Characterisation and classification of Spanish Verdejo young white wines by volatile and sensory analysis with chemometric tools

BACKGROUND: Nowadays, Verdejo young wine is exported to many countries all over the world, so it is considered one of the most important Spanish white young wines. In spite of its commercial and historical repercussions, little information is available about the aromatic profile of Spanish Verdejo young wine. The aim of our study was to give further information about this aspect, focusing our research on the characterisation and classification of Verdejo young wine. RESULTS: Aroma of the Verdejo, Sauvignon blanc and barrel‐fermented and barrel‐aged Verdejo wines—all from the D.O. Rueda, Spain—was evaluated using gas chromatographic and sensory analyses. A good relationship was found between the chemical composition and some of the sensory attributes of the wines. The wine samples were correctly classified according to their grape variety and oenological practice showing a 100% of correct classification using chemical or sensory data. CONCLUSIONS: Characterisation and differentiation of Spanish Verdejo wines was achieved, for the first time, showing different groups of Verdejo wines with similar volatile composition and sensory profiles. Copyright © 2009 Society of Chemical Industry     

中外葡萄酒品质安全监测指标比较研究

对中外葡萄酒标准品质安全监测指标进行比较分析。建议尽快建立健全中国葡萄酒行业的质量等级标准、原产地制度，开展针对葡萄酒产品中特征性成分及真假鉴别检测技术研究，完善葡萄酒特征性品质安全指标检测体系，确保葡萄酒产品的品质安全。     

蛇龙珠葡萄（烟台产区）自然发酵醪中选育的酿酒酵母发酵特性研究

对烟台产区蛇龙珠葡萄自然发酵醪中筛选的12株酿酒酵母进行发酵特性研究。首先对发酵终止后的残糖量和酒精体积分数测定,再对部分菌株进行耐酒精、耐酸、耐SO 2和耐高糖能力测定,选取3株发酵性状较好的酿酒酵母用于蛇龙珠干红葡萄酒酿制。结果菌株Y SF4的发酵特性良好,发酵后酒样指标较好,甚至优于商品化酵母,具备工业葡萄酒酿造应用潜力。     

Influence of some oenological practices on the aromatic and sensorial characteristics of white Verdejo wines

Changes in the aromatic composition as well as sensory characteristics in Verdejo white wines were analysed based on two factors: the winemaking methodology and the storing time of wine in bottles. The volatile components were determined by GLC‐MS, and the sensory profile was designed and assessed according to the ISO 11035 standard. The results showed that when wines were made in oak barrels, either completely or partially, which means the wines were in contact with the lees, the levels of 1‐octanol, ethyl heptanoate and ethyl decanoate were significantly affected (P < 0.05); the softness sensation was also influenced (P < 0.05). However, the amount of time the wines were stored in bottles significantly affected (P < 0.05) the levels of 1‐hexanol, ethyl heptanoate, ethyl octanoate, ethyl decanoate, hexyl acetate, isoamyl acetate and isoamyl lactate and also an odour note (tropical fruit). The compounds with higher OAV values belong to the groups of esters and fatty acids. For these reasons, the composition and the quality of the aroma of Verdejo white wines appear to be significantly affected both by use of oak barrels in winemaking and the time the wines are stored in bottles.     

Dynamic Headspace Concentration and Gas Chromatography of Volatile Flavor Components in Peach

Dynamic headspace concentration was used to trap peach flavor volatiles from a promising cultivar under development. Separation and identification of components were by high resolution gas chromatography and mass spectrometry. One hundred ten compounds including alcohols, aldehydes, alkanes, esters, ketones, aromatic hydrocarbons, sulfur-containing compounds and some miscellaneous compounds were positively or tentatively identified. Forty-six compounds were positively identified in peach for the first time.     

Starch,protein, glycoalkaloids,and <Emphasis Type="SmallCaps">l</Emphasis>-ascorbic acid content in tubers of genetically modified potato cv. Irga

Changes in contents of protein, starch, ash, l-ascorbic acid, and glycoalkaloids in tubers of 15 clones of cultivar Irga transformed with viral genome sequences in order to improve their resistance to a necrotic strain of potato virus Y (PVY^N) were investigated. The influence of modification type and year of cultivation on the contents of all chemical compounds examined for particular modified clones appeared to be irregular over the 3-year period of examination, and the clone of the best and stable content of chemical compounds was not found. Stable tendencies in the chemical compounds of tubers composed into groups and subgroups of clones representing the same modification type were not confirmed either. An essential stable decrease in glycoalkaloid content and an increase in starch content (compared with parental cultivar Irga) were found in almost all genetically modified clones. Glycoalkaloid content in green tubers of modified clones was usually (except three clones) higher than this for parental cultivar Irga. Correlation between glycoalkaloid content and tuber size for all, normal and green tubers of selected clones and parental cultivar Irga was examined as well.     

Determination of phenolic compounds of ‘Sikitita’ olive leaves by HPLC-DAD-TOF-MS. Comparison with its parents ‘Arbequina’ and ‘Picual’ olive leaves

‘Sikitita’ is a new olive cultivar developed in Spain by crossing the cultivars ‘Picual’ and ‘Arbequina’. The phenolic fraction of olive leaves (Olea europaea L.), is purported to have good anti-oxidative properties which help to prevent several health problems. To our knowledge, no studies are available on the phenolic fraction of ‘Sikitita’ olive leaves or any other new cultivar developed from breeding. Thus, the identification and quantification of the phenolic fraction of ‘Sikitita’ olive leaves by HPLC-DAD-MS were studied and compared with those of its parent cultivars. The three cultivars were grown under the same agronomic and environmental conditions in the same orchard. The quantification was performed using HPLC-DAD, whereas qualitative data were acquired using HPLC-MS. It was thus possible to identify 30 different compounds, two of which have been tentatively characterized for the first time in olive leaves of Spanish cultivars. Significant differences between cultivars were observed for almost all the compounds. Results for ‘Sikitita’ olive leaves presented a higher degree of similarity with respect to ‘Picual’ than to ‘Arbequina’. Further work will monitor the time course of phenolic compounds over the growth period.     

Volatile profiles of aromatic and non-aromatic rice cultivars using SPME/GC–MS

Rice (Oryza sativa L.) is enjoyed by many people as a staple food because of its flavour and texture. Some cultivars, like scented rice, are preferred over others due to their distinctive aroma and flavour. The volatile profile of rice has been explored by other investigators, some of whom have also determined a corresponding aroma using GC/olfactometry. However, little research has been done to determine if different aromatic rice cultivars produce different flavour volatiles that would make them more desirable than others when cooked. In this study, seven aromatic and two non-aromatic cultivars were examined for their volatile profiles both before and after storage using solid phase microextraction (SPME) fibres in conjunction with gas chromatography/mass spectrometer (GC–MS). Ninety-three volatile compounds were identified, 64 of which had not been previously reported in rice. Differences were found in the volatile compounds of aromatic and non-aromatic rice besides 2-acetyl-1-pyrroline (2-AP). Most of the volatile compounds were present in freshly harvested rice and rice following storage, with very few new compounds being identified only after storage. Dellrose, an aromatic cultivar, and Cocodrie, a non-aromatic cultivar, had the most complex volatile profiles (over 64 volatiles). Sixteen compounds were found only in the aromatic cultivars, and some volatiles were found to be unique to specific aromatic cultivars. However, no distinctive pattern was observed that would identify a cultivar as being derived from Basmati, Khao Dawk Mali 105 (i.e. jasmine), or other sources of aroma. This study showed that there is a great diversity of volatiles in both aromatic and non-aromatic rice cultivars and, with further research, this may lead to a better understanding of the combination of compounds that gives a cultivar a unique flavour.     

Effect of packing materials and storage time on volatile compounds in tea processed from flowers of black elder (<Emphasis Type="Italic">Sambucus nigra</Emphasis> L.)

The effect of cultivar, packaging materials and storage time at 20 °C on volatile compounds in tea processed by gentle air-drying of flowers from the black elder cultivars Sampo, Sambu and Samyl was determined. Elderflower tea samples packed in bags of paper at normal pressure and in bags of plastic and aluminium at 99% vacuum were stored for up to 21 months and investigated for volatile compounds. Volatile compounds emitted from elderflower tea samples were collected by dynamic headspace technique (purge and trap) and analysed by GC–FID and GC–MS. A total of 56 volatile compounds were identified and quantified, including 10 aldehydes, 7 ketones, 21 alcohols, 1 phenol, 3 esters, 4 heterocycles, and 8 hydrocarbons being derivatives of fatty acids, amino acids, shikimic acid and/or of terpenoid origin. Packaging material and storage time had a significant effect on the content of volatile compounds and 15 volatile compounds disappeared partially or completely during processing and/or storage. Tea processed from flowers of the cultivars Sampo and Sambu and packed in plastic and aluminium bags had a satisfactory flavour and content of volatile compounds at least up to 3 months or more after processing, whereas all tea samples processed from Samyl had an unpleasant grassy off-flavour. The content of important volatile compounds with grassy notes such as hexanal, heptanal, and (Z)-3-hexen-l-ol were at the same level in all cultivars. However, the content of important elderflower volatiles with flowery, fruity and/or sweet notes such as linalool, hotrienol, and cis- and trans-rose oxide were significantly lower in Samyl compared to Sampo and Sambu, which to some extent may explain the differences in tea flavour between the stored elderflower tea samples.     

测定稻谷中α-淀粉酶活性的两种方法的比较

采用碘比色法和降落数值法分别测定稻谷中α-淀粉酶活性,对测定结果进行了比较分析。实验结果表明：两种方法都可以测定α-淀粉酶活性,两者的测定结果差异显著,但两者测定结果呈显著直线相关性,说明降落数值的高低能间接的反映α-淀粉酶活性的大小;从变异系数来看,后者的变异程度较低,其精密度较高,前者引起的误差因素较后者多;后者较前者简便快速,重复性好等优点。通过分析研究比较,降落数值法是分析测定大量样品α-淀粉酶活性的最佳方法。     

Biogenic amines in wines: Influence of oenological factors

Biogenic amines formation results from the decarboxylation of the corresponding amino acids by action of microorganisms. The presence of these compounds is considered by some authors a fundamental parameter for detriment of alcoholic beverages. The aim of this work was to assay the effect of some oenological factors (viticulture region, grape variety, anti-fungi treatment of grapes, fermentation activators, malolactic starters and storage on lees) from the point of view of their influence on the biogenic amines content of wines. According to our results, it was possible to show that the viticulture region affects the amounts of amines, since wines of some regions present higher contents of amines than wines from other regions. Grape varieties appear to influence the wine amines content. Commercial malolactic starters, after careful selection, should be added to the vinification process in order to decrease the formation of biogenic amines, since in our assays the wines that were inoculated with starters present lower amounts of biogenic amines. The wine storage on lees contributes for a biogenic amines increase.     

Phenolic Compounds in Fresh and Dried Figs from Cilento (Italy), by Considering Breba Crop and Full Crop,in Comparison to Turkish and Greek Dried Figs

Fresh and dried figs are important components of the Mediterranean diet. In Cilento (Southern Italy), figs belonging to cultivar “Dottato” are used for the production of “PDO Cilento white figs,” as dried figs. In this article, we reported the characterization of the phenolic compounds in 19 fig samples: 9 fresh figs cultivar “Dottato” from Cilento (Italy), 10 dried fig samples from Cilento (2), Turkey (6), and Greece (2). The following phenolic compounds were identified and quantified by high‐performance liquid chromatography (HPLC)/UV‐DAD: chlorogenic acid, protocatechuic acid, vanillic acid, luteolin‐3,7‐di‐O‐glucoside, luteolin 7‐glucoside, apigenin‐7‐O‐rutinoside, rutin, quercetin‐3‐glucoside, and cyanidin‐3‐O‐rutinoside. A discriminative analysis between the peel and pulp of the samples was carried out. The 1st crop (“breba”) and the 2nd one (full crop) from Dottato figs were considered, as well as the effect of fig pollination. The majority of the phenolic compounds were predominant in the fig peel. Significant quantitative differences were found among fresh figs, whereas also some qualitative differences were obtained between fresh and dried figs from the same origin in Dottato cultivar, and among dried figs from different origins. Breba crop resulted richer in phenolics than figs of the 2nd crop. Considering the dried figs, the Turkish ones had the highest concentration in phenolic compounds. Other compounds such as the aminoacids tyrosine and tryptophan were also detected by HPLC‐DAD analysis in Dottato figs, probably due to the similarity of their chemical structure.     

Analytical evaluation of two monovarietal virgin olive oils cultivated in the south of Tunisia: Jemri‐Bouchouka and Chemlali‐Tataouin cultivars

BACKGROUND: The characterisation of virgin olive oils from two Tunisian cultivars, growing in the Tataouin zone, namely Jemri‐Bouchouka, a rare olive cultivar, and Chemlali‐Tataouin, was carried out. Several analytical parameters were evaluated; these include quality index, fatty acids, phenolic, chlorophyll, carotenoid, squalene, α‐tocopherol compositions and oxidative stability. RESULTS: Jemri‐Bouchouka olive oil had the highest value of oleic acid (74.50%) while Chemlali‐Tataouin was characterised by a high percentage of palmitic acid (14.75%), which makes this oil freeze at a low temperature. On the other hand, Jemri‐Bouchouka oil was characterised by a low phenolic and α‐tocopherol content (267.72 mg GAE kg^?1 and 278.34 mg kg^?1, respectively). Ten phenolic compounds were identified. The main phenols found in the two olive oils were oleuropein aglycon and pinoresinol. All phenolic compounds showed significant correlations with oxidative stability. CONCLUSION: The analytical parameters of virgin olive oil that were determined in this study were greatly influenced by cultivar. © 2012 Society of Chemical Industry     

不同加工工艺对‘陕茶1号’绿茶品质的影响

选用‘陕茶1号’春季一芽二叶新梢为原料,分别按照扁形茶、卷曲形茶、针形茶、兰花形茶和炒青工艺加工成绿茶,所制茶样通过感官审评、内含成分分析、香气组分分析和抗氧化能力分析,以确定‘陕茶1号’春季鲜叶原料加工绿茶的最佳工艺。结果表明:兰花形茶各内含成分适中协调,水浸出物含量为46.24%,氨基酸含量最高达4.22%,咖啡碱含量为4.54%,茶多酚含量为21.52%,酚氨比最低,叶绿素含量最高达2.15 mg/g,绿茶主要香气物质含量最高达21.69%,感官品质最佳,其加工工艺是加工‘陕茶1号’春季一芽二叶新梢的最佳工艺;扁形茶感官品质及其主要香气物质含量仅次于兰花形茶,多酚类保留量最高,各内含成分也较协调,且抗氧化能力最强,其加工工艺也适合‘陕茶1号’春季一芽二叶新梢的加工。     

GC-MS与HPLC分析荔枝酒的苦味物质

利用GC-MS分析了荔枝酒中的主体化学成分,各个组分经过质谱图对照分析,鉴定出包括酯、脂肪酸、芳香烃、酮和多种醇类物质,同时利用HPLC分析了酒体中的多种氨基酸.这些物质中,一部分是皮和核中浸提出来的,一部分是通过发酵过程转化而来的,其可使酒体显得更加饱满、柔和.影响荔枝酒口感的主要为后苦味物质,本文对荔枝酒的苦味物质做了分析.     

Wine Analysis and Authenticity Using <Superscript>1</Superscript>H-NMR Metabolomics Data: Application to Chinese Wines

A NMR-based metabolomics method was developed to semiautomatically quantify the main components of wine. The method was applied to discriminate wines from two regions of China, Shanxi and Ningxia, which were produced by 6 wineries and for 6 vintages. Two different cultivars, Cabernet Sauvignon and Beihong, were used for winemaking. The method allowed the quantification of 33 metabolites including sugars, amino acids, organic acids, alcohols, and phenolic compounds. Depending on the compounds, the LOD values were in the range of 0.6 to 116 mg/L. The results showed that NMR-based metabolomics combined with multivariate statistical analysis allowed wine separation as a function of terroir and cultivar. Nevertheless, wine differentiation as a function of wineries and ageing would need to be examined more carefully.     

传统发酵豆豉蛋白质生物学变化与抗氧化能力研究

选取15种具有地区代表性的豆豉,测定总酸含量、水解度、水溶性蛋白含量、酸溶性蛋白含量、褐变指数及总抗氧化能力等指标,利用描述性分析结合主成分分析、聚类分析对样品进行评价。结果表明,15种豆豉样品在质量指标上差异性很大,其中中南地区样品在指标上优于西南地区样品;细菌型豆豉在酸溶性蛋白及水溶性蛋白含量上优于霉菌型豆豉,干豆豉与湿豆豉在质量指数上差别不大。主成分分析及聚类分析表明各质量指标与抗氧化性的关联性从大到小依次为褐变指数＞总酸含量＞水解度＞水溶性蛋白含量＞酸溶性蛋白含量,干豆豉与细菌型豆豉在蛋白水解程度上要优于其他豆豉,而后发酵时间是影响豆豉总抗氧化能力的主要因素。     

Multivariate analysis for the differentiation of sparkling wines elaborated from autochthonous Spanish grape varieties: volatile compounds, amino acids and biogenic amines

The aim of this work was to focus on the study of the volatile composition of white and rosé base wines elaborated from different autochthonous grape varieties in Spain (Verdejo, Viura, Malvasía, Albarín, Godello, Prieto Picudo and Garnacha) and the evolution of the sparkling wines elaborated from them following the “champenoise” method. The amino acids and biogenic amines were also studied. Multivariate analyses (factorial and stepwise discriminant) were carried out to study the influence of these compounds all together. Base and sparkling wines from Albarín, Verdejo, Godello and Prieto Picudo were the richest in most of the volatile compounds analyzed, especially of ethyl esters and alcohol acetates, compounds that contribute to the fruity aroma of wines. During the aging on lees in the bottle of sparkling wines, an increase in branched ethyl esters, ethyl lactate and γ-butyrolactone, and a decrease in terpenes (mainly citronellol and geraniol) were observed. In general, the levels of biogenic amines in all the sparkling wines studied were very low, which does not represent a negative effect on their quality and safety.     

Influence of glucosinolates and a tentative high-molecular detrimental factor on the nutritional value of rapeseed meal

Feeding experiments with mice suggest that high-molecular weight compounds in rapeseed meal without direct relationship to glucosinolates have a detrimental effect on the nutritional value of the meal. This effect is precluded by treatment with ethanol or upon heating. Ethanol extraction improves the nutritional value of the residue as a result of the removal of non-essential nitrogenous compounds. The nutritional value of the seed meal of the cultivar Bronowski was superior to that of the high-glucosinolate meal. A freeze-dried ethanol extract of the high-glucosinolate cultivar Sv Rigo was toxic to mice, especially when fed in combination with myrosinase, in contrast to ethanol extract from the low-glucosinolate cultivar Bronowski. A decrease of the glucosinolate content to a level below that of Bronowski did not effect the growth response of mice.