Differences In Aroma Research Articles

Comparative analysis of the differences among Langya flavor Baijiu and strong and soy sauce flavor Baijiu by targeted flavor analysis

Jian flavor Baijiu (JFB) is a unique flavor type of Baijiu with the flavor characteristics of both strong flavor Baijiu (SFB) and soy sauce flavor Baijiu (SSFB). Langya flavor Baijiu (LYFB) is a kind of JFB, and its differences in aroma compared to SFB and SSFB were first systematically investigated using targeted flavor analysis. Seventy important odorants were analyzed in LYFB, SFB, and SSFB. The quantitative ratio relationships of 17 skeleton odorants among the three flavor types of Baijiu were explored. In addition, multivariate statistical analysis was used to investigate the differences in the odorant composition among the three flavor types of Baijiu. Hexanoic acid, ethyl acetate, ethyl hexanoate, ethyl lactate, butanoic acid, 2-methylbutanal and ethyl butanoate were all first identified as important markers in JFB and SFB. Fourteen odorants were all first identified as important markers in JFB and SSFB, such as acetic acid and ethyl hexanoate. This study is of great significance to the technological improvement and quality stability of JFB.

Effects of degree of milling on nutritional quality, functional characteristics and volatile compounds of brown rice tea.

This study investigated the effects of rice preparation using different degrees of milling (DOM) from 0% to 13% on the nutritional composition, functional properties, major volatile compounds and safety of brown rice tea (BRT). We found that 2% DOM reduced 52.33% of acrylamide and 31.88% of fluorescent AGEs. When DOM was increased from 0% to 13%, the total phenolic content (TPC) of brown rice tea decreased by 48.12%, and the total flavonoid content (TFC) and condensed tannin content (CTC) also decreased significantly, with the smallest decrease at 2% DOM. In addition, the inhibitory activities of α-amylase, α-glucosidase and pancreatic lipase as well as the antioxidant activity also decreased gradually. Analysis by electronic nose and gas chromatography-mass spectrometry (GC-MS) showed that alkanes, furans, aldehydes, pyrazines and alcohols were the major volatiles in BRT, with 2% DOM having the greatest retention of aroma compounds. An orthogonal partial least squares discriminant analysis (OPLS-DA) and VIP score (VIP > 1 and p < 0.05) analysis were used to screen 25 flavor substances that contributed to the differences in BRT aroma of different DOMs. These results suggest that 2% milled BRT can improve safety and palatability while maximizing the retention of flavor compounds and nutrients. The findings of this study contribute to an enhanced understanding of the dynamics of changes and preservation of aroma compounds and nutrients present during the processing of BRT.

Characterization of the Key Aroma Compounds in Different Yeast Proteins by GC-MS/O, Sensory Evaluation, and E-Nose.

The unique odors of yeast proteins (YPs) are decisive for their application in meat substitutes. Sensory evaluation, electronic nose, and gas chromatography-mass spectrometry/olfactory (GC-MS/O) were combined to characterize the aroma profiles and aroma-active compounds of YPs. The sensory evaluation results indicate that the sweaty aroma had the strongest intensity in YP #10, followed by rice bran, sour, and plastic. The electronic nose could effectively distinguish the aroma differences among five YPs. A total of 27 aroma-active compounds in the five YPs were identified by GC-MS/O. The concentration of 2-methyl-propanoic acid (6.37 μg/kg), butanoic acid (47.46 μg/kg), 3-methyl-butanoic acid (22.50 μg/kg), and indole (943.40 μg/kg) in YP #10's aroma was higher than that of the other YPs. The partial least squares regression method results show that o-cresol, (3S)-3,7-dimethyloct-7-en-1-ol, benzyl alcohol, octanal, 2-methyl-propanoic acid, butanoic acid, 3-methyl-butanoic acid, hexanal, heptanal, and indole were predicted as the potential aroma-active compounds significantly contributing to the aroma profiles of the five YPs. Addition experiments confirmed that the overall aroma profile intensities of the five YP samples were extended with the addition of these ten compounds, verifying their significant contributions.

A Comparative Analysis of the Flavor, Aroma, and Compositions in Three Levels of Stir-Frying Cyperus rotundus Using E-Tongue, E-Nose, and HS-GC-MS

Cyperus rotundus (CR) is the dry rhizome of the Cyperaceae plant Cyperus, which is widely used in food processing, such as curry, pickling spices, and baking goods, as well as medicinally after stir-frying. The level of stir-frying (slightly stir-frying, stir-frying yellow, and stir-frying black) has a direct impact on the flavor, aroma, and pharmacological effects of the food. However, the distinctions between various levels of stir-frying have not been studied. The purpose of this study was to develop a method that combines electronic tongue, electronic nose, and HS-GC-MS to elucidate the flavor and aroma differences between three types of stir-fried CR and to identify aroma difference components. As the degree of stir-frying increased, the sweet, bitter, astringent, and umami flavors of the sf-CR diminished while the aroma intensified. Among the 33 differential compounds, pyrazines, D-limonene, camphene, trans-verbenol, and ponocarvone were the most significant aroma-causing components. This method effectively differentiates the three levels of sf-CR and provides a foundation for the use of sf-CR in food processing and pharmaceutical applications.

Difference in Volatile Aroma Components of Stropharia rugosoannulata under Two Cultivated Environments Investigated by SPME-GC-MS.

In order to study the effect of both greenhouse and forest cultivating environments on Stropharia rugosoannulata, its volatile aroma compounds were measured by a headspace solid phase micro extractions-gas chromatograph-mass spectrometer (SPME-GC-MS). The optimal adsorption temperature was 75 °C and the optimal adsorption time was 40 min. A total of 36 volatile aroma compounds were identified by GC-MS, including 8 aldehydes, 2 ketones, 4 alcohols, 15 alkenes, and 4 alkanes. Hexanal, 3-Octanone, 2-Undecanone, (E)-Nerolidol, and (Z)-β-Farnesene made great aromatic contributions. Among them, Hexanal, 3-Octanone, 2-Undecanone were the key aroma compounds for which odor activity values (OAVs) were more than 1. (E)-Nerolidol showed odor modification in the forest samples and showed a key aroma effect in greenhouse samples. (Z)-β-Farnesene showed odor modification in greenhouse samples. 3-Octanone was the largest contributing compound for which the OAV was more than 60. The total content of volatile aroma compounds first increased and then decreased with growth time; it reached the highest level at 48 h: 2203.7 ± 115.2 μg/kg for the forest environment and 4516.6 ± 228.5 μg/kg for the greenhouse environment. The aroma was the most abundant at this time. All samples opened their umbrella at 84 h and become inedible. Principal component analysis (PCA), hierarchical cluster analysis (HCA), and orthogonal partial least squares discriminant analysis (OPLS-DA) were combined to analyze the aroma difference of S. rugosoannulata under two cultivation modes. PCA and HCA could effectively distinguish the aroma difference in different growth stages. Under different culturing methods, the aroma substances and their changes were different. The samples were divided into two groups for forest cultivation, while the samples were divided into three groups for greenhouse cultivation. At the end of growth, the aroma of S. rugosoannulata with the two cultivation modes was very similar. OPLS-DA clearly distinguished the differences between the two cultivation methods; 17 key aroma difference factors with variable importance projection (VIP) > 1 were obtained from SPLS-DA analysis.

Comparative Physical and Organoleptic Properties, Nutritional Composition, and Safety of Charcoal and Oven Smoked Noiler Meat Spiced Asun.

Five Matured Noiler chickens 3 months old weighing 3kg±120g were used for the experiment. The birds have fasted for 16 hours without food but with a supply of fresh cool water. The birds were slaughtered and dressed conventionally. The breast meat was excised within one-hour post-mortem and used for the preparation of Asun using charcoal and oven smoking. The breast meats were cut into fillets of average weight without bone; the fillets were spiced, rubbed with vegetable oil, and smoked using charcoal and oven to an internal temperature of 720C for 20 minutes with regular turning. The result shows a significant difference (p&lt;0.05) in the nutritional and chemical composition of raw and smoke Noiler meat. The charcoal and oven-smoked Asun were not different, but both differ from the raw. The organoleptic properties show no significant difference (p&gt;0.05) in color, aroma, and texture while flavor, juiciness, and overall acceptability differ. There was a significantly different (p&gt;0.05) in WHC, cooking loss, and cooking yield. Preparation of Asun using charcoal and oven smoking contributed to the nutritional component except for the moisture content. The cholesterol, SFA, MUFA, PUFA, and amines were also increased. The value obtained shows that charcoal and oven-smoked Noiler meat Asun is safe for consumption and has no negative effect, also impacts positively on both the physical and organoleptic properties of the prepared product and therefore, recommended for the preparation of Asun using Noiler meat.

Aroma Identification and Classification in 18 Kinds of Teas (Camellia sinensis) by Sensory Evaluation, HS-SPME-GC-IMS/GC × GC-MS, and Chemometrics.

Tea (Camellia sinensis) is one of the most popular beverages worldwide. Many types of tea products continuously emerge in an endless stream; so, the classification of tea becomes more difficult. Aroma is a vital indicator of tea quality. The present study deals with the identification of aroma compounds in 18 different kinds of tea belonging to three typical tea varieties, including green tea, oolong tea, and black tea, using GC-IMS and GC × GC-O-MS. Moreover, the clustering of all 18 tea samples and the in depth correlation analysis between sensory evaluation and instrumental data were performed using the PCA and OPLS-DA. The results revealed that in all 18 kinds of tea, a total of 85 aroma compounds were detected by GC-IMS, whereas 318 were detected by GC × GC-O-MS. The PCA result revealed that green tea, oolong tea, and black tea could be clearly separated based on their peak areas. The OPLS-DA result showed that a total of 49 aroma compounds with VIP value > 1.0 could be considered as the potential indicators to quickly classify or verify tea types. This study not only compared the aroma differences across different types of teas, but also provided ideas for the rapid monitoring of tea quality and variety.

Analysis of Important Volatile Organic Compounds and Genes Produced by Aroma of Pepper Fruit by HS-SPME-GC/MS and RNA Sequencing.

Pepper is an important condiment, and its aroma affects its commercial value. In this study, transcriptome sequencing and combined headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to analyze the differentially expressed genes and volatile organic compounds in spicy and non-spicy pepper fruits. Compared with non-spicy fruits, there were 27 up-regulated volatile organic compounds (VOCs) and 3353 up-regulated genes (Up-DEGs) in spicy fruits. The results of KEGG enrichment analysis of the Up-DEGs combined with differential VOCs analysis showed that fatty acid biosynthesis and terpenoid biosynthesis may be the main metabolic pathways for aroma differences between non-spicy and spicy pepper fruits. The expression levels of the fatty acid biosynthesis-related genes FAD, LOX1, LOX5, HPL, and ADH and the key terpene synthesis gene TPS in spicy pepper fruits were significantly higher than those in non-spicy pepper fruits. The differential expression of these genes may be the reason for the different aroma. The results can provide reference for the development and utilization of high-aroma pepper germplasm resources and the breeding of new varieties.

Pengaruh penambahan tepung kulit ari kedelai dan tepung wortel terhadap sifat fisikokimia dan sensori mie kering [Effect of the soybean husk and carrot flour addition on the physicochemical and sensory properties of dry noodles

Noodles are generally made from wheat flour which is only high in carbohydrates. Meanwhile, noodle products are needed sholud have others nutritional compound that can be used as daily needs consumption. One of them is the utilization of soybean husk which has been only discardes or used as animal feed. The utilazation of soybean husk waste has not been widely used for the food products. Noodles product can be susbtituted for carrots which are rich ini vitamins and carotenoids. Between of them can be substituted into noodle product proccesed. The purpose of this study was to analyze dry noodle products on the effect of soybean epidermis and carrot flour addition on physicochemical and sensory properties. These dry noodles could be used for a healthy menu as an alternative to carbohydrates in rice. There are some previous study about the effect of soybean husk added to the making of biscuit and cookies products that increase status of nutrition, however it was rarely utilized to substitute on the noodle making. Hence, the aim of this study were to utilize of the soybean husk and to analyze dry noodle products on the effect of soybean husk and carrot flour addition on physicochemical and sensory properties. The method of this study was carried out using quantitatve descriptive with prameters analyzed were moisture content, rehydration power, swelling power, and elasticity as well assensory. While the sensory data were examined by the Kruskal Wallis test. The physicochemical analysis properties test results showed that significant differences in rehydration power, swelling power, and water content, while the product elasticity showed no significant difference. The rehydration power, swelling power, elasticity,and water content showed that 86.67-133.34%;10-20%; 29.80-48.21% and1.19-1.95%, respectively. Furthermore, the sensory test results showed that there were significant differences in aroma and taste, while no significant differences in color and texture. The evaluation sensory of color and texture showed sig&gt;α (0.88&gt;0.05; 0.62&gt;0.05), it mean that there was no difference, while in aroma and taste there were differences with sig&lt;α (0.01&lt;0.05). It can be concluded that the addition of soybean husk and carrot flour had an effect on the chemicals and organoleptic properties of dry noodle. To distguise the aroma of soybean husk other ingredients such as ginger or can be added. Hence,, the further research was necessary conducted in order to obtain strongly attractive color and aroma in dry noodle and to get rid of the unpleasant aroma optimally.

The Interaction Relationship of Aroma Components Releasing with Saliva and Chewing Degree during Grilled Eels Consumption.

The interaction perception between aroma and oral chewing during food consumption has always been a hot topic in exploring consumers' preferences and purchase desires. A chewing simulation system was set to find out the effect of key saliva components and chewing time on odorants released with grilled eel meat. Odor release did not always enhance with the degree of chewing, or the amount of saliva released. The breaking up of the tissue structure of the fish meat by the teeth encourages the release of odorants and the participation of saliva partially blocks this process. The release of pyrazine, alcohol, and acid compounds in grilled eel meat peaked within 20-60 s after chewing. Sufficient exposure of saliva to grilled eel meat will inhibit aromatic, ketone, ester, hydrocarbon, and sulfur compounds release. 3-methyl-2-butanol contributed to the subtle aroma differences that arise before and after eating grilled eel meat. Naphthalene, 2-acetylthiazole, 2-decenal, 2-undecanone, 5-ethyldihydro-2(3H)-furanone were the main odorants released in large quantities in the early stages of eating grilled eel and affected the top note. Consequently, the results provided the odorants information in aroma perception during grilled eel consumption and benefited the objective evaluation of grilled eel product optimization.

Effects of Different Probiotics on the Volatile Components of Fermented Coffee Were Analyzed Based on Headspace-Gas Chromatography-Ion Mobility Spectrometry.

Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to study the effects of four kinds of probiotics on the volatile components of fermented coffee. The fingerprints showed that 51 compounds were confirmed and quantified, including 13 esters, 11 aldehydes, 9 alcohols, 6 ketones, 3 furans, 5 terpenes (hydrocarbons), 2 organic acids, 1 pyrazine, and 1 sulfur-containing compound. After fermenting, the aroma of the green beans increases while that of the roasted beans decreases. After roasting, the total amount of aroma components in coffee beans increased by 4.48-5.49 times. The aroma differences between fermented and untreated roasted beans were more significant than those between fermented and untreated green beans. HS-GC-IMS can distinguish the difference in coffee aroma, and each probiotic has a unique influence on the coffee aroma. Using probiotics to ferment coffee can significantly improve the aroma of coffee and provide certain application prospects for improving the quality of commercial coffee beans.

The Additions Of Telang Flower Extraxtc Towards Quality Of Goat Milk Ice Cream

The background of this research is that the telang flower extract is not optimal for use in food processing. Telang flower extract can be an alternative as an additive in making ice cream. This study aims to analyze the effect of adding telang flower extract with a treatment of 0%, 20%, 30%, 40%. Regarding the quality of color, aroma, texture and taste. This type of research is a pure experiment using a completely randomized design method. Three repetitions were carried out with 3 expert panelists in the Culinary Workshop of the Department of IKK, FPP, UNP. The dependent variable (Y) is the quality of the ice cream. The instrument used was an organoleptic test through a level test, using ANOVA statistics and if it was significantly different it was continued with Duncan's test. The results showed that there was a significant effect on color quality. Meanwhile, there is no significant difference in aroma, taste and soft texture. It can be concluded that the best percentage is found in the addition of 40% telang flower extract to the quality of goat's milk ice cream.

From Hop to Beer: Influence of Different Organic Foliar Fertilisation Treatments on Hop Oil Profile and Derived Beers' Flavour.

Foliar fertilisation is known to influence the physiological response of Humulus lupulus (hop plants), but its effect on the flavour profile of beer still has to be investigated. By comparing the effects of four fertilisation treatments, this study aims at determining whether different foliar fertilisation treatments have a significant impact on hop plants' aromatic quality and that of the beer produced. Hop cones harvested from each experimental treatment were brewed to obtain five single dry-hopped beers, which were subsequently analysed. Gas chromatography-mass spectrometry (GC-MS) and electronic nose (Cyranose 320) analyses were performed on the hop cones, while headspace solid-phase microextraction-gas chromatography-mass spectrometry HS-SPME-GC-MS, electronic nose and sensory analyses were carried out on the beers produced. The analyses not only allowed for a differentiation between the hops from the four fertilisation treatments and the control but also enabled a differentiation between the beers produced for their identification. Sensory evaluation revealed consumer preferences regarding the dry-hopped beers analysed, evidencing their distinctive features, including significant differences in both aroma and flavour.

Organoleptic Quality of Cereal Based on Sago Flour with a Combination of Red Spinach Flour for Patients with Diabetes Mellitus

This study aims to determine the organoleptic quality of cereals based on sago flour with a combination of red spinach flour for diabetics. This type of research is an experiment using a completely randomized design (CRD) with 3 treatments and 6 repetitions. Observations were made by means of organoleptic quality tests. The panelists used were somewhat trained panelists of 30 people. Data were analyzed using the Kruskal Wallis test. The results showed that the red color was close to brownish red (2.3–3.67). Sago flavor (2.47–2.73) and spinach flavor (2.26–2.53). Not sweet (1.07–1.37), sago flavor (2.17–2.4), and spinach flavor (1.93–2.1). Crispy in texture close to very crunchy (2.93–3). Has a difference in color and does not have a difference in aroma, taste and texture. The conclusion is that the red color is close to brownish red. Scented sago and scented spinach. Not sweet, sago and spinach taste. Crispy in texture close to very crunchy, and the color parameters have differences

Study on the Effects of Processes on Aroma Compounds in Rizhao Green Tea Based on the Gas Chromatography-Ion Mobility Spectrometry

Tea processing plays an important role in the formation of tea aroma. In order to explore the composition and variation in aroma during Rizhao green tea processing, gas chromatography-ion mobility spectrometry was employed to investigate the formation and changes of tea aroma in four processing stages. A total of 62 volatile compounds were identified, including alcohols, aldehydes, ketones, esters, terpenes, and oxygen compounds. Relative odor activity value was used to identify 17 characteristic aroma compounds. The main aromatic compounds of chestnut-like aroma were linalool, pentanal, hexanal, heptanal, octanal, nonanal, 2-methylbutanal, 3-methylbutanal, 3-methylthiopropanal, and methyl 2-methylbutanoate. There were significant changes in the volatile components at different processing stages. Samples of tea leaves and green tea had special aroma characteristics, while samples of fixated and rolled leaves had similar aroma compounds. The results are beneficial for the improvement of the flavor and quality of Rizhao green tea. Practical Application. Tea is the world’s most consumed nonalcoholic beverage, with a multitude of health-promoting benefits, such as antioxidant, antiobesity, and antiallergic activities. At present, the research on the aroma compounds of Rizhao green tea mainly focuses on the aroma characteristics of finished tea and the aroma differences of different kinds of commercial tea. This study explored the effects of the processes on aroma compounds, and the results provide a theoretical reference for the improvement of tea processing technology, tea quality control, and evaluation methods.

Assessment and Characterization of Residual Concentrations from Some Cook-in Food Packages Utilized in Nigeria – ‘Moi-Moi’: A Case Study

Aim: To assess the magnitude and safety of migrants from three cook-in food packaging materials (plantain leaf, polyethylene film and aluminium foil) into cooked ‘moi-moi’.&#x0D; Methodology: The ‘moi-moi’ was prepared, packaged in three different packaging materials and cooked to doneness. Analyses of possible migrants from the packaging materials were carried out using standard methods. Raw ‘moi-moi’ paste and cooked ‘moi-moi’ samples were analysed for migrants from associated packaging material on day zero and day 3 of frozen storage. Proximate composition and sensory evaluation as affected by the packaging materials were also conducted. Data obtained were analyzed using two-way analysis of variance (ANOVA) and the means separated by Duncan's New Multiple Range Test (DNMRT).&#x0D; Results: Results obtained showed that the heavy metals originally present in the aluminium foil and plantain leaf gained entrance into the cooked ‘moi-moi’ and the same was the pesticide residue from the plantain leaf. Phthalates and some volatile organic compounds were found to migrate from polyethylene film into the cooked ‘moi-moi’. The proximate compositions showed that the ‘moi-moi’ cooked in plantain leaf had the highest value in ash (9.14%), fibre (3.95%) and protein (21.41%) followed by that in aluminium foil with 6.47% in ash and 1.34% in fibre. The sensory results showed no significant differences in taste, after taste perception, mouthfeel and general acceptability among the ‘moi-moi’ samples cooked in the different packaging materials on day O (the day ‘moi-moi’ was cooked). Nonetheless, on day 3 (3 days frozen storage), significant differences in appearance, mouthfeel, aroma, and general acceptability of the ‘moi-moi’ samples existed except in after taste perception.&#x0D; Conclusion: The concentrations of all the migrants were found to increase with increase in contact time but were all below the safety limits stipulated by WHO, Codex Alimentarius and JECFA even on day 3 of frozen storage.

Comparison of the Aroma-Active Compounds and Sensory Characteristics of Different Grades of Light-Flavor Baijiu.

This study comprehensively characterized and compared the aroma differences between four different grades of Fenjiu (FJ, the most representative light-flavor Baijiu). Aroma-active compounds were analyzed by liquid-liquid extraction (LLE) coupled with gas chromatography-olfactometry-mass spectrometry (GC-O-MS). A total of 88 aroma-active compounds were identified, and 70 of them were quantified. The results showed that a majority of aroma compounds in high-grade FJ had higher aroma intensities and concentrations. Among these compounds, there were 28 compounds with odor activity values (OAVs) greater than one in all four wines, which indicated that they might contribute to the characteristic aroma of FJ. Temporal dominance of sensation (TDS) and quantitative descriptive analysis (QDA) were used to characterize the sensory differences. The results suggested that high-grade FJ had a rich, pleasant and lasting retronasal aroma perception and exhibited pleasant orthonasal aroma of floral, fruity, sweet and grassy. Partial least squares regression (PLSR) analysis effectively distinguished four kinds of FJ and revealed associations between the orthonasal aroma attributes and the aroma compounds with OAVs >1. There were 15 compounds with variable importance in projection (VIP) values >1, and they were considered potential aroma markers for quality prediction.

Characterization of aroma differences on three drying treatments in Rucheng Baimao (Camellia pubescens) white tea

Rucheng Baimao (Camellia pubescens) is an excellent raw material for manufacturing white tea. Drying is the last step in white tea processing and is essential for white tea's aroma. In this study, aroma sensory evaluation combined with volatile compound analysis reveals the characteristic aroma differences of Rucheng Baimao white tea with oven drying (OD), air drying (AD), and sun drying (SD) treatments. Sensory results showed that OD samples had a stronger floral and grassy aroma, AD samples exhibited a more pronounced fresh and pekoe aroma, and SD samples exhibited a unique sunshine odor. Thirty compounds were screened as differential aroma-active compounds of the aroma difference of Rucheng Baimao white tea with three drying treatments using multivariate statistical analysis and relative odor activity value (ROAV ≥1) analysis. The weighted correlation network analysis of the differential compounds revealed the potential association between volatiles and aroma. The results showed that 17 compounds (such as hexanal and p-cymene) were significantly positively correlated with the grassy aroma and 21 compounds (such as linalool and benzeneacetaldehyde) were significantly positively correlated with the floral aroma. Most of these compounds were abundant in OD samples, contributed to its aroma characteristics.

Volatile secondary metabolome and transcriptome analysis reveals distinct regulation mechanism of aroma biosynthesis in Syringa oblata and S. vulgaris

Lilacs have high ornamental value due to their strong aroma. However, the molecular regulatory mechanisms of aroma biosynthesis and metabolism in lilac were largely unclear. In this study, two varieties with distinct aroma, Syringa oblata ‘Zi Kui’ (faint aroma) and Syringa vulgaris ‘Li Fei’ (strong aroma), were used for exploring the regulation mechanism of aroma difference. Via GC-MS analysis, a total of 43 volatile components were identified. Terpene volatiles was the most abundant volatiles constituting the aroma of two varieties. Notably, 3 volatile secondary metabolites were unique in ‘Zi Kui’ and 30 volatile secondary metabolites were unique in ‘Li Fei’. Then, a transcriptome analysis was performed to clarify the regulation mechanism of aroma metabolism difference between these two varieties, and identified 6411 differentially expressed genes (DEGs). Interestingly, ubiquinone and other terpenoid-quinone biosynthesis genes were significantly enriched in DEGs. We further conducted a correlation analysis between the volatile metabolome and transcriptome and found that TPS, GGPPS, and HMGS genes might be the key contributors to the differences in floral fragrance composition between the two lilac varieties. Our study improves the understanding in the regulation mechanism of Lilac aroma and would help improve the aroma of ornamental crops by metabolic engineering.

Characterization of meat quality traits, fatty acids and volatile compounds in Hu and Tan sheep.

Sheep breed has a major influence on characteristics of meat quality and intramuscular fat (IMF), however, studies into the relationship between sheep breed and meat quality traits rarely consider the large variation in IMF within breed. In this study, groups of 176 Hu and 76 Tan male sheep were established, weaned at 56 days old, with similar weights, and representative samples were selected based on the distribution of IMF in each population, to investigate variations in meat quality, IMF and volatile compound profiles between breeds. Significant differences were observed in drip loss, shear force, cooking loss, and color coordinates between Hu and Tan sheep (p < 0.01). The IMF content and the predominate unsaturated fatty acids, oleic and cis, cis-linoleic acids, were similar. Eighteen out of 53 volatile compounds were identified as important odor contributors. Of these 18 odor-active volatile compounds, no significant concentration differences were detected between breeds. In another 35 volatile compounds, γ-nonalactone was lower in Tan sheep relative to Hu sheep (p < 0.05). In summary, Tan sheep exhibited lower drip loss, higher shear force values, and redder color, had less saturated fatty acids, and contained less γ-nonalactone against Hu sheep. These findings improve understanding of aroma differences between Hu and Tan sheep meat. Graphical Abstract.