• Horticultural Science & Technology
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• v.34 no.5
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• pp.692-700
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• 2016

The objective of this study was to determine the differences in fruit growth, fruit quality, and particularly the pedicel vascular bundles of 'Shigyoku' and 'Heukboseok' grapes, which appeared to be different in softening at harvest. 'Shigyoku' grape matured faster (by about 20 days) than 'Heukboseok' grape with slight fruit enlargement after veraison. However, fruit of 'Heukboseok' grapes showed remarkable enlargement in both the primary and secondary fruit enlargement periods. Hypodermal cell layers were not different after veraison in 'Shigyoku' grape, but degradation of the hypodermis cell wall continued in 'Heukboseok' grape, resulting in a gradual decline in firmness. The numbers of hypodermal cell layers in 'Shigyoku' and 'Heukboseok' grapes were 14.2 and 9.0, respectively. The average content of soluble solids in 'Shigyoku' grape ($19.5^{\circ}Brix$) was significantly ($p{\leq}0.01$) higher than that of 'Heukboseok' grape ($17.0^{\circ}Brix$). Xylem of the pedicel did not differ between the two varieties. However, average phloem area after veraison of 'Shigyoku' grape ($19044.8{\mu}m^2$) was about 1.8 fold greater than that of 'Heukboseok' grape ($10509.4{\mu}m^2$), based on the number of cells constituting the phloem. The cell number and area of the phloem might affect the accumulation of sugars, the main constituents of the cell wall, thus maintaining the firmness of grapes until late maturity. Therefore, the increased softening of 'Heukboseok' grapes at harvest might due to their phloem structure.

• Food Science and Preservation
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• v.17 no.6
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• pp.807-813
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• 2010

Muscat Bailey A grapes, one of the major grape varieties in Korea, contain 18-20% (w/w) sugars, which is less than the amount required to make red wine. In the present study, fermentation of freeze-concentrated Muscat Bailey A grape juice to $24^{\circ}Brix$ was performed using several industrial wine yeasts, including Saccharomyces cerevisiae $OC_2$, S. cerevisiae Fermivin and S. cerevisiae W-3. During fermentation, changes in the levels of soluble solids, alcohols, and yeast viable counts were monitored. Wine quality parameters including organic acid, minor alcohol, sensory score, etc. were also analyzed. Alcohol contents reached maximal levels after 9 days of fermentation, and were 12.6% (v/v) when Fermivin was used and 13% (v/v) when strains $OC_2$ and W-3 were used. No major difference between strains was apparent, except that Fermivin fermentation was somewhat slower in terms of both alcohol production and sugar consumption. Similar levels of soluble solids and total phenols were measured in wines fermented by each of the three strains. The total acid level of W-3 wine was high, whereas the alcohol content of Fermivin wine was low. Although the wines were variable in terms of acetaldehyde and minor alcohol contents, the levels of these materials were much lower than the limits set by the Korean National Tax Service. Upon sensory evaluation, $OC_2$ wine obtained the highest scores in terms of color, flavor, and overall acceptance. However, the best taste score was awarded to the Fermivin wine, which had the same flavor score as $OC_2$ wine but a slightly lower overall acceptance score.

• Korean Journal of Medicinal Crop Science
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• v.13 no.6
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• pp.234-240
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• 2005

This study was conducted to identify cross compatibility with table grape and pollen characteristics by flower type in Vitis amurensis Rupr. (GW-22, GW-45, GW-56, GW-200, GW-202 and GW-300) collected in Gangwon area. Flower structure, germinability and morphology of pollen, and cross compatibility with table grape were examined. Flowers of GW-22 and GW-56 had an aborted gynoecium and five erect fdaments, and all of them was male. The percentage of pollen germination of GW-22 and GW-56 on the agar medium was 27.6-29.8%. Flowers of GW-45, GW-200, GW-202 and GW-300 had well-developed pistils and five stamens with curled filaments. The percentage of pollen germination of female plant on the agar medium was 0%. Pollen grail)s from GW-22 and GW-56 (male flower) have symmetrically distributed three furrows on their surface and each furrow contains a germ pore at the equatorial level (Tricolporated). GW-45, GW-200, GW202, and GW-300 (Female flower) produced pollen grains with no germinative structures (acolporated). In self-pollina-tion of female flowers, berries of clusters were no berry and no seed. Therefore, flower structure in V. amurensis proved to be that of other dioecious Vitis species. In cross combination of female and male flower of V. amurensis made normal seeds. In cross combination of table grape and V. amurensis of male flower made normal seeds. But, in cross combination of female flower of V. amurensis did not make seeds. Therefore, V. amurensis was cross compatible with vitis spp, and V. amurensis varieties may contribute to breeding studies of Vitis spp.

• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.134-139
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• 1972

The contents and their seasonal changes of non-volatile organic acids and sugars of various fruits in Korea, apricot(maesil), peach, grape, apple and pears were measured. The organic acid contents were determined by gas chromatography and the free sugars were detected by thin layer chromatography. The results were as follows: 1) The common non-volatile organic acids found in those fruits were oxalic, fumaric, succinic, maleic, tartaric and citric acids: though their contents varied from almost none to 3430mg/100g. 2) Malic acid was contained in all above fruits with generally the highest contents ranging $18{\sim}3430mg/100g$ among different fruits. In every fruits oxalic was the least contained among other organic acids, almost none to trace except apricot(maesil) which contained 10.8mg/100g. 3) It seemed that generally all the non-volatile acids contents decreased after ripening except maleic acid and the cases of an apple and a pear varieties where they increased. 4) Glucose and fructose were detected in all fruits both matured and unripened by thin layer chromatography. Maltose was found in apricot(maesil), peach, grape and apple. Sucrose was detected in apricot(maesil), peach, grape, apple and pear.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1516-1516
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• 2001

During the recent years, wine analysis has played an increasing role due the health benefits of phenolic ingredients in red wine [1]. On the other hand there is the need to be able to distinguish between different wine varieties. Consumers want to know if a wine is an adulterated one or if it is based on the pure grape. Producers need to certificate their wines in order to ensure compliance with legal regulations. Up to now, the attempts to investigate the origin of wines were based on high-performance liquid chromatography (HPLC), gas chromatography (GC) and pyrolysis mass spectrometry (PMS) [l,2,3]. These methods need sample pretreatment, long analysis times and therefore lack of high sample throughput. In contradiction to these techniques using near infrared spectroscopy (NIRS), no sample pretreatment is necessary and the analysis time for one sample is only about 10 seconds. Hence, a near infrared spectroscopic method is presented that allows a fast classification of wine varieties in bottled red wines. For this, the spectra of 50 bottles of Cabernet Sauvignon, Lagrein and Sangiovese (Chianti) were recorded without any sample pretreatment over a wavelength range from 1000 to 2500 nm with a resolution of 12 cm$\^$-1/. 10 scans were used for an average spectrum. In order to yield best reproducibility, wines were thermostated at 23$^{\circ}C$ and a optical layer thickness of 3 mm was used. All recorded spectra were partitioned into a calibration and validation set (70% and 30%). Finally, a 3d scatter plot of the different investigated varieties allowed to distinguish between Cabernet Sauvignon, Lagrein and Sangiovese (Chianti). Considering the short analysis times this NRS-method will be an interesting tool for the quality control of wine verification and also for experienced sommeliers.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.420-428
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• 2015

The majority of cultivated varieties of grape have perfect flowers that are clustered in an individual inflorescence. Grape flower has a single pistil, five stamens, a protective flower cap (calyptra), and a calyx. After fertilization, an individual flower develops into a single berry. Although there are a number of reported studies focusing on berry formation, berry enlargement, and sugar accumulation in grape, the morphological studies of flower, including gametophyte morphogenesis and structural change in floral organs, have not yet been studied in detail. In this study, we investigated the flower structure and development characteristics of grape using microscopy and defined the floral development stages 9 to 13 based on microspore or male gametophyte development stage from tetrad to mature pollen. We used seeded diploid table grapes 'Campbell Early' (Vitis labruscana) and 'Tamnara' (V. spp.) as plant materials. At floral development stage 9, pollen mother cells develop to tetrads. During floral development stages 10 to 11, unicellular microspore develop to mid bicellular pollen. At the end of floral stage 12, male gametophyte develops to mature tricelluar pollen. In floral stage 13, the flower cap falls off and flower bud opens. During floral development stages 9 to 12, there were no major changes in calyx length, whereas the length of the flower cap continuously increased. The flower cap-to-calyx length ratio was 2.0, 3.0, 4.5, and 6.5 at floral stages 9, 10, 11, and 12, respectively. The flower cap-to-calyx length ratio was consistent in the two grape cultivars, suggesting that the ratio is a morphological character representing floral development stage. This study provides a reference for determining floral development stage of the two grape cultivars. It will be useful for the determination of optimum time for microspore culture needed to generate doubled haploid lines and appropriate gibberellic acid treatment needed to induce parthenocarpic fruit development in 'Tamnara' grape.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.290-297
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• 1997

Danored is considered as the most favorable grape variety for national wine manufacturing in terms of sugar, organic acid contents, annual production amount, as well as quality control convenience after harvest. This study was canied out to know the influence of suspended solid(SS) and skin contact time(SCT) with Danored variety on the white wine quality. The results are summarized as follows; 1. Suspended solid and skin contact time did not greatly influence on the chemical composition of Danored juice. But skin contact time provided slightly increaseness to the content of phenol compounds 2. Suspended solid accelerated fermentation rate of white wine manufacturing. Although the content of suspended solid are less amount than 0.3% in must, wine fermentation was completed to dryness in concentration of sugar. 3. When the content of suspended solid was around 3%, higher alcohol in white wine was increased by the 20%. This result is relatively small increasement compared to the other reported results. 4. Because Danored contained less amount of phenol compounds comparison with other grape varieties, browning capacity in white wine was much favorable to quite low concentration. Especially, phenolic compounds was decreased remarkably as one of fermentation characteristics of Danored variety. 5. As a result of sensory evaluation, wine quality was A-1> B-1> A-2> B-2 in its favorable ranking orders. It was so concluded that A-1 might be the most acceptable one from this study.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.164-169
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• 2002

Five kinds of red wine from three different grape varieties, such as Gerbong (G), Campbell (C), Moru (M), Gerbong+Moru (70:30, GM), and Gerbong+Campbell(70:30, GC) were prepared in the year of 2000. The total phenolic content and color changes were monitored using hunter colorimeter and spectrophotometry methods during wine processing. The total phenolic content of Gerbong (G), Campbell (C), Moru (M), Gerbong+Moru(70:30, GM), and Gerbong+Campbell(70:30, GC) were 712.6 mg/L, 3472.9 mg/L, 2209.4 mg/L, 2019.4 mg/L, and 1184.5 mg/L, respectively. Between total phenolic content and hunter colorimeter value (L, a, and b) of red wine showed no significant difference, but that of spectrophotometry color value (hue and intensity) were significantly different (p<0.001). The total phenolic content, hue, and intensity values represented significantly different between grape varieties (p<0.01, p<0.001). the hue showed a negative correlation relationship $(r^2=0.8660,\;p<0.0001)$, and that of intensity was a positive $(r^2=0.8304,\;p<0.0001)$ between total phenolic contents. The total phenolic content of red wine could be estimated simply using these equations, $Y_{Total\;phenolic\;content\;(mg/L)}=3319.3-X_{Hue}/2208.36,\;and\;Y_{Total\;phenolic\;content\;(mg/L)}=1230.97-X_{intensity}/98.93$

• Food Science and Preservation
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• v.15 no.1
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• pp.150-154
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• 2008

This study investigated 1he fermentation characteristics and sensory properties of white wine made from the Chilean grape varieties Thomson Seedless (T), Red Globe (R), and a mixture thereof (M). The pH fell during fermentation and final pH values of 3.63-3.68 were slightly higher than is usual in white wine. The total acidity increased during the alcoholic fermentation and leveled at 0.56-0.71% Ater 15d, the sugar contents and specific gravities attained final values. The L value of wine made from R grapes increased from 65.05 to 96.77, of wine made from T grapes from 77.41 to 99.6, and of wine made from M grapes from 71.73 to 98.41. The a value of all wines decreased quickly during the first 4 d of fermentation and the b values of T and M wines (not R wine) also fell rapidly during this time. The final alcohol concentrations of the wines were 14 -14.9% (v/v). The white wines made from T, R, and M grapes received similar scores in a directional difference sensory test. The color and flavor of white wine made from T grapes scored highest (5.6 and 5.35 respectively; p<0.05 for both values), but overall acceptabilities of all three wines were similar (4.30-4.85, p<0.05).

• Food Science and Preservation
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• v.17 no.5
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• pp.616-624
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• 2010

We compared the physicochemical properties of, and volatile components in various commercial fruit vinegars (made from apples, grapes, and persimmons). Total acidity was highest in grape vinegars. Significant between-sample differences were evident in total and reducing sugar contents. Brownness, turbidity, and overall color difference (the ${\Delta}E$ value) were highest in persimmon vinegars. Free sugars were composed mainly of fructose, glucose, sucrose, and maltose. Major organic acids were present in the (descending abundance) order acetic acid, oxalic acid, citric acid, malic acid, and succinic acid, among-samples difference were negligible. Nine-essential free amino acids were detected in nine types of grape and persimmon vinegars, and in six varieties of apple vinegar. Among 17 types of volatile compounds identified in apple vinegars, 12 in grape vinegars, and 33 in persimmon vinegars, the main volatile components were acetic acid, ethyl acetate, isoamyl acetate, isovaleric acid, isoamyl alcohol, propanoic acid and phenethyl acetate. Volatile chemicals in commercial fruit vinegars were effectively analyzed using a SAW e-nose.