Flavour profile of capers (Capparis spinosa L.) from the Eolian Archipelago by HS-SPME/GC–MS

This paper presents the first investigation of the flavour profile of capers (Capparis spinosa L.) from the Eolian Archipelago. In all, 145 volatile compounds were identified and quantified in capers, by HS-SPME/GC–MS analysis. Aldehydes (22.2%) and esters (21%) were the most abundant chemical classes; five sesquiterpenes and ten monoterpenes were identified for the first time; among sulphur compounds (8.42%), methyl-isothiocyanate was the major one, followed by benzyl-isothiocyanate. The application of this solvent-free extraction technique combined with the GC–MS analysis, showed its potential as a simple routine method for analyzing food flavour.     

顶空-固相微萃取两种传统面酱挥发性成分的气相色谱-质谱联用分析

采用顶空固相微萃取和气-质联用(GC-MS)技术,对2种传统面酱(M1和M2)中的挥发性成分进行提取、分析。从M1中鉴定出53种挥发性化合物,占色谱流出峰总面积的77.408%,包括醛类6种,酯类5种,酸类14种,烃类2种,醇类2种,杂环类化合物12种,酮类2种,其他化合物10种。从M2中鉴定出48种挥发性化合物,占色谱流出峰总面积的64.455%,包括醛类6种,酯类8种,酸类6种,烃类4种,醇类5种,杂环类化合物9种,酮类4种,其他化合物6种。     

Volatile compounds evolution of three table grapes with different flavour during and after maturation

Volatile compounds of three different flavour table-grapes, ‘Jingxiu’, ‘Bimeijia’ and ‘Jingya’, were investigated during and after maturation using SPME/GC–MS. All the alcohols and carbonyls, along with most of the C₆ compounds and terpenoids, were evident before veraison, while most of the esters were detected at or after veraison. C₆ compounds increased in the early period of maturation, and then decreased. Most alcohols and carbonyls tended to continuously decrease during ripening. Except for geraniol, terpenoids increased until maturation, then decreased. Some esters continued to increase after maturation. Principal component analysis showed that terpenoids and esters were the characteristic volatiles of ripe ‘Bimeijia’ and ‘Jingya’ grapes, respectively. ‘Bimeijia’ had the highest terpenoid content at maturity, while ‘Jingya’ continued to accumulate some esters after maturation. To achieve berries of full-bodied aroma, ‘Bimeijia’ should be harvested at maturity and ‘Jingya’ should have a delayed harvest. For the neutral grape ‘Jingxiu’, delayed harvest is recommended to reduce the ‘green’ odour.     

Influence of polyols and bulking agents on flavour release from low-viscosity solutions

The release of four volatile flavour compounds (cis-3-hexen-1-ol, benzaldehyde, ethyl butanoate and butyl isovalerate) from pure water and various low-viscosity aqueous solutions (sucrose, maltitol, erythritol, polydextrose and oligofructose, each at 20% (w/w)) was investigated. Dynamic headspace concentrations of the flavour compounds at thermodynamic equilibrium were monitored by proton-transfer-reaction mass spectrometry (PTR-MS). The rheological properties of the solutions were characterised by their viscosity. Flavour release from pure water increased with increasing hydrophobicity and volatility of the flavour compounds. The highly volatile compounds were retained more extensively in the presence of sucrose, polyols and bulking agents, compared to in pure water, whereas an increase in the release of the less volatile cis-3-hexen-1-ol was observed. All aqueous solutions had similar viscosities, although bulking agent solutions tended to have higher viscosities than polyol solutions of the same concentration. A correlation between viscosity and flavour release in the low-viscosity solutions was not evident.     

Influence of chewing gum packaging design on consumer expectation and willingness to buy. An analysis of functional, sensory and experience attributes

This paper studies the influence of two design variables of chewing gum packaging, those of colour and format, on consumer expectations of specific product attributes and willingness to buy. Some 390 consumers participated in this investigation, evaluating a total of 30 functional, sensory and experience attributes for nine different packaging designs. The results demonstrate that packaging format influences expectations of functional attributes, sensory attributes of texture and experience attributes, while colour influences expectations of sensory attributes of taste and flavour and experience attributes. The study also reveals that willingness to buy is more closely related to the colour of the packaging than to its format.     

SDE法和HS-SPME法萃取自然腌冬瓜挥发性物质的比较

经自然腌制的冬瓜样品分别通过同时蒸馏萃取（SDE）和顶空固相微萃取（HS-SPME）提取挥发性风味物质,并用气相色谱-质谱联用仪（GC-MS）进行鉴定。结果表明,两种萃取方法共检出61种挥发性物质,其中SDE方法检出21种挥发性物质,HS-SPME方法检出42种挥发性物质,SDE法检出的主要有棕榈酸、邻苯二甲酸二异丁酯和二十二烷等高沸点挥发性物质,而HS-SPME法检出的主要有乙酸、乙醇、丙酮和乙酸乙酯等低沸点挥发性物质;相对标准偏差（RSD）结果表明HS-SPME法重复性比SDE好。综合结果采用HS-SPME法萃取腌冬瓜样品挥发性物质优于SDE方法,而2种方法的综合使用能更全面地反映腌冬瓜样品的风味构成。      

Changes of volatile compounds in wine vinegars during their elaboration in barrels made from different woods

Changes in the volatile components of red wine vinegars and balsamic vinegars were investigated during 1 year of aging in wood barrels and bottles. Barrels of four different woods (oak, chestnut, acacia and cherry) were used. A total of 57 volatile compounds were analysed by Gas Chromatography–Flame Ionization Detection (GC–FID) and Headspace Sorptive Extraction GC–Mass Spectrometry (HSSE-TD–GC–MS). We observed significant increases in the total content of volatile compounds only for balsamic vinegars. The concentrations of ethyl furoate, ethyl benzoate, benzaldehyde and acetophenone were highest in cherry barrels. These compounds, then, seem to be characteristic of this wood. Oak lactones presented the highest increases for vinegars aged in oak. Eugenol was only present in vinegars aged in chestnut and oak barrels. Oak and cherry seem to be the best type of wood for aging of vinegar due to their distinctive aromatic characteristics.     

Fingerprint of volatile flavour constituents and antioxidant activities of teas from Thailand

The volatile flavour components of different teas growing in Thailand were extracted using the simultaneous distillation and extraction (SDE) technique. These volatiles were investigated by GC–MS. At least 54 components representing 76.51–83.32% of all samples were identified. Hotrienol, geraniol and linalool were found to be the major components in Green Oolong tea. Green Assam tea contained linalool, geraniol and α-terpineol as the key flavour constituents. Chin Shin Oolong tea was dominated by linalool, indole and cis-jasmone whilst the major flavour volatiles of Chin Hsuan Oolong tea were trans-nerolidol, cis-jasmone and geraniol. Indole, geraniol and cis-jasmone were detected as the main constituents in Four Season tea. Change of quality and quantity of volatile flavour components was related to fermentation methods that increased volatiles were illustrated by the semi-fermented tea processing method. Green Assam tea infusion extract was evaluated to have the strongest antioxidant activities with the highest amount of phenol content followed by Four Season tea, Chin Shin Oolong tea, Chin Hsuan Oolong tea and Green Oolong tea, respectively.     

Contribution of free and glycosidically-bound volatile compounds to the aroma of muscat “a petit grains” wines and effect of skin contact

Free and glycosidically-bound volatile compounds of must, skin and wine from Muscat “a petit grains” cultivated in Spain were determined, and the effect of different skin contact times on the aroma composition and sensory characteristics of wines was investigated. Must and wine had a large quantity of mono-terpenes, mainly linalool, geraniol, and nerol. The most abundant glycosylated fraction was the mono and poly-oxygenated terpenes, followed by benzene compounds and norisoprenoids. Must skin contact at 18 °C during 15 and 23 h produced an important increase in the free and bound varietal compounds, which suggests the use of glycosidic enzymes, together with skin maceration, to increase wine aroma. From a sensory standpoint, must skin contact was very positive, since it brought about an increase in the fresh and fruity characteristic of the wines, and they also had more body.     

On-line dynamic HS-SPME for monitoring endogenous aroma compounds released during the baking of a model cake

This work shows that using a dynamic SPME device combined with an instrumented oven, it is possible to monitor the release of a large amount of volatile compounds generated during the baking process of a real cereal product (sponge cake model) by directly sampling its baking vapours. The steam assisted dynamic SPME device made it possible to extract volatile compounds with very different volatility and hydrophobicity, such as 5-hydroxymethylfurfural and 2-methyl-propanal. Time dependent analyses of baking vapours made it possible to simultaneously follow the release of several odour compounds and thermal reaction markers at different stages of their generation in the sponge cake model. The release of newly formed aroma compounds during baking significantly affected the odour quality of baking extracts as shown by odour profiles and sensory preferences evaluated by Direct-GC–Olfactometry. GC–Olfactometry analysis was carried out on the final baking fractions to gain an understanding of the compounds which could contribute to overall odour quality.     

Volatile and carbohydrate composition of rare unifloral honeys from Spain

Volatile composition and carbohydrate content of Spanish honey samples from uncommon botanical origins have been studied by gas chromatography coupled to mass spectrometry. About 100 volatile compounds were identified; some of them appeared to be characteristic of particular honey types, such as methyl salycilate in willow (Salix spp.), 2,6,6-trimethyl-2,4-cycloheptadien-1-one (eucarvone) in almond tree (Prunus dulcis) and isophorone in strawberry-tree (Arbutus unedo). Concentration ranges for major carbohydrates were similar to those previously reported in other honeys with different botanical origins, although concentrations of maltulose in avocado honeys (Persea americana) and of melezitose in Quercus ilex honeys were higher. Some carbohydrate alcohols could also be considered as markers of honey botanical origin, such as quercitol for Q. ilex and perseitol for avocado.     

Determination of volatile compounds and quality parameters of traditional Istrian dry-cured ham

The aim of this work was to determine the characteristics of Istrian dry-cured ham by instrumental methods and sensory analysis. The aroma-active compounds of Istrian dry-cured ham from 2010 and 2012 were investigated by using headspace-solid phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). Samples of biceps femoris were also evaluated by measuring physical and chemical characteristics. 92 volatile aroma compounds of Istrian dry-cured ham were found. Volatile compounds belonged to several chemical groups: aldehydes (51.4; 51.3%), terpenes (16.5; 16.4%), alcohols (15.5; 13.2%), ketones (8.6; 7.4%), alkanes (3.8; 5.7%), esters (1.3; 1.6%), aromatic hydrocarbons (0.8; 3.9%) and acids (0.6; 0.9%). Principal component analysis (PCA) showed that fat content, tenderness and melting texture were positively correlated. Terpenes were strongly correlated with flavour of added spices. Sweet taste and the presence of esters were positively correlated as well as negative odour, raw meat flavour and water content.     

Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder

Delipidation was studied as a way to dearomatise a non-conventional protein powder obtained from Eisenia foetida earthworms. In the first step, we studied the impact of several factors such as solvent type, extraction method and particle size on the yield of extracted lipids. Lipid extraction from samples was considerably improved using an ultrasound method with a chloroform/methanol mixture and small particle size. In the second step, the volatile compounds were extracted from the delipidated protein powder by the SAFE extraction method and by the HS-SPME method, and were further analysed by GC–MS. The chloroform/methanol mixture and the ultrasound method extracted a wide range of volatile compounds very efficiently. Moreover, whatever method was used to extract the lipids, the volatile compounds detected in the headspace of the delipidated powder represented less than ¼ of the volatile compounds detected in the headspace of the regular powder.     

Characterization of the volatility of flavor compounds in alcoholic beverages through headspace solid-phase microextraction (HS-SPME) and mathematical modeling

The volatility of flavor compounds (10 distinctive esters commonly found in alcoholic beverages) was characterized using headspace solid-phase microextraction (HS-SPME) analysis combined with mathematical modeling. The impacts of extrinsic factors (extraction time and temperature) and intrinsic parameters (ethanol content and concentration of these flavor compounds) were evaluated on their influences. From extraction profiles, different kinetic behaviors of flavor compounds revealed that volatility is influenced by chemical natures (that is, molecular weight and physicochemical properties). Moreover, volatility was also found to be interrelated with extraction temperature and absorption/adsorption on the fiber's surface. Through mathematical modeling, the kinetic constants of these volatile compounds were computed, and their release profiles were determined. Finally, it was observed that an increase of ethanol (a competitive interference compound to flavor compounds) could decrease the extraction efficiency. Our studies indicated that this approach might be a rapid and practical method that would provide a better understanding of flavor release behavior from alcoholic beverages. PRACTICAL APPLICATION: The proposed approach may provide a simple and fast method in predicting the performance of key aroma esters in different alcoholic beverages. It could also be a practical way in quality control during the production of alcoholic beverage by monitoring key aroma esters.     

Effects of texture and temperature on the kinetic of aroma release from model dairy custards

The structure of a foodstuff, and its perceived texture, are important characteristics involved in the sensory availability of flavour compounds released during the food consumption. This study identifies the effect of texture on the dynamic release of aroma compounds under simulated oral conditions (temperature and shearing). Two custard desserts, with two levels of texture but the same composition, flavoured with four aroma compounds, were analysed. The rheological behaviour of the custards and the release of aroma compounds (SPME analysis) were simultaneously followed, using a mouth simulator. The custard with the lowest texture level showed the highest kinetic release for all aroma compounds studied. With fast increase of temperature (10–25 °C), the decrease in viscosity of the custards and its impact on flavour release seemed to be less important than the heat transfer inside the products and its effect on partition of aroma compounds.     

Authentication study of volatile flavour compounds composition in Slavonian traditional dry fermented salami “kulen”

Volatiles from famous Slavonian salami “kulen” were isolated by nitrogen purge and steam distillation (NPSD) and analysed, for the first time, by gas chromatography and mass spectrometry (GC and GC–MS). In all, 119 organic compounds were identified that originated from lipid oxidation, amino acid degradation, smoke treatment and added spices with different distribution among NPSD traps. NPSD method enabled comprehensive profiling with almost exclusive distribution of several major compounds in particular trap with little or no interference from abundant lipid constituents in the samples. The major identified flavour important compounds were methylphenols, methoxyphenols, organosulphur compounds (diallyl sulphide, diallyl disulphide, methylallyl disulphide, diallyl trisulphide and methional) and several derivatives of 2-cyclopenten-1-one such as ethyl cyclotene. Non-important flavour constituents such as high-molecular fatty acids, alcohols and aldehydes were also present among abundant compounds. General trends for possible discrimination of “kulen” volatiles profile among other European salami volatiles were noticed (lower amount of terpenes and higher percentages of diallyl sulphide, methoxyphenols, methylphenols and 2-cyclopenten-1-one derivatives).     

Characterisation of the mushroom-like flavour of Melittis melissophyllum L. subsp. melissophyllum by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography (GC–FID) and gas chromatography–mass spectrometry (GC–MS)

1-Octen-3-ol is an eight-carbon alcohol responsible for the unique fungal aroma and flavour of edible mushrooms. Among Lamiaceae plants, the highest concentration of this molecule was detected in Melittis melissophyllum subsp. melissophyllum growing in central Italy. On this basis in the present study a HS-SPME coupled with GC–FID and GC–MS was performed to check the influence of several analytical parameters on the amount of 1-octen-3-ol from the plant matrix. Results showed that 1-octen-3-ol is produced in the plant matrix independently from the harvesting time by an enzyme reaction that is enhanced by the optimisation of the extraction conditions (extraction temperature, 40 °C; water addition, 20 μl; extraction time, 30 min; particle size, 1 mm, sample amount, 30 mg). These findings revealed that M. melissophyllum is the first example of a plant, that under appropriate conditions, may be used as a mushroom-like flavouring agent in food products.     

Influence of deficit irrigation and kaolin particle film on grape composition and volatile compounds in Merlot grape (Vitis vinifera L.)

The effect of deficit irrigation and a kaolin-based, foliar reflectant particle film (PF) on grape composition and volatile compounds in Merlot grapes was investigated over two growing seasons in semi-arid, south-western Idaho. Vines were provided with differential amounts of water based on their estimated crop evapotranspiration (ET_c) throughout berry development, and particle film was applied to half of the vines in each irrigation main plot. Free and bound volatile compounds in grapes were analyzed using stir bar sorptive extraction–gas chromatography–mass spectrometry (SBSE–GC–MS). The concentrations of free C₆ compounds (hexanal, trans-2-hexenal, and 1-hexanol) decreased, and bound terpene alcohols (nerol and geraniol) and C₁₃-norisoprenoids (β-damascenone, 3-hydroxy-β-damascenone, 1,1,6-trimethyl-1,2-dihydronaphthalene, and 3-oxo-α-ionol) increased in berries each year in response to severity of vine water stress. Concentrations of C₁₃-norisoprenoids and bound forms of nerol and geraniol were positively correlated with their concentrations in the corresponding wines. Particle film application had minimum effect on free and bound volatile composition in the grapes, and there was no interactive effect between particle film and deficit irrigation. However, particle film application enhanced the total amount of berry anthocyanins.     

Electronic nose and GC–MS analysis of volatile compounds in Tuber magnatum Pico: Evaluation of different storage conditions

The characteristic aromatic composition of white truffles (Tuber magnatum Pico) determines its culinary and commercial value. However modifications of truffle organoleptic proprieties occur during preservation. A study of headspace of white truffles by using Electronic nose (E-nose), gas chromatography–mass spectrometry (GC–MS) and sensory analyses was performed. Truffles were stored at different conditions for 7 days: +4 and +8 °C wrapped in blotting paper or covered by rice or none of the above. Headspace E-nose measurements and sensory analyses were performed each day. Statistical multivariate analysis of the data showed the capability of E-nose to predict sensorial analysis scores and to monitor aroma profile changes during storage. Truffle’s volatile molecules were also extracted by headspace solid phase microextraction technique and separated and identified by GC–MS. Partial Components Analysis of data was performed. E-nose and GC–MS results were in agreement and showed that truffle storage in paper at +8 °C seemed to be the best storage condition.