Identification of aroma-active compounds in ‘wonderful’ pomegranate fruit using solvent-assisted flavour evaporation and headspace solid-phase micro-extraction methods

During the last few years, there has been a tremendous increase in consumption of pomegranate fruit and juice. Nevertheless, very little is yet known regarding the volatile constituents that determine the unique aroma of pomegranate fruit. We extracted aroma volatiles from fresh ‘Wonderful’ pomegranate juice using solvent-assisted flavour evaporation (SAFE) and headspace solid-phase micro-extraction (HS-SPME) methods, and applied gas chromatography–olfactometry (GC–O) (‘sniffing’) combined with gas chromatography–mass spectrometry (GC–MS) analysis, in order to identify volatile aroma-active compounds. In addition, we performed stir bar sorptive extraction (SBSE) of pomegranate aroma volatiles, coupled with GC–MS analysis, in order to assist in identifying aroma-active compounds. Overall, we tentatively identified 23 volatiles in the SAFE and HS-SPME extracts; they belonged to various chemical classes, including aldehydes, terpenes, alcohols, esters, furans and acids. Using the GC–O nasal impact frequency method, we tentatively detected 12 aroma-active peaks and identified the corresponding odourants by GC–MS. The aroma-active compounds of ‘Wonderful’ pomegranates were ethyl-2-methylbutanoate (fruity, apple), hexanal (green), β-pinene (pine, herbal), β-myrecene (woody, musty), cis-3-hexenal (green), limonene (fruity, musty), cis-2-heptenal (soapy, mushroom), cis-3-hexenol (earthy, grassy), 2-ethylhexanol (floral), β-caryophyllene (fruity, musty), 2(5H)-furanone (sweet, fruity) and β-sesquiphellandrene (terpene, almond). Overall, the flavour of ‘Wonderful’ pomegranate fruit derives from a mixture of various ‘green’, ‘woody’, ‘earthy’, ‘fruity’, ‘floral’, ‘sweet’ and ‘musty’ notes.     

The flavor of pomegranate fruit: a review

Despite the increasing commercial importance of pomegranate, especially because of its recently discovered health‐promoting benefits, relatively little is yet known regarding its sensory quality and flavor preferences, or about the biochemical constituents that determine its sensory characteristics. The perceived flavor of pomegranate fruit results from the combination of various taste, aroma and mouthfeel sensations. The taste is governed mainly by the presence of sugars (glucose and fructose) and organic acids (primarily citric and malic acids). The aroma evolves from the presence of dozens of volatiles, including alcohols, aldehydes, ketones, and terpenes, which provide a mixture of various ‘green’, ‘woody’, ‘earthy’, ‘fruity’, ‘floral’, ‘sweet’ and ‘musty’ notes. In addition, the sensory satisfaction during the eating of pomegranate arils is complemented by various mouthfeel sensations, including seed hardness and astringency sensations. In the present review we will describe the sensory quality and flavor preferences of pomegranate fruit, including the genetic diversity in flavor characteristics among distinct varieties. In addition, we will describe the dynamic changes that occur in fruit flavor during fruit ripening and postharvest storage. © 2013 Society of Chemical Industry     

藤茶感官特征定量描述分析与风味轮构建

采用感官定量描述分析法研究藤茶的感官风味特征,并绘制藤茶风味轮。研究结果表明,经培训的评茶小组确定了藤茶的5个外形描述词、5个汤色描述词、7个香气描述词、10个滋味描述词及其定义,之后通过方差分析(P<0.05)结合主成分分析(贡献率>80%),确定所列的27个藤茶感官描述词均可较好评价藤茶样品的感官品质,结合聚类分析进一步得出胶质感、鲜黄、草香、木香、槟榔香、花香、甘甜、回甘、清爽、刺喉感、粗钝感及生津是区分藤茶品质的主要感官特征属性,同时绘制出直观反映藤茶感官特征的风味轮。该研究为了解藤茶的风味品质及开发应用提供参考。     

Comparison of the volatile compositions and flavour properties of cantaloupe,Galia and honeydew muskmelons

Aroma compounds were extracted from three cultivars of muskmelon (Cucumis melo L.) by solid-phase microextraction and analysed by gas chromatography–mass spectrometry. Sulfur-containing esters and compounds containing a straight six-carbon chain were present at high concentrations in cantaloupe melons. Compounds containing a straight nine-carbon chain were at high concentrations in honeydew melons. Methyl esters were present at the highest levels in Galia melons. The sensory properties of the three melons were also compared. Cantaloupe melons were associated with sweet, floral and fruity aromas and a persistent aftertaste. Galia melons possessed the strongest cucumber-like flavours, while cucumber aroma and sweet flavour scored highly in honeydew melons.     

Evaluation of carrot varieties for production of deep fried carrot chips — II. Sensory aspects

Carrot variety had a significant (P ≤ 0.0005) influence on colour, sweet taste, fruity taste, acid taste, bitter taste, earthy taste, juiciness and crispness, while cultivation site (environmental conditions) had a significant (P ≤ 0.0005) influence on colour, sweet taste, bitter taste, earthy taste, aftertaste, juiciness and crispness. Sensory attributes of raw carrots could predict the quality of carrot chips by means of two factors when PLS has been applied. Factor 1 was explained mainly by cultivation site, but also by variety, while factor 2 was explained by variety.     

Identification of aroma‐active compounds in fresh and stored ‘Mor’ mandarins

In this study, gas chromatography–olfactometry (GC‐O) (sniffing) combined with gas chromatography–mass spectrometry (GC‐MS) analysis was applied to identify volatile aroma‐active compounds in homogenised segments of fresh and stored ‘Mor’ mandarins. The GC‐O nasal impact frequency method was used to identify Twenty‐three aroma‐active compounds, of which seventeen odorants were identified by GC‐MS. The aroma of fresh ‘Mor’ mandarins derived from a mixture of eleven odorants that contribute ‘green’ [(E)‐3‐hexenol and hexanal], ‘fresh’ [(E)‐carveol], ‘fruity’ (ethyl 2‐methylbutanoate), ‘citrus’ (limonene), ‘floral’ (linalool), ‘musty’ (β‐myrecene and γ‐terpinene), ‘potato’ (α‐terpinene), ‘mushroom’ (unknown 2) and ‘cabbage’ (α‐cubebene) odours. During postharvest, storage losses were observed in ‘green’ [(E)‐3‐hexenol] and ‘fresh’ [(E)‐carveol] odours, accompanied by increases in ‘fruity’ (ethyl propanoate) and several unpleasant aromas, such as ‘alcohol’ (ethanol), ‘musty’ [α‐pinene, (E)‐2‐nonenal and 1‐terpinen‐4‐ol] and ‘fatty’ (octyl acetate and δ‐cadinene) odours, all of which possibly account for the observed decrease in sensory acceptability after harvest.     

Effects of washing and packing on sensory and chemical parameters in carrots (Daucus carota L)

Carrots washed and packed by hand or machine and stored at 2, 10 or 20 °C in three different package types were analysed for taste, flavour and content of sugars, terpenes, 6‐methoxymellein and ethanol as well as for ethylene, CO₂ and O₂ concentrations in the packages. Carrots washed by machine had increased micro‐organism decay and higher sensory scores for bitter taste, aftertaste, terpene flavour and odour, green odour and earthy flavour. The ability of packages to ventilate was important to avoid anaerobic conditions that caused decreased sucrose content, increased production of ethanol and a higher intensity of ethanol flavour and sickeningly sweet taste. Increasing temperature enhanced the concentration of ethanol, CO₂ and ethylene and decreased the O₂ concentration as well as the content of sucrose and total sugar. High temperature also increased the intensity of ethanol flavour and odour, aftertaste, earthy flavour, terpene flavour and bitter taste. Bitter taste was positively correlated with 6‐methoxymellein level, although this level was below the sensory threshold. Bitter taste, earthy flavour and aftertaste were correlated with total terpenes and several individual terpenes. Carrots washed and packed early in the long‐term storage period (November) were more bitter and had a higher level of 6‐methoxymellein and a higher intensity of terpene flavour and odour, green flavour and earthy flavour than those handled in January or March. Copyright © 2004 Society of Chemical Industry     

Aroma Characteristic and Volatile Profiling of Carrot Varieties and Quantitative Role of Terpenoid Compounds for Carrot Sensory Attributes

The aroma characteristics and volatile profiles of 14 carrot varieties were investigated by sensory evaluations and gas chromatography–mass spectrometry volatile analyses. The sensory map obtained by principal components analysis showed that the sensory attributes comprised 3 categories: sour/green, overall carrot/harsh/ink‐like, and fruity/fresh/sweet. The Kuroda type is characterized by lower intensities of overall carrot/harsh/ink‐like and fruity/fresh/sweet notes. Furthermore, volatile profiling indicated that this type did not have significantly higher amounts of volatiles. Partial least squares regression analysis determined the quantitative contributions to ink‐like, harsh, and fruity carrot aromas; monoterpenes had significant positive correlations with these attributes, while bisabolene isomers had negative correlations. The aroma attribute intensity and contents of volatiles and nutritional compounds are relatively low in the Kuroda type than in other carrot types. This type may be useful for reducing carrot harshness during the development of new carrots with good eating qualities.     

Free and Bound Volatile Chemicals in Mulberry (Morus atropurpurea Roxb.)

Mulberry (Morus atropurpurea Roxb.) is a popular and desirable fruit that is widely cultivated in China. Despite its popularity, the free volatile chemicals and glycosidically bound volatiles (GBVs) of mulberry have been minimally studied. To this end, we have investigated these compounds in 4 mulberry cultivars via solid phase extraction (SPE) and headspace solid phase microextraction with gas chromatography–mass spectrometry (HS‐SPME‐GC‐MS). A total of 55 free volatile chemicals and 57 GBVs were identified and quantified. In 3 of the cultivars (“YFS,” “T10,” and “D10”), the GBVs were found in higher amounts than their free counterparts, corresponding to a ratio of 1.2 to 1.8. The characteristic aromas were determined by their odor activity values (OAVs) and by generating an aroma series (AS). A total of 20 volatile compounds had OAVs ≥ 1.0. In particular, ethyl butanoate, hexanal, (Z)‐3‐hexenal (E)‐2‐hexenal, (E)‐2‐nonenal, and eugenol had relatively high OAVs and were considered to be the key aromas contributing to the mulberry flavor. Consequently, mulberry was characterized by a variety of herbaceous scents having a background of sweet, spicy, fruity, and floral notes. The free volatiles exhibited strong herbaceous notes, whereas the GBVs were responsible for the sweet and spicy qualities of the fruit. Based on our results, 2 cultivars (“YFS” and “D10”) are proposed to be good candidates suitable for the further development of mulberry‐based food products due to their complex and desirable aromas.     

L-阿拉伯糖与氨基酸美拉德反应挥发性风味物质分析

L-阿拉伯糖反应型甜味香精香气柔和、丰富,使用此香精的终端产品有更自然和饱满的香气。用L-阿拉伯糖分别与丙氨酸、甘氨酸、苏氨酸、丝氨酸发生美拉德反应生成反应型甜味香精。采用固相微萃取-气相色谱-质谱联用技术,研究其挥发性风味化合物。结果表明：L-阿拉伯糖分别与4 种氨基酸反应均产生具有烤香和可可香的风味化合物2,5-二甲基吡嗪、2,3,5-三甲基吡嗪和2-乙基-3,5-二甲基吡嗪等。L-阿拉伯糖与苏氨酸发生美拉德反应产生带有青香风味的化合物薄荷酮。L-阿拉伯糖与丙氨酸发生美拉德反应产生带有花果香的风味物质5-茚醇。     

香气活度值法结合PLSR用于梨酒特征香气物质筛选与鉴定

采用固相微萃取-气相色谱-质谱对市售3种梨酒香气物质进行分离鉴定,共检出43种挥发性成分,其中醇类16种、酯类15种、醛类4种、酮类2种、酚类1种、酸类3种和其他化合物2种。结合香气活度值(odor activity value,OAV)和偏最小二乘回归(partial least squares regression,PLSR)确定梨酒特征香气物质并推断其对梨酒香气的贡献程度。OAV结果表明:梨酒特征香气物质主要为异丁醇、1-辛醇、1-壬醇、苯乙醇、丁酸乙酯、3-甲基丁酸乙酯、乙酸异戊酯、己酸乙酯、辛酸乙酯、β-大马士酮、丁香酚。建立6个感官属性(发酵香、酸香、果香、花香、甜香、清香)与43种香气物质的PLSR模型表明,苯甲醇、正丁醇、丁二酸二乙酯的OAV小于1,但对梨酒的香气有贡献,经OAV确定的梨酒特征香气物质与发酵香和甜香属性具有很好的相关性,而在清香、酸香、果香和花香上的相关性不明显。     

白茶贡眉的香气组成与关键呈香成分分析

以全二维气相色谱-飞行时间质谱（two-dimensional gas chromatography-time-of-flight-mass spectrometry,GC×GC-TOFMS）技术结合气相色谱-嗅闻-质谱（gas chromatography-olfactometry-mass spectrometry,GC-O-MS）技术研究贡眉的香气组成及关键呈香成分。结果表明：从贡眉样品中共鉴定出236?种挥发性化合物,以醛类（38.46%）和醇类（25.58%）为主,相对含量较高的有苯甲醛（147.27‰）、反-2-己烯醛（90.14‰）、芳樟醇（79.80‰）、苯乙醇（50.76‰）、2-戊烷基呋喃（46.23‰）、香叶醇（39.06‰）、水杨酸甲酯（37.80‰）、二甲基硫醚（36.69‰）、正癸烷（31.68‰）、正己醛（29.39‰）、苯乙醛（25.06‰）和苯甲醇（22.15‰）等;GC-O-MS检测到26?种香气活性物质,其中鉴定出21?种,包括醇类9?种、醛类5?种、酮类4?种、酯类2?种和芳香烃类化合物1?种;这些香气物质主要呈现清香（或青气）及令人愉悦的花香、果香或甜香。GC×GC-TOFMS和GC-O-MS结果的联合分析表明,高比例的呈现天然清香、花果香或甜香的醇类和醛类香气成分是形成贡眉香气品质的基础。本研究有助于了解贡眉的香气品质化学,为在加工实践中提高贡眉的香气品质提供理论依据。