Amino-type Nitrogen Content Research Articles

Assessment of Bacillus subtilis SN7 as a starter culture for Cheonggukjang, a Korean traditional fermented soybean food, and its capability to control Bacillus cereus in Cheonggukjang

The aim of this study was to develop a bacteriocin-producing QPS (Qualified Presumption of Safety) status Bacillus strain as a starter culture for fermented soybean foods as well as food preservation with improved safety and organoleptic qualities. Strain SN7 isolated from Meju, a fermented soybean product of Korea, was selected based on antimicrobial activity against pathogens such as B. cereus and production of bacteriocin. The selected strain SN7 was identified as B. subtilis. Safety assessments of B. subtilis SN7 (hemolytic activity, virulence traits, and antibiotic resistance) indicated that B. subtilis SN7 does not present a risk to human health, and this new isolate can be confidently recommended as a safe starter culture for the food industry. Cheonggukjang, a traditional fermented soybean food of Korea, fermented using B. subtilis SN7 showed high amino-type nitrogen content with good sensory characteristics. As a controlling agent of B. cereus in culture medium and in a food model of Cheonggukjang, B. subtilis SN7 efficiently inhibited growth of B. cereus vegetative cells and inactivated germination of B. cereus spores. Furthermore, B. cereus was not detected in Cheonggukjang stored at 4 °C for 6 months. B. cereus was easily detected in fermented food during storage at low temperature, as endo-spores of B. cereus are resistant to various treatments such as heat treatment and can grow even at 4–5 °C. These results suggest that bacteriocin-producing B. subtilis SN7 has great potential as a controlling agent of B. cereus and as a starter culture in Cheonggukjang.

Functional beverage from fermented soymilk with improved amino nitrogen, β-glucosidase activity and aglycone content using Bacillus subtilis starter.

The bioactivity of soymilk was enhanced by fermentation with three strains of β-glucosidaseproducing Bacillus subtilis for 36 h at 37oC. The results indicated that protease, cellulase, and β-glucosidase activities were significantly (p<0.05) increased with increasing fermentation time. In addition, the amino-type nitrogen content in B. subtilis-fermented soymilk was increased to 121.1-140.7 mg% after 36 h of fermentation. Among the isoflavones in soymilk, the contents of β-glucosides or acetyl-glucosides were decreased, while aglycone content was increased by fermentation. In particular, the soymilk fermented with B. subtilis HJ18-9 had highest β-glucosidase activity and the largest increase in aglycone content. The total aerobic and anaerobic cell counts were increased with increasing fermentation time. Therefore, this study suggests that soy beverages fermented with β-glucosidase-producing B. subtilis have the potential to enhance the health and nutritional status of consumers.

Toxicological risk assessment of micro-organisms used as active substances in plant protection products

The aim of this study was to develop a bacteriocin-producing QPS (Qualified Presumption of Safety) status Bacillus strain as a starter culture for fermented soybean foods as well as food preservation with improved safety and organoleptic qualities. Strain SN7 isolated from Meju, a fermented soybean product of Korea, was selected based on antimicrobial activity against pathogens such as B. cereus and production of bacteriocin. The selected strain SN7 was identified as B. subtilis. Safety assessments of B. subtilis SN7 (hemolytic activity, virulence traits, and antibiotic resistance) indicated that B. subtilis SN7 does not present a risk to human health, and this new isolate can be confidently recommended as a safe starter culture for the food industry. Cheonggukjang, a traditional fermented soybean food of Korea, fermented using B. subtilis SN7 showed high amino-type nitrogen content with good sensory characteristics. As a controlling agent of B. cereus in culture medium and in a food model of Cheonggukjang, B. subtilis SN7 efficiently inhibited growth of B. cereus vegetative cells and inactivated germination of B. cereus spores. Furthermore, B. cereus was not detected in Cheonggukjang stored at 4 °C for 6 months. B. cereus was easily detected in fermented food during storage at low temperature, as endo-spores of B. cereus are resistant to various treatments such as heat treatment and can grow even at 4–5 °C. These results suggest that bacteriocin-producing B. subtilis SN7 has great potential as a controlling agent of B. cereus and as a starter culture in Cheonggukjang.

고구마를 이용한 고추장의 숙성 중 이화학적 특성 변화

Kochujang was prepared by replacement of rice (25%, control) with pumpkin or purple sweet potato by 0. 5, 10, and 15% (total addition ratio of rice and sweet potato=25% of sample). Effects of the addition of sweet potato on physiochemical properties of fermented Kochujang were investigated. Viable cells of yeast decreased in the sweet potato-added Kochujang at the later stage of fermentation, while there was no significant difference in the number of bacteria among the test groups. As the addition ratio sweet potato increased, α-amylase activity increased while protease activity decreased. Hunter L, a, and b values of Kochujang prepared with purple sweet potato were lower than those with pumpkin sweet potato. Changes in ΔE value was greater in Kochujang prepared with pumpkin sweet potato than that with purple sweet potato. Oxidation-reduction potential and water activity were higher in sweet potato-Kochujang than control, but reducing sugar content was higher in control. Alcohol and amino-type nitrogen contents were higher in Kochujang prepared with pumpkin sweet potato than that with purple sweet potato, but it was not significant. Overall sensory acceptability was highest in Kochujang prepared with 10% of purple sweet potato while that with 15% pumpkin sweet potato was the least preferred.

Increasing Protease Activities and Antioxidant Properties of Koji for Soy Sauce Brewing by Adding a Medicinal Herb Rhodiola rosea

Abstract Koji preparation is the key step in soy sauce brewing. In this study, 21 medicinal herbs were tested for their abilities in enhancing the protease activities of soy sauce koji. Among these herbs Rhodiola rosea was found to be the most efficient in increasing protease activities. Kinetic analyses revealed that R. rosea addition not only promoted microbe growth and increase the activities of neutral and acid proteases (by 29.8% and 13.4%, respectively) but also elevated α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity and total phenolics and flavonoids (by 9.5%, 47.1% and 14.1%, respectively); the formations of proteases and antioxidant properties depend largely on microbe growth; and the promotion effects of R. rosea addition were mainly displayed in later stage of fermentation. Using the R. rosea koji for soy sauce production resulted in 8.9%, 19.1%, 6.6%, 23% and 102% higher of total and amino-type nitrogen contents, protein utilization, total phenolics and flavonoids, respectively.

Bacillus subtilis 균주를 이용하여 제조한 팽화미 된장의 품질 특성

This study investigated the quality characteristics of popped rice Doenjang prepared with different Bacillus strains (Bacillus subtilis KACC 15935, and Bacillus subtilis HJ18-9). The changes in the enzyme activity (protease, cellulase, and ɑ-amylase), amino-type nitrogen and ammonia-type nitrogen contents, and the reducing sugar were investigated during the fermentation period. Enzymes such as protease, cellulase, and a-amylase plays an important role in the changes in composition of nutrients, and in flavor and taste of popped rice Doenjang. Protease activities of the popped rice deonjang fermented with different Bacillus strains (control, B. subtilis KACC 15935, and B. subtilis HJ18-9) was in the range of 171.77-185.97 unit/g at the beginning of fermentation, and there were no significant differences among the samples. On the other hand, the protease activity in popped rice Doenjang fermented with B. subtilis HJ18-9 increased significantly up to 248.77±4.53 unit/g at the end of fermentation (p&lt;0.05). Cellulase activity and a-amylase activity of popped rice Doenjang in HJ18-9 was higher than these of other samples. After 56 days of fermentation, amino-type nitrogen in popped rice deonjang fermented with control, B. subtilis KACC 15935, and B. subtilis HJ18-9 increased significantly up to 174.99±3.70, 166.59±1.40, 225.39±3.70 mg％, respectively (p&lt;0.05). These results suggested that B. subtilis HJ18-9 was a suitable starter for the preparation of soybean paste.

우즈베키스탄 고려인 제조 장류의 품질특성

Many Koreans, who are resident in Uzbekistan and Central Asia, are still avid fans of the Korean traditional soybean paste. No research study has been conducted on the Korean-Uzbekistanis soybean paste. The purpose of this study was to investigate the quality characteristics of the Korean-Uzbekistanis fermented soybean paste. Nine kinds of soybean pastes prepared by Korean-Uzbekistanis were collected, and their physiochemical properties (protease activity, amylase activity, amino type nitrogen content, reducing-sugar contents, and aerobic bacterial count) have been analyzed. The Korean-Uzbekistanis’ fermented soybean paste (KU-SP) showed higher protease activity than the Korean fermented soybean paste (K-SP). The protease activities of KU-SP B, D, and H were 832, 807 and 630 unit/g, respectively, which were significantly different from others. In addition, the content of amino-type nitrogen in KU-SP B, D, and H were 777 mg%, 686 mg%, and 705 mg%, respectively. In the meanwhile, α-amylase activities showed wide ranges starting from 10.82 to 47.98 unit/g. The KU-SP values, except for the KU-SP C, have shown higher activities than the K-SP. The reduced sugar content and totoal aerobic bacteria number were within the range of 0.55~3.43%/g and 7.24~8.79 log CFU/g, respectively. Finally, this research provided the basic data and information for the quality characteristics of commercial soybean paste prepared by the Korean-Uzbekistanis. These basic data can be useful for understanding the Korean food culture in Central Asia.

Effect of the Addition of Antimicrobial Materials Before and After Aging on the Physicochemical Properties of Low-Salt Kochujang during Storage

To improve the shelf life of low-salt Kochujang, Korean hot pepper paste, antimicrobial materials were added at different times before and after aging. The kochujang was then packaged and stored at 30oC for 15 weeks, and changes in microbiological and physiochemical properties were evaluated. Hunter a- and bvalues decreased considerably during storage. The total color difference (△E) was greater in the ethanol-chitosan (EC) treatment than in the control and after pasteurization (A-P) treatment. Gas was produced until the seventh week of storage. The control and the A-P treatments produced more gas than the other treatments, and these had the largest number of yeasts and aerobic bacteria. The pH of the EC treatment was higher than that of the other treatments, and the A-P treatment had the highest level of titratable acidity. During storage, the oxidation-reduction potential was lower in the EC and ethanol-mustard-chitosan (EMC) treatments. The reducing sugar content decreased remarkably in the control and A-P treatments, with high production of ethanol. There was a significant change in the content of amino-type nitrogen in the control and A-P treatments, and the content of ammonia-type nitrogen was lowest in the EMC treatment. In the sensory test of kochujang, the ethanol-mustard (EM) and ethanol (E) treatments were significantly higher than the EC, control, and A-P treatments (p <0.05). EM or E alone was effective in extending the shelf life of kochujang when added before aging.

다시마 추출물을 첨가한 보리된장의 일반적 특성과 항산화 효과

다시마에는 항산화성과 무기질이 풍부하고 알긴산 등 증점 다당류가 풍부한 해조류이다. 다시마 추출물 함량을 달리한 재래식 보리된장을 제조하여 2개월간 발효시키면서 항산화능 및 이화학적 실험을 실시하였다. 제조된 된장의 pH는 5.80∼6.86, 산도는 0.57∼1.87%, 수분 함량은 65.30∼40.90% 범위로 저장기간 동안 pH는 감소하였고 산도는 증가하였다. 점도는 보리된장 대조군이 4,913 cps이었고 다시마 추출물의 함량이 증가할수록 4,793∼9,333.3 cps까지 비례하여 증가하였으며 저장기간에 따라 비례하였다(P＜0.05). 다시마를 첨가한 보리된장의 색도는 다시마 추출물의 첨가량에 따라 각각 L 값과 b 값은 증가하였으나 a 값은 다시마 추출물의 함량에 따라 감소하는 경향을 나타내었다. 총 페놀 함량은 대조군이 12.72 ㎎ TAE/g, 처리군이 13.40∼16.37 ㎎ TAE/g이었으며(P＜0.05), flavonoid 함량은 대조군이 0.98 ㎍ RE/g, 처리군이 1.25∼1.56 ㎍ RE/g으로 다시마 추출물의 첨가량과 비례하여 항산화능에 영향을 주었다(P＜0.05). DPPH 라디칼 소거능은 BHA를 (+)대조군으로 하여 IC50 함량을 각각 구하였으며 보리된장 대조군 23.23 ㎎/mL, 다시마 추출물 처리군의 경우 24.83 ㎎/mL, 10.28 ㎎/mL 수준으로 다시마 추출물이 된장의 항산화능을 증진시킨 것으로 나타났다. 다시마 추출물을 첨가한 보리된장의 총균수는 초기에 7.20∼7.57 ? CFU/g으로 나타났고 초기 젖산균수는 4.20∼4.71 ? CFU/g 범위로 나타나 다시마 처리군의 총균수는 대조군보다 적고 젖산균 수는 더 많은 것으로 나타났다. 관능검사에서 감칠맛은 대조군에 비해서 20% 다시마 처리군이 6.1점으로 유의적인 차이를 보였고(P＜0.05), 질감 또한 대조군(5.7점)보다 20% 다시마 추출물을 첨가한 군이 6.4점으로 유의적으로 높았으며(P＜0.05), 전체적 기호도는 대조군이 5.6점이었고 20% 첨가 처리군에서 6.5점으로 유의차가 크게 나타났다(P＜0.01). 이상의 결과에서 보리된장에 다시마 추출물을 첨가하면 항산화능도 뛰어나므로 보리된장의 제품화 가능성도 더욱 크다고 사료된다.

전통적인 방법으로 제조된 된장 제품의 이화학적 및 관능적 특성에 대한 연구

To study traditional Doenjang characteristics, Doenjang was purchased from five different provinces: Chungcheong (CC), Gangwon (GW), Gyeonggi (GG), Gyeongsang (GS), and Jeolla (JL). To determine physicochemical characteristics, contents of reducing sugar, amino type nitrogen, salt, pH, and acidity were analyzed. The sensory characteristics were analyzed by sensory descriptive analysis. Reducing sugar content was highest for Doenjang from GW province. Amino type nitrogen content was highest for Doenjang from JL province. The salt content was highest in Doenjang from CC and GS provinces. After principal component analysis (PCA) based on sensory descriptive analysis, salty taste and aftertaste were highly correlated with overall acceptance. In the correlation analysis among chemical compounds and overall acceptance, Doenjang contained low reducing sugar content, and high pH value was positively correlated with overall acceptance. In conclusion, Doenjang with high pH value and salty taste and aftertaste have high overall acceptance.

Bacillus subtilis MC31와 Lactobacillus sakei 383의 혼합배양으로 향상된 풍미와 GABA 함량을 지닌 청국장의 품질 특성

Chungkookjang has several functional properties, such as fibrinolytic activity, anticancer effects, and antioxidant effects. However, children do not like Chungkookjang because of its foul odor. A mixed culture of Bacillus subtilis MC31 and Lactobacillus sakei 383 was used to improve the production of GABA in Chungkookjang and its flavor. Most of the foul odor of Chungkookjang was removed. The slime content and viscosity of Chungkookjang fermented in the mixed culture were similar to those of commercial Chungkookjang when B. subtilis MC31 and Lactobacillus sakei 383 were inoculated in a 1:1 ratio. The maximum GABA content was obtained when Chungkookjang was fermented with B. subtilis MC31 and L. sakei 383, which was fermented at 37℃ for 72 hr. During the period of fermentation, the viable cell number of B. subtilis MC31 reached a peak (log 9.13 CFU/g) at six days, and L. sakei 383 reached a peak (log 6.78 CFU/g) at two days. The moisture, crude ash, crude protein, crude fat, and crude fiber contents were 61.71%, 2.05%, 17.54%, 8.36%, and 1.95%, respectively. The amino-type nitrogen content of Chungkookjang fermented by B. subtilis MC31 and L. sakei 383 was less than Chungkookjang fermented by B. subtilis MC31 alone. The ammonia-type nitrogen and reducing sugar content of the Chungkookjang fermented by B. subtilis MC31 and L. sakei 383 were higher than that of steamed soybean. The glutamic acid and GABA content detected with an amino acid analyzer were 1.40 ㎎/g and 0.47 ㎎/g, respectively. These results suggest that fermentation with B. subtilis MC31 and L. sakei 383 in a 1:1 ratio removes more of the foul odor and increases the GABA content compared with single fermentation.

저염 마늘된장의 숙성기간에 따른 품질특성

We investigated the changes in the quality characteristics of Doenjang with low salt contents (6, 8, 10, and 12%) and 10% garlic. The Doenjang was analyzed at an interval of a week during its fermentation for six weeks, at room temperature. Its L color gradually decreased, but its a and b colors did not change significantly. Its salinity increased by about 1% after six weeks. In contrast, immediately after its preparation, its pH was gradually decreased and its acidity was increased for the fermentation. The reducing sugar was significantly increased from 1.34~1.88 g/100 g immediately after its preparation to 7.25~9.13 g/100 g after six weeks, which was higher as the salt concentration decreased. The amino-type nitrogen doubled from 100~130 mg% at 0 week to 210~290 mg% at six weeks, which were lower with the higher salt concentrations. The growth curve of the Bacillus fermentation strains of Doenjang increased to two weeks but gradually decreased since, and the growth of the Bacillus was favorable for up to two weeks in the Doenjang with 10% and 12% salt added. Otherwise, the yeast was reduced rapidly during the early fermentation of the Doenjang, and slightly changed after three weeks of fermentation. The results of this study showed that the reducing sugar and amino-type nitrogen contents of the low-salt garlic Doenjang were higher with the lower salt dose, and the physicochemical quality of the 6%-salt Doenjang was not significantly affected. Thus, we suggest that low-salt Doenjang can be manufactured with the addition of 6% salt and 10% garlic.

마늘 첨가 된장의 숙성 중 품질특성 변화

마늘을 0, 10, 20 및 30% 첨가하여 된장을 제조한 후 6주간 숙성시키면서 1주 간격으로 된장의 품질 관련인자의 변화를 분석하였다. 명도는 마늘 농도와는 상관없이 모든 시료가 숙성기간이 길어짐에 따라 그 값이 감소하였으며, 마늘 첨가 농도가 높아질수록 더 낮았다. 황색도는 숙성 후기에 그 값이 감소하였는데, 대조군보다 마늘 첨가된장에서 더 낮았다. 제조 직후와 비교하여 숙성 1주차에 pH는 크게 감소하고 산도는 증가하였으나 그 이후로는 불규칙한 증감을 보였으며, 마늘의 첨가 농도에 따른 통계적인 유의차도 없었다. 아미노태 질소는 숙성 5주차까지 지속적으로 증가하는 경향을 나타내었는데, 숙성 5주차와 6주에는 시료군간에 유의적인 차이가 없어 마늘의 첨가가 된장의 아미노태 질소 함량에 큰 영향을 미치지 않음을 확인할 수 있었다. 환원당 역시 숙성기간이 길어짐에 따라 그 함량 역시 증가하였는데, 제조 직후에 비하여 숙성 6주 뒤에는 모든 시료군에서 약 2.5배 증가하였다. 이소플라본 함량은 숙성시간의 경과와 더불어 감소하는 경향을 보였으며 숙성 초기에는 배당체 형태의 함량이 높았으나 후기로 갈수록 그 함량은 감소하고 비배당체 형태는 증가하는 경향이었다. Bacillus는 마늘의 첨가량에 따른 차이가 없었으나 효모수는 마늘의 첨가량이 높을수록 적었다. In this study, we investigated the quality characteristics of Korean soybean paste, Doenjang, fermented for 6 weeks at room temperature with the addition of 0, 10, 20 and 30% garlic. Samples were analyzed in one-week intervals. The lightness decreased in all samples as the fermentation period and garlic concentration increased. Yellow index decreased in weeks 5~6 compared with weeks 0-1, for which the values were lower for the garlic-added Doenjang than the control. The pH increased, greatly reducung the acidity in week 1 compared with week 0. Significant differences in the pH and acidity were not observed among the sample groups. Amino type nitrogen contents increased continuously up to weeks 5, displaying no significant differences among the sample groups at weeks 5 and 6. In addition, reduction in the sugar content increased depending on the fermentation period. It increased in all sample groups by about 2.5 times after 6 weeks compared with the initial levels. Isoflavone content was also reduced generally depending on the fermentation period. In the early fermentation periods, the aglycone contents were the higher than the glycosides, while the glycoside contents increased over the fermentation period. The presence of Bacillus was not significantly different among the garlic added groups, but yeast was lower in the Doenjang with high garlic content.

전통 된장의 숙성 기간에 따른 감각·화학적 품질특성

In order to characterize the quality of Doenjang, fermented Korean soybean paste, subjected to long-term aging, this study performed physico-chemical analyses and sensory evaluation according to aging period (from 1 to 9 years). Regarding the proximate composition of Doenjang according to aging period, moisture, crude protein, crude lipid, crude ash, and salt contents showed little differences among Doenjang samples. Amino-type nitrogen content was 1,046.7 mg% in the 1 year-aged sample, 990.9~996.9 mg% in the 2~5 year-aged samples, and 1,214.1~1,304.8 mg% in the samples fermented more than 5 years. ΔE value, reflecting total color differences between the samples, increased according to aging period. Ratios of linoleic and linolenic acids, which are essential fatty acids in soybeans, constituted 55% of total fatty acids, which was the most abundant among all fatty acids. The major free sugar in Doenjang was fructose at a content of 1.6~2.2% in 1~9 year-aged Doenjang. Glycoside form of isoflavones in Meju constituted 77.1%, and the aglycon form constituted 22.9%. However, the glycoside type of isoflavones in soybeans was converted to aglycon type in Doenjang through fermentation and aging. In the sensory evaluation of Doenjang samples, brown color, salt smell, soy sauce flavor, and viscosity all increased according to aging period, whereas sweet flavor, roast smell, beany flavor, salty taste, and acrid taste showed no significant differences. In cluster analysis of the sensory attributes of Doenjang according to aging period, 1 year-aged Doenjang was significantly different between 2 year- and 3~5 year-aged Doenjang.

전통장류 유래 Bacillus sp.를 이용한 콩 발효물의 품질 특성

전통 장류 유래 효소 활성 및 항균 활성 우수 Bacillus sp.를 스타터로 한 콩 발효물의 품질 특성을 분석하였다. 총균수는 HJ5-2를 접종한 시료가 3.00×109 CFU/mL로 가장 높았으며, 유산균은 스타터 첨가 콩 발효물에서 2.50×102~7.30×104 CFU/mL를 나타나는 것으로 보아 접종된 균주가 우점종이 된 것을 확인하였다. α-Amylase 활성은 RD7-7(20.82 unit/mL)과 HJ18-4(18.45 unit/mL), protease 활성은 RD7-7(647.92 unit/mL)을 접종한 콩 발효물이 높은 활성을 나타내었다. 환원당 함량은 HJ18-4(2.35%), 아미노태 질소 함량은 RD7-7(227.96 mg%) 접종 콩 발효물에서 높은 함량을 나타내었다. 아미노산 함량은 glutamic acid, aspartic acid, leucine, lysine, arginine 순으로 검출되었다. 유기산은 oxalic acid(36.51~63.57 mg/100 g)가 모든 실험군에서 검출되었으며, succinic acid(600.15~429.49 mg/100 g)는 control과 RD7-7 접종 콩 발효물에서 검출되었다. 향기 성분을 분석한 결과 총 28종(esters 3종, ketones 6종, aldehydes 2종, alcohols 4종, hydrocarbons 2종, pyrazines 2종, acids 4종, 기타 4종)이 검출되었으며, RD7-7과 HJ18-4를 접종한 콩 발효물에서 23종의 향기 성분이 검출되었다. 본 연구는 고품질 장류용 스타터 개발을 위한 단일균 접종 콩 적용 시험으로 향후 혼합배양 스타터개발 및 기능성 콩 발효소재 개발을 위한 기초자료로 제시하고자 한다.

Bacillus subtilis HJ18-3과 KACC 15935를 이용하여 제조한 청국장의 품질특성과 isoflavone 함량의 변화

This study was conducted in order to investigate the change of isoflavone composition (glycoside and bio-active aglycone), and to evaluate the quality characteristics of Cheonggukjang, which was prepared by different bacillus strains. After the 48-hour fermentation, the contents of daidzein, genistein, and glycitein in the Bacillus subtilis HJ18-3 have significantly increased up to approximately 89.06±3.59, 10.36±0.28, and 101.37±3.67 ug/g, respectively. The contents of daidzein, genistein, and glycitein in the Bacillus subtilis KACC 15935 were 38.88±5.39, 12.58±2.14, and 80.13±0.71 ug/g, respectively. The original content of daidzein was 3.96 ug/g, while genistein and glycitein were not measured. However, the contents of daidzen and genistein in HJ18-3 and in KACC 15935 were decreased. The α-Amylase and cellulase activities of Chungkookjang in HJ18-3 were higher than in the KACC 15935. The contents of Chungkookjang in HJ18-3 were 29.70±11.66 and 4861.3±388.07 unit/g, respectively. The amino type nitrogen contents and ammonia type nitrogen contents of Chungkookjang in KACC 15935 were higher than in the HJ18-3. These results suggested that it could be used to increase the bioactivity via fermentation with the Bacillus subtilis possessing a β-glucosidase activity with a view towards the development of functional foods.

죽염 된장의 발효 특성 및 기능성 증진 효과

The aim of this study is carried out to evaluate the fermentation characteristics and increased functionality when doenjang was prepared with bamboo salts. Grain type mejus were fermented with mixed starter cultures of Aspergillus oryzae, Bacillus subtilis, and Lactococcus lactis. These mejus were mixed with different kinds of saltspurified salt (PD), sea salt (SD), one-time baked bamboo salt (1×BD), three-time baked bamboo salt (3×BD), and nine-time baked bamboo salt (9×BD)－ when doenjangs were prepared. For doenjang fermentation period of 8 weeks at 37°C, the fermentation characteristics of all the groups were compared. The amino type nitrogen content and enzyme activities (protease and α-amylase) in the samples were significantly increased. In DPPH radical scavenging activities and hydroxyl radical scavenging activities, 9×BD (47% and 69%) showed the highest scavenging activities compared to PD (40% and 49%), SD (42% and 57%), 1×BD (42% and 64%) and 3×BD (45% and 65%) (P<0.05). The anticancer effects of doenjang in HT-29 cancer cells indicated all the groups, especially doenjang prepared with bamboo salts were higher than the others (P<0.05). Apoptosis related genes of Bax and Bcl-2, as well as inflammation related genes of iNOS and COX-2 were regulated by the treatment of doenjangs in HT-29 cancer cells. SD, 1×BD, 3×BD, and 9×BD increased the expression level of Bax and decreased the expression level of Bcl-2, iNOS, and COX-2. These results suggest that sea salt and bamboo salt especially bamboo salt could improve fermentation characteristics and functionality of doenjang and play an important role in regulating apoptosis and inflammation related genes in cancer cells.

메밀 속성 장 프리믹스 제조 및 품질특성

Abstract 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 (688.76 ㎎%) 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 ㎏), the coliform of the 2.5 ㎏ sample decreased faster than that of 1.25 ㎏ 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.Key words: Buckwheat Soksungjang, premix, fermentation, physiochemical characteristics

중국 내 시판 한식 장류의 품질특성

Sun Young Lee, Soo Hwa Baik, Yu Jin Ahn, Jin Song, Jae Hyun Kim, and Hye Sun Choi*Department of Agro-food Resources, National Academy of Agricultural Science, RDAAbstract Soybean-based fermented foods have been used as traditional condiments in Korea, Japan and China. ThirteenKorean types of soybean sauce that had been manufactured and sold in China were examined to evaluate their quality.The pH, salinity, and moisture content of the samples were pH 5.17-6.86, 8.0%-23.0%, and 46.446-70.40%, respectively.The amino-type nitrogen content was in the range of 199.18 to 736.46 mg%. The total aerobic bacterial counts were 4.83-7.89 Log CFU/g. The coliform count of gochujang (CNH-2) was 2.31 Log CFU/g, but none were detected in the othersamples. Moreover, Bacillus cereus counts from samples of doenjang and gochujang were in the range 2.00-4.09 LogCFU/g. The protease and amylase activity of samples were 379.02-781.36 unit/g and 5.29-63.27 unit/g, respectively.Keywords: China, fermented soybean paste, quality characteristics, fermentation

Quality characteristics of Cheonggukjang containing Phellinus linteus extracts and antitumor effects in hep-2 and SK-MES cells

The quality characteristics of cheonggukjang containing Phellinus linteus extracts (PLE) and its cytotoxicity in Hep-2 and SK-MS-cells were investigated. Cheonggukjang containing 0.3% PLE showed the highest protease activity (7th aging day). The reducing sugar content and the amylase activity of cheonggukjang supplemented with 0.3% PLE increased immediately on the 1st aging day, and decreased slightly until the 15th aging day. All samples showed an increase in the amino-type nitrogen content. The dominant volatile compound detected using chromatography-mass spectrophotometry was 2,5-dimethyl pyrazine with the highest peak area value of 17.36% observed in cheonggukjang containing 0.3% PLE (3rd aging day). Cheonggukjang containing 0.3% PLE exhibited the best taste and acceptability with the least unpleasant odor. Cheonggukjang supplemented with PLE had a higher antitumor activity against SK-MES-1 and Hep-2 cells than a control. Hep-2 cells treated with a 10 mg/mL extract of cheonggukjang containing 0.3% PLE showed the highest growth inhibition rate of 84.74%.