• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.636-641
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• 1995

Proteolytic activities were compared using three species involving in squid jeotkal fermentation and showing positive reaction upon casein test : Pseudomonas D2, Flavovacterium odoratum and Acinetobacter calcoaceticus. Pseudomonas D2 produced highest activity of protease at 72h when incubated in our own modified medium(polypeptone, 0.5% ; tryptone, 0.5% ; NaCl, 3% ; pH, 7.5). Thus, this specie was selected for the further study. The growth pattern was coincided with the production of protease. Thus purification of protease was proceeded by ethanol precipitation, sephadex G-100 gel filtration, and DEAE sepharose ion exchange chromatography. The purified protease showed highest activity at pH 7.0 and 5$0^{\circ}C$. The enzyme was very stable over the wide ragnes of the temperature ; even with one hour heat treatment at 7$0^{\circ}C$, the enzyme showed substantial amount of the activity toward casein. In addition, the enzyme was stable over the wide range of pH. Molecular weight of the protease was determined to be 17.4 kD by SDS-PAGE.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.721-729
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• 2013

To improve the quality and functionality of the low salt squid Jeot-gal, extracts from three types of medicinal and edible plants (bay leaf, green tea, pine needle) were added. The quality characteristics, bioactivities, and shelf-lives of these preparations were determined at three different fermentation temperatures. The pH decreased more rapidly at higher temperatures, while the amount of volatile basic nitrogen (VBN), total viable cells, and amino nitrogen ($NH_2$-N) increased. The shelf-lives of Jeot-gal with natural plant extracts at $10^{\circ}C$ were 34~35 days, similar to the control. The major free and compositional amino acids of Jeot-gal were glutamic acid, proline, and alanine, while the major nucleotides (and related compounds) were hypoxanthine and inosine. In bioactivity assays, samples supplemented with plant extracts showed higher bioactivities than the control. The DPPH radical scavenging activity of ethanol extracts from Jeot-gal were stronger than the water extracts; in contrast, the water extracts were stronger for hydrogen peroxide scavenging activity. However, superoxide dismutase (SOD)-like activity and ${\beta}$-glucuronidase inhibitory activity were moderately low at 20 mg/mL. Based on sensory evaluation results, the quality of low salt squid Jeot-gal with natural plant extracts is similar to the control. Therefore, low salt squid Jeot-gal with natural plant extracts can be commercialized as a functional fermented food.

• Journal of Food Hygiene and Safety
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• v.17 no.4
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• pp.173-177
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• 2002

It was performed to survey bacterial distribution on 72 salted fermented fishery products in Seoul Garak wholesale market from April to May in 2002. In average values of biological aspects, salts were 17.2%, in microbiological aspects (Unit: CFU/ml, bacterial cell count 4,900, coliforms 44, Vibrio spp., 160, Staphylococcus spp., 3,000 respectively. Of 93 isolated cells, coliforms were 35.5% (33/93), Vibrio spp. 8.6% (8/93) and Staphylococcus spp. 12.9% (12/93). E. cloacae was the highest (15/33) in coliforms, V. alinolyticus were the most (each 5/8) in Vibrio spp., In case of Staphylococcus spp., S. lentus was the best (5/12).

• Journal of Food Hygiene and Safety
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• v.15 no.1
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• pp.13-17
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• 2000

The low salt seasoned jeotkal, salted and fermented fisheries product, may has some problems, such as short shelf-life, its putrefaction by mixing some microorganism from additives. It was considered that most microorganism in seasoned jeotkal were introduced from red pepper powder. Therefore, it is important to pasteurize red pepper powder for improving its microbial quality. When red pepper powder was pasteurized by ohmic heating, the survival cell concentration in red pepper powder was reduced to 1-log-unit at 500 V/m, 700 V/m, above 8$0^{\circ}C$. But viable cell counts were reduced from 8.5$\times$10$^{6}$ CFU/g to 2.1 $\times$ 10$^2$CFU/g, i.e. 4.6-log-unit, during ohmic heating at 9$0^{\circ}C$ for 40 min. Color values of red pepper powder during ohmic heating with different holding time were not changed significantly. When squid-jeotkal was manufactured by using the pasteurized red pepper powder, viable cell counts of the product were decreased by about three log cycles, compare with control product. And also the counts of fungi were significantly decreased.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1619-1627
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• 1999

Microbiological characteristics of gamma irradiated low salt squid Jeot-gal were examined. Following the fermentation periods, total bacterial cell, Lactobacillus spp., Staphylococcus spp., Streptococcus spp., Pseudomonas spp. and yeast cell number were counted on their selective media and some acid forming bacteria and Pseudomonas spp. were identified. As the gamma irradiation dose increased, the microbial density of early fermentation phase was reduced and the growth rate was delayed. The repression effects on microbiological growth by gamma irradiation were to be higher as salt concentration increased. Adequate conditions of salt concentration and gamma irradiation for low-salt squid Jeot-gal preparation were 10% and 10 kGy, respectively. Lactobacillus sp. 2, Micrococcus varians and Streptococcus sp. I were isolated from 5% salt containing squid Jeot-gal, and Micrococcus morrhuae was from 20% only while Lactobacillus plantarum and Lactobacillus brevis were widespread. Lactobacillus brevis, Pediococcus halophilus and Pseudomonas diminuta were sensitive and Lactobacillus plantarum, Micrococcus morrhuae and Pseudomonas sp. 3 were resistant to gamma irradiation. The diversity of microflora decreased as salt concentration decreased and gamma irradiation dose increased.

• Journal of the Korean Applied Science and Technology
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• v.30 no.3
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• pp.488-493
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• 2013

This study shows the effect of 4% squid ink on the textural properties of squid during fermentation for 8 weeks at $10^{\circ}C$ or 32 days at $20^{\circ}C$ in 5% salt solution. Although the hardness and chewiness of the squid fermented with squid ink continuously decreased during fermentation, the degree of decrease was smaller than that of squid fermented without squid ink. We can conclude that squid ink inhibited the ripening of the low salt fermented squid.

• Journal of the Korean Applied Science and Technology
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• v.28 no.4
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• pp.517-525
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• 2011

Squid ink was added to the low salt fermented squid by 4% of concentration and ripened at $10^{\circ}C$ for 6 weeks and at $20^{\circ}C$ for 28 days. The effect of the squid ink on the titrable acidity and free amino acids of low salt fermented squid were investigated. The results are as follows; The titrable acidity in the salt fermented squid without addition of the squid ink was continuously decreased except for the salt fermented squid with 9% salt content till the latter stage of the ripening, had larger decreasing range than treatment groups. Seeing the composition of free amino acid, the major amino acids are proline, arginine, glutamic acid. leucine and glycine.

• Journal of the Korean Applied Science and Technology
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• v.20 no.1
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• pp.64-71
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• 2003

Squid ink was added to the low salt fermented squid by 4% of concentration and ripened at 10$^{\cric}C$ for 6 weeks and at 20$^{\cric}C$ for 28 days. The effect of the squid ink on the non-volatile organic acids of low salt fermented squid were investigated. The results are as follows; The non-volatile organic acid in the salt fermented squid without addition of the squid ink was examined and the result showed that lactic and acetic acids were the major organic acids even if very small amount of citric and oxalic acids were detected. In the squid ink added to the low salt fermented squid, total quantity of non-volatile organic acid in the latter part of the ripening was lower than no treatment groups.

• 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.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.42-47
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• 1986

The fatty acid composition of lipids extracted from 18 kinds of salted and fermented sea foods which have been consumed in Korea were examined. The lipid contents of salted and fermented sea foods showed wide difference (0.8-11.9%) depending on species and portions of raw materials. In fatty acid composition of salted and fermented sea foods prepared with whole fishes, the saturated fatty acid was the most predominant component, and the major fatty acids were 16:0, 18:1, 22:6, 16:1 and 20:5. In case of salted and fermented products prepared with gills, roe or intestines, the polyenoic fatty acid was the main component, the major fatty acids were 18:1, 16:0, 22:6, 20:5, 16:1 and 18:3. In these products the composition ratios of 20:5 and 18:3 were higher, and that of 16:0 and 16:1 were slightly lower as compared with salted and fermented whole fish products. And in case of salted and fermented crustacea and mollusk, the polyenoic fatty acids such a 22:6 and 20:5 were the most predominant component, the abundant fatty acids were 22:6, 16:0, 20:5, 18:1 and 16:1. Judging from results, salted and fermented sea foods were abundant of the highly unsaturated fatty acids such as 20:5, 22:6 inspite of the long fermentation periods.