苦荞糊和苦荞茶挥发性香气成分分析

采用固相微萃取法（SPME）对苦荞茶和苦荞糊中的挥发性香气成分进行提取,并经气相色谱-质谱联用（GC-MS）技术定性分析。从苦荞茶和苦荞糊中分别检测出30种和41种挥发性香气成分,相同成分有15种,其中含量较高的是烃类、醛类和杂环类,三者在苦荞茶和苦荞糊中含量分别为24.56%、35.04%、18.42%和46.97%、21.22%、7.22%。研究表明,顶空固相微萃取具有快速简便、不使用溶剂和样品检测非破坏性等优点,结合气-质联用技术可以很好的分析苦荞产品中挥发性物质,并说明不同加工工艺制得的苦荞产品其挥发性物质存在一定差异。     

Identification and quantification of aroma compounds of tartary buckwheat (Fagopyrum tataricum Gaertn.) and some of its milling fractions

Tartary buckwheat (Fagopyrum tataricum) seeds have a strong aroma that characteristically differs from the aroma of common buckwheat (Fagopyrum esculentum). Its phytochemical background has only been recently investigated. The aim of this study was to identify and quantify individual compounds responsible for tartary buckwheat aroma. Volatiles from different samples (whole seed, flour, and husks) were extracted with simultaneous extraction and distillation by Likens-Nickerson apparatus and analyzed by GC-MS. A total of 48 compounds were quantified and their odor activity values (OAV) were calculated. OAV of 26 compounds was higher than 10; therefore, they significantly contribute to the overall tartary buckwheat aroma. The compounds with OAV > 500 were: (E,E)-2,4-decadienal, (E)-2-nonenal, 2-phenylethanol, (E,E)-2,4-nonadienal, hexanal, decanal, and nonanal. The most important difference from the aroma of common buckwheat is the absence of salicylaldehyde and presence of naphthalene. Salicylaldehyde could be proposed as a marker to detect contamination/adulteration of tartary buckwheat with common buckwheat. PRACTICAL APPLICATION: Buckwheat is becoming one of important alternative crops. Its products which are rich in proteins, fiber, vitamins, and antioxidants have been associated with healthy nutrition. Although tartary buckwheat is similar to more familiar common buckwheat, their characteristic aromas differ notably. This study expands recent research on aroma of tartary buckwheat tea to seed, flour, and husks, and suggests how products from different species of buckwheat can be distinguished by analysis of aroma compounds.     

SDE/SPME-GC-MS分析苦荞的挥发性香气成分

为了分析不同方法萃取苦荞样品中挥发性物质的差异,采用同时蒸馏萃取法（SDE）和固相微萃取法（SPME）提取苦荞样品中的挥发性成分,用气相色谱-质谱联用（GC-MS）技术定性鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析。同时蒸馏萃取-气谱-质谱法（SDE-GC-MS）分析出23种挥发性成分,固相微萃取-气相色谱-质谱法（SPME-GC-MS）分析出35种挥发性成分,2种方法均提取出酯类、烃类、酮类、醛类和醇类,其中酯类和醛类的含量较多,说明酯类和醛类对苦荞的风味贡献较大。同时蒸馏萃取法适合对高沸点、低挥发性物质进行分离,固相微萃取法具有快速简便、不使用溶剂和样品检测非破坏性等优点,适合易挥发性化合物的检测。将两种提取方法相结合对苦荞挥发性物质提取能得到比较全面的结果。     

膨化苦荞麦茶泡茶特性研究

以高温短时气流膨化苦荞麦茶为原料,以感官评分、黄酮浓度和DPPH清除率为指标,研究其泡茶方法和茶水放置条件对苦荞麦茶水性质的影响。结果表明,料液比、冲泡温度、冲泡时间和冲泡次数对苦荞麦茶水感官品质、黄酮浓度和DPPH抗氧化活性有显著影响,在料液比为1:25,用100℃沸水第1次冲泡15min时茶水的品质最好。同时研究表明,膨化苦荞麦茶可进行多次冲泡,且冲泡8h内茶水中黄酮及其功能性对光照具有良好的稳定性。     

苦荞营养、功能和香气成分的研究进展

苦荞麦是我国传统的杂粮品种之一,有丰富的可开发功能性成分,可加工成多种保健食品和药品,市场发展前景十分广阔。该文对苦荞的营养、功能性成分和挥发性香气成分的研究进展进行综述,并对苦荞食品的深加工进行总结,为今后高营养附加值、优质风味苦荞食品的综合开发利用提供参考。     

熏醅对山西苦荞老陈醋香气成分的影响

熏醅是山西老陈醋的特有工艺,是形成其独特风味的关键步骤.文章采用顶空吹扫捕集和气质联用-嗅闻技术对山西苦荞老陈醋不同熏醅阶段的香气成分进行了分析.熏醅对香气成分的影响研究发现,大多数香气物质在熏醅前3天大幅上升,但从第四天开始迅速下降.香气物质的含量变化主要是由于加热过程中的美拉德反应或strecker降解反应.通过熏醅时间和温度的调整,可以为山西苦荞老陈醋生产过程的控制和熏醅工艺的科学化提供理论依据.     

HS-SPME-GC/MS法分析焙火对铁观音品质及挥发性香气组分的影响

以市售清香型铁观音为原料,通过控制高、中、低温组合方式及烘焙时间对其进行焙火工艺处理。处理后茶样经感官审评及SPME-GC/MS技术分析茶样品质及挥发性香气组分。结果表明:焙火铁观音茶样品质均高于对照茶样,其中c样品质最好。清香型铁观音主要挥发性香气成分:橙花叔醇、吲哚、α-法呢烯、脱氢芳樟醇、反-β-罗勒烯、苯乙酸香叶酯、茉莉内酯、苯乙腈、柠檬烯、苯乙醛等。焙火后带花香/果香类化合物相对含量降低,同时检出一些带烘焙香/火香类物质如:2-乙基-3,5-二甲基吡嗪、2-乙酰基吡咯、1-甲基-1-H-吡咯、2-正戊基呋喃等杂环类化合物。      

固相微萃取(SPME)在茶叶香气分析中的应用

茶叶香气是影响茶叶品质的重要因子之一,其组成复杂且在茶叶中的含量低。固相微萃取作为目前茶叶香气的富集手段,具有操作简便快速等优点,是茶叶香气研究的热点。本文综述了近年来茶叶香气特征和固相微萃取(SPME)技术及其在茶叶香气分析中的应用。      

应用粳米淋饭酒母、苦荞麦粉喂浆开发清爽营养荞麦黄酒工艺

根据苦荞麦的营养成分和特征,结合酶法低温蒸煮新技术,在传统黄酒酿造工艺的基础上,采用粳米饭搭窝、酒药培养糖化制成淋饭酒母,然后在酵母扩配和发酵过程中将粳米喂饭改为苦荞麦粉喂浆,在糖化发酵剂上又融合了白药、红曲、麦曲之长,增加了酒醪中微量成分和代谢产物含量,并在后道工序中引入勾兑调味技术和冷冻吸附工艺,试制开发出具有清醇、爽适、营养、保健的苦荞黄酒。     

云南苦荞茶传统与微波冲泡工艺的响应面优化及比较

研究了传统和微波两种苦荞茶冲泡工艺的响应面优化及比较。固定单次冲泡,传统冲泡考察了茶水比、冲泡温度和冲泡时间三个单因素及交互作用对冲泡液中总黄酮得率的影响,微波冲泡考察了茶水比、微波时间和微波功率三个单因素及交互作用对冲泡液中总黄酮得率的影响,建立了以冲泡液中总黄酮得率为响应值的多元响应数学模型。结果显示,传统冲泡最佳工艺条件为茶水比2.00:100(g:mL)、冲泡温度100℃、冲泡时间45 min,在此条件下,冲泡液中总黄酮得率为0.0350%±0.003%,与多元响应模型理论预测值0.0357%有-0.0007的误差。微波冲泡最佳工艺条件为茶水比2.00:100(g:mL)、微波时间170 s、微波功率400 W,在此条件下,冲泡液中总黄酮得率为0.387%±0.003%,与多元响应模型理论预测值0.393%间有-0.006%的误差。响应值的验证性实验测定值与理论预测值吻合良好,微波冲泡极大地提高了冲泡效率。     

Analysis of characteristic aroma of fungal fermented Fuzhuan brick‐tea by gas chromatography/mass spectrophotometry

Fuzhuan brick‐tea is a popular fermented Chinese dark tea because of its typical fungal aroma. Fungal growth during the production process is the key step in achieving the unique colour, aroma and taste of Fuzhuan brick‐tea. To further understand the generation of the characteristic aroma, changes in the main volatile compounds of Fuzhuan brick‐tea during the fungal growth stage were studied by gas chromatography/mass spectrophotometry. The results showed that the content of volatile compounds, especially aldehyde compounds with stale aroma such as (E)‐2‐pentenal, (E)‐2‐hexenal, 1‐penten‐3‐ol, (E, E)‐2,4‐heptadienal and (E, Z)‐2,4‐heptadienal, increased significantly in fermented tea samples. The concentration of terpene alcohols with flower aroma also increased notably during the fermentation process. The compounds with stale and flower aromas in combination with some volatile components of the raw material contributed to the characteristic ‘fungal/flower’ aroma of Fuzhuan brick‐tea. Microbial metabolism during the fermentation process probably played the key role in the generation of characteristic aromatic compounds of Fuzhuan brick‐tea. Copyright © 2007 Society of Chemical Industry     

添加挤压苦荞粉对纯苦荞挂面加工及面条品质的影响

为提高纯苦荞挂面的加工适应性及面条品质,将挤压处理后的苦荞粉与生苦荞粉混合后制作纯苦荞挂面,将挤压苦荞粉的添加量及和面加水量结合探究其对纯苦荞挂面加工品质及面条品质的影响。通过面带的质构品质、面条的蒸煮及质构特性评价纯苦荞挂面的加工性能和食用品质。结果表明,随着挤压苦荞粉添加量的增加,面带的表面黏附力和抗拉伸力及面条的蒸煮损失率显著(P<0.05)增加;随着和面加水量的增加,面带的表面黏附力显著(P<0.05)增加,抗拉伸力下降,面条的硬度、咀嚼性和蒸煮损失率均显著(P<0.05)增加,当挤压苦荞粉的添加量为30%,加水量为34%时,面带的表面黏附力最低,抗拉伸力适中,蒸煮损失率最小,质构品质较好,综合评价最高。     

苦荞芽苗茶饮料发酵前后营养、风味及抗氧化活性的变化

采用植物乳杆菌发酵苦荞芽苗茶饮料,通过对发酵前后苦荞芽苗茶饮料中芦丁、槲皮素、山奈酚-3-O-芸香糖苷、总黄酮、氨基酸、挥发性化合物、DPPH和ABTS自由基清除率等指标进行测定,研究发酵前后营养、风味及抗氧化活性的变化规律。结果表明,发酵后芦丁含量基本保持不变,槲皮素和山奈酚-3-O-芸香糖苷含量有稍许降低,总黄酮含量从(120.6±1.9)μg/mL微降至(114.6±1.7)μg/mL。苦荞芽苗饮料中包含6种必需氨基酸(EAA)和11种非必需氨基酸(NEAA),发酵后必需氨基酸/总氨基酸(EAA/TAA)为38.32%,EAA/NEAA为62.13%,显著高于发酵前。分离鉴定出8类54种挥发性物质,发酵前含有46种,发酵后含有43种,通过发酵,阈值较低的芳香性风味物质含量明显提升。发酵后DPPH和ABTS自由基清除率均升高,乳酸菌发酵可以提高苦荞芽苗茶饮料的抗氧化活性。     

顶空固相微萃取-气质联用法测定不同陈化时间普洱茶香气成分

目的测定不同陈化时间普洱茶的挥发性组分。方法采用顶空-固相微萃取-气质联用法(SPME-GC/MS)测定18个普洱茶挥发性物质。结果从18个普洱茶中共鉴定出98种挥发性物质,包括14种甲氧基酚类、11种醛类、15种醇类、13种酮类、4种酯类、2种呋喃类、2种含N化合物、35种碳氢化合物及2种其他类物质。陈化时间短(4年)的普洱生茶中醇类(31.01%)和碳氢化合物(22.92%)含量高,甲氧基酚类化合物含量低(1.3%),具有明显的晒青毛茶香气特征。陈化时间长(≥25年)的普洱生茶和普洱熟茶聚成一类,这类普洱陈茶甲氧基酚类化合物含量高(7.52%~39.17%),且不同陈化时间的普洱茶样本之间香气特征相似,仅通过香气无法推断其陈化时间。结论本研究为消费者正确认识和收藏普洱茶提供一定的参考依据。     

Determination of volatile compounds in apple pomace by stir bar sorptive extraction and gas chromatography-mass spectrometry (SBSE-GC-MS)

A method based on stir bar sorptive extraction combined with gas chromatography-mass spectrometry detection (SBSE-GC-MS) has been optimized with the aim of applying it to the analysis of apple pomace. The method allowed the identification of 124 volatile compounds after 3 h of extraction with a precision (RSDs) ranging between 2% (linalool) and 11% (ethyl hexanoate). Its use in analyzing varietal apple pomace revealed the interest of this substrate as regards its content in aromas. From a semi-quantitative point of view, the higher content in aldehydes and esters of the Blanquina variety is worth highlighting, as are the greater concentration of acids in the Clara variety and the higher content of terpenes and norisoprenoides in the Coloradona variety. In contrast, the Ernestina and Perico varieties presented the lowest levels of aromas. PRACTICAL APPLICATION: The analysis of varietal apple pomaces showed the importance of this type of waste in the food industry, both for its content in aromas such as for its use as substrate in biotechnological processes.     

苦荞抗氧化活性研究

苦荞作为一种食药两用的粮食作物,其营养丰富,具有很高的抗氧化活性.近年来,随着我国人民生活水平的提高,其抗氧化活性逐渐受到人们的青睐.文中介绍了苦荞抗氧化活性成分,总结了其抗氧化功能研究现状及开发利用现状.     

Quantification of volatile compounds in Chinese soy sauce aroma type liquor by stir bar sorptive extraction and gas chromatography-mass spectrometry

BACKGROUND: Considering the important of aroma compounds on the quality of baijiu, stir bar sorptive extraction (SBSE) coupled with gas chromatography–mass spectrometry was applied to the aromas analysis of baijiu (Chinese liquor). RESULTS: Based on the results of optimization, a total of 76 volatile compounds were identified from 14 Chinese liquors, including 25 esters, 10 alcohols, 9 aldehydes and ketones, 8 aromatic compounds, 5 furans, 3 nitrogen‐containing compounds, 6 acids, 4 phenols, 3 terpenes, 1 sulfide‐containing compound, 1 lactone, and 1 acetal. By principal component analysis based on quantification results, 14 Chinese liquor samples could be classified into three groups. CONCLUSION: SBSE is a fast, simple, effective, and reliable method for extracting volatile compounds from Chinese liquor. The chemometrics approach revealed that LJ liquor with soy sauce aroma could exhibit more prominent sauce flavor through extending the time of storage, and its peculiar manufacturing practice was responsible for the soy sauce flavor. Copyright © 2011 Society of Chemical Industry     

Comparison of flavonoids profile in sprouts of common buckwheat cultivars and wild tartary buckwheat

In this study, major types of flavonoids in 7‐day sprouts of five common buckwheat cultivars grown in Poland (Hruszowska, Kora, Panda, Luba and Emka) and wild tartary buckwheat were investigated. Results demonstrated that sprouts of common buckwheat cultivars and wild tartary buckwheat contained both known and a newly discovered flavonol: quercetin 3‐O‐galactosyl‐rhamnoside. An exceptionally high content of this flavonoid was found in cotyledons of wild tartary buckwheat (30.79 ± 0.14 mg g^?1 DW), exceeding about 10 times level of rutin (3.16 ± 0.07 mg g^?1 DW). The results are not consistent with the data published so far on the content of flavonoids in sprouts of tartary buckwheat. Higher levels of flavonoids were measured in cotyledons than in hypocotyls with the exception of anthocyanins, which were present in higher amounts in hypocotyls. Cotyledons of common buckwheat sprouts were rich in C‐glycosides of luteolin and apigenin, the total content of which exceeded ca. 5 times the concentration of rutin.     

苦荞饮料的工艺研究

通过正交试验和感官评定的方法，对苦荞饮料的浸提、酶解和调配的工艺条件进行了优化，得出最佳的工艺条件与配比。试验显示：苦荞浸提时调节pH为7，温度55℃，浸提时间90min效果最佳；酶解温度80℃，酶解液pH6，酶解时间45min，加酶量为加水量的1.2%时效果最佳；调配时pH为6，白糖添加量为6%，单甘脂与蔗糖脂肪酸酯（8：1）添加量0.5%，琼脂与海藻酸钠（4：1）添加量0.3%为最佳工艺组成。     

苦荞红曲保健酒的研制

利用苦荞、糯米为原料,经甜酒曲、红曲和酵母糖化发酵,研制出苦荞红曲保健酒。结果表明:最佳生产工艺为苦荞糯米原料配比为1∶1.5、甜酒曲0.6%、红曲12%、酵母1‰、料水比1∶1.5、发酵温度28℃、糖化时间2d、发酵时间6d,所得苦荞红曲保健酒酒精体积分数为16.2%,pH为4.32,总酸含量为6.64g/L,总糖含量为33.4g/L,氨基酸态氮含量为1.36g/L,氨基酸总量为2481.48mg/mL,总黄酮含量为928.18μg/mL,总酚含量为2243.01μg/mL,且口感协调,风味良好。