Flavor Chemical Profiles of Cabernet Sauvignon Wines: Six Vintages from 2013 to 2018 from the Eastern Foothills of the Ningxia Helan Mountains in China

The eastern foothills of the Helan Mountains in the Ningxia region (Ningxia), is a Chinese wine-producing region, where Cabernet Sauvignon is the main grape cultivar; however, little compositional or flavor information has been reported on Ningxia wines. Oenological parameters, volatile profiles, and phenolic profiles were determined for 98 Ningxia Cabernet Sauvignon wines from the 2013–2018 vintages, as well as 16 from Bordeaux and California, for comparison. Ningxia wines were characterized by high ethanol, low acidity, and high anthocyanin contents. Multivariate analysis revealed that citronellol and 12 characteristic phenolic compounds distinguish Ningxia wines from Bordeaux and California wines. The concentrations of most phenolic compounds were highest in the 2018 Ningxia vintage and decreased with the age of the vintage. To our knowledge, this is the first extensive regionality study on red wines from the Ningxia region.

Phenolic Composition and Antioxidant Activity of Peel, Pulp and Seed Extracts of Different Clones of the Turkish Grape Cultivar ‘Karaerik’

The Erzincan plain is one of the richest regions in Turkey in terms of plant biodiversity. In this region, the famous grape cultivar ‘Karaerik’ has always dominated grape production due to its berry characteristics. The cultivar shows great morphological variation at clonal level. In this study, the total phenolic content and antioxidant activity of peel, pulp and seed extracts of nine ‘Karaerik’ clones sampled from same location were investigated. The Folin–Ciocalteu method was used to determine the total phenolic content of peel, pulp and seed extracts of nine clones. To determine antioxidant activity, three well known assays such as DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate), FRAP (Ferric Reducing Antioxidant Power) and TEAC (Trolox Equivalent Antioxidant Capacity) were used. In addition, the correlation between total phenol content and DPPH, FRAP and TEAC was determined. Results showed that among the tissues, seed samples in berries of all clones had the highest total phenol content and antioxidant activity determined by three assays. Seed samples were followed by peel and pulp for total phenolic content and antioxidant activity. Among the nine ‘Karaerik’ clones, Clone 8 had the highest total phenolic content (149 mg GAE/100 g FW) while Clone 3 had the lowest (111 mg GAE/100 g FW). Peel, pulp and seed samples of nine ‘Karaerik’ clones showed strong antioxidant activity in DPPH, FRAP and TEAC assays. In particular, grape seeds were found rich for better in phenolic compounds including gallic acid, quercetin, catechin, chlorogenic acid, caffeic acid and p-coumaric acid. Clones such as 7, 8 and 9 higher antioxidant activity may present great potential for grape breeders and the food industry as well as health-conscious consumers.

Influence of wine components on pellicle formation by pellicle-forming yeasts

This study aimed to clarify differences in susceptibility to red wine pellicle formation by pellicle-forming yeasts between two wine grape cultivars and to investigate wine components affecting pellicle formation. Twenty wines each of Muscat Bailey A (MBA) and Merlot (MR), the major grape cultivars of Japanese red wine, were used. Pellicle formation occurred more often in MBA wines than in MR wines, and almost all MBA wine surfaces were covered with pellicle after incubation for five days. Principal component analysis revealed the relationships between pellicle formation and the concentrations of ethanol, phenolics and tannins. The mean concentration of tannins in the pellicle MR wines (436 mg/L) was significantly lower than that in the non-pellicle MR wines (660 mg/L). Furthermore, the mean concentration of tannins in MBA wines (139 mg/L) was also significantly lower than that in MR wines (570 mg/L). Wine grape cultivar having a low concentration of tannins may be highly susceptible to pellicle formation by pellicle-forming yeasts during winemaking.

Sustainable Viticulture on Traditional ‘Baran’ Training System in Eastern Turkey

Erzincan plain is one of the most fascinating regions in Turkey for plant biodiversity. The area is very rich in terms of gene, species and ecosystem diversity. Having a number of natural habitats, mountains, etc., the region is one of the richest regions in Turkey for plant endemism as well. In northern parts of the region, in particular in Üzümlü, Bayırbağ and Pişkidağ districts, grape production dominates agriculture production and the famous ‘Karaerik’ grape cultivar has been cultivated for a long time on the very special traditional ‘Baran’ training system to avoid cold damage that occurs in winter months. The cultivar is harvested between 1 September and 1 October according to altitude in the region. The cultivar is well known in Turkey and there is a great demand for this cultivar in Turkey due to its perfect berry characteristics. In this study, yield, marketable product, cluster weight, cluster form, organic acids, specific sugars and sensory characteristics of the ‘Karaerik’ grape cultivar grown in three altitudes (1200 m a.s.l., 1400 m a.s.l. and 1600 m a.s.l., respectively) in Üzümlü district were investigated. For each altitude, grape clusters were sampled from ten vineyards and an average sample was formed. Marketable product, cluster weight, cluster form, organic acids and specific sugars were determined on those samples. Yield was determined as per decare. Sensory characteristics of samples were determined by five expert panelists. Results showed that the cluster weight was the highest in lower altitude and increasing altitude formed a more conical cluster form compared to winged cylindrical clusters at lower altitudes. The highest yield (740 kg per decare) was obtained in 1200 m a.s.l. and was followed by 1400 m a.s.l. (682 kg per decare) and 1600 m a.s.l. (724 kg per decare), respectively. Altitude strongly affected sugar and organic acid composition and ratio in berries of the ‘Karaerik’ grape. Fructose and tartaric acid were the main sugar and organic acid at all altitudes and were found between 10.04–14.02 g/100 g and 2.17–3.66 g/100 g, respectively. Sensory scores were also the highest at lower altitudes and decreased parallel to altitude increase.

THE EFFECTS OF PARAFFIN AND PARAFILM APPLICATIONS AND DIFFERENT ROOTSTOCKS ON YIELD OF GRAFTED VINE IN ‘BLACK MAGIC’ GRAPE CULTIVAR

The scions belonging to 'Black Magic' grape cultivar were grafted on ‘41B’, ‘1103 P’, ‘Fercal’ and ‘SO4’ American rootstock cuttings using omega grafting method in the experiment. Paraffin was applied to one half of the grafted cuttings. The other half was wrapped with parafilm and then paraffin was applied. Grafted cuttings were planted in perlite medium at 3.0 x 3.5 cm intervals inside plastic buckets and kept in the stratification room for 4 weeks. Grafted cuttings, which had been maintained under room conditions for one week, were then grown for two months under unheated greenhouse conditions. In order to determine rootstock and application effects, bud burst ratio (%), callus formation rate (%), callus formation degree (0-4), rooting ratio (%), rooting degree (0-4), shoot length (cm), shoot diameter (mm) and grafted vine ratio (%) were examined. According to the results of the study, it was determined that paraffin+parafilm application yielded better results than paraffin application in terms of bud burst ratio (respectively 70.83%, 53.33%), callus formation ratio (respectively 83.75%, 69.58%) and yield of grafted-vines (respectively 68.33%, 51.67%). In terms of the rootstocks, bud burst ratio was determined to be the highest in SO4 rootstock (71.67%) and the lowest in Fercal (54.17%). 1103 P rootstock yielded a highest value than other rootstocks in terms of shoot length (26.17 cm), callus rate at grafting surface (88.33%), and rooting ratio (97.50%). The effect of rootstocks on shoot diameter, rooting degree, and grafted vine ratio was found to be similar.

Aroma and Sensory Profiles of Sauvignon Blanc Wines from Commercially Produced Free Run and Pressed Juices

Sauvignon blanc is the most important grape cultivar within the New Zealand wine industry, and wines from the Marlborough region are renowned for their intense aromas including tropical, passionfruit, and green capsicum. Quality Sauvignon blanc wines are usually made from free run juice, although press fractions can be included. The chemical aroma composition and sensory profiles of two wine sets made from three press fractions (free run, light press and heavy press) were compared. The compounds 3-mercaptohexan-1-ol and 3-mercaptohexyl acetate were found to decrease between free run and heavily pressed wines while hexyl acetate, hexanol, and benzyl alcohol increased. The accompanying sensory analysis showed that free run wines were marked by aromas of Passionfruit/sweaty, Boxwood and Fresh green capsicum, while the heavy pressed wines were described by French vanilla/bourbon, Floral and Banana lolly attributes, consistent with the aroma chemical composition.

Projected Wine Grape Cultivar Shifts Due to Climate Change in New Zealand

Climate change has already been affecting the regional suitability of grapevines with significant advances in phenology being observed globally in the last few decades. This has significant implications for New Zealand, where the wine industry represents a major share of the horticultural industry revenue. We modeled key crop phenological stages to better understand temporal and spatial shifts in three important regions of New Zealand (Marlborough, Hawke's Bay, Central Otago) for three dominant cultivars (Merlot, Pinot noir, and Sauvignon blanc) and one potential new and later ripening cultivar (Grenache). Simulations show an overall advance in flowering, véraison, and sugar ripeness by mid-century with more pronounced advance by the end of the century. Results show the magnitude of changes depends on the combination of greenhouse gas emission pathway, grape cultivar, and region. By mid-century, in the Marlborough region for instance, the four cultivars would flower 3 to 7 days earlier and reach sugar ripeness 7 to 15 days earlier depending on the greenhouse gas emission pathway. For growers to maintain the same timing of key phenological stages would require shifting planting of cultivars to more Southern parts of the country or implement adaptation strategies. Results also show the compression of time between flowering and véraison for all three dominant cultivars is due to a proportionally greater advance in véraison, particularly for Merlot in the Hawke's Bay and Pinot noir in Central Otago. Cross-regional analysis also raises the likelihood of the different regional cultivars ripening within a smaller window of time, complicating harvesting schedules across the country. However, considering New Zealand primarily accommodates cool climate viticulture cultivars, our results suggest that late ripening cultivars or extended ripening window in cooler regions may be advantageous in the face of climate change. These insights can inform New Zealand winegrowers with climate change adaptation options for their cultivar choices.

Genome-Wide Identification of Sequence Variations and SSR Marker Development in the Munake Grape Cultivar

The Munake grape cultivar produces uniquely flavored and high-quality fruits. Despite the numerous beneficial agronomic traits of Munake, there are few genetic resources available for this cultivar. To address this knowledge gap, the entire genome was sequenced using whole-genome sequencing approaches and compared with a Vitis vinifera L. reference genome. This study describes more than 3 million single nucleotide polymorphism (SNP), 300,000 insertion and deletion (InDel), 14,000 structural variation (SV), and 80,000 simple sequence repeat (SSR) markers (one SSR per 4.23 kb), as well as their primers. Among the SSRs, 44 SSR primer pairs were randomly selected and validated by polymerase chain reaction (PCR), allowing discrimination between the different Munake cultivar genotypes. The genetic data provided allow a deeper understanding of Munake cultivar genomic sequence and contribute to better knowledge of the genetic basis behind its key agronomic traits.