• Food Science and Preservation
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• v.17 no.2
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• pp.174-181
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• 2010

The yeast strains used for fermentation are known to influence the qualities of wine. We investigated the effects of fermentation using different yeast strains on the properties of wine produced from 'Hayward' kiwifruit (Actinidia deliciosa). The physicochemical characteristics of wine produced using various yeast strains for fermentation were also analyzed. Saccharomyces cerevisiae Gervin No.5 strain (GVN), S. bayanus Lavin strain EC1118 (EC1118), and S. cerevisiae Red star Davis No. 796 (No.796) are commercial dry yeast strains selected for optimization of fermentation. Although the soluble solid contents of samples fermented by all three yeast strains decreased by a similar extent, the levels of alcohol production differed, particularly during the first week of fermentation. Use of the GVN strain resulted in the highest alcohol concentration (13.8%, v/v), whereas fermentation with No.796 and EC1118 strains yielded alcohol contents of 13.0% and 12.5% (both v/v), respectively. Upon sensory evaluation, GVN-fermented wine had a strong taste and bitterness, with high acid and alcohol contents. Wine fermented using No.796 had a chemical profile similar to that of GVN-fermented product, but the taste remained sweet, consistent with the lower alcohol content. EC1118-fermented wine was soft and sweet in taste, high in flavor, and had a low alcohol content. Total phenolic levels and antioxidant activities in wine fermented by EC1118 were significantly higher than in wines prepared using No.796 or GVN. When previously described characteristics were additionally considered, EC1118 was selected as an optimum strain for further study. In conclusion, fermentation of kiwifruit using different yeast strains yielded wines with distinct characteristics. The yeast strain EC1118 had the most desirable properties, and is considered suitable for kiwifruit fermentation. Valuable attributes of wine fermented by this yeast include overall sensory acceptance, an appropriate level of total phenolics, and good antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.83-88
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• 2009

After storing green tea powder for three months at three different temperatures (-20, 4, and $20^{\circ}C$) with three different relative humidities (RHs) (23, 69, and 81%), the chemical quality was evaluated with green tea, which was prepared by soaking 1.5 g of the powder into 100 mL of distilled water at $70^{\circ}C$ for 5 min. Total phenolic contents, total flavanol contents, and ascorbic acid contents of green tea powder stored at $4^{\circ}C$ with 23% RH changed from 267.5, 49.4, and 24.2 mg/g to 287.1, 44.9, and 36.9 mg/g, respectively, compared to the powder before storage. EGC and EGCG, the main catechins of green tea, also changed from 16.9 and 27.3 mg/g to 24.3 and 36.5, g/g, respectively, after storage for 3 months at $4^{\circ}C$ with 23% RH. However, when the green tea powder was stored at -20 or $20^{\cric}C$ with higher RH such as 69 and 81%, the chemical compounds were significantly decreased. The results indicate that temperature and RH are important during storage of green tea powder, and low RH and refrigerated condition ($-4^{\cric}C$) are preferable to increase or preserve the chemical compounds of the tea.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.208-213
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• 2012

This study was performed to compare antioxidant activities of 80% EtOH extracts from young and mature fruit of three pear cultivars ('Wonhwang', 'Whangkeumbae', and 'Chuwhangbae') classified by three parts (peel, core, and flesh) of mature fruit. The total phenolics compound and flavonoid contents of 80% EtOH extracts from young fruit were 1.5-2.5 times higher than the mature fruit with great cultivar difference. In particular, the contents of those compounds were highest in 'Chuwhangbae' pear. The total phenolics compound and flavonoid contents of 80% EtOH extracts from mature fruit were the most in the peel, core, and flesh respectively. DPPH radical scavenging and $ABTS^+$ radical scavenging of 80% EtOH extracts from the young fruit were higher than the mature fruit of 'Chuwhangbae' pear. DPPH radical scavenging and ABTS+ radical scavenging of 80% EtOH extracts from mature fruit were the highest in the peel, core, and flesh respectively.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.149-159
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• 2018

The change of quality and physicochemical characteristics of mung-bean flours after germination and roasting treatment were evaluated. The moisture content of the roasted mung-bean flours decreased significantly according to the roasting temperatures and times, and the crude ash, protein and fat contents increased. The lightness of the roasted mung-bean flours significantly decreased, and the redness and yellowness increased. The water binding capacity of the roasted mung-bean flours without and with germination were 151.71 and 192.77% at $240^{\circ}C$ for 20 min, respectively. The water solubility index and swelling power decreased with an increase in roasting temperatures and times. The phenolic compounds and radical scavenging activity of the roasted mung-bean flours increased with an increase in the roasting temperatures and times. The total polyphenol contents of the roasted mung-bean flours without and with germination were 4.81~7.71 and 4.22~5.63 mg GAE/g, and the total flavonoid contents were 2.46~3.05 and 2.45~2.87 mg CE/g, respectively. The DPPH radical scavenging activity of the roasted mung-bean flours, without and with germination, were 106.83~376.08 and 174.41~346.70 mg TE/100 g, and the ABTS radical scavenging activity was 251.67~534.31 and 274.39~430.02 mg TE/100 g, respectively. As a result, it is necessary to set quality standards for each application considering the quality and antioxidant properties of the roasted mung-bean flours.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1308-1315
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• 2017

This study was conducted to develop Momordica charantia L. juice fermented by four Lactobacillus species such as Lactobacillus paracasei (LPA), Lactobacillus plantarum (LPL), Lactobacillus rhamnosus (LRH), and Lactobacillus reuteri (LRE) as well as to investigate their inhibitory effects against digestive enzymes and antioxidant activities. Fermentation was performed at $37^{\circ}C$ without nutrient supplementation for 72 h. The pH and total lactic acid contents were within the ranges of 3.75~3.96 and 5.21~10.04% in fermented juices, respectively. The type of starter culture and fermentation time induced changes in flavonoid contents more than total phenolic contents. All juices fermented for 48 h strongly inhibited ${\alpha}$-glucosidase activity with the percentage of inhibition ranging of 91.24~95.05%. Antioxidant activities of all juices mostly increased after 48 h of fermentation. Our results suggest that fermented juice possesses inhibitory activity against digestive enzymes and antioxidant activity, and they can be used as health functional beverages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1030-1036
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• 2008

In Korea, many types of traditional grape wine have existed starting from seven hundred years ago and horse-blossom-like-grape (mayu-podo) was mainly cultivated. Korean traditional wine (KTW) was manufactured by a unique method in which grape juice-added porridge made from glutinous rice was fermented by nuruk as a starter for brewing. Unfortunately, KTW making was discontinued in 20th century; thus, restoration of Korean wine culture is needed. KTWs were prepared by four traditional methods, and their qualities were compared to commercial wine made by sugaring grape juice. Ethyl alcohol contents, total acidity, pH and amino acid of the four KTWs were $9.2{\sim}11.2%$, $0.93{\sim}1.20\;mg$/100 mL, $3.02{\sim}3.48$ and $0.80{\sim}0.88\;mg$/100 mL respectively. The KTWs showed higher values in total acidity and amino acid than those of commercial grape wine. KTWs were rich in maltose, acetic acid and lactic acid. L, a and b value in Hunter's color value ranged $3.59{\sim}3.69$, $20.63{\sim}38.06$, and $1.20{\sim}1.56$, respectively. Sensory quality properties in color, flavor, taste and overall of KTWs were not different from commercial dry wine. Contents of total phenolic compounds and free radical scavenging activity using DPPH of KTWs were $599.6{\sim}652.2\;mg$/100 mL and $50.59{\sim}56.75%$, respectively.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.763-771
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• 2012

In this study, total antioxidant properties of extracts from different parts of Lespedeza bicolor were determined using techniques of measuring 1,1-diphenyl-2-picryl hydrazyl/2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)-radical scavenging activity and total phenolic contents. The total antioxidant activities of leaf, stem and root extracts from various solvents (water, 50, 70, 100% ethanol, and hot-water) indicated that 50 and 70% ethanol extracts have high radical scavenging activities and phenolic contents. A systematic approach was used to determine the total antioxidant activity of different solvent fractions of the Lespedeza bicolor extracts, partitioning with chloroform, ethyl acetate, n-butanol, and water, and the ethyl acetate fraction was found to have the strongest antioxidant activity. Antioxidant assay-guided isolation was carried out to isolate potential antioxidant compounds. The ethyl acetate fraction of the leaf extract was subjected to silica gel, LH-20 and RP-18 column chromatography successively, and afforded compound 1, which was identified as eriodictyol by NMR and MS analysis, after which its antioxidant activity was determined.

• Food Science and Preservation
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• v.21 no.6
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• pp.917-924
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• 2014

Normal- and late-harvested Fuji apples were fermented using the rapid-fermenting yeast strain Saccharomyces cerevisiae SS89. The late-harvest apples showed a slightly higher soluble-solid content with a lower level of total-acid and moisture (p<0.05) contents as well as hardness (p<0.05) than the normal-harvest apples. During the fermentation, the apples had similar changes in the pH and total-acid content regardless of the harvest time, but the increases in the alcohol content and yeast viable count with the decrease of the soluble-solid content were more rapid in the late-harvest apples than in the normal-harvest apples. After the completion of the fermentation, the soluble-solid and alcohol contents became very similar. The late-harvest cider showed a high total phenolic-compound content and a high DPPH radical scavenging effect, although these were slightly lower than those of the normal-harvest cider. It also showed a higher malic-acid content and higher hue color (p<0.05), Hunter's L, and b (p<0.05) values than the normal-harvest cider. In the sensory evaluation, the late-harvest cider obtained a higher score in taste and a lower score in color compared to the normal-harvest cider.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.175-180
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• 2005

This study was carried out to determine total contents of phenol and flavonoid in common and tartary buckwheat for the purpose of developing new kind of functional food with buckwheat materials. Total content of phenol and flavonoid in seeds of tartary buckwheat were higher than that of common buckwheat. It showed same tendency in groats and hulls. Total content of phenol and flavonoid in groats showed higher than hulls in tartary buckwheat while those of hulls was a little higher than groats in common buckwheat seed. Rutin content in common buckwheat was higher in odor of the hulls (25.2 mg/100 g)>dehulled seed(19.8 mg/100 g)>groats (12.8mg/100 g). But tartary buckwheat was higher in oder of the groats(2042.1 mg/100 g)>dehulled seed (1375.8 mg/100 g)>hulls(138.7 mg/100 g). Flavanol content in dehulled seeds of the tartary and common buckwheat did not show the difference. However, flavanol contents in leaf, stem and spouts of tartary buckwheat were respectively higher than in those of common. Among the flavanols, catechin content was highest in all plant parts of their buckwheat and also was higher in odor of epicatechin>epicatechingallate. However, epicatechingallate content in sprouts of both buckwheat species was about 30-40 times higher than seeds.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.137-147
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• 2014

This study investigates the antioxidant and anti-adipogeneic effects of fermented Rhus verniciflua., evaluating the total phenol, total flavonoids contents and antioxidant activity of the fermented Rhus verniciflua as well as assessing the lipid accumulation during adipogenesis of 3T3-L1 cells. Our results demonstrate that the total phenolic and flavonoids contents of fermented Rhus verniciflua were $29.2{\pm}0.12$ GAE mg/g and $20.4{\pm}1.52$ RE mg/g, respectively. The antioxidative activities of fermented Rhus verniciflua were significantly increased in a dose dependent manner on DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical scavenging, ABTS(2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) radical scavenging, FRAP(ferric reducing antioxidant power)activity, reducing power. In addition, the fermented Rhus verniciflua did not show any cytotoxicity up to 300 ug/mL. However, the anti-adipogenic effect of fermented Rhus verniciflua extract was barely detectable.