• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1333-1338
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• 1998

Several enzymes of kimchi ingredients were assayed to improve the product quality using these quality related enzyme information. Among various hydrolases, amylase and protease were selected with respect to lactic acid fermentation. Peroxidase and ascorbic acid oxidase were studied for off flavor production and ascorbic acid destruction. The amount of protein in kimchi ingredients, specific and total enzyme activity of sample were compared. Regarding total enzyme activity of sample, ${\alpha}-amylase$ activity of salted and fermented anchovy, dried red pepper and salted and fermented shrimp were higher than other ingredients. Activity of salted and fermented anchovy was 2,790.0 units/g sample. Salted and fermented anchovy, oyster and Chinese radish showed the highest ${\beta}-amylase$ activity (4.4, 2.1, 1.0 units/g sample, respectively). Salted and fermented anchovy showed the highest protease activity of 13.4 PU/g sample, followed by salted and fermented shrimp and dried red pepper. For peroxidase, Chinese radish, cucumber, green onion showed the highest activity of 7.2, 6.8 and 5.6 units/g sample, respectively. In case of ascorbic acid oxidase, salted and fermented anchovy showed the strongest enzyme activity (331.4 units/g sample), followed by dried red pepper and salted and fermented shrimp.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.53-59
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• 2008

Salt is a major component in salt-fermented shrimp with 25% content. There are various types of salts that have different compositions, which may affect the quality of salt-fermented shrimp. We have investigated effects of various salts such as Korean solar salt (KSS), purified salt (PS), sea-concentrated salt (SCS), glasswort (Salicornia herbacea L.) spray solar salt (GSS), glasswort-sea-concentrated salt (GSCS) and spray-dried salt (SDS) on the physicochemical and sensory properties of fermented shrimps. Ammonia nitrogen content of the salted shrimp prepared with SDS was lower than others until 60 day fermentation. At 90 day fermentation, amino nitrogen contents of salted shrimps prepared with GSCS and GSS (980 mg%) were higher than those of the others while sample prepared with SDS showed the lowest amino nitrogen content (680 mg%). Volatile basic nitrogen content of salted shrimp prepared with SDS was also lower than those of the others between 14 and 60 day fermentation and there were differences among samples in the contents of trimethylamine at 180 day fermentation. Sensory evaluation results indicated significant differences in salty, overall taste and overall acceptance among samples. Overall acceptance was significantly higher in salt-fermented shrimp prepared with KSS, SCS, GSS, GSCS and SDS than in fermented shrimp with PS.

• Food Science of Animal Resources
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• v.34 no.1
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• pp.99-105
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• 2014

The aim of this study is to evaluate the availability of salted and fermented fish (SFF) including salted and fermented anchovy (SFA) and shrimp (SFS) as a marinade of beef jerky. In curing solutions, half (SFA 1 and SFS 1) or whole (SFA 2 and SFS 2) salt-water was replaced with SFF juices. Higher water activity ($a_w$) was found in the beef jerky cured with SFFs than the control (C) (p<0.05). The SFFs had the effect of causing a decrease in hardness and an increase in cohesiveness (p<0.05). Among the treatment samples, springiness was the highest in SFA2 and SFS2 (p<0.05) and the lowest values of Warner-Bratzler shear force were found in SFA1 and SFA2 (p<0.05). The SFFs also had the effect of increasing the flavor of the sensory properties; however, color measurements from both the instrumental surface color ($L^*$, $a^*$, $b^*$, chroma, and hue angle) and color of sensory evaluation were decreased by addition of SFFs (p<0.05). Therefore, we conclude the SFFs can improve the texture and sensory properties of the beef jerky. In particular, the SFS is a good ingredient for the curing solution. However, studies are still needed on improving the $a_w$, pH, and surface color of the beef jerky to apply the SFFs for making beef jerky.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.919-924
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• 2008

The aim of this study was to observe the changes in allergenicity of saeujeot (salted and fermented shrimp) using a competitive indirect enzyme-linked immunosorbent assay (Ci-ELISA). The fermentation conditions tested for saeujeot consisted of various temperatures (25, 15, and $5^{\circ}C$) and salt concentrations (25, 15, and 10%). When saeujeot was fermented at a low salt concentration and high temperature, the binding ability of mAb and shrimp-allergic patient serum to allergen was significantly decreased. In particular, the binding ability of mAb to allergen in saeujeot fermented with 10% salt at $25^{\circ}C$ for 5 days decreased to 5%. Also, the binding ability of shrimp-allergic patient serum to allergen in saeujeot fermented for 5 days with 10% salt at $25^{\circ}C$ was 8%. In conclusion, the binding of mAb and shrimp-allergic patient serum to tropomyosin in saeujeot decreased with longer fermentation periods, lower salt concentrations (10%), and higher temperatures ($25^{\circ}C$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1302-1309
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• 2016

N-Nitrosodimethylamine (NDMA) is formed through reactions between dimethylamine (DMA) and nitrite. Jeotgal, a traditional Korean salted and fermented seafood, contains a large amount of DMA and is an ingredient of kimchi condiment. This study investigated the effects of amount and type of Jeotgal on changes in NDMA and its precursor contents during storage of kimchi. NDMA was found in all 23 Jeotgal samples, and DMA in nine salted and fermented shrimp samples showed levels ranging from 16.5 to 58.9 mg/kg (average of 30.9 mg/kg). The seven salted and fermented anchovy juice samples showed DMA levels ranging from 21.7 to 44.4 mg/kg (average of 34.5 mg/kg). Kimchi was assigned to one of the following five groups: kimchi without salted and fermented anchovy juice and salted and fermented shrimp (control), kimchi with small amount of salted and fermented anchovy juice (AK1), kimchi with large amount of salted and fermented anchovy juice (AK2), kimchi with small amount of salted and fermented shrimp (SK1), and kimchi with large amount of salted and fermented shrimp (SK2). SK2 had higher DMA content than SK1 during storage while AK2 had higher DMA content than AK1 after storage for 10 days. Nitrite contents of AK1 and SK1 were higher than those of AK2 and SK2 after storage for 20 days. NDMA content was significantly higher in SK2 than in SK1 after storage for 0 and 10 days, and NDMA content in AK2 was significantly higher compared to that in AK1 after storage for 0 days. The DMA and NDMA contents decreased in all kimchi samples during storage. The effects of amount and type of Jeotgal on DMA and NDMA contents were reduced after storage for 20 days. The results suggest that the content and type of Jeotgal have significant effects on formation of NDMA in kimchi.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1107-1113
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• 2000

Gamma irradiation technology was applied to develop salted and fermented shrimp with lower salt concentration, high sensory quality and storage stability. Shrimp was prepared with 15 and 20% of salt and fermented at $15^{\circ}C$ for 10 weeks. The sample was irradiated at 0, 5.0 and 10.0 kGy right before optimum stage of fermentation. Fermented shrimp with 30% of salt concentration was also prepared as a control. The proximate composition, salinity and Aw were not affected by gamma irradiation. However, pH of irradiated samples was lower than that of non-irradiated samples, probably because irradiation effectively suppressed excessive fermentation by controlling microorganisms. From the results of sensory analysis, it was concluded that fermented shrimp with 15% of salt and irradiated at 10 kGy before optimum fermentation, or 20% of salt and 5 kGy or above were the most effective in terms of sensory quality and storage stability.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.349-355
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• 2000

This study was conducted to enhance the storage stability of fermented shrimp with different salt contents using a high hydrostatic pressure. The effects of the magnitude of pressure and treatment time on the microorganisms of the fermented shrimp were investigated. The highest microbial counts with respect to the salt levels were observed at 18% salt, showing $3.4{\times}10^5\;CFU/g$ for general bacteria, $6.4{\times}10^4\;CFU/g$ for halophilic bacteria, $4.2{\times}10^5\;CFU/g$ for yeast and $3.0{\times}10^4\;CFU/g$ for halophilic yeast. The degree of sterilization increased with the magnitude of pressure and treatment time, and the sterilization could be analyzed by the first order reaction kinetics. The sterilization rate constants $(k_p)$ of the halophilic bacteria was lower than that of general bacteria. The $log(k_p)$ increased linearly with pressure and the slope of the regression line of the halophilic bacteria was greater than that of general bacteria, indicating that the sterilization of the halophilic bacteria was more dependent on the pressure. High hydrostatic pressure treatment was an effective non-thermal sterilization method for the salted and fermented shrimp, and the optimum treatment condition was for 10 min at 6,500 atm.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.629-634
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• 2000

The effects of gamma irradiation on changes of chemical compounds of fermented shromp with low salt were studied. The shirmp was salted NaCl concentration of 10%, 15% and 20%, and irradiated at 0, 2.5, 5.0, 7.5 and 10.0kGy. Amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA) and neutral protease acivity were examined during ferentation at 15$^{\circ}C$. A sample with 30% salt concontration was also prepared as a control. The initial contents of AAN, VBN, TMA and protease acitivity were not affected by gamma irradiation. The contents of AN, VBN and TMA were incteased with fermentation period. But, the more increased NaCl concentrations and the higher irradiation dose, the loss increased content of chemical compounds and protease activity were found. Protease was increased until 4~5 weeks and then decreased gradually. The results showed that the chemical compounds and protease activity of salted abd fermeted shrimp prepared with 15% NaCl contentration and 10 kGy irradiation dose, or 20% and 5 kGy or higher were maintained the appropriate level of quality up to 10 weeks of storage compared with the control.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.187-191
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• 2000

This study was performed to examine the effects of salt addition level on the changes in physicochemical properties of the salted and fermented shrimp during fermentation. Amino nitrogen content increased with the fermentation time, and was higher at low salt addition level. Volatile basic nitrogen content in the fermented shrimp with 3 and 8% salt increased rapidly at initial fermentation period, but decreased at 6 week fermentation and remained constant afterward, while that with 18 and 30% salt maintained its initial level through 22 week fermentation. Thiobarbituric acid(TBA) value decreased rapidly in the early stage of the fermentation, but slightly increased after 4-6 week fermentation. The TBA value was higher at lower salt level after 6 week fermentation. Peroxide value of the fermented shrimp with salt content higher than 8% increased rapidly at 2-4 week fermentation and decreased sharply at 6 week, while that with 3% salt showed the maximum value at 10 week fermentation.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1191-1195
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• 1997

This study was conducted to investigate the proteolytic properties of saewoojeot (salted and fermented shrimp) on various meat proteins. NaCl content was decreased less than 2% by electrodialysis. As electrodialysis time was passed, the protease activity was increased. The proteolytic activity of crude protease on muscle proteins of beef, pork, chicken was analyzed by SDS-PAGE. Crude enzyme easily degradated both heat-denatured and native meat proteins. Protein degradation was rapidly occurred within 5 min and most all myofibrilar protein was disappeared. Heat-denatured chicken meat (100%) was most easily degraded than heat-denatured pork meat (47%) and beef meat (31%).