Flavour and Fragrance Journal最新文献

This study employed headspace solid phase micro-extraction gas chromatography mass spectrometry (HS-SPME-GC–MS) coupled with multivariate statistical analysis to identify volatile markers in various levels of Zhenjiang Aromatic Vinegar (ZAV). A full range of 40 volatile organic compounds (VOCs) were identified and categorized into acids, alcohols, esters, aldehydes, ketones, heterocyclic compounds and others. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) demonstrated a clear clustering effect among different levels of ZAV, indicating distinct volatile characteristics at the relative content level. Furthermore, using Orthogonal partial least squares discrimination analysis (OPLS-DA), 20 significant volatile organic compounds (VOCs) were identified as markers for distinguishing between the various levels of ZAV. To differentiate among the levels of ZAV, two volatile compounds, acetic acid and n-hexanol, were identified as characteristic volatile compounds using a combination of Venn diagram, analysis of variance (ANOVA) and boxplot analysis. The results showed notable variations in VOCs among ZAV samples of different grades. Acetic acid and n-hexanol can serve as reliable markers for grade distinction, providing valuable technical and theoretical support for the production and quality control of ZAV.

Bergamot (Citrus bergamia Risso) is not consumed as fresh fruit as other members of Citrus. Bergamot essential oil has a unique aroma. Bergamot essential oil is a very valuable product used in perfumery, cosmetics, aromatherapy and food industry due to its beautiful scent and functional properties. As with other Citrus species, the composition of bergamot essential oil can vary according to harvest time, climate and extraction technology. Bergamot essential oil could be obtained by cold press extraction or distillation method. Within the scope of the study, the effect of four different hydrodistillation (HD) times (5, 10, 60 and 120 min) on the composition of bergamot essential oil obtained from Turkish fruits was investigated. In the first 60 min, 96.11% of the total essential oil was obtained. Research findings have shown that the distillation time is quite effective in the composition of bergamot essential oil. Limonene, linalool and linalyl acetate, which are the main components of bergamot essential oil, varied in the range, 42.36%–53.25%, 5.59%–12.18% and 20.84%–26.73%, respectively, with respect to distillation time. In cold press method, bergamot essential oil has lower linalool/linalyl acetate ratio (0.15) compared to HD method and a higher quality essence was obtained.

Most dietary intake estimates used in the regulatory risk assessment of flavouring substances assume that the flavouring substance is present in all foods at a given concentration. They do not account for the use of alternate flavouring substances for the same taste modality, nor do they consider the use of differing concentrations within a particular food category. This highly conservative assumption leads to an over-estimation of exposure. To refine this assumption in exposure models, the probability of addition can be utilised. In this study, a methodology to estimate the probability of addition was developed, using the volume of a flavouring substance sold for flavours created for a particular food category against its total volume sold for all flavouring use. The method was trialled, as a proof of principle, using historical data sets of two test flavouring substances, benzaldehyde (a large volume/use material) and bornyl acetate (a low volume/use material), and the impact on dietary exposure assessment was assessed. The resulting exposure estimates for both flavouring substances were shown to be significantly lower than those without the incorporation of probability of addition, demonstrating that current methods are overly conservative and that the use of probability of addition provides a more realistic estimate of exposure of flavouring substances present in foods.

This study aimed to explore the effects of different baking treatments on the quality of Yongchuan Xiuya (YCXY) green tea. It was found that a long time baking at low temperature was beneficial to keep green colour, faint scent, mellow and fresh taste quality, whereas baking under high temperature was adverse to the quality. Baking treatments slightly regulated (−)-epigallocatechin, (−)-epicatechin, (−)-gallocatechin gallate, total chlorophyll and carotenoid. As the baking temperature rose, the content of tea polyphenols, gallic acid, catechins, caffeine, soluble sugar and polyphenols/amino acids ratio obviously decreased. A total of 40 kinds of volatiles were detected in these six tea samples. A model for aroma type discrimination was successfully established based on partial least squares-discriminant analysis (PLS-DA). Ten kinds of volatile substances were the key characteristic markers for the faint scent, chestnut aroma and high-fired aroma types of YCXY green tea. 1-hexanol, hotrienol and dimethyl sulfide were furtherly used to discriminant aroma type based on Fisher discriminant analysis (FDA).

Magnolia biondii flower buds are a well-known medicinal plant in China, and it is important to determine the differences in aroma, flavour components, and biological activity of the essential oils of M. biondii flower buds (EOM) from different origins. In this study, the essential oils of M. biondii flower buds from Sichuan (EOM-SC), Anhui (EOM-AH) and Henan (EOM-HN) provinces were extracted by hydrodistillation. The condition of the extraction process was optimized. The differences in the flavour compounds were further confirmed by GC–MS and relative odour activity value (ROAV) analyses. In addition, the antibacterial and antioxidant activity was also evaluated. The results showed that the optimized condition for steam distillation was water: flower powder ratio = 10:1 with extraction time for more than 3.0 h. Interestingly, special floral, fruity and freshness flavours were found for EOM-SC, and the medicinal herb and sweetness odours of EOM-HN were more prominent. The numbers and contents of flavour compounds in EOM-SC and EOM-HN were higher than those of EOM-AH. Eucalyptol, β-pinene, linalool, α-terpineol and sabinene could be proposed as the key mutual flavour compounds for three essential oils. In addition, the strong floral, fruity and freshness aroma of EOM-SC could be associated with the high ROAVs of α-terpineol, linalool and sabinene. Moreover, EOM-SC exhibited better antibacterial and antioxidant activity than those of the other two essential oils.

The objective of this study was to screen non-Saccharomyces yeast suitable for enhancing the aroma of Yinhong plum wine. Five non-Saccharomyces yeasts with strong ester-producing ability, namely, Wa3 (Wickerhamomyces anomalus), Hu12 (Hanseniaspora uvarum), Pk2A2, PkW2 and PkY2 (Pichia kluyveri), were selected from various naturally fermented fruit juices for molecular biological identification, analyses of physiological characteristics and tolerance and determination of their effects on the flavour of Yinhong plum wine. Analysis of brewing characteristics showed that they differed in their abilities of producing acetic acid, hydrogen sulfide, killer activity and tolerance. Among them, Wa3 showed the best tolerance to high concentrations of alcohol, sugar and SO₂. Compared to the control Saccharomyces cerevisiae FX10, Yinhong plum wine fermented with non-Saccharomyces yeast exhibited a decrease in alcohol content, while residual sugar, glycerol content and the types and quantities of volatile compounds all showed an increase. Among the fermented wines, PkY2 generated the highest content of ester compounds in the fermented wine, which was 5.66 times higher than that generated by the control. The compounds produced by PkY2 were closely related to various ethyl and acetate odour-active compounds (odour-active value >1), which could impart a rich floral and fruity aroma to Yinhong plum wine. Sensory analysis revealed that both floral and fruity aromas were significantly increased in Yinhong plum wine fermented by non-Saccharomyces yeasts, with the highest scores of floral and fruity aromas for PkY2. In conclusion, a Pichia kluyveri strain, PkY2, with excellent brewing characteristics and potential for enhancing the aroma of Yinhong plum wine was identified.

The Persian silk tree (Albizia julibrissin) has delicate flowers with a pleasant aroma profile, displaying notes of hyacinth and rose with subtle nuances of citrus, coconut and spice. In this study, a total of 29 odorants were identified in the flowers from a single A. julibrissin selection by the application of a cold-solvent extraction (CSE), followed by solvent-assisted flavour evaporation (SAFE) and aroma extract dilution analysis (AEDA). Subsequently, nine odorants with flavour dilution (FD) factors ≥16 were quantitated by stable isotope dilution analysis (SIDA), and odour activity values (OAVs) were calculated. Odorants with OAV ≥1 included 2-phenylacetaldehyde (OAV 3638), linalool (OAV 797), eugenol (OAV 231), geraniol (OAV 161), 1H-indole (OAV 93), β-ionone (OAV 31), 2-phenylethanol (OAV 11) and γ-octalactone (OAV 1). An aroma simulation model was prepared based on the quantitation data, and it closely matched the aroma of the flower isolate. Chiral chromatography was performed, and (S)-(+)-linalool was the only enantiomer detected. This study advances our understanding of A. julibrissin flower aroma chemistry and lays the groundwork for future investigations for the development of delicate floral aromas for flavour and fragrance applications.

Sleep disorders are widespread. Inhaled aromatherapy has shown advantages over medication in treating insomnia. Daylily (Hemerocallis fulva) has been found to positively affect sleep either by ingestion or inhalation, but there is a lack of research on the sleep aid effect of its inhalation route. At present, the floral scent characteristics of daylily are not obvious, and the extraction rate of essential oil is low. Based on the above problems, this study developed daylily essence which replicates the natural aroma of plants and investigated the effect of inhaling daylily essence aroma on sleep activity by using Pittsburgh Sleep Quality Index (PSQI) and electroencephalogram (EEG). According to PSQI results, inhaling the aroma of daylily essence improved participants' subjective sleep quality. The difference between men and women was statistically significant (p < .05). The slow-wave sleep activity of EEG in the experimental group was significantly stronger than that in the control group (p < .01). In addition, the frontal and central regions were more responsive to aroma stimuli (p < .05). The results of this study show that the aroma of daylily can promote the subjective and objective sleep quality of healthy college students, and the use of fragrance intervention is a potential scheme to improve sleep quality and insomnia.

This study investigates the impact of baking conditions and initial concentrations of flavourings on the evolution of three key flavourings (benzaldehyde, butyl butyryl lactate, and vanillin) in cookies during baking and subsequent storage. Controlled baking experiments were conducted at two temperatures (130°C and 160°C) with varying initial flavouring concentrations. The results reveal that baking at the higher temperature (160°C) led to a substantial loss of benzaldehyde and butyl butyryl lactate, resulting in a significantly lower proportion of these compounds in the final product compared to baking at 130°C. In contrast, vanillin showed greater stability at the higher temperature, with its proportion in the final product remaining stable or increasing compared to the lower temperature. Specifically, the proportion of benzaldehyde decreased from 18.33% in the dough to 4.31% after 2 weeks of storage for cookies baked at 160°C, whereas the proportion of vanillin increased from 47.24% to 61.38% in the same period. Statistical analysis, employing ANOVA and Tukey–Kramer HSD tests, confirmed the significant effect of baking temperature on the evolution of flavour compounds (p < 0.05). These analyses further revealed the notable influence of initial flavouring concentrations on the changes in benzaldehyde across all tested temperatures, as well as on butyl butyryl lactate and vanillin specifically at 130°C. These results offer valuable insights on how the baking process can be optimized to enhance the sensory profile of cookies and highlight the importance of temperature control and initial flavouring mix design.

Phenylacetaldehyde (PhA) is an aromatic aldehyde which has a hyacinth-like floral, sweet and green-leafy odour. PhA is used as a perfumery chemical and a rate-controlling additive in cosmeceutical and polymer industries, respectively. The conventional process of PhA manufacturing in industries involve hazardous and costly feedstock and often lead to generation of substantial amount of waste. Moreover, usage of stoichiometric reagents often makes the processes economically impractical. This article illustrates the possibility of production of PhA from low-cost feedstock styrene through a single-step, one-pot method wherein various metal oxides have been utilized as catalysts for styrene oxidation under the influence of cumene hydroperoxide (CHP). Ag₂O is found to be the highest PhA-yielding catalyst and a promising candidate for scaling up for its considerably good reusability up to 6 consecutive uses. A maximum of ~45% PhA selectivity has been observed at ~60% styrene conversion. Interestingly, this process does not require any alkaline/acid wash and hence does not produce any organic/inorganic liquid effluent stream. Furthermore, all the major byproducts found, that is styrene oxide, benzaldehyde and acetophenone, are themselves considered as valorized styrene derivatives. Overall, the metal oxide catalysed styrene oxidation has potential to take over the conventional industrial process(es) for sustainable selective production of PhA Along with a plausible mechanism of styrene oxidation over Ag₂O, a conceptualized reaction–separation framework has been reported for intensified production of PhA from CHP-based styrene oxidation.