Geographic Classification of Chinese Grape Wines by Near-Infrared Reflectance Spectroscopy

Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mode in the wavelength range of 800-2500 nm. Wines (n=90) were randomly split into two sets, calibration set (n=54) and validation set (n=36). Discriminant analysis models were developed using BP neural network and discriminant partial least-squares discriminant analysis (PLS-DA). The prediction performance of calibration models in different wavelength range was also investigated. BP neural network models and PLS-DA models correctly classified 100% of the wines in calibration set. When used to predict wines in validation set, BP neural network models correctly classified 100%, 81.8%, and 90.9% of the wines from Changli, Huailai, and Yantai respectively, and PLS-DA models correctly classified 100% of all samples. The results demonstrated that NIRS could be used to discriminate Chinese grape wines as a rapid and reliable method.

Isolation and Identification of Saccharomycetes in Wine Grape Region of Chateau Changyu Moser XV

Objective] This study was conducted to further explore the diversity of Saccharomyces cerevisiae_from Chateau Changyu Moser XV and realize better de-velopment and utilization of Saccharomyces cerevisiae resources. [Method] ln this study, the wine grape regions of Chateau Changyu Moser XV were taken as the research object. The Saccharomycetes_in the soil was isolated, screened and ob-served in the natural fermentation process of grape berry epidermis and the fruit. The 32 Saccharomycetes strains were preliminarily classified based on WL nutrient agar, and 26S rDNA D1/D2 sequence analysis was conducted. [Result] Total y, 4 kinds of Saccharomycetes were identified in this study, including Pichia kluyveri, Hanseniaspora uvarum, Saccharomyces cerevisiae_and Cryptococcus magnus. [Con-clusion] The main species of Saccharomycetes in the wine grape region of Chateau Changyu Moser XV were preliminarily determined, which provides theoretical basis and research basis for the brewing of wine with special characteristics.

Effects of Grape Balanced Nutrition Fertilizer on Yield and Quality of Wine Grapes

In this study,the wine grapes balanced nutrient fertilizer(BNF)was designed according to the wine grape nutritional requirements in different growth stages,and objected to reduce fertilizer application rate of wine grape cultivation,improve fertilizer utilization rate,achieve stable yield and improve the quality of wine grapes.The experiment was carried out at the Great Wall Sanggan Winery,and the Aristocratic Winery.The experiment was designed with two treatments:Namely BNF treatment,and the traditional fertilization(CK).We investigated the effects of BNF on the quality of wine grapes by examining the plant traits of wine grapes in different experimental areas during the growing season,the fruit traits at maturity,and determined the contents of VC,organic acids,amino acids,flavonoids,soluble total sugars,soluble solids,tannins,total phenols and catechins.The results show that:①The application of grape BNF greatly reduced the application amount of nitrogen,phosphorus and potassium,while the vine had no fertilizer deficiency phenomenon;②It increased the single fruit weight,the ear weight and yield to varying degrees,and the yield increase range was between 12% and 41%;③The wine grapes with BNF had the following characteristics:tight infructescence,even color,small fruit less,no fruit dropped,strong fruit colloid feeling,better aroma and taste;④It greatly improved the quality of wine grapes,and increased the content of soluble solids,soluble total sugar,organic acids,VC,total phenols,flavonoids,amino acids and tannins in fruits;⑤It greatly increased the total catechin content of"Riesling"and"Syrah",and had no significant effects on the catechin content of"Merlot"and"Cabernet Sauvignon".In summary,the application of grape BNF has certain practical significance for guiding the production of local wine grapes,ensuring the yield while improving the quality,increasing the income and reducing the environmental pollution caused by excessive fertilization.

Anthocyanin Profiles in Grape Berry Skins of Different Species ofWine Grapes in Shanxi,China

To understand the anthocyanin characteristics of wine grape varieties,the anthocyanin composition and content of 31 wine grape varieties were analyzed to explore the use of anthocyanins as chemical fingerprints to distinguish varieties.Results showed that a total of 21 anthocyanins were detected in the skins,including cyanidin,delphinidin,petunidin,peonidin and malvidin 3-monoglucosides(or 3,5-diglucosides)along with the corresponding acetyl and p-coumaroyl derivatives.The highest and lowest total amount of anthocyanins were detected in‘Ruby Cabernet’and‘Muscat Rouge’,respectively.In the 21 Vitis vinifera grapes,there were 3~11 monoglucoside anthocyanins detected,however,there were 4 to 9 monoglucoside anthocyanins and 1~7 diglucoside anthocyanins detected in the 10 other species of grapes.Except for‘Zhesexiang’‘Seibel Noir’,‘44-6-7-1’and‘Beibinghong’,the contents of diglucoside anthocyanins in the other six varieties accounted for more than 52%of the total anthocyanins.Except for‘Zhesexiang’,‘Muscat Rouge’and‘Beibinghong’,the content of methylated anthocyanins accounted for more than 75%of total anthocyanins.There were significant differences in the anthocyanin types and contents in the skins among V.vinifera and other grapes.The results of the principal component analysis and the cluster classification of 31 grape varieties(lines)were nearly consistent,which suggested that anthocyanins can be used as chemical fingerprints to distinguish wine grape varieties.

Terroir Suitability Zoning for the Six Prevailing Wine Grape Varieties in Ningxia Hui Autonomous Region(with a Focus on the Helan Mountain East) of China

Terroir plays an important role in wine grape production and good wine making.Among all the aspects of terroir in a given region,climate,soil and variety are the most important ones.The goal of this study was to evaluate these three aspects of terroir in Ningxia Hui Autonomous Region of China,with a focus on the Helan Mountain East.Based on historical weather data during the period 1981 to 2016 from 22 meteorological stations in the research area,the climatic indices were derived,with which the growable zone for wine grape cultivation in the research area was identified.By synthesizing the climatic indices and soil type data,stepwise and optimization methods were used to divide the growable zone into optimal,suitable,near-suitable and unsuitable zones for the six prevailing wine grape varieties.In the analysis,the six prevailing wine grape varieties include two white wine grape varieties of“Chardonnay”and“Riesling”and four red wine grape varieties of“Cabernet Sauvignon”,“Merlot”,“Pinot Noir”and“Grenache Noir”.With the Geographic Information System(ArcGIS)software,the geographical distributions of these terroir suitability zonings were mapped in the research area according to a small grid simulation model.The results showed that the growable zone for wine grapes was mainly focused in most of the northern and central parts of Ningxia Hui Autonomous Region.This particular zone was suitable for the typical red wine varieties like late-maturing“Grenache Noir”,medium-to-late maturing“Cabernet Sauvignon”,medium-maturing“Merlot”and early-maturing“Pinot Noir”.In particular,the optimal zone for these four red wine varieties was centered in Xixia county of Yinchuan city,Pigeon Hill of Qingtongxia city and Baima Township of Zhongning County.For the two early-to-medium maturing white wine varieties of“Riesling”and“Chardonnay”,the optimal and suitable zones were in the cool area of the central arid zone and the Qingshui River tributary.

Evaluation of Some New Wine Grape Cultivars under S^o Francisco Valley Conditions

This study aimed to evaluate the performance and characteristics of the grapes as subsidies to the recommendation of new wine grape cultivars for the S^o Francisco Valley. An experiment was carried out in Petrolina, Pernambuco state, during four seasons in 2014 and 2015 and the treatments were represented by 10 cultivars and three breeding selections： Grenache, Tempranillo, Merlot, Cabernet Sauvignon, Malbec, Petit Verdot and Syrah for red wines and Sauvignon Blanc, Chardonnay, Chenin Blanc and breeding selections 46, 14 and 47 for white wines. The experimental design was a randomized block with four replicates and two useful plants per plot. The following variables were evaluated： sprouting, bud fertility rate, Ravaz index, production, number of clusters, weight, length and width of cluster, weight and volume of 100 berries, soluble solids and titratable acidity. A better balance between production and vigour was obtained in Grenache, Merlot and Tempranillo cultivars, presenting values of 7.56, 6.50 and 5.93, respectively, for Ravaz index. Grenache, Chenin Blanc and Tempranillo were the most productive cultivars with average yields estimated at 10.4, 8.7 and 8.4 ton/ha/season. Selection 14 had longer, wider and less compact clusters, which can reduce clusters rottenness. The percentage of sprouting ranged from 38.13% in selection 14 to 77.6% in cv. Chenin Blanc. The average index of bud fertility was 0.79 cluster/bud, with no significant differences among cultivars. Greater potential for sugar accumulation was found in the selections 14, 46 and 47, while the titratable acidity ranged from 0.63% in cv. Merlot to 0.89% in selection 47. Grenache and Tempranillo have showed potential to obtain adequate yield and balanced vines, while Sauvignon Blanc, Chardonnay, Cabemet Sauvignon, Malbec and Petit Verdot presented low yield being necessary to select clones more productive and well adapted to the tropical conditions. Further information about the quality of grapes and wines should be added to these results to allow the recommendation of new cultivars or breeding selections of wine grapes for the Sao Francisco Valley.

On the Status quo and Development Trends of Imported Grape Wine in China

At the present stage, The imported grape wine in China have hot market, imports increased year by year, high gross mar-gins, many brands, uneven quality, low market confidence, the price value of large deviations, imperfect legislation, regulatory confusion and so on characters. The relevant departments and units should actively take a number of measures to improve the market of imported grape wine stably and healthy development. Believe in the future, its imports would continue to grow, the gross profit margin gradually would return to rational, the cost-effective products would be prevailing, the sales channels would be diversification, the enterprises in-volved would increase, and the industry competition would become increasingly fierce.

Effects of leaf removal and cluster thinning on berry quality of Vitis vinifera cultivars in the region of Weibei Dryland in China

Leaf removal and cluster thinning were carried out prior to veraison to evaluate the effects on berry quality of two Vitis vinifera cultivars（Cabernet Sauvignon and Ugni Blanc） in the Weibei Dryland of China in 2013 and 2014, and comprehensive analysis of the chemical and volatile composition in berries was performed. The results showed that content of reducing sugar in both varieties was not affected while total acid was generally decreased by leaf removal and cluster thinning. The pH of berry juice was correspondingly higher in most treatment groups. Meanwhile, promoting effects on accumulation of total phenols, tannin in both varieties and total anthocyanins in Cabernet Sauvignon were found. As for monomeric anthocyanins, percentage of malvidin and its derivatives was decreased by leaf removal and cluster thinning. Besides, cinnamylated anthocyanins decreased with the intensity of cluster thinning. The accumulation of non-anthocyanin phenolics was similarly affected in the two varieties. Notably, cluster thinning was more effective on enhancing the phenolics content than leaf removal. The combination of middle level of leaf removal and cluster thinning was the most favor to the accumulation of phenolic acids. Furthermore, cluster thinning could also significantly enhance the synthesis of flavanols and stilbenes. Lastly, content and variety of aroma compounds in both grape varieties were also significantly affected by the treatments. The results provided a theoretical basis for a combination of leaf removal and cluster thinning to improve quality of grapes and wines.

Overwintering covered with soil or avoiding burial of wine grapes under cold stress:Chinese wine industry’s past and future,challenges and opportunities

In northwest China,where winter is extremely cold and the grapevine is vulnerable to freezing damage,the application of soil covering has promoted the vigorous development of the local grape and wine industries.However,in recent years,the negative effects of burying soil for cold protection on the environment have gradually emerged.In some viticultural regions,the phenomenon of"summer forest,winter desert"has appeared.Therefore,it is urgent for the Chinese grape industry to find a better solution to overwinter safely and environmentally friendly.This review summarizes the advantages and disadvantages of widely used solutions to overwinter such as covering vines with soil,breeding of cold-resistant grapes,cold-resistant cultivation model,physical and chemical covering materials,and protected grape facilities were reviewed.Future overwintering measures were proposed which avoid burial and grape overwintering research directions.It also provides a theoretical foundation and technical support to improve grape yield and quality in northwest China.

Foliar application of chelated sugar alcohol calcium fertilizer for regulating the growth and quality of wine grapes

The eastern foothills of Helan Mountain are a production area of high-quality wine grapes,but the low content of water-soluble calcium in the alkaline soil in this area has become an important limiting factor for the production of high-end wines.In this study,7-year-old Cabernet Sauvignon grapes grown at Lilan Winery,which is located at the eastern foot of Helan Mountain in Ningxia,China,were used to examine the effect of exogenous calcium supplementation on fruit growth and berry quality.Calcium sugar alcohol was applied as a foliar spray at 1.2 L/hm^(2)(T1),2.4 L/hm^(2)(T2),3.6 L/hm^(2)(T3),4.8 L/hm^(2)(T4),and 6.0 L/hm^(2)(T5)concentrations at the fruit expansion stage,the early stage of grape veraison,the middle stage of grape veraison,and the later stage of grape veraison.Water control was used for comparison.The results showed that foliar calcium supplementation can significantly enhance the photosynthetic characteristics of wine grape leaves,increase the chlorophyll content of leaves,and improve the quality of grape berries.Under the T3(3.6 L/hm^(2))concentration of exogenous calcium,the transverse diameter,the longitudinal diameter,and fruit shape index of grapes were the highest,which were increased by 1.71%,5.33%,and 3.92%compared to the control,respectively.The application of high calcium concentrations(T4 and T5)inhibited the physiological development of grapes.The spike length,hundred-grain weight,yield of wine grapes,sugar-acid ratio,tannin,and total phenols were the highest in the T2(2.4 L/hm^(2))treatment.The results of principal component analysis based on multiple indicators showed that foliar application of 2.4-3.6 L/hm^(2)chelated sugar alcohol calcium on the leaf surfaces of grape leaves was the most suitable for improving the physiological characteristics and berry quality of wine grapes.

Nutritional requirements and precise fertilization of wine grapes in the eastern foothills of Helan Mountain

Cabernet Sauvignon grapes in the wine-producing area of Helan Mountain,East Ningxia,China,were the research object in this study.The dissection of the roots and branching stems method was used to explore the dynamic changes in the nitrogen,phosphorus,and potassium nutrient requirements of wine grapes over a number of growth stages.The results showed that over the whole growth period,the nitrogen content of the roots was the highest during the leaf-expansion stage and lowest during the turning-color stage,and that the nitrogen content of the leaves and fruit showed a downward trend as growth progressed.The nitrogen content of the secondary branches was the lowest during the fruit expansion stage and the highest during the leaf-expansion stage;and the phosphorus content of the roots was the highest during the leaf-expansion stage and lowest during the fruit expansion stage.The phosphorus content of the trunk and primary branches showed a trend of“rising-falling-rising”.The phosphorus content of the leaves and secondary branches was the lowest during the turning-color stage,whereas the phosphorus content of the fruit was at its highest during this stage.The potassium contents of the secondary branches and fruit showed a downward trend,but the potassium content of the leaves was highest during the fruit expansion stage and lowest in the nutrient return stage.Over the whole growth period,the accumulation of nitrogen,phosphorus,and potassium in wine grapes was 129.92 kg/hm2,41.51 kg/hm2,and 189.47 kg/hm2,respectively,the total requirements for N,P2O5,and K2O were 262.38 kg/hm2,288.15 kg/hm2,and 569.04 kg/hm2,respectively,and the reasonable nutrient requirement ratio was 1.00:1.10:2.17.

t-SNE:A study on reducing the dimensionality of hyperspectral data for the regression problem of estimating oenological parameters

In recent years there is a growing importance in using machine learning techniques to improve procedures in precision agriculture:in this work we perform a study on models capable of predicting oenological parameters from hyperspectral images of wine grape berries,a specially relevant topic to boost production tasks for winemakers.Specifically,we explore the capabilities of a novel technique mostly used for visualization,t-Distributed Stochastic Neighbor Embedding(t-SNE),for reducing the dimensionality of the highly complex hyperspectral data and compare its performance with Principal Component Analysis(PCA)method,which despite the introduction of many nonlinear dimensionality reduction techniques over the years,had achieved the best results for real-world data across several studies in literature.Additionally we explore the potential of Kernel t-SNE,an extension to the t-SNE method that allows for the usage of the technique in streaming data or online scenarios.Our results show that,in a direct comparison,t-SNE achieves better metrics than PCA for most of the data sets in this work and that the regressor(Support Vector Regression,SVR)performs better with the t-SNE reduced features as inputs,accomplishing better predictions with lower error rates.Comparing the results with current literature,our shallow learning model paired with t-SNE achieves either better or on par results than those reported,even competing with more advanced models that use deep learning techniques,which should propel the introduction of t-SNE in more studies that require dimensionality reduction.

Effects of micro-oxygenation on the aroma of Cabernet Sauvignon wine from Ningxia,China

Micro-oxygenation (MOX) is an effective post-harvest technique for the flavor improvement of grape wine. This study investigated the effect of MOX on the aroma quality of Ningxia wine for the first time. Three sub-region Cabernet Sauvignon dry red wines were treated with different levels of oxygen before or after malolactic fermentation. The wine aroma was analyzed through gas chromatography-mass spectrometry (GC-MS) and quantitative descriptive analysis (QDA) after six months of aging. The data obtained demonstrated that the dose and timing of oxygen addition were key factors influencing the effectiveness of MOX. The most noticeable modifications in wine aroma compounds were generated by an oxygen dosage of 30 (mL/L)/month added before malolactic fermentation. Predominantly, the concentrations of 2-phenylethanol, benzaldehyde, diacetyl, and 2,3-pentanedione showed an increased pattern upon MOX treatments. The sensory analysis revealed that MOX improved the aroma quality of wine by decreasing green and animal odors, meanwhile enhancing the olfactory intensities of dried fruits, flowers, and nuts. This work confirmed that MOX was suitable for aroma modification of Cabernet Sauvignon dry red wine from Ningxia and established a preliminary MOX procedure that can serve as a reference for future applications.