• 한국환경과학회지
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• 제22권6호
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• pp.723-732
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• 2013

This study was carried out to investigate changes of protease and amylase activities and nitrogen content in Chungkookjang prepared by Bacillus subtilis S8 and different soybean. Amino-type nitrogen and ammonia-type nitrogen contents increased with an increase in fermentation time and was the highest in black soybean Chungkookjang. The number of viable cells increased up to 24 h of fermentation at all temperatures tested; especially, their levels were the highest at $40^{\circ}C$. Protease activity was the highest in black soybean Chungkookjang. ${\alpha}$-amylase activity increased significantly up to 6 h of fermentation at $30^{\circ}C$ and $40^{\circ}C$ and then maintained constantly. It also increased up to 30-36 h of fermentation at $45^{\circ}C$ and then decreased. ${\beta}$-amylase activity was the highest in black soybean Chungkookjang at $35^{\circ}C$ and $40^{\circ}C$ and in yellow soybean Chungkookjang at $45^{\circ}C$. Production pattern of reducing sugar was similar to that of ${\beta}$-amylase. Amino-type nitrogen, viable cell number and reducing sugar content and ${\beta}$-amylase activity was the highest in Chungkookjang fermented at $40^{\circ}C$. Considering amino-type and ammonia-type nitrogen contents, Chungkookjang fermentation using yellow soybean was favorable. However, the fermentation using black soybean was favorable, considering protease and amylase activities and reducing sugar content.

• 한국작물학회지
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• 제29권3호
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• pp.242-253
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• 1984

종실의 품질특성이 어떻게 변화하는가를 구명하기 위하여 라맥 품종중 찰성인 요네자와와 메성이며 대립인 백동과 소립인 영산보리를 재료로 질소시용량을 달리하여 수행한 시험에서 얻은 몇가지 결과를 요약하면 다음과 같다. 품질의 변화를 보면 질소증시에 의해 단백질은 증가하며 백동이 배비구(N$_1$)에서 13.7%로써 가장 높았고 출수후 성숙이 진전됨에 따라 단백질 함량은 출수 직후에 높다가 4주째에 가장 낮은 함량을 보이다가 다시 증가하였다. 단백질의 solubility fraction에서 glutelin 함량이 최고이며 질소시용량이 증가할수록 증대되었다. amino산중 lysine함량은 요네자와와 백동이 영산보리보다 높으며, 질소시용량이 증가함에 따라 모든 공시품종에서 현저한 증가를 보였다. proline은 타 amino산에 비하여 월등하며 질소수준이 증가할수록 증대됨을 알 수 있었다. 질소증시에 의하여 무기성분중 Mg, K는 감소하고 Ca는 증가하였다. 회분은 질소 증시에서 감소하고 성숙이 진전함에 따라서 감소하였다. 질소시용량이 증가할수록 맥입의 경도가 낮아지고 호분층이 연해지기 때문에 도정율을 낮추어야 하며 찰성인 요네자와는 메성인 두 품종보다 적게 도정하여야 함을 알 수 있다. 도정시간이 길면 가열흡수율이 높으며 도정률 60%로 기준하여 보면 찰성인 요네자와가 메성인 두 품종보다 가열흡수율이 높고 밥의 백도도 찰성인 요네자와가 메성인 두 품종보다 높고 질소시용량이 증가할수록 밥 백도가 백동, 영산보리에서는 낮아졌으나, 찰성 인요네자와에서는 높아졌다. Amylogram의 점성에서 호화온도는 찰성이 46.$0^{\circ}C$로 메성 58.$0^{\circ}C$ 보다 낮고 질소시용량과 큰 관계가 없으며 최고점도는 찰성인 요네자와가 보비구에서 2000BU, 메성인 백동은 무비구(No)에서 1020BU로서 찰성이 메성 보다 높고 질소시용량이 증가될수록 높아졌다. 찰성은 메성보다 호화온도가 낮고 최고점도는 높았다.

• 한국수산과학회지
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• 제48권3호
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• pp.275-283
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• 2015

This study compared the sensory and nutritional characteristics of mottled skate Beringraja pulchra caught off Ulleung Island (U-MS), Korea, with those caught off Daecheong Island (D-MS). Based on their trichloroacetic acid-soluble nitrogen content, free amino acid content, and taste value, the taste of intermediate weight female U-MS was superior to that of both other U-MS and D-MS. The urea content of U-MS was higher in females than males and increased in the order heavy>intermediate>light individuals. There was, however, no difference in urea content between U-MS and D-MS. The taste and flavor characterization results suggest that the level of ammonia, which was converted from urea, influenced the quality of fermented U-DS. With the exception of the light U-DS, the other U-MS exhibited no difference in terms of hardness. The total amino acid content of U-MS was higher in females than males and increased in the order intermediate > heavy > light individuals. The total amino acid content of U-MS was also higher than that of D-MS. The major amino acids of all MSs were aspartic acid, glutamic acid, leucine, and lysine.

• 한국수산과학회지
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• 제54권1호
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• pp.1-8
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• 2021

In order to develop value-added low-salt fermented seafood with a long shelf-life, we prepared seasoned low-salt fermented Mideoduck (Styela clava) supplemented with fermentation alcohol (SME). The SME was produced by washing and dewatering shelled Mideoduck, followed by cutting and salting for 24 h at 0℃. The salted Mideoduck was seasoned and fermented with ingredients, including garlic, ginger, monosodium glutamate, red pepper, sesame, sorbitol and sugar, for 7-8 days at 0℃. After adding 3-5% fermentation alcohol, the Mideoduck was packed in a polyester container. The salinity, volatile basic nitrogen, and amino nitrogen content of the SME was 4.5%, 20.9 mg/100 g and 92.0 mg/100 g, respectively. In comparison with the control, the addition of 3-5% fermentation alcohol showed inhibitory effects of decreased freshness, texture degradation, and growth of residual bacteria. Additionally, the SME had good storage stability and organoleptic qualities when stored at 4±1℃ for 40 days. Therefore, it is suitable for commercialization as a seasoned low-salt fermented product with a long shelf-life. The total amino acid content of the SME was 11,774.5 mg/100 g, majorly comprising glutamic acid, aspartic acid, lysine, arginine, and leucine, and the free amino acid content was 506.4 mg/100 g, majorly comprising hydroxyproline, taurine, and glutamic acid.

• 한국수산과학회지
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• 제3권4호
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• pp.207-212
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• 1970

멸치절임의 숙성 및 저장 중의 효소 활성 VBN, 세균수, 식염 함유량, 산도, amino-N pH 그리고 지방의 산가에 다음과 같은 결과를 얻었다. 1) Protease 활성은 염수 염장 중에는 증가하고 절임 중에는 식초산의 영향으로 감소하고 이후 차차 거의 일정하게 변화하며 이에 따라 amino-N는 대개 증가하여 숙성한다. 2) Lipase 활성은 염수 염장 중에는 감소하며 vinegar의 첨가로 일단 증가하였다가 절임중에는 증감의 일정한 경향을 볼 수 없다. 그리고산도는 대개 증가하고 있다. 3) VBN와 NaCl 농도는 염수 염장 중에는 급격히 증가하고 절임중에서는 VBN는 완만한 증가를 하며 NaCl 농도는 기의 변화가 없었다. 4) 세균수는 염수 염장함으로써 줄었다가 다시 증가하며 절임함으로써 급격한 감소를 보이고 그 이후에는 일정한 수를 유지 하였다. 5) 절임 제품의 저장성을 유지하기 위해서는 육질의 산도가 $2\%$ 이상이 되도록 vinegar의 산도를 높혀 주어야한다. 6) 염수 염장하는 기간은 8일이 적합하였으며 VBN, 산도, amino-N, lipase 활성 및 관능 검사 성적을 보아서 절임한 후 47일까지 보장할 수 있고 32일 때가 가장 맛이 좋았다.

• 한국식생활문화학회지
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• 제14권5호
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• pp.461-466
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• 1999

As a part of investigation to use sardine(Sardinops melanoslicta) more effectively as a food source, this study was undertaken the processing condition of rapid- and low salt-fermented liquefaction of sardine. To prepare rapid fermented products, the chopped whole sardine was added 8% NaCl and then preheating treatment at $40^{\circ}C,\;45^{\circ}C$ and $50^{\circ}C$ in the manufactured fermenter(180L) for 9 hrs, and then fermentation at $33^{\circ}C$ for 90 days. The chemical changes such as amino nitrogen(amino-N), volatile basic nitrogen(VBN), and histamine in the hydrolysates of fermented sardine were analyzed as well as viable cell count and organoleptic evaluation during fermentation to compare the quality between control and preheating samples. During fermenting, the amino-N in the hydrolysates increased rapidly during the first 30 days and slowly thereafter. The highest content of amino-N appeared at 75 days in control sample and $60{\sim}75$ days in preheating samples. The changes of VBN in the hydrolysates increased rapidly during first 15 days in control samples and 30 days in preheating samples. However they were generally low level in preheating samples. Histamine content in the hydrolysates of the control samples increased markedly after 15 days, but preheating samples were generally low level, and then $75{\sim}90$ days of fermentation reached to the maximum which was about $2.0{\sim}3.0$ times lower than that of control samples. As for the organoleptic flavor evaluation, the control and preheating at $40^{\circ}C$ samples were unpleasant odor after 15 and 60 days, respectively. But preheating at $45^{\circ}\;and\;50^{\circ}$ samples were fresh odor after 90 days fermentation.

• 한국식품영양학회지
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• 제32권6호
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• pp.598-610
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• 2019

The purpose of this study was to investigate the quality characteristics and antioxidant activity by collecting four times on six samples of Jeonbuk regional soybean pastes (Doenjang) traditionally prepared for this study. The water content of samples decreased according to progress of the aging period and the water content of the fourth sample collected was 42.40~59.64% (p<0.05). The salinity of the fourth Doenjang samples was 11.80~18.60%. The amino-type nitrogen content was 122.67~540.33 mg% immediately after the preparation of Doenjang in the Jeonbuk region and the content of the fourth collection samples increased from 251.49 to 982.36 mg% (p<0.05). The isoflavone glycosides decreased but daidzein, genistein and glycitein, which are aglycones, increased during aging periods. The total polyphenol content of the fourth collected samples was 11.99~19.27 mg GAE/g (p<0.05). The DPPH radical scavenging activity, ABTS radical scavenging activity and FARP of the fourth Doenjang samples were 51.88~81.21%, 84.14~90.32%, and 1.08~3.11 mg Trolox/g, respectively. As a result of quality analysis on Doenjang, the superiority of traditional Doenjang has been proven by the increase of amino nitrogen content and antioxidant activity according to the aging period. However, factor analysis on quality differences of regional Doenjang should be conducted to ensure standardization and quality improvement.

• 한국식품조리과학회지
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• 제15권2호
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• pp.95-101
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• 1999

This study was carried out to prepare green teas by traditional roasting manufacturing process, Ku Geung Ku Po and to determine the quality charateristics of the green teas by examining the change of their main components induced during this roasting process. The content of total sugars in unroasted tea leaves was 7.82%. Its content of roasted teas was decreased by increasing the number of roasting and there was significantly differences between samples. The content of total sugars in 9th roasted green tea was 3.98%. The total nitrogen contents of green teas produced by this process were 4.96∼6.38%. The more the number of roasting and the less content of tannin in green teas. And the ratio of total nitrogen and tannin in tea leaves 21.97 but its ratio in 9th roasted tea was increased to 45.54. The ascorbic acid in tea leaves consisted in 1,820.3 mg/100g but its content was decreased by increasing the number of roasting process. Whereas the content of caffeine in green teas was not reduced significantly by this traditional method. Of all amino acids, green tea produced by Ku Jeung Ku Po was rich glutamic acid, lysine and aspartic acid. And especially, phenylalanine, which was rarely found in other green teas, was abundant in these green teas. The compositions of glutamic acid and methionine were increased as increasing the number of roasting process but those of aspartic acid and arginine decreased by these processing. The main fatty acids of Ku Jeung Ku Po green tea were linolenic acid, linoleic acid and palmitic acid and the contents of unsaturated fatty acid in green teas were composed over 70% of total fatty acid. And the fatty acid contents in green teas were not affected during Ku Jeung Ku Po's process. The contents of minerals in these teas was rich in the oder of potassuim. magnessuim and calciumim, and these contents were not observed the prominant change during the process.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2003년도 제10차 국제학술회의 및 추계정기 학술발표회
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• pp.34-35
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• 2003

Before making of tea, the number of leaf, plant height and node length in young shoot were 5.2, 14.9cm and 1,9cm respectively. These contents caused problems in leaf rolling and uniformity. No significant difference in quality and comoposition of roasted and steamed were observed, external shape and internal quality, however, were good from 1st to 3rd leaf. Chemical nutrition consists of leaf position, Total nitrogen content of terminal leaf was 4.88%, total free amino acid 21.12%, and caffein 3%. Vitamin C content was increased with increasing of leaf age. Making of roasted tea was required long time because camellia leaf was very hard and smoothly. Products had lower water color, perfume and taste. Internal quality of steamed tea was good in water color and taste. The contents of total nitrogen, total free amino acid, catechin, caffeine and vitamin C were 4.24%, 1.01, 17.7%, 2.6% and 75.7mg/ml.(중략)

• 한국식품영양과학회지
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• 제28권1호
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• pp.61-66
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• 1999

The purpose of this study was to improve the palatability of kochujang. The activities of liquefying amylase and saccharogenic amylase in Monacus anka koji were lower than those in Asp. oryzae koji. The acid protease activity(1.4 units/g) in M. anka koji was also lower than that(1.6 units/g) in Asp. oryzae koji. Glucosamine amount in Asp. oryzae koji was 1075 g, and that in M. anka koji was 318 g. Four kinds of Kochujang were prepared with Asp. oryzae koji(A), M. anka koji(M), mixed koji of Asp. oryzae and M. anka(A＋M), and mixture of M. anka koji and malt(M＋M). The pH of four kinds of kochujang was 5.1 in the beginning and was between 4.70~4.83 after 120 days of fermentation. Reducing sugar of kochujang was between 16.3~20.7% after fermentation and kochujang prepared with M＋M showed the highest reducing sugar content. Amino nitrogen of kochujang was between 182 mg%~230 mg% after fermentation and the highest amino nitrogen content was observed at kochujang prepared with A＋M. Kochujang prepared with M and M＋M showed higher a value than kochujang prepared with A and A＋M.