• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.316-324
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• 1985

Vacuum-packed and seasoned smoked-dried products of red squid, Ommastrephes bartrami, caught in the Northern Pacific Ocean, were prepared and stored at room temperature for 90 days to test their keeping quality. Defrosted squids were eviscerated, skinned, and cut. The mantle meats were flavored with seasoning powders prepared from sugar, sorbitol, salt, monosodium glutamate, or smoke flavor (Smoke-EZ, Alpha Foods Co., Ltd.). After seasoning, the mantle meats were dried at $45^{\circ}C$ for 7 hours, vacuum packed in plastic film bags, and pasteurized in water at $95^{\circ}C$ for 30 minutes. Three kinds of products were prepared : control products (seasoned-dried), solid smoked seasoned-dried and liquid smoked seasoned-dried. The moisture level, water activity, color value (L, a and b value), texture, and viable cell counts of bacteria in these products were determined during storage at room temperature, $5^{\circ}C\;and\;35^{\circ}C$, respectively. The results showed that the products could be preserved at good condition for 90 days though they developed pale brown color during storage. The contents of free amino acids, nucleotides and their related compounds, and the compositions of fatty acids of raw squid and smoked products were analysed. In the amino acids, arginine, taurine, glycine and proline were abundant in raw and smoked products. The contents of hypoxanthine of raw and smoked products were higher than the other nucleotides and their related compounds. In fatty acid compositions of raw and smoked products, the dominant fatty acids were docosahexaenoic acid (22:6), hexadecanoic acid(16:0) and eicosapentaenoic acid (22:5).

• Food Science and Preservation
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• v.18 no.4
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• pp.559-566
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• 2011

In this study, the good brewing conditions for the 24 $^{\circ}Brix$ freeze-concentrated apple wine were investigated. The four selected Saccharomyces cerevisiae strains MM10, SS89, SS812, and WW108, could ferment quickly when brewed with high sugar levels. During the fermentation, the reducing sugar contents slowly declined while the total acid in all the yeasts increased and the final alcohol content was 12-13%, a typical wine's alcohol content. The viable counts were shown to be 6-6.8 log cfu/ml. During the fermentation, the organic acid content was shown to be within the range of 2.36-3.11%, and the free sugar content, except for the SS89 and WW108 strains, was shown to consist only of sorbitol, although fructose was somewhat detected in the SS89 and WW108 strains. Methanol was not detected, or only a trace of it was detected, and the aldehyde content was 107.68-114.27 ppm. As for the fusel oil contents, a trace of propanol was detected. Isobutanol and butanol were present in 40.16-54.65 and 25.47-27.73 ppm, respectively. The isoamy1 alcohol content was shown to be the highest (108.88-217.26 ppm). The final total phenolic compounds were shown to be 0.1-0.16%. The final Hue values were shown to be 1.3-3.6, and the final intensity was 0.1-0.45. The lightness (L) was within the range of 91.78-98.51, the redness (a) was at a neutral position at red and green, and the yellowness (b) was within the range of 2.38-7.7. In the sensory evaluation, the SS812 strain was found to be the best in terms of color, the SS89 strain in terms of odor, and the WW108 strain in terms of taste. Overall, SS812 was found to be the best apple wine.

• Food Science and Preservation
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• v.14 no.3
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• pp.288-293
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• 2007

Intermediate moisture-apple snail products were prepared by adding glycerol, sorbitol, kiwi, or pineapple(2% or 5% w/w), as tenderizers, and by drying at $4^{\circ}C$ for 24 hr. The effects of the tenderizers on textural and sensory properties of the apple snail products at intermediate moisture levels were investigated. Moisture content and water activity of the products were ranged from 26.25 to 34.48% and from 0.83 to 0.87, respectively. The addition of glycerol significantly lowered water activity of apple snail samples compared to control prepared without tenderizers. On the other hand, significant increases in moisture content and water activity were observed in apple snail samples treated with kiwi or pineapple(p<0.05). All apple snail samples treated with tenderizers showed a lower shear force than did the control. Apple snail samples treated with 5%(v/v) glycerol showed a higher equilibrium moisture content than did the other samples. SDS-PAGE indicated that proteolytic enzymes in kiwi and pineapple clearly changed the structure of the myosin heavy chain and actin filaments of myofibrillar protein in apple snail samples. Intermediate moisture apple snail samples treated with tenderizers showed significantly improved overall sensory characteristics. The highest overall acceptability was obtained from apple snail samples treated with 5% pineapple, while the lowest overall acceptability was noted in the control sample. This study demonstrates that an acceptable apple snail, with intermediate moisture content, may be produced by using tenderizers at appropriate concentrations.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.186-191
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• 2006

In the present study, an attempt has been made to produce hybrid yeast strains of different useful and dominant characteristics. The hybrid yeast strains were produced by electrofusion and their genetic analysis were performed by RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction). The protoplast of Saccharomyces cerevisiae KCTC 7904 and Zygosaccharomyces rouxii KCTC 7966 were obtained above 92% when treated with lyticase at $30^{\circ}C$ for $60{\sim}90$ min after the pretreatment of $1{\sim}2%$ 2-mercaptoethanol at $30^{\circ}C$ for $15{\sim}20$ min. The fusant was produced from paired protoplast stage under the electric pulse at high frequency conditions (1.5 MHz/50 pV, 615 $V/256\;{\mu}sec$) within glass-platinum made electrofusion chamber. Changes in RAPD patterns in mother cells and hybrid cells proved that the fusant contains two types of yeast gene originated from its parent. Furthermore, fermentation characters exhibits by the fusant cell confirmed its genetic changes. These results suggest that genetically stable hybrid yeast strains of economic importance can be produced by electrofusion technique and these electrofused yeast cells have an enormous impact in biotechnology and biomedicine.

• The Journal of the Korean Society for Microbiology
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• v.8 no.1
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• pp.7-11
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• 1973

The authors identified eighty-eight Shigella cultures among about four thousands specimens collected from all over the country in 1972. Of eighty-eight cultures, seventy-seven cultures belonged to Shigella flexneri and eleven cultures to Shigella sonnei. None of cultures belonging to either subgroup A or C was detected in 1972. Of seventy-seven cultures of Shigella flexneri one was $B_{1b}$, fifty-six were $B_{2a}$, nine were $B_{3a}$, six were $B_{4a}$, three were By and one was each of $B_{3b}$ and $B_{3c}$. Of eleven cultures of Shigella sonnei seven cultures appeared to be phase I and the others phase II. Although there was quite a difference found in the incidence of isolating Shigella organisms between different areas as shown in Table 1, it would not be possible to understand that there might not have been the cases or carriers of Shigella in the areas where the organisms were not isolated in 1972. Concerning the biochemical properties it was not possible to compare the results obtained from the decarboxylase and dihydrolase tests with them obtained in previous years except that of lysine decarboxylase tests since they were not reported individually by the different serotypes in the previous reports. These results obtained in 1972 would be the data for the future comparison. In regards to the antibiotics-sensitivity of Shigella cultures the most of them showed sensitive results to nitrofurantoin, ampicillin, cephalosporin, gentamycin and geopen, and the majority of them appeared to be resistant to cloxacillin, tetracycline and streptomycin by means of the In Vitro tests.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.652-660
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• 2002

To develop natural food preservatives for extending the shelf-life of jeotkal (salted and fermented seafood), antimicrobial substances were extracted from 32 types of medicinal herbs and edible plants using 95% ethanol. Among the extracts, Glycyrrhizae radix, Curcumae domestica, Galla rhois, and Resina pini showed relatively high inhibitory effects on the growth of the microorganisms isolated from the deteriorated jeotkal. We selected and tested the extract from Recina pini as a natural jeotkal preservative. This ethanol extract was purified partially by adding equal quantity of water, through which 77% of insoluble materials were removed as impurities. In manufacturing modified jeotkal using squid, sucrose and starch syrup were substituted with sorbitol, $glucono-{\delta}-lactone$ was added instead of vitamin C and lactic acid, and sterilized hot pepper was used instead of natural one. The shelf-life of modified jeotkal was prolonged by 4 days compared with the control jeotkal when stored at $20^{\circ}C$, while that of modified jeotkal containing 1.0% partially purified Recina pini extract was prolonged by 6 days compared to the control. The same tests were conducted for the changran (stomach and intestine of Alaska pollack) jeotkal preservation. The shelf-life of the control jeotkal was 24 days, whereas the modified jeotkal and the Resina pini extract-containing modified jeotkal maintained their qualities without changes in microbial and chemical characteristics for 90 days at $20^{\circ}C$ storage.

• The Journal of the Korean Society for Microbiology
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• v.7 no.1
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• pp.9-15
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• 1972

The authors identified 45 Shigella cultures among 63 suspectable cultures obtained from the cases showing dysentery or the like symptoms in various parts of the country during the period from February to September, 1971. Of 45 cultures, 36 cultures belonged to Subgroup B, 7 cultures to Subgroup C and 2 cultures to Subgroup D. There was none of cultures belonging to Subgroup A in 1971, although the authors detected one culture of that among 41 identified Shigella in 1967. Of 36 cultures belonging to Subgroup B, 27 cultures were $B_{2a}$ and 3 cultures of each $B_{3c},\;B_{4a}$ and $B_y$ were serotyped, respectively. Of 7 cultures beloning to Subgroup C, one was $C_{11}$ and other six cultures were $C_{15}$ and all S. boydii were isolated in Seoul area. It might be possible to suggest that there was a tendency of decreasing prevalence of S. dysenteriae and of increasing prevalence of S. boydii in Korea, although the number of cultures. tested were very much limited to conclude, if it was compared with the results obtained by the authors in 1967 that the fourty-one identified Shigella were composed of one culture of S. dysenteriae, 36 cultures of S. flexneri, 4 cultures of S. sonnei and none of S. boydii. According to the results obtained from the biochemical tests, the positive ratio of Indol tests in Subgroup B was 31/36, which could be higher than 9/36 observed in 1961, but which was nearly correlated with the result published by Ewing and his colleagues in U.S.A. The positive rates of both sorbitol and raffinose were lower than that observed by Ewing and his colleagues in S. flexneri. Regarding with the sensitivity of Shigella cultures to the antibiotics being widely used in the country, 46.2% were sensitive to chloramphenicol, which was very much higher than that observed by Park, and 85.8% were sensitive to ampicillin, which would be the drug of choice according to the results from the In Vitro tests.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1998.10a
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• pp.83-106
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• 1998

This study was conducted to investigate the probiotics(acid and bile resistance, fermentation properties, viability, cholesterol assimilation, antimicrobial activity, antimutagenicity, and immunoactivation) of the strains of bifidobacteria isolated from healthy Koreans and to investigate the effects of oral administration of Bifidobacterium longum A-2 on the fecal microflora, ${\beta}-glucuronidase$ activity, pH values, Ammonia concentration. The experimental results are summarized as follows: The probiotics were tested for 23 strains including three commer챠al strains as controls. Compared to other strains, strains of A-2 and A-9 showed more acid resistance whereas A-2, A-5, A-13, A-14, A-18 and A-22 showed excellent bile resistances. The properties of bifidobacteria during fermentation were tested. Strains of A-1, A-2, A-3, A-4, A-6, and A-23 resulted in less than pH 4.5 and titratable acidity over 0.90 after 24 hr of fermentation. When the strains of A-2 was grown with glucose, maltose, and fructooligosaccharide, the acetic acid production were higher than with sorbitol and mannitol. The storage stability of the strains of A-2 and A-22 were tesed, indicating the strain A-2 was more stable over 10 days of storage at both $4^{\circ}C$ and $20^{\circ}C$ than A-22. The strains of A-8, A-10, A-11, A-12 and A-20 assimilated more than 30% of cholesterol included in the media. The strains of A-1 and A-2 showed antimicrobial activity against Sta. aureus. The antimutagenicity of the strains were also tested, showing that the mutation was suppressed more by three strains(A-2, A-12, and A-23). In addition, strain A-5 improved immunological activity(phagocytosis, $TNF-{\alpha}$, IL-6) more than other strains. In the effects of oral administration of Bif. longum A-2, the number of fecal bifidobacteria was siginificantly increased(p<0.01) and the level of fecal ${\beta}-glucuronidase$ also was siginificantly reduced(p<0.05). However there were no siginificant differences in the level of Lαctobacilli, Enterobacteriaceae, Clostridium perfringens, pH and ammonia by the administration. The results suggested that Bif. longum A-2 may be met the criteria for probiotics culture.