• Journal of Life Science
• /
• v.21 no.2
• /
• pp.292-299
• /
• 2011

This study compared volatile flavor profiles of 4 commercial vinegar beverages (Italian vinegar beverage (IVB), Japanese vinegar beverage (JVB), Japanese Yuzu-Ponz (JYP), and Korean white wine vinegar beverage (KWVB)). Flavor components of vinegar beverages (VBs) were determined using SPME/GC/MSD. The profiles of VBs were as follows; IVB (11 acids, 17 esters, 10 alcohols, 8 aldehydes, 3 terpenes, 4 aromatic hydrocarbons, 9 ketones), JVB (7 acids, 8 esters, 9 alcohols, 7 aldehydes, 13 terpenes, 7 aromatic hydrocarbons, 1 ketones, 3 miscellaneous compounds), JYP (3 acids, 12 esters, 8 alcohols, 7 aldehydes, 63 terpenes, 6 aromatic hydrocarbons, 2 ketones, 5 miscellaneous compounds), KWVB (10 acids, 10 esters, 9 alcohols, 8 aldehydes, 2 terpenes, 5 aromatic hydrocarbons, 4 ketones, 2 miscellaneous compounds). IVB and JVB showed similar flavor compositions (acids, ketones and esters in particular), whereas major components in JYP and KWVB were terpenes (79.6%) and acids (81.0%), respectively. Five compounds including 2-phenylethyl acetate (floral, fruity, sweet odor), 2-phenylethanol (floral, rose odor), vitispirane (fruity odor), geranylacetone (fragrant odor) and acetic acid were identified as major components in balsamic vinegar beverages.

• Microbiology and Biotechnology Letters
• /
• v.25 no.4
• /
• pp.386-390
• /
• 1997

The characteristics of alcohol dehydrogenase (ADH, EC 1.1.1.1, alcohol:NAD oxidoreductase) of thermotolerant alcohol-producing yeasts, Saccharomyces cerevisiae RA-74-2 and Kluyveromyces marxianus RA-912, were compared with that of mesophilic S. cerevisiae D, an industrial strain. Under anaerobic culture condition, both S. cerevisiae RA-74-2 and D had similar level of ADH activity at 30$\circ$C, and the activity of S. cerevisiae RA-74-2 at 37$\circ$C was the same level at 30$\circ$C. However, the level of ADH activity of S. cerevisiae D at 37$\circ$C decreased about 70% of that at 30$\circ$C. The level of enzyme activity of K. marxianus RA-912, which showed lower alcohol productivity than S. cerevisiae RA-74-2 and D, was about 43% of those strains at 30$\circ$C, and decreased somewhat at 37$\circ$C. The results showed a good correlation between the alcohol productivities and the level of ADH activities of these strains grown at 30$\circ$C and 37$\circ$C. And the higher heat stability of ADH of S. cerevisiae RA-74-2 than that of S. cerevisiae D seemed to reflect the ability of high temperature fermentation. Despite of its fermentation ability even at 45$\circ$C, however, the ADH of K. marxianus RA-912 showed lower heat stability than that of S. cerevisiae D. Both S. cerevisiae RA-74-2 and D showed similar patterns of two bands of ADH isozyme, and the low band of S. cerevisiae RA-74-2 moved slightly faster than that of S. cerevisiae D. The staining intensity of the bands of S. cerevisiae D at 37$\circ$C was weaker than those at 30$\circ$C. However, S. cerevisiae RA-74-2 showed no differences in total intensity of the bands of 30$\circ$C and 37$\circ$C. As the patterns of cellular proteins and ADH isozyme of K. marxianus RA-912 were different from S. cerevisiae RA-74-2 and D, K. marxianus might have its own characteristic ADH system.

• Applied Biological Chemistry
• /
• v.15 no.3
• /
• pp.213-219
• /
• 1972

In order to utilize sweet potatoes for the material of Takju, brewing experiments with raw sweet potatoes, sweet potato chips powder and its koji were conducted; and various tests were carried out on effect of the treatments of acid, alkali, polyphenol oxidase inhibitor, oxidizing and reducing agents upon the prevention against coloring of sweet potato chips by steaming, and on peeling effect of sweet potatoes by the alkali and heat treatments. The results obtained were as follows. 1) In the case of brewing with raw sweet potatose, each plot showed low acid and ethanol content, and its finished Takju had an undersirable color and odor. The plots which were mashed after peeling showed higher ethanol contents than the plots mashed without peeling. 2) In the case of brewing with sweet potato chips powder, each plot contained considerably more amount of ethanol than the plots brewed with raw sweet potatoes, white it contained less amount of acid. The ethanol contents of the plots using wheat bran koji were $10.5{\sim}11.4$ per cent 4 days after mashing, and were higher than those of the plots using malts powder. Their finished Takju was inferior in quality because of the lack of acid and being darkened gradually in process of time. 3) The kojies which were made of sweet potato chips powder with Neurospora sitophila or Aspergillus oryzae had good appearance, but the Takju mashes brewed with these contained remarkably less amount of ethanol. 4) Effect of the treatments of acid, alkali, polyphenol oxidase inhibitor and organic solvents such as ether and ethanol upon the prevention against coloring of sweet potato chips was not recognized. Alum and burnt alum were effective a little on the decolorization, and among the oxidizing and reducing agents tested, potassium permanganate was most effective. 5) Darkening of sweet potato chips powder in course of heating after mixing with water was not affected by pectin and amino acids, but by tannin. 6) Sweet potatoes were not peeled easily by friction after soaking in the boiling solution of 3 per cent alkali for 6 minutes and peeled in boiling water for 12 minutes. From the viewpoint of the results above mentioned, it seems to be necessary to study further on the isolation of microorganisms which are able to decompose the coloring substances and yeasts which are adequate for the fermentation of sweet potatoes in order to utilize sweet potatoes for Takju brewing, because brewing with raw sweet potatoes, sweet potato chips powder and its koji was unsuccessful, and effect of the various treatments on the decolorization of sweet potatoes was not recognized.

• Applied Biological Chemistry
• /
• v.32 no.4
• /
• pp.408-415
• /
• 1989

Twenty-seven strains of starch utilizing yeasts were isolated from 30 samples of ‘Nuruk’, a traditional starter in Korea. These strains were identified as ten species belonging to four genera; Hansenula anomaly (six strains), Hansenula sydowiorum (two strains), Saccharomycopsis fibuligera (four strains), Schwanniomyces occidentalis (two strains), Candida fabianii(two strains), Candida famata(one strain), Candida hydrocarbofumarica (three strains), Candida silvicola (one strain), Candida steatolytica (four strains) and Candida tropicalis (two strains). Saccharomycopsis fibuligera Nu-01, Nu-08, Nu-12 and Nu-27 produced much amylase, and one of these, Saccharomycopsis fibuligera Nu-12 showed the highest amylase activity (16.9 IU/ml). Among the isolates, the strains of Hansenula anomala were exhibited relatively high specific growth rate in the medium used starch as a carbon source, and ethanol fermentation by the strains of Candida hydrocarbofumarica was not observed.

• Korean Journal of Food Science and Technology
• /
• v.18 no.5
• /
• pp.398-405
• /
• 1986

The food quality of lupin seed, i.e. soaking, cooking, sprout growing and mold growing for fermentation, was investigated by using the seed of Lupinus angustifolius harvested in Western Australia. A method to produce lupin seed protein concentrate (LPC) was developed, and the wage of LPC in Korean food system was investigated. The water soaking rate of lupin seed was faster than that of soybean, but the cooking rate of lupin seed was much slower compared to soybean. The thermal softening time, $D_{100}$, was 345 min for lupin seed and 84 min for soybean. A two-phase solvent extraction system consisting of haxane-alcohol-water could effectively remove the residual bitter taste, lipid and yellow pigments of lupin seed flour, and the resulting LPC contained over 50% protein and had bland flavor and milky white color. Treatment of LPC with carbohydrate decomposing enzymes resulted in a product of more soluble and higher concentration of protein. Methods to produce lupin seed vegetable milk and lactic beverages from LPC products were discussed.

• Korean Journal of Microbiology
• /
• v.27 no.3
• /
• pp.216-220
• /
• 1989

As the bsic study about protoplast fusion of amylolytic fungus Aspergillus oryze and nonamyloytic sugar fermenter, Saccaromyces cerevsisae, the intraspecific protoplast fusion of A. oryzae was carried out and the properties of the obtained fusants were investigated. For protoplast fomation from mycellia of auxotrophs, Novozyme 234 as lytic enzyme was the most effective and optimal pH was determined to be pH 5.5-6.0. When the two types of protoplasts were treated with a fusogen including 30% PEG4000, they fused effectively and most of fusants were heterokaryons. Protoplasts aggregated with 30% PEG4000 after fusion treatment were observed by the microscope. Protoplast regeneration frequency was 1.46 to 13.8% and complementation frequency of fusion was 0.12 to 0.16. Fusant strains had a 1.5-fold DNA content compared to that of parent strain. And amylase activity was intermediate between those of parent strains.

• Food Science and Preservation
• /
• v.7 no.2
• /
• pp.233-239
• /
• 2000

To proceed mass production and improve its quality, we fermented potatoes using pilot system and investigated the changes in components during fermentation. After liquefaction and saccharification of potatoes by Nuruk(group I), crude enzyme(group II) and glucoamylase(group III), sugar contents in all groups were 18brix equally. However sugar contents in group(II) and group(III) after 24hrs decreased deeply to 7.2 and 8.8 % respectively, after 24hrs. Alcohol content in group(I) increased slowly and was the highest such as 6.8% after 48hrs. Fusel oils in all groups were n-propanol, isobutanol and isoamylalcohol. The major fusel oil in all groups was isoamylalcohol. At the early stage of fermentation, free sugars were glucose, maltose and lactose. Glucose decreased deeply during fermentation and at latter of the fermentation, galactose was detected in all groups. The contents of total free amino acid were 516.57~569.98 mg% in group(I), 193.97~292.11 mg% in group (II) and 186.31~270.53 mg% in group(III). The contents of aspartic acid, serine, glutamic acid, alanine, arginine, and histidine were high in all groups.

• Journal of Environmental Science International
• /
• v.6 no.1
• /
• pp.61-67
• /
• 1997

Heavy metal adsorption by microbial cells is an alternative to conventional methods of heavy metal removal and recovery from metal-bearing wastewater The waste Sac-chuomyces cerevisiae is an inexpensive, relatively available source of biomass for heavy metal biosorption. Biosorption was investigated by free and immobilized-S. cerevisiae. The order of biosorption capacity was Pb>Cu>Cd with batch system. The biosorption parameters had been determined for Pb with free , cells according to the Freundlich and Langmuir model. It was found that the data fitted reasonably well to the Freundlich model. The selective uptake of immobilized-S. cerevisiae was observed when all the metal ions were dissolved in a mixed metals solution(Pb, Cu, Cr and Cd). The biosorption of mixed metals solution by immobilized-cell was studied in packed bed reactor. The Pb uptake was Investigated in particular, as it represents one of the most widely distributed heavy metals in water. We also tested the desorption of Pb from immobilized-cell by us- ing HCI, $H_2SO_4$ and EDTA.

• The Korea Journal of Herbology
• /
• v.24 no.1
• /
• pp.133-139
• /
• 2009

Objectives : This study was designed to investigate the effects of alcoholic fermentation extract from ovary and rind of pear on human skin. Methods : We investigated the effects of samples on human skin in terms of clinical trial. 32 of healthy volunteers, who lived in mokpo participated in clinical trial. Effects of sample on hygroscopicity and water-holding capacity were investigated. Sebum, moisture, scabrousness and desquamation were also investigated. Facial massages were conducted 8 times in each volunteers. Results : Single treatment group showed elevated levels of hygroscopicity (Normal : 106.4$\pm$2.1%, vs Pear : 114.1$\pm$6.2) and water-holding capacity (Normal : 87.1$\pm$4.4%, vs Pear : 96.2$\pm$1.3) on forearm of 16 volunteers respectively. In addition, massage group using sample showed elevated moisture (Control : 3.8$\pm$5.8%, vs Sample : 15.2$\pm$4.7%) and lowered scabrousness levels (Control : -12.3$\pm$4.4%, vs Sample : -22.0$\pm$5.2%) significantly. However, the levels of sebum did not affected by sample. Conclusions : These result suggest that alcoholic fermentation extract from ovary and rind of pear has moisturizing effect on human skin.

• Korean Journal of Microbiology
• /
• v.30 no.6
• /
• pp.546-552
• /
• 1992

Ethanol-tolerant strain, S. eerevisiae BUI a26 ($alc^r thr^-$) and gJucoamylase-producing strain, S diastatieus AI5a6 (STA+ hom-) were prepared by means of genetic manipulation, Protoplast fusion was carried out to introduce STA gene from AI5a6 strain to BUla26 strain, Protoplast formation was shown at 0,8 M sorbitol and 200 Jig/ml to 400 Jig/ml zymolyase treatment for 2 hours incubation, Fusion frequency was $ 3.25 {\times} 10^{-3}$ to the regenerated protoplast number using PEG 6000 for 90 min incubation. The excellent fusants with genotype of STA- $alc^r thr^-$ hom+/STA+ ($alc^s thr^+$ hom- (2n), F7 and FIO, were selected by ethanol-tolerant, ethanol fermentation, and glucoamylase production tests, Glucoamylase production of AI5a6 showed 2,7 units, but 4.2 or 8.4 units for F7 or FIO fusant at $30^{\circ}C$, Ethanol fermentation from 32% glucose by BUla26 was 14,0%(v/v) in fermentaion medium for 5 days incubation, but 14.5% or 15,0% for F7 or FIO strain, respectively. Ethanol fermentation from 5% starch was 2,0% by F7, or 1.8% by FIO strain in fermentation medium for 5 days fermentation.