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This study investigated the impact of different ageing containers on the volatile composition and quality of Negroamaro wine, a key variety from Apulia, Italy. Seven vessel types were evaluated: traditional Apulian amphorae (ozza), five types of oak barrels (American oak, French oak, European oak, a French + European oak and a multi-wood mix) and glass bottles as the control. The impact of the vessels was evaluated after 6 months of ageing through the characterization of phenolic, volatile and sensory profiles. Amphorae allowed a specific evolution of the wine's primary aromas, such as fruity and floral notes, while enhancing volatile compounds like furaneol, which contributed to caramel and red fruit nuances, and also 3-methyl-2,4-nonanedione, a key compound related to anise, plum and premature ageing, depending on its concentration. This container also demonstrated effectiveness in stabilizing anthocyanin–tannin complexes, supporting color stabilization. Oak barrels allowed different outcomes to be obtained in terms of color stabilization, volatile profile, aroma and astringency. French oak exhibited the highest phenolic and tannin levels, enhancing anthocyanin stabilization and color intensity. European oak followed closely, while American oak excelled in color stabilization, with tannins less reactive to polymers. Mixed wood barrels showed lower phenolic extraction and the best astringency evolution. [ABSTRACT FROM AUTHOR]

This study investigated the impact of different ageing containers on the volatile composition and quality of Negroamaro wine, a key variety from Apulia, Italy. Seven vessel types were evaluated: traditional Apulian amphorae (ozza), five types of oak barrels (American oak, French oak, European oak, a French + European oak and a multi-wood mix) and glass bottles as the control. The impact of the vessels was evaluated after 6 months of ageing through the characterization of phenolic, volatile and sensory profiles. Amphorae allowed a specific evolution of the wine’s primary aromas, such as fruity and floral notes, while enhancing volatile compounds like furaneol, which contributed to caramel and red fruit nuances, and also 3-methyl-2,4-nonanedione, a key compound related to anise, plum and premature ageing, depending on its concentration. This container also demonstrated effectiveness in stabilizing anthocyanin–tannin complexes, supporting color stabilization. Oak barrels allowed different outcomes to be obtained in terms of color stabilization, volatile profile, aroma and astringency. French oak exhibited the highest phenolic and tannin levels, enhancing anthocyanin stabilization and color intensity. European oak followed closely, while American oak excelled in color stabilization, with tannins less reactive to polymers. Mixed wood barrels showed lower phenolic extraction and the best astringency evolution.

β‐Damascenone, which has a characteristic sweet and fruity aroma, is a key flavour of various food and drinks, including sweet potato shochu, a Japanese traditional spirit. The compound in the spirits is known to be hydrolytically generated and liberated from progenitors in sweet potato during the manufacturing processes. However, thus far, the progenitors have not been well investigated. In this study, we isolated and identified 11 glycosidic progenitor compounds 1–11 using various chromatographic and spectroscopic techniques combined with a hydrolysis assay. These progenitors consist of two types of aglycones [3,5,9‐trihydroxymegastigma‐6,7‐diene (A1) and 3,9‐dihydroxymegastigma‐4,6,7‐triene (A2)] and four types of glycones [β‐d‐glucopyranoside (G1), (2‐O‐β‐apiofuranosyl)‐β‐d‐glucopyranoside (G2), (6‐O‐β‐xylopyranosyl)‐β‐d‐glucopyranoside (G3) and (2‐O‐β‐d‐apiofuranosyl,6‐O‐β‐d‐xylopyranosyl)‐β‐d‐glucopyranoside (G4)]. Aglycones A1 and A2 are known as direct precursors of β‐damascenone, and compounds 1–3, which have A1 as an aglycone, have been previously reported from other plant materials. On the other hand, compounds 4–11 are newly characterized as glycosidic progenitors of β‐damascenone. [ABSTRACT FROM AUTHOR]

As a C13-norisoprenoid aroma substance, β-damascenone is a highly important aromatic compound and an active constituent. The purpose of this study was to investigate the change law of β-damascenone during the light-flavor Baijiu brewing process, and screen the indigenous microbial strains that produce this compound and optimize fermentation parameters for improving β-damascenone production using a statistical approach. In this project, Wickerhamomyces anomalus YWB-1 exhibited the highest producing activity of β-damascenone. Fermentation conditions were optimized for β-damascenone production using a one-factor-at-a-time (OFAT) approach. A Plackett-Burman design was subsequently adopted to assess the effects of initial pH, incubation temperature, inoculum size, fermentation period, and original Brix degree. Analysis of variance (ANOVA) showed that the correlation coefficient (R2 ) of the executive model was 0.9795, and this value was significant (p < 0.05). Three significant variables were optimized at three different coded levels using a Box-Behnken design (BBD) of response surface methodology (RSM). Here, 7.25 µg/L β-damascenone was obtained under the following optimum conditions: initial pH of 3.31, original Brix degree of 10.53%, and fermentation period of 52.13 h. The yield was increased 3.02-fold compared with that obtained under unoptimized conditions. This information is conducive to the control of flavor production by regulating variable parameters in Baijiu fermentation. [ABSTRACT FROM AUTHOR]

β-Damascenone, a C13-norisoprenoid, is an important aroma compound not only in wine but also in the perfume and flavouring industries. Its key contribution to the floral aromas of many wine varieties, and impact on the overall wine aroma profile, make its quantification in various matrices of increasing interest and demand. The stable isotope dilution assay (SIDA) is one of the most precise analytical methods based on using isotopically labelled standards. Herein, we describe the synthesis of d6-β-damascenone, d6-β-damascone, and d6-safranal, other aroma compounds in nature, starting from the readily available deuterated starting material d6-acetone.

Dehydration or drying of grapes is one of the most important steps in the production of Croatian traditional dessert wine Prošek. The natural sun drying of grapes is the traditionally used method in Prošek production. Alternative methods, such as dehydration under controlled conditions, have been studied as safer and faster methods than the traditional sun drying but without precise knowledge of the effect on volatile compounds. The objective of this work was to study how dehydration of grapes carried out in a greenhouse and an environmentally controlled chamber impacts on the free and glycosidically bound volatile compounds of native grape cv. 'Maraština'. The 36 volatile compounds were identified and quantified using headspace solid-phase micro extraction coupled with gas chromatography-mass spectrophotometry (HS-SPME-GC/MS). The results showed that the aroma profile of dehydrated grapes was significantly different from that of fresh grapes. Regarding free forms, significant increases in the concentration of 2-methyl-1-propanol, 1-butanol, 2-hexen-1-ol, 1-hexanol, ethyl hexanoate, hexyl acetate, o-cymene, linalool oxide, and terpinen-4-ol and geraniol were found in greenhouse-dried grapes, whereas increases in cis-limonene-epoxide, trans-limonene epoxide, and γ-hexalactone were higher in chamber-dried grapes compared to greenhouse-dried grapes. Glycosidically bound forms of o-cymene, linalool oxide, linalool, and terpinen-4-ol were increased in both types of drying, whereas β-damascenone was increased only in greenhouse-dried grapes. [ABSTRACT FROM AUTHOR]

In order to identify active constituents and to gain some information regarding their mode of action, extracts from leaves of Epipremnum pinnatum were tested for their ability to inhibit inflammatory gene expression in endothelial- and monocyte-like cells (HUVECtert and THP-1, respectively). Bioactivity-guided fractionation using expression of PTGS2 (COX-2) mRNA as a readout resulted in the isolation of two C13 megastigmane glycosides, gusanlungionoside C (1) and citroside A (3), and the phenylalcohol glycoside phenylmethyl-2-O-(6-O-rhamnosyl)-ß-D-galactopyranoside (2). Further analysis identified six additional megastigmane glycosides and the aglycones β-damascenone (10), megastigmatrienone (11), 3-hydroxy-β-damascenone (12), and 3-oxo-7,8-dihydro-α-ionol (13). Pharmacological analysis demonstrated that 10 inhibits LPS-stimulated induction of mRNAs encoding for proinflammatory cytokines and leukocyte adhesion molecules, such as TNF-α, IL-1β, IL-8, COX-2, E-selectin, ICAM-1, and VCAM-1 in HUVECtert and THP-1 cells. 10 inhibited induction of inflammatory genes in HUVECtert and THP-1 cells treated with different agonists, such as TNF-α, IL-1β, and LPS. In addition to mRNA, also the upregulation of inflammatory proteins was inhibited by 10 as demonstrated by immune assays for cell surface E-selectin and secreted TNF-α. Finally, using a luciferase reporter construct, it was shown, that 10 inhibits NF-κB-dependent transcription. Therefore, we hypothesize that inhibition of NF-κB by β-damascenone (10) may represent one of the mechanisms underlying the in vitro anti-inflammatory activity of Epipremnum pinnatum extracts.

In order to identify active constituents and to gain some information regarding their mode of action, extracts from leaves of Epipremnum pinnatum were tested for their ability to inhibit inflammatory gene expression in endothelial- and monocyte-like cells (HUVECtert and THP-1, respectively). Bioactivity-guided fractionation using expression of PTGS2 (COX-2) mRNA as a readout resulted in the isolation of two C13 megastigmane glycosides, gusanlungionoside C (1) and citroside A (3), and the phenylalcohol glycoside phenylmethyl-2- O -(6- O -rhamnosyl)-ß-D-galactopyranoside (2). Further analysis identified six additional megastigmane glycosides and the aglycones β-damascenone (10), megastigmatrienone (11), 3-hydroxy-β-damascenone (12), and 3-oxo-7,8-dihydro-α-ionol (13). Pharmacological analysis demonstrated that 10 inhibits LPS-stimulated induction of mRNAs encoding for proinflammatory cytokines and leukocyte adhesion molecules, such as TNF-α, IL-1β, IL-8, COX-2, E-selectin, ICAM-1, and VCAM-1 in HUVECtert and THP-1 cells. 10 inhibited induction of inflammatory genes in HUVECtert and THP-1 cells treated with different agonists, such as TNF-α, IL-1β, and LPS. In addition to mRNA, also the upregulation of inflammatory proteins was inhibited by 10 as demonstrated by immune assays for cell surface E-selectin and secreted TNF-α. Finally, using a luciferase reporter construct, it was shown, that 10 inhibits NF-κB-dependent transcription. Therefore, we hypothesize that inhibition of NF-κB by β-damascenone (10) may represent one of the mechanisms underlying the in vitro anti-inflammatory activity of Epipremnum pinnatum extracts. [ABSTRACT FROM AUTHOR]

Dehydration or drying of grapes is one of the most important steps in the production of Croatian traditional dessert wine Prošek. The natural sun drying of grapes is the traditionally used method in Prošek production. Alternative methods, such as dehydration under controlled conditions, have been studied as safer and faster methods than the traditional sun drying but without precise knowledge of the effect on volatile compounds. The objective of this work was to study how dehydration of grapes carried out in a greenhouse and an environmentally controlled chamber impacts on the free and glycosidically bound volatile compounds of native grape cv. ‘Maraština’. The 36 volatile compounds were identified and quantified using headspace solid-phase micro extraction coupled with gas chromatography-mass spectrophotometry (HS-SPME-GC/MS). The results showed that the aroma profile of dehydrated grapes was significantly different from that of fresh grapes. Regarding free forms, significant increases in the concentration of 2-methyl-1-propanol, 1-butanol, 2-hexen-1-ol, 1-hexanol, ethyl hexanoate, hexyl acetate, o-cymene, linalool oxide, and terpinen-4-ol and geraniol were found in greenhouse-dried grapes, whereas increases in cis-limonene-epoxide, trans-limonene epoxide, and γ-hexalactone were higher in chamber-dried grapes compared to greenhouse-dried grapes. Glycosidically bound forms of o-cymene, linalool oxide, linalool, and terpinen-4-ol were increased in both types of drying, whereas β-damascenone was increased only in greenhouse-dried grapes.

Olfactory cues are key drivers of our multisensory experiences of food and drink. For example, our perception and enjoyment of the flavour and taste of a wine is primarily steered by its aroma. Making sense of the underlying smells that drive consumer preferences is integral to product innovation as a vital source of competitive advantage in the marketplace, which explains the intense interest in the olfactory component of flavour and the sensory significance of individual compounds, such as one of the most important apocarotenoids for the bouquet of wine, β-ionone (violet and woody notes). β-Ionone is formed directly from β-carotene as a by-product of the actions of carotenoid cleavage dioxygenases (CCDs). The biological production of CCDs in microbial cell factories is one way that important aroma compounds can be generated on a large scale and with reduced costs, while retaining the ‘natural’ moniker. The CCD family includes the CCD1, CCD2, CCD4, CCD7 and CCD8; however, the functions, co-dependency and interactions of these CCDs remain to be fully elucidated. Here, we review the classification, actions and biotechnology of CCDs, particularly CCD1 and its action on β-carotene to produce the aromatic apocarotenoid β-ionone.

It is widely accepted that prevéraison application of naphthaleneacetic acid (NAA) can delay the ripening of grapes and improve their quality. However, how NAA impacts grape aroma compound concentrations remains unclear. This study incorporated the analyses of aroma metabolome, phytohormones, and transcriptome of Vitis vinifera L. cv. Cabernet Sauvignon grapes cultivated in continental arid/semiarid regions of western China. The analyses demonstrated that NAA application increased β-damascenone and 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) in the harvested grapes by delaying véraison and upregulating VvPSY1 and VvCCD4b expressions. Additionally, NAA treatment decreased 2-isobutyl-3-methoxypyrazine (IBMP) at the same phenological stage. Notably, abscisic acid (ABA) levels increased in NAA-treated grapes during véraison, which triggered further changes in norisoprenoid metabolisms. The ABA-responsive factor VvABF2 was potentially involved in VvPSY1 positive modulation, while the auxin response factor VvARF10 may play a role in VvCCD4b upregulation and VvOMT2 downregulation during NAA induction. VvARF10 possibly acts as a crosstalk node between the ABA and auxin signaling pathways following NAA treatment in regulating aroma biosynthesis.

The popularity of texiang aroma type baijiu (liquor), known for its unique production technology and multilayered flavor, has been steadily increasing among consumers. So far, no research has determined its key aroma compounds for characterizing the unique flavor, which is the purpose of this paper. Using gas chromatography-olfactometry (GC-O) coupled with the GC-mass spectrometry (GC-MS) method, 87 aroma-active compounds were identified and screened out with intensity values ≥2.0. 1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) was first confirmed by GC-O in Chinese liquor. According to a quantitative study and odor activity values (OAVs), 42 odorants were determined as important aroma compounds. These odorants were recombined based on quantitative concentrations, successfully simulating the overall aroma profile. Omission experiments verified ethyl hexanoate, β-damascenone, and 2-furfuryl ethyl ether as the key aroma compounds and revealed that ethyl acetate, furfural, and ethyl 2-phenylacetate were important aroma compounds to the overall flavor of texiang aroma and flavor type liquor.

In view of climate change, the scheduling of an early harvest may be an agronomic option to limit wine alcohol, provided that a satisfactory content of secondary metabolites can be ensured in grapes. To better understand the link between grape ripening, seasonal trend and wine aroma, the aromatic expression of Barbera and Pinot Noir wines produced with early harvested grapes was assessed. Attention was focused on C13 norisoprenoids during both alcoholic fermentation and after three months of storage. At the end of fermentation, the highest β-damascenone content was detected in wines obtained from less ripe grapes, the content subsequently increased significantly after three months of storage; however, the levels of β-ionone decreased significantly during the same period. The reduction of wine alcohol as a result of harvesting earlier, especially for Barbera, was associated with optimal aromatic levels as well as good technological parameters. [ABSTRACT FROM AUTHOR]

Doubanjiang, a Chinese traditional fermented red pepper paste, is eaten worldwide for its unique flavor. The objective of this study was to evaluate the aroma quality of doubanjiang using solvent-assisted flavor evaporation (SAFE) and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). A total of 165 volatile compounds, belonging to 13 chemical classes, were identified. Esters and hydrocarbons were the predominant groups. Thirteen aroma-active compounds were detected by AEDA of SAFE and HS-SPME, and their odor activity values (OAVs) were calculated by dividing their concentration by their odor threshold in water. Among them, ethyl isovalerate, β-damascenone, 3-isobutyl-2-methoxypyrazine (IBMP), and sotolone had the highest OAVs (>1000). In addition, sotolone, methional, β-damascenone, 3-isobutyl-2-methoxypyrazine, ethyl isovalerate, phenylethyl alcohol and linalool had high flavor dilution (FD) factors. Sotolone, β-damascenone and 3-isobutyl-2-methoxypyrazine were identified for the first time in doubanjiang and played significant roles in its aroma quality.

A field study was conducted in north-central San Joaquin Valley of California to deduce the interactive effects of irrigation and mechanical canopy management on the phenolic composition of grape and wine, and volatile compounds of the wines produced from Syrah ( Vitis vinifera L.). The irrigation treatments consisted of a grower control of 70% crop evapotranspiration (ET c ) replacement (IRR-I) from anthesis to harvest, compared to a stronger plant water stress between fruit set and veraison with 50% ET c replacement, otherwise 70% ET c replacement rest of the season (IRR-II). Four canopy management treatments were crossed with the irrigation design. A control treatment was pruned by hand to 22 two-node spurs (C) with no further manipulation. Experimental canopy management treatments (CM) consisted in mechanically box pruning the vines to a 0.10 m hedge combined with 3 levels of mechanically shoot thinning: heavy shoot thinning (M1), light shoot thinning (M2) and no shoot thinning (M3). In this two-year study, the irrigation treatments had no impact on the canopy architecture, but mechanization treatments were effective. However, this study reports sensitivity of canopy management to weather conditions in previous and current year, therefore to vintage effect. The irrigation treatments affected berry composition more than mechanization, and the effect was insensitive of the vintage effect. The IRR-II reduced berry weight, resulting in reduced yield and crop load in both years but greater berry anthocyanins, tannins and total phenolics. For anthocyanins, this result was also confirmed on wine. One year was characterized by higher amount of precipitation at fruit set, and in this year the concentration in 3-isobutyl-2-methoxypyrazine was higher, but the concentration of terpenes and norisoprenoids was lower, with the exception of β-damascenone that was stable between years but increased with IRR-II. In typical years, where no precipitation is received in the San Joaquin Valley from fruit set to veraison, the M2 and IRR-II method may contribute to improve berry skin and wine phenolics as well as to reducing IBMP in wine while achieving high yields. This trial showed that precipitation can modulate the impact of cultural practices on grape and wine composition, and that lower irrigation amounts do not correspond to reduced wine quality even in the semi-arid and warm conditions of Central California. [ABSTRACT FROM AUTHOR]

BACKGROUND During an investigation of the chemical profile of Greek figs ( Ficus carica L.), several aqueous ethanol extracts (liquors) were prepared from dried Smyrna fig varieties cultivated in the two major fig-producing geographical areas in Greece: Peloponnese and Evia Island. The distinctive aroma observed among the prepared fig liquors led to the investigation of the odor profile of the different fig cultivars through HS-SPME coupled with GC/ MS analysis, with focus on the factors that affect it before and during the preparation of the respective liquors. RESULTS Significant variation in volatiles was noticed among all fig cultivars, as also between each fig cultivar pulp and the respective liquor. The observed diversity was a result of chemical reactions taking place in the ethanol matrix during the preparation of the liquor. The 'key' odor compound of dried fig aroma was found to be β-damascenone. Owing to its low detection threshold and minute quantity in fig cultivars, the presence of β-damascenone was furthermore confirmed through GC/ MS/ MS and GC/ TOF-MS. β-Damascenone was identified in variable quantities among fig varieties and their liquors, predominating in Kalamon fig cultivar of Peloponnese region, while its amount was found to be dependent on the postharvest storage time and preservation process of dried figs. CONCLUSION Each of the studied fig cultivars and liquors showed a unique aroma profile, and the obtained results were used for the preparation of the first dried fig liqueur for potential commercial use with the highest content of β-damascenone. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The impacts of fruit zone leaf removal on volatile and anthocyanin compositions of Pinot noir wine were investigated over two growing seasons. Wine volatiles were analyzed by multiple techniques, including headspace solid phase microextraction-GC-MS (HS-SPME-GC-MS), headspace-GC-FID (HS-GC-FID) and stir bar sorptive extraction-GC-MS (SBSE-GC-MS). Fruit zone leaf removal affected the concentration of many grape-derived volatile compounds such as terpene alcohols and C 13 -norisoprenoids in wine, although the degree of impact depended on the vintage year and severity of leaf removal. Fruit zone leaf removal resulted in greater concentrations of linalool, α-terpineol and β-damascenone but had no impact on other terpene alcohols or β-ionone. Fruit zone leaf removal had no consistent impact on C6 alcohols, volatile phenols, lactones, fermentation-derived alcohols, acids, or most esters. Fruit zone leaf removal increased anthocyanins in final wine. [ABSTRACT FROM AUTHOR]

The dehydrogenative synthesis of β-damascenone from β-damascone via the related allyl bromide intermediate was studied in depth. The requisite dehydrobromination thereof was found strongly solvent system dependent. Under respective conditions, the product was identified as dehydrogenation-derived a, 4-alkoxy-derived b and 4-oxo-derived c, accordingly. In addition, the conversion from b to a was successfully accomplished, thereby offering an alternative access (with one step more) to reach β-damascenone. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The influence of cluster-zone leaf removal on Pinot noir vine growth and fruit chemical and volatile composition was investigated in 3 years. Different severities of leaf removal (0%, 50%, 100%) were imposed during the pea-size stage of development from the cluster zone. Results show that cluster-zone leaf removal had little influence on vine growth, crop load, or grape maturity in terms of total soluble solids (TSS), pH or titratable acidity (TA) at harvest. However, 100% leaf removal resulted in higher concentrations of quercetin glycoside in grapes compared to 0% leaf removal. The 100% leaf removal also increased concentrations of petunidin- and malvidin-3-monoglucoside anthocyanins in two out of 3 years (2010 and 2012) by an average of 62% and 53%, respectively. In addition, 100% leaf removal resulted in higher concentrations of β-damascenone, and some bound-form terpenoids. The increases in β-damascenone were positively correlated to the increased sunlight exposure. [ABSTRACT FROM AUTHOR]

ABSTRACT The effect of wine closures on volatile composition during post-bottle ageing was investigated for Pinot Noir and Chardonnay wines. Natural cork, synthetic cork and screw caps with Saran-tin, Saranex and low density polyethylene (LDPE) liners were investigated over 3 years of storage. Dissolved O2 and SO2 as well as colour were monitored. Volatile sulfur compounds, esters, terpene alcohols, and C13-norisoprenoids were quantified every 6 months over 3 years. The results showed that the LDPE screw cap gave the highest dissolved oxygen, lowest free SO2 and total SO2 in both wines, while the Saran-tin screw cap gave the lowest dissolved oxygen and the highest free SO2 and total SO2. A decrease of H2S, methanethiol, and thioacetates were observed during the 3 year ageing process for both wines, and their concentrations decreased most in wines sealed with LDPE screw caps and synthetic closures. The decrease of thioacetates was independent of closure type. The accumulation of dimethyl disulfide during storage was not obvious in these two wines. For both wines, no elevated sulfur compounds under any closure were detected; neither dimethyl disulfide nor dimethyl trisulfide were found in any of the experimental wines. Other volatiles also changed with in bottle ageing. Ethyl esters decreased during ageing, whereas ethyl 2-methylbutanoate and ethyl 3-methylbutanoate increased during ageing. Terpene alcohols showed a decreasing trend with ageing, as was β-damascenone, but β-ionone remained unchanged in Pinot Noir wine during ageing. Both wines under LDPE closure had the highest acetaldehyde at 36 months of ageing. Wine closure affected the concentration of terpene alcohols and C13-norisoprenoids. Closure had no impact on nerolidol and citronellol, but LDPE screw-capped wine had lower concentrations of linalool at 36 months of storage. Both wines with LPDE screw cap closures had higher β-damascenone. Closure had no effect on β-ionone and other compounds. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A method to identify and quantify megastigmane norisoprenoid compounds in wines was developed using headspace solid phase micro extraction (SPME) coupled with gas-chromatography/mass-spectrometry (GC–MS). Three different compounds were quantified by stable isotope dilution assay (SIDA): β-damascenone, β-ionone and α-ionone. Particular attention was paid to maximising the method’s sensitivity while reducing the extraction time. To optimise the extraction conditions, a statistically designed experiment was performed using extraction time, extraction temperature and ethanol content as operating variables. Five different SPME fibres suitable for the analysis of volatile compounds were compared. This study confirmed that the PDMS/DVB coating performs best for the quantification of β-damascenone and β-ionone, and the crucial influence of ethanol content of the sample on extraction effectiveness. Finally, the optimised method was applied to the study of various wines derived from rare and autochthonous grape varieties of north-western Italy. [Copyright &y& Elsevier]

Abstract: Understanding how oral administration of aroma terpenes can prevent sunburn or skin cancer in mice could lead to more effective and safer ways of blocking sun damage to human skin. To establish sunburn preventive activity, female Skh-1 mice were given oral β-damascenone followed by irradiation with UVR from fluorescent ‘sunlamps’. The following endpoints were evaluated versus controls at various times between 1 and 12days after the terpene: whole genome gene expression and in situ immunohistochemistry of PCNA, keratin10, filaggrin and caspase 14, and sunburn was evaluated at 5days. UVR-induced sunburn was prevented by a single oral β-damascenone dose as low as 20μL (0.95mg/g body weight). Microarray analysis showed sunburn prevention doses of β-damascenone up-regulated several types of cornification genes, including keratins 1 and 10, filaggrin, caspase 14, loricrin, hornerin and 6 late cornified envelope genes. Immunohistochemical studies of PCNA labeling showed that β-damascenone increased the proliferation rates of the following cell types: epidermal basal cells, follicular outer root sheath cells and sebaceous gland cells. Keratin 10 was not affected by β-damascenone in epidermis, and filaggrin and caspase 14 were increased in enlarged sebaceous glands. The thickness of the cornified envelope plus sebum layer nearly doubled within 1day after administration of the β-damascenone and remained at or above double thickness for at least 12days. β-Damascenone protected against sunburn by activating a sebaceous gland-based pathway that fortified and thickened the cornified envelope plus sebum layer in a way that previously has been observed to occur only in keratinocytes. [Copyright &y& Elsevier]

Abstract: ASTM international standard practice E679 prescribes the use of a 3-alternative forced-choice (3AFC) method with an ascending concentration series for measuring odour detection thresholds. It recommends obtaining an individual’s threshold by geometrically averaging the concentrations at which the judge’s detection response reverses from incorrect to correct. The legitimate reversal point is defined by a stopping rule. Previous researchers have identified some methodological flaws with this calculation approach, relating to the use of stopping rules and the method’s unconventional definition of thresholds. The current study aims to empirically investigate these issues in more depth. Thresholds for three odorants were obtained for 100 judges. 1,8-Cineole, isobutyraldehyde and β-damascenone were tested in accordance with the data collection procedure of ASTM E679. Initially, thresholds were estimated by the ASTM-based method with four different stopping rules. These estimates were subsequently compared against thresholds estimated by an alternative method; that of fitting psychometric functions. The theoretical grounds on which the latter method is based, and the clear connection between performance and stimulus concentration that it demonstrates, provide a thorough comparison of both conventionally-defined thresholds and method-independent thresholds against the ASTM-based method. Comparisons between the thresholds resulting from the various estimation methods demonstrated (1) the choice of stopping rule had a significant effect on threshold estimates (P <.05); (2) each stopping rule measured a specific level of performance, indicating a useful correspondence between the stopping rules and the psychometric function. These findings provide supporting evidence for the continued use of the ASTM-based method; albeit, if the stopping rule is standardized. One of the tested stopping rules (Stop 3) provided threshold estimates consistent with those estimated for d′=1.0, and is therefore recommended for future research. [Copyright &y& Elsevier]

The formation of β-damascenone during shochu manufacture was investigated by quantifying β-damascenone at each stage of manufacturing. Steamed sweet potato has a low level of free β- damascenone (0.02-0.1 μg/g). During fermentation, β-damascenone was produced in small quantities that were degraded by yeast. Thus, the second mash accumulates little free β-damascenone (approximately 17 μg/L). The concentration profile in the fractionated distillate showed that β-damascenone was produced during heating. Most β-damascenone in shochu was formed during distillation, not during steam heating and fermentation. It is suggested that the level of β-damascenone in shochu could be increased by reducing the pH of the second mash and prolonging the distillation period. Sweet potato cultivars differed in total free and hydrolyzed β-damascenone content and there was a strong association between each cultivar and its shochu β- damascenone content. The selection of the sweet potato cultivar is important for determining the quantity of β-damascenone in a shochu brew. [ABSTRACT FROM AUTHOR]

Abstract: The present manuscript reports the first application of molecular modelling to the design of molecularly imprinted polymers (MIPs) prepared by alkoxysilane sol–gel polymerization. The major goal was to determine the requisite level of theory for the selection of suitable alkoxysilane functional monomers. A comparative study, applied to the design of a MIP for β-damascenone, involving different levels of theory, basis set superposition error (BSSE) correction and basis set augmentation and also semi-empirical methods, was performed. The computations results suggest that the use of the 3-21G basis set concomitantly with a method for BSSE correction represents a good compromise between theory level and computation time for the successful screening of functional monomers. Additionally, a few selected MIPs and their corresponding non-imprinted congeners (NIPs) were prepared and tested in the role of solid-phase extraction (SPE) sorbents. The confrontation of the computational results with the observed performance and morphological characteristics of the prepared MIPs suggest that besides the strength and type of interactions existing between template and functional monomers other concomitant features, related with the sol–gel process, must also be accounted for so that effective molecular imprinting is achieved in an alkoxysilane xerogel. Nevertheless, since an optimal template–functional monomer interaction is a necessary condition for successful imprinting, the choice of the best monomers is still of the greatest importance and the proposed computational method may constitute an expeditious and reliable screening tool. [Copyright &y& Elsevier]

γ- and δ-Pyronenes are terpenic synthons easily available from myrcene. They are used as intermediates in the synthesis of α-damascone, γ-damascones, and β-damascenone. [ABSTRACT FROM AUTHOR]

β-Damascenone and β-damascone derivatives, important fragrant compounds, were directly obtained from β-ionone by a new way via retro-α-ionol. [ABSTRACT FROM AUTHOR]

Abstract: A new method of analysis was previously developed by this group for the determination of β-damascenone in beer samples. The method consisted of a beer steam distillation, followed by an extraction/concentration step using a C18 SPE column and, finally, analysis by reversed-phase liquid chromatography with detection of β-damascenone at its 227nm UV-absorption maximum. This work describes further developments of the previous methodology and its application to the identification and quantification of β-damascenone in some other beverages, such as wine, whiskey and brandy. β-Damascenone concentration was monitored during a forced ageing assay of several wines from different regions of Portugal and the influence of heat treatment of wine on β-damascenone concentration was studied. The effect of pH on β-damascenone concentration is also discussed. [Copyright &y& Elsevier]

Nor-isoprenoid compounds, such as β-damascenone, β-ionone, 2,2,6-trimethylcyclohexanone (TCH), 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) and vitispirane were determined in 14 young port wines and 45 old port wines. As between the two groups of wines levels of these compounds are quite different, an experimental protocol was performed in order to determine which technological parameter (dissolved O2, free SO2 levels, pH and time/temperature) was related with the formation/consumption of these molecules. The five nor-isoprenoids were equally affected by the selected parameters and a similar profile with time was observed. The synergistic effects of increasing temperature and lowering pH had the largest impact. For samples treated with high oxygen regimes (saturation), the levels of all considered nor-isoprenoids decreased after a certain concentration of oxygen consumed (e.g. 10 mg l-1).Nevertheless, during barrel port wine ageing, corresponding to the 45 wines, two different behaviours can be observed: TDN, vitispirane and TCH increase significantly whilst a decrease of levels of β-ionone and β-damascenone with port barrel ageing was observed. It was also calculated that “over 40 year” old port wines have, respectively, 15, 5 and 3 times higher levels of TDN, vitispirane and TCH than the young ports. For these three compounds the respective rates of formation are higher than those of degradation, which suggests a higher number or higher concentration of precursors than those involved for the megastigame C13 nor-isoprenoids β-damascenone and β-ionone. [Copyright &y& Elsevier]

Callus cultures of Vitis labruscana cv. Concord were initiated from both immature fruit and petiole tissue. Analysis revealed that the acid hydrolyzable precursors to β-damascenone, a compound important to the flavor of most grape species, were present in both callus types. Light and increased sucrose concentration were shown to raise the levels of the precursor, some of which are glycosides, in the petiole callus but not in the fruit callus. Addition of β-carotene, a biogenic precursor to β-damascenone and its precursors and the addition of amitrole, an inhibitor of carotenoid cyclization and production, had no effect upon precursor levels in either tissue. Aroma compounds specific to V. labruscana grapes and other American species of grapes were not found in the callus tissue. Cell suspensions were initiated from the fruit callus and analyzed for the American character compounds as well as β-damascenone and its acid hydrolyzable precursors. Once again, no aroma compounds specific to American species were found while β-damascenone precursors were present at levels lower than were found in callus on solid media and only during stationary phase of growth. [ABSTRACT FROM AUTHOR]

• An UV-C dose of 2 kJ/L and pasteurization of must did not cause off-flavors. • High UV-C doses (6 and 21 kJ/L) were found to be detrimental for wines. • Only 21 kJ/L caused above-threshold concentrations of 2-aminoacetophenone. • Changes in volatile compounds, such as terpenes and C13-norisoprenoids were observed. • Linalool was relatively stable; β-damascenone was degraded by UV-C treatment. UV-C treatment is a commonly known technique to inactivate microorganisms. The objective of this work was to investigate the impact of UV-C treatment of grape must on the sensory characteristics of the resulting wine and on the profile of volatile compounds of grape must and wine. Different UV-C doses were applied to Riesling must and compared with thermal pasteurization. The sensory off-flavor "ATA" and a content of 0.5 µg/L 2-aminoacetophenone were determined in the grape must and in the resulting wine after UV-C treatment with a high dose of 21 kJ/L. Sensory off-flavors did neither occur after thermal pasteurization nor after UV-C treatment with a dose of 2 kJ/L, which is sufficient for the inactivation of microorganisms. Minor changes in the volatiles' profiles of grape must and wine, involving e.g. terpenes and C13-norisoprenoids, occurred in musts treated with thermal pasteurization as well as with a UV-C dose of 2 kJ/L. [ABSTRACT FROM AUTHOR]

Olfactory cues are key drivers of our multisensory experiences of food and drink. For example, our perception and enjoyment of the flavour and taste of a wine is primarily steered by its aroma. Making sense of the underlying smells that drive consumer preferences is integral to product innovation as a vital source of competitive advantage in the marketplace, which explains the intense interest in the olfactory component of flavour and the sensory significance of individual compounds, such as one of the most important apocarotenoids for the bouquet of wine, β-ionone (violet and woody notes). β-Ionone is formed directly from β-carotene as a by-product of the actions of carotenoid cleavage dioxygenases (CCDs). The biological production of CCDs in microbial cell factories is one way that important aroma compounds can be generated on a large scale and with reduced costs, while retaining the 'natural' moniker. The CCD family includes the CCD1, CCD2, CCD4, CCD7 and CCD8; however, the functions, co-dependency and interactions of these CCDs remain to be fully elucidated. Here, we review the classification, actions and biotechnology of CCDs, particularly CCD1 and its action on β-carotene to produce the aromatic apocarotenoid β-ionone. [ABSTRACT FROM AUTHOR]

Doubanjiang, a Chinese traditional fermented red pepper paste, is eaten worldwide for its unique flavor. The objective of this study was to evaluate the aroma quality of doubanjiang using solvent-assisted flavor evaporation (SAFE) and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). A total of 165 volatile compounds, belonging to 13 chemical classes, were identified. Esters and hydrocarbons were the predominant groups. Thirteen aroma-active compounds were detected by AEDA of SAFE and HS-SPME, and their odor activity values (OAVs) were calculated by dividing their concentration by their odor threshold in water. Among them, ethyl isovalerate, β-damascenone, 3-isobutyl-2-methoxypyrazine (IBMP), and sotolone had the highest OAVs (>1000). In addition, sotolone, methional, β-damascenone, 3-isobutyl-2-methoxypyrazine, ethyl isovalerate, phenylethyl alcohol and linalool had high flavor dilution (FD) factors. Sotolone, β-damascenone and 3-isobutyl-2-methoxypyrazine were identified for the first time in doubanjiang and played significant roles in its aroma quality. [ABSTRACT FROM AUTHOR]