Regional Variation of Chemical Characteristics in Young Marselan (Vitis vinifera L.) Red Wines from Five Regions of China

Effect of Cluster-Zone Leaf Removal at Different Stages on Cabernet Sauvignon and Marselan (Vitis vinifera L.) Grape Phenolic and Volatile Profiles

This study investigated the effect of leaf removal at three stages of grape development on the phenolic and volatile profiles of Cabernet Sauvignon and Marselan grapevines for two consecutive years in the Jieshi Mountain region, an area of eastern China with high summer rainfall. The results indicated that cluster-zone leaf removal generally reduced the titratable acidity of both varieties, but did not affect the total soluble solids of grape berries. Leaf-removal treatments increased the anthocyanin and flavonol content of berries in both varieties. However, in Cabernet Sauvignon, leaf removal negatively affected the norisoprenoid compounds, with a more pronounced impact observed when the leaf removal was conducted at an early stage. This negative effect may be related to a decrease in the levels of violaxanthin and neoxanthin, potential precursors of vitisprine and β-damascenone. In contrast, the removal of leaves had no effect on the norisoprenoid aroma of Marselan grapes.

Correlation between changes in flavor compounds and microbial community ecological succession in the liquid fermentation of rice wine

Microorganisms play an important role in regulating flavor compounds in rice wine, whereas we often don't understand how did they affect flavor compounds. Here, the relations between flavor compounds and microbial community ecological succession were investigated by monitoring flavor compounds and microbial community throughout the fermentation stage of rice wine. The composition of microbial community showed a dynamic change, but 13 dominant bacterial genera and 4 dominant fungal genera were detected throughout the fermentation stages. Saccharomyces presented a strong negative correlation with fungi genera but had positive associations with bacteria genera. Similarly, flavor compounds in rice wine were also showed the dynamic change, and 112 volatile compounds and 17 free amino acids were identified in the whole stages. The alcohol-ester ratio was decreased in the LTF stage, indicating that low temperature boosts ester formation. The potential correlation between flavor compounds and microbial community indicated that Delftia, Chryseobacterium, Rhizopus and Wickerhamomyces were the core functional microorganisms in rice wine. These findings clarified the correlation between changes in flavor compounds and in microbial community in the liquid fermentation of rice wine, and these results have some reference value for the quality improvement and technological optimization in liquid fermentation of rice wine.

Quality Characteristics and Antioxidant Activities of Six Types of Korean White Wine

The cultivation of European grape cultivars suitable for winemaking in Korea presents challenges due to factors such as climate, soil conditions, precipitation, and sunlight. Consequently, Korea has traditionally resorted to adding sugar to its wine production to counteract the low sugar content in Korean grapes, yielding lower-quality wines. However, recent success in the cultivation of five European grape cultivars and the development of the domestic grape cultivar Cheongsoo have increased the possibility of achieving high-quality Korean wines. This study aimed to explore the potential of European grape cultivars and Cheongsoo as wine grapes in Korea. This study also conducted sensory evaluation and analyzed the physicochemical properties of the grapes and wines, including antioxidant capacity and color. Despite originating from the same vineyard, the composition of grapes and wines, including volatile aromatic compounds, significantly differed among the grape cultivars. In particular, Vidal wine exhibited superior antioxidant capacity compared with other wines. Moreover, Cheongsoo wine showed higher levels of essential volatile aromatic compounds, such as monoterpenes, than other wines. Sensory evaluation of these two wines also revealed excellent results. In conclusion, these findings hold promise for enhancing the diversity of Korean white wine and fostering growth in the wine industry.

Comparison of Chemical and Sensory Profiles between Cabernet Sauvignon and Marselan Dry Red Wines in China

The differences in chemical and sensory characteristics between Marselan and Cabernet Sauvignon in China were investigated with gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-QqQ-MS/MS), combined with color parameters and sensory data. The paired t-test results showed that terpenoids, higher alcohols, and aliphatic lactones were significantly different according to the grape variety. Meanwhile, terpenoids could be considered as marker aroma compounds to distinguish Marselan wines from Cabernet Sauvignon, which could explain the distinct floral note in Marselan wines. The mean concentrations of the mv-vsol, mv-vgol, mv-vcol, mvC-vgol, mv-v(e)cat, mvC-v(e)cat, mv-di(e)cat, and cafA were higher in Marselan wines than Cabernet Sauvignon wines, and these compounds might confer Marselan wines with a deeper color, more red hue, and higher tannin quality. The phenolic profiles of Marselan and Cabernet Sauvignon wines were influenced by the winemaking process, mitigating the varietal differences. As for sensory evaluation, the intensities of herbaceous, oak, and astringency of Cabernet Sauvignon were more pronounced than Marselan, whereas the Marselan wines were characterized by a high color intensity and more redness, together with floral, sweet, and roasted sweet potato attributes, and tannin roughness.

Sub-Regional Variation and Characteristics of Cabernet Sauvignon Wines in the Eastern Foothills of the Helan Mountain: A Perspective from Phenolics, Visual Properties and Mouthfeel

As one of the most promising wine regions in China, the eastern foothills of the Helan Mountain (EFHM) in the Ningxia Hui Autonomous Region has attracted great attention recently. Geographically, EFHM is divided into six sub-regions, namely Shizuishan, Xixia, Helan, Qingtongxia, Yongning and Hongsipu. However, there have been few reports on the character and differences between wines in the six sub-regions. In this experiment, a total of 71 commercial Cabernet Sauvignon wines from six sub-regions were collected, and their phenolic compounds, visual properties and mouthfeel were investigated. The results showed that wines from the six sub-regions of EFHM showed distinctive phenolic profiles and could be distinguished through the OPLS-DA mode using 32 potential markers. In terms of color, Shizuishan wines showed higher a* values and lower b* values. The sensory evaluation showed that Hongsipu wines had higher astringency strength and lower tannin texture. The overall results implied that the phenolic compounds of wines in different sub-regions were affected by terroir conditions. To the best of our knowledge, this is the first time that a wide coverage of phenolic compounds has been analysed for wines from the sub-regions of EFHM, which could provide valuable information in deciphering the terroir of EFHM.

Characterization of key odor-active compounds in Chinese Dornfelder wine and its regional variations by application of molecular sensory science approaches

In this study, aroma characteristics and odor-active compounds in Dornfelder wines from three main production regions of China were comprehensively investigated for the first time. The leading features of Chinese Dornfelder wines were black fruit, violet, acacia/lilac, red fruit, spice, dried plum, honey, and hay based on check-all-that-apply. Wines from the Northern Foothills of Tianshan Mountains and Eastern Foothills of Helan Mountains were dominated by floral and fruity aromas, while wines from the Jiaodong Peninsula were characterized by mushroom/earth, hay, and medicinal material notes. Aroma profiles of Dornfelder wines in three regions were successfully reconstructed with 61 volatiles determined by AEDA-GC-O/MS and OAV. Through aroma reconstitution, omission tests, and descriptive analysis, terpenoids could be regarded as varietal characteristic compounds directly contributing to floral perception in Dornfelder wines. Guaiacol, eugenol, and isoeugenol were further revealed to have a synergistic effect with linalool and geraniol on violet, acacia/lilac, spice, and black fruit.

Volatile Profiles and Sensory Characteristics of Cabernet Sauvignon Dry Red Wines in the Sub-Regions of the Eastern Foothills of Ningxia Helan Mountain in China

To elucidate the effects of the different terroir on wine aroma in six sub-regions of Eastern Foothills of Helan Mountain in Ningxia, a premium wine-producing region in China, 71 Cabernet Sauvignon wines were investigated by gas chromatography-mass spectrometry (GC-MS), check-all-that-apply (CATA), and quantitative descriptive analysis (QDA). The bidirectional orthogonal partial least squares-discriminant analysis (O2PLS-DA) results showed that the Cabernet Sauvignon dry red wines from Xixia (XX) and Yongning (YN) had similar volatile profiles due to their geographical proximity and were characterized by higher concentrations of esters, higher alcohols, and volatile phenols because the similar aromatic profiles were detected in their dry red wines. Shizuishan (SZS) and Hongsipu (HSP) wines showed clear differences compared to the wines of the other four sub-regions, being mainly characterized by relatively higher phenolic aldehydes and volatile phenols. The concentrations of methoxypyrazines and norisoprenoids varied mainly depending on the climate diversity of the sub-regions. The highest 3-isobutyl-2-methoxypyrazine (IBMP) concentration was presented in the Helan (HL) wines. The Qingtongxia (QTX) wines have the highest β-damascenone, which might be influenced by the fact that QTX has the lowest effective accumulated temperature and the highest sunshine duration among the five sub-regions. Esters including ethyl octanoate, ethyl decanoate, ethyl butanoate, ethyl hexanoate, and isoamyl acetate were the highest in HL. Additionally, the herbaceous, black berry, and red berry notes in HL and QTX were the most outstanding.

Stability and Antioxidant Activity of Hydro-Glyceric Extracts Obtained from Different Grape Seed Varieties Incorporated in Cosmetic Creams

Grape seeds are agro-industrial by-products, which if improperly managed, may be responsible for socioeconomic and environmental problems. Nevertheless, it is possible to effectively valorize them by means of extraction of the bioactive compounds, especially the antioxidant phenolic molecules, using a safe, green, and environmentally-friendly extractive medium (i.e., hydro-glyceric solution). In the present study, the extraction was performed using seeds from two Lebanese varieties, Obeidi and Asswad Karech, and three international varieties, Marselan, Syrah, and Cabernet Franc. The type and amount of phenolic compounds were identified by High-Performance Liquid Chromatography (HPLC). Marselan was the extract richer in catechins (132.99 ± 9.81 μg/g of dried matter), and it also contained a higher amount of phenolic compounds (49.08 ± 0.03 mg of gallic acid equivalent/g of dry matter and 10.02 ± 0.24 mg of proanthocyanidin content/g of dry matter). The antioxidant capacity of the extracts was assessed using three different colorimetric assays including 2,2-DiPhenyl-1-PicrylHydrazyl (DPPH), CUPRIC ion Reducing Antioxidant Capacity (CUPRAC), and Ferric Reducing Antioxidant Power (FRAP). As expected, Marselan exhibited the highest antioxidant activity; as well, the total phenolic and proanthocyanidin content were the highest. The stability of the Marselan extract incorporated into a commercial cream, was performed at three different temperatures (4, 25, and 50 °C), and four different concentrations (5, 4, 3, 2%), over a period of 4 months, using different methods such as centrifugation, Heat-Shock Cycles, pH, and viscosity. All Marselan hydro-glyceric extract formulations were proven to be stable over the entire 4 months, where the highest stability was achieved at 4 °C and the least at 50 °C. This study supports the suitability of the incorporation of phenolic extracts into commercial creams to enrich the cosmetic industry with effective, natural, and safe skincare products.

Effect of Commercial Yeast Starter Cultures on Cabernet Sauvignon Wine Aroma Compounds and Microbiota

Commercial Saccharomyces cerevisiae plays an important role in the traditional winemaking industry. In this study, the correlation of microbial community and aroma compound in the process of alcohol fermentation of Cabernet Sauvignon by four different commercial starters was investigated. The results showed that there was no significant difference in the fermentation parameters of the four starters, but there were differences in microbial diversity among the different starters. The wine samples fermented by CEC01 had higher microbial abundance. GC-MS detected a total of 58 aromatic compounds from the fermentation process by the experimental yeasts. There were 25 compounds in the F6d variant, which was higher than in other samples. The PCA score plot showed that 796 and F15 yeast-fermented wines had similar aromatic characteristic compositions. According to partial least squares (PLS, VIP > 1.0) analysis and Spearman’s correlation analysis, 11, 8, 8 and 10 microbial genera were identified as core microorganisms in the fermentation of 796, CEC01, CECA and F15 starter, respectively. Among them, Leuconostoc, Lactobacillus, Sphingomonas and Pseudomonas played an important role in the formation of aroma compounds such as Ethyl caprylate, Ethyl caprate and Ethyl-9-decenoate. These results can help us to have a better understanding of the effects of microorganisms on wine aroma and provide a theoretical basis for improving the flavor quality of Cabernet Sauvignon wine.