Flavour and Fragrance Journal最新文献

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).

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.