Comparison of volatiles of banana powder dehydrated by vacuum belt drying,freeze-drying and air-drying

Banana puree was dehydrated by using three different drying methods: vacuum belt drying (VBD), freeze-drying (FD) and air-drying (AD) to produce banana powder. Volatiles were extracted from dried banana powder with solid phase micro-extraction (SPME), and separated and identified by gas chromatography–mass spectrometry (GC–MS). SAS (statistical analysis system) was used to evaluate the contribution of the main volatiles. Esters play the most important role in banana powder aroma. The main components detected in banana powder which are responsible for its fruity odor were 3-methylbutanoic acid 3-methylbutyl ester, 3-methylbutyl acetate and butanoic acid 3-methylbutyl ester. Most of the alcohols identified in banana powder were enols and some were of the long chain type. Eugenol and elemicin which give the product its typical mellow aromas were also identified. Alkyls, alkene and alkyne constituted the minor components in banana powder. Basing on the principal component analysis of statistical analysis system, it can be inferred that the preferred method for producing banana powder with the optimum aroma is FD, followed by VBD and then AD.     

混和发酵果酒香气物质成分分析

采用气相色谱-质谱联用对菠萝及菠萝、芒果和香蕉混合发酵果酒的香气成分进行了测定。结果表明,与菠萝果酒相比,混酿果酒含有更多中、高沸点的香气物质,产品的果香浓郁,留香持久。     

固相微萃取--气质色谱法测定玫瑰香葡萄酒中的香气成分

用固相微萃取蜒气质色谱法测定了玫瑰香葡萄酒中的挥发性香气物质,检出12个醇类化合物、16个酯类化合物、9个萜类化合物及少量醛类化合物,及其赋予的香气特征.     

Aroma profile of a collection of near-isogenic lines of melon (Cucumis melo L.)

This paper characterizes the aroma volatile profile found in a collection of near-isogenic lines (NILs) of melon (Cucumis melo L.) obtained by solid-phase microextraction and analyzed by gas chromatography–mass spectrometry. The collection was built with introgressions of an exotic accession (PI 161375) into the parental line ‘Piel de sapo’ (PS) and was useful for mapping quantitative trait loci (QTLs) associated with melon flesh aroma. The aroma profile was composed of 24 compounds detected in PS or the NILs: three esters, six aldehydes, three alkanes, three aromatic hydrocarbons, two terpenes, two ketones, one alcohol, one sulphur-derived compound, one cyclic branched alkene, one naphthalene and one ether. Hexanal showed the highest relative concentration in the collection, followed by camphor and methanethiolate with no difference between PS and the NILs. These results allowed us to map four QTLs in linkage groups IV, VIII and XI associated with the formation of 3-hydroxy-2,4,4-trimethylpentyl 2-methylpropanoate, octanal and (Z,Z)-3,6-nonadienal.     

Aroma investigation of unifloral Greek citrus honey using solid-phase microextraction coupled to gas chromatographic–mass spectrometric analysis

The aroma of Greek citrus honey was investigated by means of SPME–GC/MS analysis. A total of 61 compounds could be identified, with lilac aldehydes predominating the extract. These compounds can be considered the most powerful markers for citrus honey. Additionally, the two isomeric dehydroxy linaloxides, lavender lactone, dill ether, the four isomers of 1-p-menthen-9-al, methyl anthranilate and nerolidol could aid the botanical discrimination. Of the compounds identified, five are reported as honey constituents for the first time, that is trans- and cis-dehydroxy linaloxides, 1,8-menthadien-4-ol, limonene-10-ol and methyl N-methylanthranilate.     

Retention of selected aroma compounds by gelatine matrices

The retention of various aroma compounds (linalool, limonene, ethyl butyrate, butyl acetate, isobutyl acetate, pentyl acetate, isopentyl acetate, hexyl acetate) by gelatine gels (2.5, 5, 10 and 20 wt%) was investigated by Static Headspace Gas Chromatography. Prior to analysis the samples were left to equilibrate at 37 °C for 24 h. The selected volatiles differed in their hydrophobicity and structure. One of the major conclusions was that increased hydrophobicity, in volatiles within the same homologous series, resulted in increased release. Branched volatiles gave greater partition coefficient values than their linear counterparts. When volatiles without the same functional group were compared, no correlation between hydrophobicity and retention was observed. The different mechanical properties of the matrix, as a result of different protein concentration, also affected the aroma retention. The effect of equilibration temperature on partition coefficients was also studied. Increased temperature resulted in higher partition coefficient values, probably due to the increased volatility of the aroma compound. Both positive and negative percentage of retention values were calculated suggesting varying protein-volatile interactions.     

中国白酒香型的化学模式识别(Ⅲ)——判别分析

以每一酒样的乙酸乙酯、己酸乙酯等１７种香味成分的气相色谱、气质联用定性定量分析数据和评价结果为指标,用贝叶斯判别法对３４个浓香、清香、酱香型样本进行了判别分析。并用１２个待判样本检验了判别方程的有效性。从统计学的观点来看,所选的判别分析法可靠、分析结果令人满意。     

中国白酒香型的化学模式识别(Ⅱ)--聚类分析

以46种白酒为样本,以每个样本的乙酸乙酯、己酸乙酯等17种香味成分的气相色谱、气质联用定性定量分析数据和感官评价结果为指标,用聚类分析研究了白酒香型数据。从统计学的观点来看,本文所选聚类方法可行,所得分析结果理想。     

中华酒道——白酒酒香之道

中华酒道是博大精深中华文明的重要标志之一,是中华传统文化重要组成部分。文章论述了中华酒道酒之风味篇酒香之道。     

The nutrients of exotic mushrooms (Lentinula edodes and Pleurotus species) and an estimated approach to the volatile compounds

Texture, nutritive values and volatile compounds of Lentinula edodes, Pleurotus ostraetus and Pleroutus sajor-caju mushrooms were determined. The volatiles have been found out with an estimation approach by carrying out gas chromatography and mass spectrophotometer (GS–MS) Library Catalogue comparison. Neither regular increase nor decreases were observed for the values of texture, moisture, ash and protein values of L. eddoes. While a decrease, negative correlation was seen in values of vitamin C, folic acid and niacin values from the first flush to fourth flush periods, there was no correlation in the values of riboflavin and thiamin. Average mineral values of Shiitake (mg/kg wet basis) were: Zn, 10.18; Fe, 5.69; P, 998.47; Ca, 64.55; Mg, 191.89; K, 2347.33; Na, 622.40, proximate composition, vitamin C, folic acid, niacin, B1, B2 were determined in Pleurotus mushrooms. These mushrooms can contribute nutrition for protein and vitamin daily requirements. The mean mineral values of Pleroutus species (mg/kg, wb) were: Zn, 11.18–9.31; Fe, 14.80–7.94; P, 998.47–716.31; Ca, 81.16–23.66; K, 2225.00–2687.00; Na, 750.77–773.67, respectively. The volatile compounds, typical esters which are found in the mushrooms, hydrocarbons and fatty acids derivatives were determined with estimated approach by comparing library catalog of (GS–MS).     

Effect of the matrix volatile composition in the headspace solid-phase microextraction analysis of extra virgin olive oil

The effectiveness of headspace solid-phase microextraction (HS-SPME) for the quantitative analysis of extra virgin olive oil volatiles was investigated on 44 standard compounds, using an adsorbent polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber. The method’s sensitivity was satisfactory, as was its repeatability. However, when the extraction was carried out on mixtures containing all the standard analytes, phenomena of coating saturation and competition between components caused losses in linearity at lower levels of concentration, thus distorting the quantitative evaluation. Coating saturation or displacement between components was also found to be responsible for the bias in the quantitative determinations when extra virgin olive oil samples were analysed. These limitations were overcome by diluting the oil at concentrations not exceeding the total capacity of the fiber coating and until the quantity of displacing compounds was reduced to sufficiently low levels.     

醇化过程中白肋烟香味成分含量的变化

对醇化过程中白肋烟香味成分含量的变化进行了研究。结果表明 ,在醇化过程中白肋烟香味成分含量发生了明显变化。在所测定的 17种中性香味成分中 ,许多中性香味成分含量在醇化过程中呈明显增加趋势 ,增加幅度较大的成分有糠醛、糠醇、苯甲醛、苯乙醇、氧化异佛尔酮、巨豆三烯酮和金合欢基丙酮等。在所测定的 12种碱性香味成分中 ,有吡啶、2 ,3-二甲基吡嗪、2 ,5 -二甲基吡嗪、2 ,3,5 -三甲基吡嗪、四甲基吡嗪、2 -乙酰基吡啶等 6种重要碱性香气成分含量有明显增加 ,但碱性成分总含量在醇化过程中呈大幅下降趋势。     

加料前后烟草中游离及糖苷结合态香味成分的分析研究

对加料前后烟草中游离及糖苷结合态香味成分进行了分析研究。烟末经乙醚萃取和同时蒸馏萃取(SDE)分离得游离香味成分。糖苷成分用甲醇萃取,采用非离子型大孔树脂(AB8,相当于AmberliteXAD-2)吸附,然后用不同选择性溶剂洗脱和溶剂萃取,使糖苷与可溶性糖、氨基酸、有机酸、游离香味成分分离。糖苷集份在弱酸条件下(pH2.5)SDE水解,同时萃取出精苷结合态香味成分。采用毛细管气相色谱(HRcGC)和气相色谱/质谱联用(GC/MS)技术鉴定了25种游离及糖苷结合态香味成分。对加料前后的烟草样品进行了对比分析,结果发现:在所分析的烟草样品中,糠醇、苯乙醇、茄酮、香叶基丙酮、β-紫罗兰酮等成分,游离态含量高于结合态的含量;苯酚、香草醛、巨豆三烯酮等成分,游离态和结合态的含量相当;糠醛、苯甲醛、苯乙酮、异佛尔酮、氧化异佛尔酮、4-乙烯基愈创木酚、大马酮、二氢大马酮等成分,结合态的含量高于游离态含量。加料前后的烟草样品相比,加料后烟草中游离态香味成分呈减少趋势,但结合态含量呈增加趋势。      

Effect of the solute on the development of compositional profiles in osmotic dehydrated apple slices

Apple (cv. Granny Smith) slices, 30-mm thick, were osmotically dehydrated for 9 h at 30 °C using glucose, sucrose and trehalose solutions with the same water activity (a_w = 0.96). After OD treatment, water and solute content were analysed in 1.5-mm thick serial disks of the apple slices to determine the effect of osmotic dehydration on the compositional profiles. Diffusional and “Advancing Disturbance Front” (ADF) models were applied to the experimental data, both showing a good fit. Changes in the compositional profiles of osmotically dehydrated slices were also analysed throughout storage time. For this purpose, the 30-mm thick dehydrated slices were kept at 10 °C for 7 days in hermetic plastic bags and compositional profiles were analysed after 1, 2, 3 and 7 days and modelled using Fermi's equation. Throughout storage, the profiles became flatter due to the counter-current migration of water and solutes associated to the concentration gradients. Mass transfer rate during dehydration was faster when sucrose or glucose was used, but trehalose implied an increase in the mass transfer resistance of the tissue. This behaviour was also observed in the mass transfer processes during storage. This effect was attributed to the changes induced by trehalose in the permeability of cell membranes through component interactions.     

加工技术对苦瓜脱水过程中VC含量的影响

研究不同加工技术对苦瓜脱水过程中VC含量的影响.结果表明:经蒸气热烫处理的苦瓜VC含量明显高于热水热烫后的苦瓜,80 ℃蒸气热烫处理2 min时苦瓜中VC含量最高;蒸气热烫后再经冰水冷却的苦瓜VC含量高于自然冷却后的含量;苦瓜经真空冷冻干燥后,其形态、色泽及VC含量均优于用微波、热风干燥的苦瓜.试验得出的最佳工艺为:80 ℃蒸气热烫2 min后,再用冰水冷却,经-25 ℃冷冻6 h,真空干燥后苦瓜中还原型VC为35.2 mg/100 g,氧化型VC为86.15 mg/100 g,总VC为121.35 mg/100 g.     

白肋烟重要香味物质组成的研究

采用同时蒸馏萃取、气相色谱和气质谱联用法对国产 (湖北鹤峰、重庆奉节 )和进口 (巴西、津巴布韦和马拉维 )白肋烟中的酸性、碱性和中性香味物质进行了分析 ,共鉴定出 2 0 0种香味物质。文献检索表明 ,其中有 30种成分为烟草中尚未报道的化合物。采用内标法对白肋烟中重要的 2 6种碱性、39种中性和 15种酸性香味物质的含量 ,以及酸性、碱性和中性香味物质的总量进行了定量测定。分析结果表明 :在所分析的白肋烟样品中 ,(1)国内外白肋烟均含有相同种类数的香味物质 ,其不同点在于 :①国产白肋烟烟叶的酸性成分总量低于津巴布韦和马拉维白肋烟 ,而高于巴西白肋烟 ;②国产白肋烟的中性香味成分总量 (不计新植二烯 )高于津巴布韦和巴西白肋烟 ,略低于马拉维白肋烟 ;③国产白肋烟中的新植二烯含量明显高于国外白肋烟 ;④湖北白肋烟的碱性香味成分总量与巴西和津巴布韦白肋烟的接近 ,略高于马拉维白肋烟 ;⑤国产白肋烟中的杂环化合物 (吡啶、吡嗪和吡咯类 )和生物碱类化合物含量低于巴西和津巴布韦白肋烟 ;(2 )国内 2个主产区白肋烟香味物质的含量在酸、碱、中 3个集分中的差异比较突出 ,即除了湖北上部白肋烟酸性成分的总量低于重庆上部白肋烟的以外 ,湖北上部、中部和下部白肋烟中性和碱性香味成分 ,以及中     

Volatile compounds of virgin olive oil obtained from Italian cultivars grown in Calabria.: Effect of processing methods,cultivar, stone removal,and antracnose attack

Calabria is an important olive-growing area of the Mediterranean producing high quality virgin olive oil from a wide variety of cultivars. The present work analyses the influence of cultivars, processing methods, anthracnose attack and stone removal on volatile compounds. Solid phase microextraction (SPME) was used because is easy to use, cheap and rapid. The volatile compound content of different cultivars is influenced by the enzymes involved in the lipoxygenase pathway. The effect of anthracnose attacks increases the content of aldehydes such as heptaldehyde, octyl aldehyde and nonanal. Oil obtained from destoned olives shows a greater quantity of C5 and C6 volatile compounds compared to oil obtained from unstoned olives. Oil obtained in the laboratory has a higher volatile compound content compared to that obtained commercially. Limited scale oil production have a lower oil yields but enables greater content of compounds in the headspace in the final product and thus may be a valid alternative for small agricultural businesses.     

Aroma release of a model wine solution as influenced by the presence of non-volatile components. Effect of commercial tannin extracts, polysaccharides and artificial saliva

The effect of commercial tannin extracts, extracted either from grape seeds or grape skins, a natural wine polysaccharide extract, pectin and arabinogalactan on the headspace release of selected aroma compounds from a “model wine” solution was investigated. Changes in the volatility of the aroma compounds were studied using headspace solid-phase microextraction combined with GC/FID. The performance of four commercially available fibre coatings was checked and the 50/30 ??m DVB/CAR/PDMS one was proved to be the most effective. A short sampling time (1 min) was used to determine the “true” headspace concentration at equilibrium between the headspace and the sample. In general, the volatility of the studied aroma compounds appeared to be correlated to increasing tannin levels as well as to their origin. The volatility of esters was generally increased upon tannin addition at low concentrations, while at higher addition levels the two extracts exhibited dissimilar behaviour attributed to their different composition. Both arabinogalactan and pectin addition at low concentrations increased the volatility of the studied aroma compounds, while at higher concentrations pectin exhibited a different behaviour by salting out hydrophobic compounds in the vapour phase. In addition, grape skin and seed tannin extracts in admixture with polysaccharides either prevented the macromolecular chains to associate with volatile molecules or led to additional flavour retention depending on the aroma compound and the addition level. Saliva addition enhanced the volatility of the most hydrophobic compounds whereas the hydrophilic compounds were retained into the matrix.     

全梨汁酿制干酒工艺研究

介绍了以梨为原料发酵干梨酒的工艺,通过在梨汁中添加维生素C,抑制了梨汁的褐变、保持了原果香.成品酒风格独特,营养丰富,具有一定保健功效.     

Agri土壤调理剂用量对烟叶香气质量的影响

通过田间试验研究了Agri土壤调理剂不同用量(0,3.75,7.50,11.25,15.00 kg/hm2)对烟叶香味物质、感官质量和经济性状的影响。结果表明:随土壤调理剂用量的增加,烟叶美拉德反应产物、类胡萝卜素降解产物、芳香族氨基酸降解产物、总香味物质含量和香气质量提高,烟叶产量增加,烟叶产值、均价和上等烟比例先提高再降低。土壤调理剂用量11.25 kg/hm2时烟叶美拉德反应产物、类胡萝卜素降解产物、芳香族氨基酸降解产物、总香味物质含量、香气质量得分和产量较高,产值、均价和上等烟比例最高。