• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.812-813
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• 1995

Lactococcal cells are nutritionally fastidious and thus, generally cultured either in milk or M17 medium (Terzaghi and Sandine, 1975). In this study, Lactococcus cremoris wild-type (KH) and its less­proteolytic mutant (KHA1) cells were grown on the M17 medium or with modified M17 medium by replicated parallel experiments. The modified M17 medium had the same composition as M17 medium, except that lactose was replaced by glucose. Analyses of culture-broth samples, in which the M17 and the modified M17 media were used, were conducted by high-performance liquid chromatography (HPLC). But, working with these media created noisy problems in analyses of samples. Therefore, a new semi-synthetic medium was developed on the basis of nutritional requirements (Morishita et al., 1981). The composition of the semi-synthetic medium determined on the basis of the nutritional requirements and the composition of milk, is presented in Table 1. The composition of M17 medium is also presented and compared in the table. L. cremoris KH and KHA1 cells were grown again on the new synthetic medium containing glucose or lactose. The broth samples were then drawn and analyzed by HPLC. Clearer separations of fermented products were achieved from the new medium than those with the M17 and the modified M17 media. In comparison with the M17 or the modified M17 media, growth on the new medium was good (Kim et al, 1993). Additional fermentations were also carried out at a controlled pH of 7.0, where enhanced growth of lactococcal cells was obtained. In the fermentations, samples were also analyzed for the concentrations of sugar and lactic acid. The results showed that the new synthetic medium was as good as or better than the M 17 and the modified M 17 media. This is because casein hydrolysate in the synthetic medium provided a ready supply of amino acids and peptides for L. cremoris KH and KHA1 cells. Lactic acid bacteria (LAB) including Lactococcal cells have been known to be an effective means of preserving foods, at the same time as giving particular tastes in fields of dairy products. LAB also have always occupied an important place in the technology of sea products, and marine LAB have known to be present in traditional fermented products (Ohhira et al, 1988). To apply the new synthetic medium to marine LAB, two different LAB were isolated from pickled anchovy and pollacks caviar and were grown on the new media in which various concentrations of NaCl $(3, 5, 7 and 10\%)$ added. They were also grown on the medium solution in natural seawater $(35\%o\;salinity)$ and on the solution of natural seawater itself, too. As seen in Fig. 1, Marine LAB were grown best on the synthetic medium solution in natural seawater and the higher concentrations of NaCl were added to the medium, the longer lag-phase of growth profile appeared. Marine LAB in natural seawater were not grown well. From these results, the synthetic medium seems good to cultivate cells which are essential to get salted fish aged. In this study, it showed that the new synthetic medium provided adequate nutrition for L. cremoris KH and KHA1 cells, which have been used as cheese starters (Stadhouders et al, 1988). Using this new medium, the acid production capability of starter cultures could be also measured quantitatively. Thus, this new medium was inferior to the M17 or the modified M17 medium in culturing the cheese starters and in measuring fermentation characteristics of the starter cells. Moreover, this new medium found to be good for selected and well-identified marine LAB which are used in rapid fermentations of low-salted fish.

• Journal of fish pathology
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• v.18 no.2
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• pp.187-195
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• 2005

Effluent of aquaculture industry has caused a growing concern regarding its environmental impact. We assessed the use of flounder farming sewage as supplement of diet, to minimize the impact of aquaculture on the environment or also establish the technique for the recycling of effluent sediment derived from land-based seawater fish farm. In order to investigate the effects of a fermented aquaculture waste on biochemical responses of olive flounder (Paralichthys olivaceus), fermented products of aquaculture wastes were used as test compounds that cause hepatic and renal stress through the induction of oxidative stress in liver and kidney. Hepatosomatic index (HSI), glutathione content and glutathione dependent enzyme were not significantly different and no correlation was found within the different types of fermentation condition or supplement concentration, except for significant increases in 50% fermentation group and 50% concentration group in case of glutathione peroxidase activity and HSI value, respectively. These results showed addition of fermented aquaculture sewage may be an economic artificial sources of diet for fish aquaculture practices without affecting the function and safety in view of biochemical examination.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.4
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• pp.326-335
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• 1988

In order to increase the availability of filefish scrap, the ordinary and low salt sauce were prepared, and identified their taste compounds in their products. To process the filefish scrap sauce, chopped filefish scrap was mixed with koji, 25% brine, slat and glucose (25.0 : 65.0 : 12.5 : 7.0, w/w) and fermented at $25{\pm}4^{\circ}C$ for 120 days. The same process was also carried out to process the low salt sauce adding sorbitol, lactic acid and ethyl alcohol (7.0 : 0.7 : 9.0. w/w) instead of salt. While amino nitrogen and volatile basic nitrogen(VBN) of products were decreased, pH and reducing sugar were increased all alone the fermentation period. The major free amino acids of products at final stage of fermentation were glutamic acid, alanine, leucine, lysine and aspartic acid. And the contents of total amino acid in the ordinary and low salt sauce were 4126.6(mg/100m1 sauce), 4519.5(mg/100m1 sauce) after fermentation. Hypoxanthine was revealed as the major constituent among nucleotides and their related compounds through fermentation. Free amino acid-N in the filefish scrap sauces were from 56.3%(ordinary) to 60.7%(low salted) of extractive nitrogen. From the sensory evaluation, the quality of products from filefish scrap sauce were almost equal to sold soy sauce on the market.

• Journal of Life Science
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• v.28 no.2
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• pp.223-228
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• 2018

Lactic acid bacteria were isolated from a variety of fermented seafoods and sea creatures from the East Sea Rim, Korea and were screened for ${\gamma}-amino$ butyric acid-producing (GABA) activity. Through a 16S rRNA sequence analysis, the bacteria of interest, which were GABA-positive on the thin-layer chromatography analysis, were recognized as three isolates of Lactobacillus (Lb.) brevis and one isolate of Lactococcus (Lc.) lactis. Lb. brevis FSFL0004 and FSFL0005 were isolated from fermented anglerfish and Lb. brevis FSFL0036 was derived from salted cutlass fish. The Lc. lactis strain FGL0007 was isolated from the gut of a brown sole flounder. According to HPLC analysis, the GABA contents produced by FSFL0004, FSFL0005, FSFL0036 and FGL0007 were equivalent to $10,754.37{\mu}g/ml$, $13,082.79{\mu}g/ml$, $12,290.19{\mu}g/ml$, and $45.07{\mu}g/ml$ respectively in 1% monosodium glutamate-supplemented methionyl-tRNA synthetase (MRS) broth. The four strains were inoculated in skim milk with 1% monosodium glutamate to commercialize the strains as starter cultures for GABA-enriched dairy products, and TLC results displayed the production of ${\gamma}-amino$ butyric acid by all four strains in the adaptation media. Lc. lactis FGL0007 demonstrated the greatest GABA production ($431.42{\mu}g/ml$) by HPLC analysis. The GABA production by lactic acid bacteria strains in the skim milk demonstrated in the present study may be helpful for the production of GABA-enriched dairy products.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1408-1418
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• 2013

To investigate the quality properties of functional anchovy fish sauce added with raw sea tangle, 2%, 5%, and 10% (w/w) of sea tangle was added to 25% (w/w) salted anchovy and then fermented at $20^{\circ}C$. During fermentation period, the amino nitrogen contents were increased at all groups and the highest contents were at 450 days of fermentation with $11.99{\pm}0.08$, $12.51{\pm}0.08$, and $11.95{\pm}0.08mg/mL$ at 2%, 5%, and 10% addition of raw sea tangle, respectively. After later, the contents were keeping at a similar level. VBN contents were continuously increased until 270 days of fermentation with $208.10{\pm}3.50$, $210.00{\pm}4.10$, $215.15{\pm}1.50mg/100ml$ at 2%, 5%, 10% addition of raw sea tangle, respectively. Alginic acid recovery was gradually increased in fermentation duration, showed the highest concentration at 540 days of fermentation with 67.00, 67.25, 67.90% at 2%, 5% and 10% addition of raw sea tangle, respectively. Dietary fiber recovery was rapidly increased at the beginning of fermentation and then decreased slowly as the fermentation is progressed. The highest recovery was at 30 days with 18.7, 18.6, and 17.9%, and the lowest was at 360 days with 8.7 and 11.1% at 2 and 10% addition of raw sea tangle, respectively, and 450 days with 11.4% at 5% sea tangle. The lowest fucoidan contents were exhibited at 30 days of fermentation with 0.07% at both of 2% and 5% addition, and 90 days with 0.10% at 10% addtion of sea tangle. The highest fucoidan contents were 270 days showing 0.24, 0.25, and 0.23% at 2, 5, and 10% addition, respectively. All groups adding different sea tangle concentration were not significantly different at all properties. However, the newly developed products were sufficient to the standard guideline of Korea Food Drug Adminstration. The best processing process of functional anchovy fish sauce in addition with raw sea tangle is 2% addition of raw sea tangle and fermented more than 450 days. The results obtained in this study indicated that the fish sauce added with sea tangle is superior in taste, functions to traditional fish sauce and could be competitive fishery fermented food.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.2
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• pp.244-248
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• 2015

We explored the efficiency of natural antibacterial agents used to enhance the self-life and sensory properties of shucked and packed Pacific oyster Crassostrea gigas, which are in high demanded. First, we screened natural resources exhibiting antibacterial activity against food spoilage and pathogenic bacteria. Of theses, ignited oyster shell powder (IOS) and the natural food preservative, lactic acid bacteria fermented powder (LBF), were selected for further study considering the efficacy, mass production, and cost. The addition of 0.1% IOS (W/V) and 0.5% LBF (W/V) to shucked and packed oyster optimally extended the shelf-life without affecting the sensory evaluation. The results obtained in this study will provide a clue to enhance self-life in raw oyster products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.8-15
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• 1997

For an effective use of fish by-products from the skipjack tuna (Katsuwonus pelamis) canning manufactures, the changes of chemical properties of skipjark tuna viscera silage by the processing method during storage were investigated. The acid treated skipjack tuna viscera silage (ASS) were higher in the contents of moisture, lipid, protein and mineral but lower in the contents of carbohydrate and polyunsaturated fatty acids than those of fermented skipjack tuna viscera silage (FSS) by L. bulgaricus, KCTC 3188 and L. plantarum, KCTC 1048. Especially, the contents of total n-3 fatty acids in FSS increased remarkably during storage. The dominant amino acids in ASS and FSS were glutamic acid (Glu), aspartic acid (Asp), leucine (Leu), glycine (Gly) and alanine (Ala). And the contents of tryptophan (Trp) decreased by $30\%$ in ASS and $5\%$ in FSS in comparision with that of raw skipjack tuna viscera after 42 days of storage. The concentration of vitamin $B_1\;and\;B_2$ in FSS increased gradually during storage but the concentration of vitamin $B_2$ in ASS decreased. In the organoleptic evaluation, ASS gave a grayish brown color and a fishy odor. On the other hand, FSS had reddish brown color and sour taste by the production of lactic arid during storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.223-231
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• 1976

Dimethylamine(DMA) is known as an origin compound of dimethylnitrosamine which is responsible for carcinogenesis. It has been also reported that relatively large amount of DMA is distributed in fish muscle, particularly in salted and fermented fish. Tn this experiment, the degradation products of protein and trimethylaminoxide(TMAO) by the temperature conditions of $17^{\circ}C\;and\;27^{\circ}C$ in the course of anchovy fermentation with $22\%$ of salt were analysed, and the formation of DMA was discussed. Protein-N decreased through the whole fermentation period ill the conditions of $17^{\circ}C\;and\;27^{\circ}C$ whereas amino-N increased proportionally to the decrease of protein-N, and the increasing rate of amino-N was remarkably faster at $27^{\circ}C$ than at $17^{\circ}C$. Trimethylamine(TMA) gradually increased with the decrease of TMAO till 69th day of fermentation, hereafter tended to slightly decrease. It seemed that the difference in fermentation temperature affects on the formation of DMA and obviously on the variation of TMAO. Both DMA and TMA content were inversely varied with the TMAO content. Correlation coefficient of DMA to TMAO in quantitative variation was shown -0.811 at $17^{\circ}C$ and -0.865 at $27^{\circ}C$ of fermentation temperature respectively. The results suggested that the formation of DMA during fermentation of anchovy was attributed to the degradation of TMAO showing, contributorial ratio of 0.66 at $17^{\circ}C$ and 0.75 at $27^{\circ}C$ respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.415-420
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• 2010

In Korea, oysters are used as an ingredient of Kimchi (Korean pickled cabbage) in early winter. Although viral contamination of oysters, including contamination by norovirus, can provoke gastroenteric illness, little is known of the epidemiological relationship to outbreaks. We postulated that Kimchi ripening can reduce the infectivity of norovirus, in order to test this hypothesis, we carried out a model experiment. Since norovirus is currently regarded as non-culturable, feline calicivirus (FCV) was used as a surrogate to examine the activation of norovirus with Kimchi ripening. In commercial well-prepared Kimchi, the infectivity ($TCID_{50}$) of FCV decreased by 2 log every 12 hours and reached the limit of detection after 48 hours during over-aging at $25^{\circ}C$. During storage at $4^{\circ}C$, the infectivity ($TCID_{50}$) of FCV decreased slowly and reached 5.00 $TCID_{50}$ after 48 hours. The low pH appears to affect the infectivity of FCV directly via organic acids produced by ripening during over-aging and storage. In neutralized lab-prepared Kimchi (pH 7.0), the infectivity ($TCID_{50}$) of FCV also decreased and reached the limit of detection after 72 hours at $4^{\circ}C$. This indicates that there are substances beside organic acids in Kimchi that originate from the raw materials and are produced during ripening. Among the raw materials, salt-fermented anchovies and garlic showed high direct antiviral activity. The main factor decreasing the infectivity of FCV in Kimchi was the high acidity caused by organic acids, regardless of the type, produced by ripening. Furthermore, unknown secondary products of microorganisms associated with Kimchi ripening and antiviral materials originating from raw material might contribute to the decreased infectivity of FCV, the surrogate of norovirus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.114-118
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• 2001

In manufacturing process of Changran-Jeotgal, agitation with 10 rpm for 10 min/4 hrs of Changran-Jeotgal without released extract was carried out during the fermented process at $0\pm2^{\circ}C$ to shorten the fermentation period and uniform product quality, This step was called Improved process, while the step with release extract and standing fermentation was Conventional process. During 60 days of fermentation period, chemical, microbiological changes and sensory evaluation were examined, Brix, VBN and $NH_2-N$ were 27.4, $54.3\;mg\%\;and\;87.9 mg\%$ on 30th day in Improved process, respectively, but they were 27.1, $57.8\;mg\%\;and\;96.6\;mg\%$ on 50th day in Conventional process. The pH value was decreased from 7.0 to $\6.3\~6.5$ in both of them, The viable cell counts in Improved process was increased from $6.6\times10^3CFU/g\;to\;2.6\times10^6CFU/g$ during 30 days, in Conventional process, slowly increased from $5.8\times10^3CFU/g\;to\;1.9\times10^6CFU/g$ during 50 days. Sensory evaluation showed that products on 30th day in Improved process and products on 50th day in Conventional process were best favorable. From above results, we found that the fermentation with agitation shortened the fermentation period by 20 days compare to standing fermentation.