

Zibaeenezhad等[57]对100例2型糖尿病患者进行随机对照临床试验,探究食用核桃油对2型糖尿病的影响,发现食用核桃油(15 g/d,持续3个月)可以改善血糖水平,但2型糖尿病患者的体重和血压没有变化。其中有效成分可能是PUFA,因为有研究表明核桃油来源的PUFA能够降低妊娠期糖尿病(GDM)模型大鼠的空腹血糖,并使其血浆胰岛素和肝糖原水平升高[58]。

3.1.6 免疫调节作用

免疫调节是机体识别和排除抗原性异物,维持自身生理动态平衡与相对稳定的重要生理功能。有研究报道,核桃油可以增加小鼠小肠免疫器官(脾脏)指数和分泌型免疫球蛋白A(SIgA)的含量,对改善小鼠免疫功能有显著效果[59]。与此相关的化合物可能是α-亚麻酸,有研究证实n-3多不饱和脂肪酸对于炎症状况以及健康受试者的免疫标志物淋巴细胞增殖、淋巴细胞和单核细胞产生细胞因子均有积极影响,具有免疫调节功能,但是具体机制还不清楚[60]。

3.2 核桃油生物活性的影响因素

核桃油的生物活性主要因其含有的活性成分呈现,这些活性物质又会因核桃品种、产地,核桃油生产工艺以及储存条件的不同而不同。

3.2.1 品种和产地

核桃品种和产地的差异几乎会导致核桃油中所有生物活性物质含量的差异。Amaral等[61]的研究发现,来自葡萄牙的6个核桃品种(Franquette、Marbot、Mayette、Mellanaise、Lara和Parisienne)中的PUFA含量各不相同(70.7%～74.8%),主要是亚油酸;单不饱和脂肪酸(monounsaturated fatty acid,MUFA)的含量为15.8%～19.6%,主要是油酸;同时发现Parisienne和Mellanaise品种核桃油的总植物甾醇和β-谷甾醇含量最低,而Marbot和Lara品种的核桃油含有较高的总甾醇和β-谷甾醇含量。来自塞尔维亚的核桃油中PUFA的含量为67.4%～75.7%,MUFA的含量为15.9%～23.9%[26]。Rabadán等[62]以及Gao等[63]也证明了,核桃油中总多酚和单个酚类化合物的含量也受核桃品种的影响。在对不同国家(中国、法国、匈牙利、印度、意大利、西班牙和美国)的30个核桃样品进行检测后发现,生育酚含量在匈牙利(460～569 mg/kg)和西班牙(429～505 mg/kg)的核桃油中相对较高,中国(309～366 mg/kg)和美国(260～472 mg/kg)的核桃油中相对较低;来自印度的不同品种的核桃油生育酚含量(319～632 mg/kg)差异较大[64]。

3.2.2 核桃采收期

核桃采收期对核桃油中脂肪酸、生育酚以及植物甾醇含量均有显著影响。Matthäus等[65]发现,核桃油中油酸含量随收获时间的不同,从10.51%(第1个采收期)到16.78%(第2个采收期)不等;亚油酸含量为62.35%～67.78%。另外,一般第1个收获阶段得到的核桃油中生育酚含量与总植物甾醇含量均最高[65]。

3.2.3 加工工艺

加工工艺对于核桃油中脂肪酸组成的影响还不明确,有的学者发现提取方法对于核桃油脂肪酸的组成无论是种类或是含量均没有显著性影响[26,66-67]。但是也有研究者指出,烘焙-水酶萃取技术能够提高核桃油中PUFA含量(73.69%)[10],具体影响机制还有待进一步探究。在提取工艺对总酚含量(TPC)的影响研究中发现,冷榨法提取的山核桃油中TPC均显著高于水酶法,可能是由于水酶法提油过程中多酚和黄酮受酸碱、酶解温度、酶解时间的影响而发生降解[68]。但是与冷榨法相比,溶剂提取法得到的核桃油中大部分多酚类化合物的含量更高[66],且要高于烘焙压榨、亚临界丁烷萃取以及超临界二氧化碳萃取[5]。具体使用的溶剂类型也同样影响核桃油的TPC,丙酮提取的核桃油中TPC要高于氯仿-甲醇(体积比2∶1)、正己烷、乙酸乙酯和石油醚[45]。还有研究表明,核桃经烘烤之后再榨油,其中TPC会升高[51,69]。而且烘烤压榨核桃油中的生育酚质量比(411.1 mg/kg)也显著高于冷榨(329.7 mg/kg)、正己烷提取(331.3 mg/kg)、亚临界丁烷萃取(325.4 mg/kg)和超临界CO2萃取(373.7 mg/kg)得到的同类核桃油[51]。另外,关于加工工艺对核桃油中β-谷甾醇含量是否有影响存在一定的争议,有研究表明热榨核桃油中的β-谷甾醇含量得到显著提高(P<0.05)[70],可能是由于高温促进了β-谷甾醇的释放,同时β-谷甾醇在高温条件下具有一定的稳定性;但是也有研究者发现,不同加工方法对核桃油中β-谷甾醇和总植物甾醇含量均没有显著影响[69],产生不同结果的具体原因及机制还有待扩大样本进一步探究。

3.2.4 储存条件

储存条件如氧气、温度、时间等因素均会影响核桃油中抗氧化物质如多酚、生育酚及PUFA的含量从而影响核桃油的氧化稳定性。核桃油在5、10、20 ℃和室温下储存16个月后,过氧化值在室温下比在较低温度下增加得更快,TPC和PUFA含量均略有下降[71]。根据Matthew等[72]的研究,低氧条件下贮存核桃可减少核桃油氧化并减缓总生育酚的降解。

生物活性物质受到核桃品种、产地、采收期、榨油工艺以及储存条件的影响而进一步影响核桃油的生物活性。在实际生产过程中,若想得到营养价值较高的核桃油,应综合考虑多方面因素进行调控。例如:选择采收期较早的来自匈牙利或西班牙的核桃,采用溶剂(丙酮)浸提法进行提取,得到的核桃油抗氧化活性可能更高;经烘烤压榨得到的核桃油可能降血脂活性以及抗氧化活性均较高;低温、低氧条件储存可保持核桃油抗氧化活性。

4 核桃油挥发性风味物质与生物活性之间的关联分析

核桃油的挥发性风味变化和其生物活性呈现均受到原料属性、加工方式和贮运条件等影响,其核心是内在物质组成发生了显著变化,从某种层面上说核桃油挥发性风味变化是评判其生物活性的重要显性指标(图1)。例如,己醛作为核桃油挥发性风味物质最重要的组成部分,来源于亚油酸的氧化降解,呈现典型的油脂味、青草香,是核桃油氧化哈败异味产生的直接原因,所以当核桃油随着储存温度升高或者储存期增加而发生氧化变质的时候,其己醛含量增加,亚油酸含量则减少,意味着核桃油抗氧化、降血脂、抗炎等功效降低。另外一些研究发现,烘焙和微波预处理可以促进美拉德反应过程[12,33],通过增加吡嗪类物质(主要呈坚果香、可可香)来改善核桃油的风味,与此同时增加了抗氧化物质多酚和类黑精的生成,增强了核桃油的氧化稳定性与抗氧化活性,因此核桃油烘烤香的产生可能与其抗氧化活性的增加存在一定的正相关关系。核桃油中芳樟醇等萜烯类化合物不仅是核桃油的关键香气成分,而且有助于提高油脂的抗氧化活性,可以用来替代合成抗氧化剂,预防各种退行性疾病。无论是挥发性香气化合物本身具有生物活性,还是作为一些氧化劣变产物潜在反映了核桃油生物活性的变化,均能侧面反映核桃油的挥发性香气化合物与其生物活性之间存在一定的关联,但是其具体相互作用机制及量效关系还有待进一步研究。

5 结束语

在营养和美味双导向的食品发展趋势下,随着对核桃油生物活性、功能成分、风味构成及其影响因素研究的深入,如何通过选择核桃品种、控制核桃油加工工艺参数及储存条件等因素,实现核桃油风味最佳与营养最大化,是核桃油发展中的重大挑战。本研究综合分析表明,烘焙和压榨可能是生产核桃油的最优策略之一,在保证生产成本低的同时,既能改善核桃油的风味,还能保留核桃油的氧化稳定性与抗氧化活性。若在烘焙和压榨的基础上,加强对核桃油保存时间和温度的控制,可实现风味好、营养高的核桃油生产目标,但是实际加工过程的条件控制与品质监测仍需进一步探索。

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Correlation Analysis Between Flavor Substances and Biological Activity of Walnut Oil

LI Shugang1, HUO Jiaying1,*, ZHOU Qi2, WANG Ping3, LU Chaoqun4, YU Xiongwei5

(1.Engineering Research Center of Bio-Process,Ministry of Education/Key Laboratory for Agricultural Products Processing of Anhui Province/School of Food and Biological Engineering,Hefei University of Technology,Hefei 230601,China; 2.Oil Crops Research Institute,Chinese Academy of Agricultural Sciences,Wuhan 430062,China; 3.School of Food Science and Engineering,Tarim University,Alar 843300,China; 4.Three Squirrels Co. Ltd.,Wuhu 241001,China; 5.Wuhan Xudong Food Co. Ltd.,Wuhan 430000,China)

Abstract：Walnut oil is a good highly processed product of walnut resources in China.As is well known,both the volatile flavor and the biological activity presentation of walnut oil are influenced by its raw material properties,processing methods,and storage and transportation conditions.The core is the significant changes in the internal substance composition.To some extent,the volatile flavor changes of walnut oil are important dominant indicators to evaluate its biological activity.Based on objectively evaluating the main volatile flavor characteristics of walnut oil,the composition of flavor substances in walnut oil was analyzed.Aldehydes,ketones,alcohols,heterocycles,acids,and esters are the key components that give walnut oil a unique flavor.Furthermore,the main biological activities,including anti-inflammatory,antioxidant,anti-tumor,lipid-lowering,hypoglycemic,and immune regulation of walnut oil were introduced.Additionally,the effects of factors such as walnut variety and origin,harvesting period,processing technology,and storage conditions on the flavor compounds and bioactive substances composition of walnut oil were analyzed.Finally,the internal relationship between the volatile flavor of walnut oil and the changes in its biological activity was emphasized.This relationship is not only reflected in the volatile flavor components with biological activity,but also in oxidative products,which indirectly reflect the changes in the biological activity of walnut oil.This paper aimed to analyze the scientific connotation of the correlation between nutrition and flavor of walnut oil,and provide theoretical guidance for the quality control and high-value development and utilization of walnut oil.

Keywords：walnut oil; biological activity; volatile flavor; material composition; influencing factor

中图分类号：TS225.1

文献标志码：A

doi：10.12301/spxb202300528

文章编号：2095-6002(2024)04-0011-11

引用格式：李述刚,霍嘉颖,周琦,等.核桃油风味物质与生物活性关联分析[J].食品科学技术学报,2024,42(4):11-21.

LI Shugang,HUO Jiaying,ZHOU Qi,et al.Correlation analysis between flavor substances and biological activity of walnut oil[J].Journal of Food Science and Technology,2024,42(4):11-21.

收稿日期：2023-08-30

基金项目：安徽省重点研究与开发计划项目(JZ2023AKKG0662);新疆维吾尔自治区重大科技专项(2022A02004);旭东特色坚果高值化利用关键技术与产业化项目(W2023JSKF0310;W2021JSKF0356)。

Foundation：Key Research and Development Program of Anhui Province (JZ2023AKKG0662); Major Science and Technology Projects in Xinjiang Uygur Autonomous Region (2022A02004); Projects for High Value Utilization of Xudong’s Specialty Nuts (W2023JSKF0310; W2021JSKF0356).

第一作者：李述刚,男,教授,博士,主要从事坚果加工和质量控制方面的研究。

*通信作者：霍嘉颖,女,讲师,博士,主要从事坚果加工和质量控制方面的研究。

(责任编辑：张逸群)