Flavour and Fragrance Journal最新文献

The optimum reaction conditions (temperature 95°C, pH 6.5, time 70 min and cysteine 0.2 g) and significant influence factors were found by response surface model (RSM) experimentation to reduce bitterness and increase overall acceptability of soybean protein hydrolysate (SPH) using the Maillard reaction of arabinose. Three reaction products of different response values and sensory profiles were selected to be investigated further. Fourier transform infrared (FTIR) spectra and UV 294 and 420 nm analyses revealed their different extents of the Maillard reaction. Partial least squares regression analysis (PLSR) for free amino acids and molecular weight distribution and aroma compounds versus the used reaction conditions of the three samples suggested that reaction conditions of higher pH plus less Cys could cause more bitter amino acids (Leu, Val) and 500–1000 Da peptides, while those of more cysteine plus longer times under low temperatures benefitted formation of the umami amino acid of glutamic acid and > 1000 Da peptides. In particular, the reaction conditions of higher temperatures and more cysteine would generate more volatile compounds with roasted and meaty aromas unfavourable for overall acceptability. Furthermore, Pearson coefficient analysis revealed the key taste and aroma components and exposed that the fatty and caramel aromas contributed positively to overall acceptability. This study can provide references for debittering and improving the flavour of SPH.

Shanxi aged vinegar (SAV) is a traditional vinegar produced mainly in southern China from rice and wheat, undergoing prolonged fermentation for maturation, which distinguishes it from other vinegar. To explore its flavour, a selection of 12 SAV varieties was meticulously chosen for in-depth aroma analysis. Sensory analysis and electronic nose (E-nose) were used to compare flavour profiles. Volatile components were extracted via liquid–liquid extraction (LLE) with solvent-assisted flavour evaporation (SAFE), analysed by gas chromatography–mass spectrometry (GC–MS) and gas chromatography olfactometry-mass spectrometry (GC-O-MS). The results revealed 145 volatile compounds, predominantly acids, alcohols, ketones and heterocycles, with acids as the most prevalent (ranging from 960.17 to 1231.78 μg/mL). Additionally, 90 aroma-active compounds were identified, notably acetic acid, furfuryl alcohol, 2,3-dimethylpyrazine, lactic acid, phenol, propyl acetate, ethyl propionate and 2(5H)-furanone. Accordingly, a flavour wheel was constructed highlighting dominant volatile components, featuring acidic, alcohol, tangerine peel-like and yeasty aromas. Partial least squares regression (PLSR) analysis showed that the acidity note in SAV positively correlates with acetic acid, isovaleric acid, hexanoic acid, phenethyl alcohol and butyric acid. Understanding the flavour composition of SAV provides vital insight for flavour research and product quality control.

Crocus sativus L., known as saffron, is one of the major crops among ornamental and medicinal aromatic plants. Polyethylene glycol (PEG) 6000 is one of the well-known and efficient simulators used for this purpose. In this study, saffron corms were cultivated in pots containing perlite, and the PEG 6000 solution was applied at 5%, 10% and 15% concentrations. A HS-SPME-GC–MS system was used to elucidate volatiles of saffron flowers, and a total of 28 volatiles was detected. Safranal was measured as the most dominant volatile compound in saffron flowers, and the release of marker volatiles was dramatically increased with the increasing PEG 6000 dosage. Eucarvone was found to be an important ketone compound, Phenethyl alcohol was found to be the most abundant volatile alcohol compound. Additionally, ketones pyrrole, lactone, esters and other sulphurous components increased with PEG 6000 application. According to the morphological observations, decreases were observed in plant dry weight (PDW), plant fresh weight (PFW), corm diameter (CD), daughter corm (DCN), and flower number (FN), between the control plants and those treated with PEG 6000. However, an increase was detected in root number (RN) and root length (RL). Leaf length (LL), on the other hand, increased with a 5% PEG application but decreased with higher concentrations.

Coffee, a popular beverage worldwide, requires thorough quality assessment to ensure its authenticity and meet consumer demands. Traditional methods in the industry are often subjective, expensive, and time-consuming. This study used a compact, portable electronic nose (e-nose) with machine learning models to classify and distinguish between civet and non-civet roasted beans. The polynomial feature extraction method was used to extract important parameters from the sensor response and improve system performance. Classification models like linear discriminant analysis (LDA), logistic regression (LR), quadratic discriminant analysis (QDA), and support vector machines (SVM) were applied to classify the samples. Among these, the LDA model with polynomial features yielded the highest validation and test accuracies, with values of 0.89 ± 0.04 and 0.93, respectively. This was higher than the statistical feature methods, which obtained validation and test accuracies of 0.80 ± 0.07 and 0.87, respectively. The acquired e-nose results were correlated with compound concentrations in roasted coffee beans measured by gas chromatography–mass spectrometry (GC–MS). These findings demonstrate the e-nose system's promising potential to effectively distinguish civet from non-civet roasted coffee beans based on their aroma profiles using polynomial feature extraction methods.

The limited availability of raw materials for cigarette aroma, particularly in emerging spices, highlights the need for proactive research in exploring and utilising new flavours. Pyrrole derivatives are an important class of five membered nitrogen-containing heterocyclic compounds with beautiful aroma and excellent biological activity. By synthesising 2-(2,5-dimethyl-1H-pyrrol-1-yl)-4-methylpentanoic acid using the Paal–Knorr reaction followed by esterification reactions, novel pyrrole ester fragrances (5a and 5b) were obtained for further investigation. The two synthesised compounds were characterised using nuclear magnetic resonance spectroscopy (¹H and ¹³C NMR), infrared spectroscopy (IR) and high-resolution mass spectrometry (HRMS). Furthermore, the thermal properties, smoke transfer behaviour and antioxidant capacity of compounds 5a and 5b were evaluated. Thermogravimetric analysis (TG) revealed that compounds 5a and 5b exhibited major mass loss phases between 124.3°C–450°C and 116.8°C–450°C, respectively, with mass loss rates of 80.58% and 95.45%. Pyrolysis (Py) of compounds 5a and 5b resulted in the formation of eight and nine compounds, respectively. Moreover, the transfer rates of mainstream smoke particles from flavour additives 5a and 5b in tobacco shreds were higher compared with cigarette paper flavouring. Compound 5a demonstrated slightly higher antioxidant activity involving 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radicals (•OH) and superoxide anion ($��·�O_2^{-}�$) than compound 5b. These findings support the development of new tobacco flavours and fragrance components and encourage further practical investigations.

The investigation of the thermal release properties of flavours under heating conditions is essential for their application in related products. Herein, the thermal release processes of six typical aldehyde flavours with different boiling points were evaluated via thermogravimetric-derivative thermogravimetric (TG-DTG) and differential scanning calorimetry (DSC). To further study the relative proportions of prototype evaporation and the pyrolytic products under heating conditions, we developed a temperature-controlled tube furnace combined with thermal release products capturing device to simulate the pyrolysis process of aldehyde flavours under temperature of 350°C and three atmospheres (9%, 21% oxygen and 100% nitrogen), respectively. The TG-DTG curves showed that the selected flavours exhibited different thermal weight loss processes in terms of temperature range, initial release temperature (T_i), temperature at maximum weight loss rate (T_max) and final release temperature (T_f). The T_max of six aldehyde flavours was located between 173.73°C and 269.12°C depending on the thermal stability. Among them, cinnamaldehyde and p-anisaldehyde possessed the lowest and highest comprehensive release index (CRI) values of 1.07 × 10⁻³%/(min × ^oC²) and 9.81 × 10⁻³%/(min × ^oC²), respectively. Meanwhile, DSC analysis showed that all aldehyde flavours exhibited different heat absorption behaviour, and the enthalpy changes ranged from 236.10 to 393.80 J/g. According to the distribution of released pyrolytic products, the selected flavours can be classified as stabilised aldehydes and significantly pyrolytic aldehydes, and the heating atmospheres exhibited an obvious effect on the thermal release behaviour of aldehyde flavours. In addition, the possible pyrolysis schemes of significantly pyrolytic aldehydes were proposed based on the molecular structure.

Intersectional hybrids of Paeonia (Paeonia Itoh hybrids) have rich colours and strong fragrance, combining the advantages of sect. Moutan and sect. Paeonia, and have great economic value and development potential. However, there have been few studies on the floral fragrance components of intersectional hybrids of Paeonia. In this study, the types and contents of volatile components of 20 intersectional hybrids of Paeonia were conducted. A total of 53 floral volatiles were identified though gas chromatography–mass spectrometry (GC–MS) analysis, with linalool, nonanal and phenylethyl alcohol as the main floral components. Based on the compound contents and odour activity values (OAVs) analysis, the 20 cultivars were classified into four aroma types: a floral scent, a fresh floral scent, a floral with spicy scent and a fruity scent. ‘Magical Mystery Tour’ had the highest volatile compound contents and OAVs, and had potential for exploitation. This study provided a theoretical reference for the selection of parents for flower fragrance breeding of Paeonia Itoh hybrids.

Cinnamon is widely recognised for its distinct flavour and potential health benefits, making it an important subject of study in food and nutraceutical fields. To understand the mechanism of cinnamon flavour release as a fundamental step in its flavour perception from high-amylose corn starch microcapsules, the release of cinnamaldehyde under in vitro mouth conditions was studied using a 3D numerical model. Additionally, predicting cinnamaldehyde release in all three phases simultaneously was developed in COMSOL Multiphysics 5.6. To validate the developed model, cinnamaldehyde release profiles were prepared under simulated mouth conditions using headspace analysis by the SPME-GC–MS procedure. High R² (0.997) and low RMSE (1.78E-06) values, along with good convergence results, confirmed this simulation as a precise numerical model. The effects of cinnamaldehyde initial load, cinnamaldehyde diffusivity and shear rate were also probed, revealing the model to be more sensitive to the microcapsules' properties. This study provides a valuable framework for designing controlled release systems for flavouring agents, with significant implications for food and nutraceutical industries.