• Journal of Fisheries and Marine Sciences Education
• /
• v.12 no.2
• /
• pp.213-223
• /
• 2000

In order to establish the exact determination method of amino nitrogen in fish sauces, we compared the amino-nitrogen content in salt-fermented sand lance sauces according to the measuring methods and investigated influencing factors on the procedure of measuring. Amino-nitrogen content was increased in both sand lance sauce during fermentation periods and commercial sand lance sauces. Amino-nitrogen in fermented sand lance sauces for 12 months occupied 88.7% and 75.2% for the trinitrobenzene sulfonic acid(TNBS) method and the Copper-salt method, compare to the Formol method. The ratio of amino-nitrogen/total nitrogen in fermented sand lance sauce for 12 months was higher than in commercial sand lance sauces. The determination of amino-nitrogen by the TNBS method was influenced by concentration of salt in sand lance sauce. The amino-nitrogen content was the highest in the Formol method and followed by the TNBS method and the Copper-salt method without the influence of heating time and monosodium glutamate(MSG) concentration. We concluded that the determination of amino nitrogen in fish sauces was correct to measure with the TNBS method.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.4
• /
• pp.629-634
• /
• 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 Soil Science and Fertilizer
• /
• v.12 no.2
• /
• pp.91-97
• /
• 1979

1. Nitrogenous compounds of-organic materials as nitrogen sources for Korean ginseng were characterized according to their solubility and chemical forms. 2. The extractable fractionation was as follows : Yakto group : non-extractable N > acid hydrolyzable N > acid nonhydrolyzable N > water sol. N, Litter group : acid hydrolyzable N > non-extractable N > water sol. N > acid non-hydrolyzable N, Bone meal : acid hydrolyzable N > water sol. N > acid non-hydrolyzable N. 3. Nitrogenous compounds in the water sol. fraction were : Yakto group and Litter group : humus N > amino acid N > nitrate N (recognized only in Yakto group) > ammonia N > hexosamine N > amide N, Bone meal : amino acid N > humus N > ammonia N > amide N. And nitrogenous compounds in the acid hydrolyzable fraction were : amino acid N > humus N ${\simeq}$ ammonia N > hexosamine N. 4. Availability was discussed about the major nitrogenous compounds (amino acid, humus and inorganic N) and the solubility.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2003.04a
• /
• pp.108.1-108
• /
• 2003

새우젓은 새우와 소금만을 원료로 하여 제조하는데, 최근 수입산 소금의 유입이 급증하고 있어 새우젓에도 이들 수입산 소금의 사용이 늘어가고 있다. 수입산 소금은 수분과 식염함량이 국산 소금과 다를 뿐 아니라 불순물과 무기질 등의 성분 또한 차이가 있다. 본 연구는 소금의 종류가 새우젓에 어떠한 영향을 미치는지 알아보기 위해, 국산천일염, 중국산천일염, 정제염의 세 가지 소금으로 27%의 염농도로 새우젓을 제조한 후 2$0^{\circ}C$ 항온기에서 180일간 숙성 및 발효가 진행되는 동안 이화학적 변화(pH, 염도, 휘발성 염기질소, 아미노태질소, 색상)를 분석하였다. 세 가지 소금의 새우젓 모두 숙성이 진행되면서 단백질 분해 산물인 휘발성 염기질소, 아미노태 질소의 함량이 증가하였는데, 국산 천일염 새우젓이 더 많이 증가하였다. 즉, 숙성 180일 후 휘발성염기질소, 아미노태 질소 함량은 각각 국산천일염 새우젓의 경우 200mg%, 749mg%, 2.3lmg%인 반면, 중국산천일염 새우젓은 67.23mg%, 630mg%, 1.22mg%이었고, 정제염 새우젓은 100.85mg%, 634mg%, 1.76mg%로 나타났다. 지방산패도는 국산천일염 새우젓은 23일(2.450), 중국산천일염 새우젓은 58일(1.771), 정제염 새우젓(2.514)까지 증가한 후 감소하였다. 이상의 결과로 소금의 종류가 새우젓의 숙성에 영향을 미치는 것을 알 수 있었다.

• Culinary science and hospitality research
• /
• v.12 no.4 s.31
• /
• pp.225-235
• /
• 2006

This study was carried out to investigate the optimum conditions for the preparation of natto(unripe Chungkukjang) using Sowonkong(small soybeans) and Bacillus subtilis KCCM 11315. The changes in the contents of amino-type nitrogen, ammonia-type nitrogen, total acidity and total sugar, and those in the pH, browning materials and microbial growth were determined during fermentation and aging of natto(unripe Chungkukjang). The amounts of amino-type nitrogen and ammonia-type nitrogen were increased gradually during the fermentation at $40^{\circ}C$ for 72 hours, but those of total acidity and total sugar were decreased. The pH was gradually alkalized, and more water soluble browning materials were produced during fermentation. The number of viable cells was the highest at the 36 hours of fermentation. The content of ammonia-type nitrogen was significantly decreased during aging at $4^{\circ}C$ for 48 hours. In view of the results as above, it seems possible to conclude that the natto(unripe Chungkukjang) fermented by Bacillus subtilis KCCM 11315 at $40^{\circ}C$ for 36 hours and then aged at $4^{\circ}C$ for 48 hours was suitable for manufacturing natto(unripe Chungkukjang).

• Journal of the Korean Applied Science and Technology
• /
• v.30 no.2
• /
• pp.348-355
• /
• 2013

Squid ink was added to the salt fermented squid by 2% or 4% of concentration and ripened at $10^{\circ}C$ for 8 weeks and at $20^{\circ}C$ for 32days. The effects of the squid ink on the amino nitrogen and muscle protein of salt fermented squid were investigated. The results are as follows; As the salt concentration was decreased and the fermentation temperature raised, amino nitrogen in the salt fermented squid without addition of the squid ink was significantly increased to the latter stage of the ripening and hence fermentations were enhanced. From the change of the protein in the squid muscle in the experiments, dissolution of the myosin heavy chain took place conspicuously in the early stage of the ripening while actin was rarely changed which resulted in the strong resistance to protease. The amino nitrogen content in the salt fermented squid addition of the squid ink has increased to the latter part of the ripening but the range was smaller than no treatment groups. The protein in squid muscle, especially the myosin heavy chain was remarkably dissolved in the middle of the ripening whereas the squid ink added groups of high salt concentration and low temperature showed the tendency of slow proteolysis.

• The Korean Journal of Food And Nutrition
• /
• v.26 no.4
• /
• pp.753-758
• /
• 2013

This study evaluated the quality characteristics for optimization of premix-type Buckwheat (Fagopyrum esculentum) Soksungjang (BS). First, according to the amount of salt (8, 10, 12%), coliform counts were not detected in BS with 10 or, 12% salt at 21 days and Bacillus subtilis HJ 18-4 as a starter at 7 days. Therefore, 10% salt with starter culture might be considered as suitable conditions for safety. Second, according to the ratio of water (1:1, 1:1.5, 1:1.8), BS prepared with the same weights of meju powder and water showed the highest aminotype nitrogen content (688.76mg%) at 35 days; thus, an adequate fermentation state was established at this condition compared to others. Third, according to the type of container (pot, plastic, glass), the aminotype nitrogen contents were higher in the plastic container and pot than in the glass bottle. Lastly, according to the batch size (1.25, 2.5 kg), the coliform of the 2.5 kg sample decreased faster than that of 1.25 kg samples at 14 days. These results suggest that BS prepared with the same ratio of water and meju powder fermented with HJ 18-4 as a starter and 10% salt in a pot, plastic container (3 weeks) and glass container (4 weeks) showed desirable fermentation qualities.

• Applied Biological Chemistry
• /
• v.47 no.2
• /
• pp.176-181
• /
• 2004

This study was carried out to investigate the effect of yucca extract on the quality characteristics of Chungkookjang using Bacillus subtilis p01. The changes in the contents of amino-type N, ammonia type N, volatile compounds and organic acids, and those in the activities of ${\alpha}-amylase$ and protease were also determined during aging of Chungkookjang. The amount of amino-type N increased gradually with time for aging. The content of amino-type N was slightly higher in Chungkookjang fermented by adding yucca extract than in the control without yucca extract. The content of ammonia-type N was slightly lower in Chungkookjang with yucca extract than in the control without yucca extract. The activities of amylase and protease were higher in Chungkookjang with yucca extract than in the control and the highest in Chungkookjang containing 0.5 mg/g of yucca extract. Organic acid contents in Chungkookjang was the highest at the initial period of fermentation. The contents of organic acids in Chungkookjang with yucca extract was higher than that in control for 48 hr of aging. The amounts of 2,5-dimethylpyrazine were increased by addition of yucca extract, while those of cis-3-hexanol were decreased.

• Applied Biological Chemistry
• /
• v.15 no.2
• /
• pp.93-109
• /
• 1972

Three lots of Chung-Kook-Jang were prepared by the use of 2 strains of Bacillus subtilis and Bacillus natto. For four samples taken from each lot in 12 hrs interval changes of nitrogenous compounds, insoluble protein, water soluble protein, peptides, free amino acids, amino and ammonia nitrogens during Chung-Kook-Jang fermentation, were studied together with the changes of moisture, pH, proteolytic enzyme activity. In addition the average peptide length of the peptides of a Bacillus subtilis lot was determined by the method of molecular sieving using ion exchange resin. The results were as follows: 1. The contents of moisture and total-nitrogen changed little in all samples throughout the fermentation as it would be expected. 2. In all three experimental lots the pH became higher gradually from the initial value of 6.65 to the final $7.5{\sim}7.85$ during the fermentation. Proteolytic enzyme activities, in accordance with this pH change, steadily increased up to $48{\sim}60$ hrs. of fermentation and then slightly decreased, probably affected by the high pH. The most strong proteolytic activity was observed in the experimental Chung-Kook-Jang fermentation lot using the Bacillus subtilis K-27 isolated by the author. 3. The contents of insoluble protein nitrogen in soybeans increased markedly (5%) by the cooking, after steeping 12 hrs in water. During the Chung-Kook-Jang fermentation, however, it decreased from 1/2 to 1/10 of that of the cooked soybeans. 4. The contents of water soluble protein nitrogen (5%) whereas, greatly decreased to the value of 1.0% by the cooking; but little changed further during the fermentation, 5. The total contents (0.25%) of peptides, amino, and ammonia-nitrogens, PAA-N., increased almost double by the cooking and steadily became higher as the fermentation proceeded, reaching finally up to$4{\sim}7%$ in 72 hrs fermentation. 6. The amounts of free amino acids of soybean generally decreased during the processing of cooking, even some of them like glutamic acid were destroyed completely, However in the subsequent Chung-Kook-Jang fermentation for 72 hrs., they showed from several to a few hundreds folds increases depending upon the kinds of amino acids. Valine which was contained in HCl-hydrolyzed steeped or cooked soybeans in amounts $220{\sim}267mg%$ was not detected at all as the free amino acid in all fermented samples. 7. Average peptide length (APL) of all fractions, eluted and fractionated by using the Dowex-50 ion exchange resin column, and fraction collector showed the highest value for the cooked soybean and then decreased as the fermentation proceeded. The APL value of effluent showed the highest in 12 hrs fermented sample, The value decreased thereafter by fermentation.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.8 no.2
• /
• pp.101-106
• /
• 1975

Following the previous report(Kang et al, 1974), the conditions of cooking for shelling process of oyster were discussed, and the content of nitrogenous compounds in the cooked-released fluid of oyster by different cooking conditions has been investigated. The heating condition of $110^{\circ}C$ and 15 minutes was adequate for effective shelling and the condition of meat content in cooking of oyster. The contents of total nitrogen, protein nitrogen, nonprotein nitrogen and amino-nitrogen were seemed to be increased with heating time, and the tendency was to be more exact in the cooking condition of $110^{\circ}C$. The content of nitrogenous compounds at the cooking condition of $110^{\circ}C$ and 15 minutes was determined: total nitrogen, $225.6\;mg\%$ protein nitrogen, $54.4\;mg\%$; amino-nitrogen, $89.2mg\%$. The content of free amino acid was also analysed: arginine, $26mg\%$; histidine, $12.1mg\%$; tyrosine, $2.7mg\%$; leucine, $2.2mg\%$; lysine, $1.9mg\%$ Trace amounts of glutamic acid, isoleucine, serine, threonine, and glycine were detected.