The objective of this study was to evaluate the effects of low temperature-adapted Saccharomyces cerevisiae Y297 and fermentation temperatures on the quality of Yakju brewed. Physicochemical properties of Yakju brewed were compared pH, total acidity, ethanol, free amino acid, organic acid contents, and volatile flavor compounds in S. cerevisiae Y297 with control treatment. Cooked non-glutinous rice and saccharogenic amylase in koji were mixed with ethanol-producing yeasts and then fermented at 15℃, 20℃, and 25℃ for 20 days. Yakju brewed using the Y297 treatment showed the highest ethanol yield (17.9%) at 20℃. Expression of heat shock protein (HSP) 104 was evaluated by immunoblotting as an indication of adaptation to low temperatures (15℃); levels of the HSP104 protein were higher in the Y297 treatment than in the control. Organic acid analysis showed that the lactic acid content of Yakju brewed using the control was the highest at 25℃. Finally, free amino acid analysis showed that the Y297 treatment had a higher proportion of essential amino acids than the control. Overall, these results indicate that S. cerevisiae Y297 could be used as a suitable yeast for Yakju brewed under low temperature (15℃) condition.

Bacillus amyloliquefaciens CGD3 was used as a starter for fermentation of amaranth and cultural characteristics and biological activities of amaranth were investigated. The viable cells in fermented amaranth was 4.54~8.01 log CFU/mL during 96 hr of fermentation period. Protease activities of amaranth showed the highest by 36.7 unit/mL after 72 hr of fermentation. The total phenolic and flavonoid contents of amaranth increased with fermentation time while its total sugar content decreased. The total protein content was the highest in amaranth fermented for 96 hr (0.25 mg/g). The DPPH scavenging activities, FRAP (ferric reducing antioxidant power), and reducing power of amaranth were highest in amaranth fermented for 72 hr, showing 84.46%, 551.91 μM, and 2.74, respectively. ACE (angiotensin converting enzyme) and α-Glucosidase inhibition rates increased with fermentation time and showed the highest after 72 hr.

This study was conducted to investigate the effects of different carbon sources on the anaerobic fermentation characteristics in the startup phase using the biochemical methane potential test. The treatments for this experiment were combinations of carbon sources (starch, cellulose, and xylan). Anaerobic fermentation was done at 37oC for 18 days with agitation and pH, ammonia nitrogen, volatile solids reduction, gas production, methane content, and methane production were investigated at 0, 1, 2, 3, 4, 5, 7, 9, 12, 15, and 18 days after incubation in triplicate. In the experiment, the pH was changed depending on the characteristics of the carbon source. The ammonia nitrogen concentration was the highest in the starch-treated group at 7, 12, and 15 days after incubation (P < 0.05). Cumulative volatile solids reduction was the highest in the cellulose-treated group at 18 day after incubation (P < 0.05) and cumulative gas production was higher in the cellulose-treated group than for other two treatments at 18 day after incubation (P < 0.05). Methane content was the lowest in the xylan-treated group at 18 days after incubation (P < 0.05). Cumulative methane production was higher in the xylan-and cellulose-treated group than in the starch-treated group at 18 days after incubation (P < 0.05). In this study, the carbon sources had significant effects on anaerobic fermentation characteristics; especially, the carbon source was shown to have a positive effect on the operation time and hydraulic retention time for the anaerobic digestion startup phage. Therefore, carbon sources should be considered systematically for efficient anaerobic digestion of organic waste.

This study was designed to improve the sensory characteristics and mitigate the bitter taste of Platycodon gradiflorum. It was aimed at investigating the qualitative properties of fermented P. gradiflorum after repeated steaming and drying treatments. P. gradiflorum was heated for 2 hr at 95℃, being the first and third treatments compared afterwards. Lactobacillus plantarum, at a concentration of 10%, was used as starter culture. As a result, the third steaming process and the addition of starter improved the physical and chemical properties of P. gradiflorum i.e., crude saponin and total polyphenol contents increased significantly. Moreover, P. gradiflorum steamed three times and fermented by L. plantarum showed the higher overall preference score. Our results indicated that the three-time steaming and drying was an effective manufacturing process for the production of high-quality fermented P. gradiflorum. Lactic acid-fermented P. gradiflorum also could have a potential use as a valuable resource for the development of functional products.

본 연구에서는 와인제조에 있어 향미 증진과 같은 품질 향상에 도움이 된다고 알려진Pichia anomala JK04와 일반 적으로 와인 양조에 주로 이용되고 있는 Saccharomyces cerevisiae Fermivin을 혼합 발효하여 감와인의 발효 특성을 비교하였다. 감와인의 발효특성 결과 발효 종료 시 대부분 의 실험구에서 pH 4.0~4.2, 총산 0.5~0.6%를 나타내었다. 당도와 환원당 함량 변화는 발효가 진행될수록 점차 감소하 여 S. cerevisiae Fermivin 단독 발효구와 P. anomala JK04 혼합 첨가 발효구에서 발효 종료시점에서 대부분의 당이 소비되었다. 최종 알코올 함량은S. cerevisiae Fermivin 단독 발효구와S. cerevisiae Fermivin과P. anomala JK04의 혼합 첨가 발효구에서 알코올 생성이 빨랐으며 발효 종료 시 모든 구의 알코올 농도는 12~13%를 나타내었다. 각 첨가구 의 총 페놀성 화합물 함량은 0.05 mg/mL 로 초기 페놀성 화합물 함량과 비슷한 수준을 유지하였다. 감와인의 hue value는 발효 초기에 비해 증가하여 4~5의 값을 나타내었 고, intensity value는 발효초기 0.5의 값에서 점차 감소하여 발효 종료 시까지 0.1~0.2의 값을 유지하였으며 휘발성 향 기성분의 경우 P. anomala JK04의 첨가 비율이 높을수록 S. cerevisiae Fermivin 단독발효구 보다 다양한 알코올류, 에스테르류가 생성되었다. 관능검사 결과에서 향기와 맛의 평가에서P. anomala JK04를 첨가한 모든 혼합 발효구에서 S. cerevisiae Fermivin 단독발효구 보다 높은 점수를 얻었다.

꾸지뽕 열매의 부가가치를 증대하기 위해 꾸지뽕 발효식 초를 제조하고 그의 발효조건을 확립하였다. 전통발효식품 으로부터 초산내성, 초산 고생산능, ethanol 내성 및 아황산 내성이 우수한 49종의 초산 균주를 분리하였고, 16S rRNA 유전자 염기서열의 해독 결과, Acetobacter indonesiensis, A. cerevisiae, A. orientalis, A. tropicalis, A. fabarum, A. pasteurianus 및 A. syzygii으로 동정되었다. 이들 중 GRAS 균주인 A. pasteurianus SCMA5와 SCMA6를 발효 균주로 최종 선정하였다. 최적 발효는 꾸지뽕 열매 함량이 40%(v/v)인 즙액과 5%(v/v) ethanol을 첨가하여 25℃에서 72시간 발효가 가장 적절하였다. 관능평가 결과, SCMA06 균주를 적용한 발효액의 선호도가 SCMA05 균주를 적용한 발효액보다 높았다. SCMA06 균주를 사용한 발효식초에서 항산화 능력을 측정하는 DPPH 라디컬 소거활성의 경우 대조구에 비해 53.02±0.78%이상 높게 나타났고, 항당뇨 능력을 측정하는 AGI활성은 발효 72시간에 91.40±2.43% 저해능을 보여 시판중인 acarbose보다 활성이 높았다. 이번 연구는 꾸지뽕 열매를 활용한 발효식초 제조를 위한 산업화 연구에 기여할 수 있을 것이다.

정상수확 후지와 늦수확 후지 사과를 속성 발효 효모인 S. cerevisiae SS89로 발효하면서 발효 특성을 조사하는 한편 사과주의 이화학적 특성을 조사하였다. 정상수확 및 늦수확 후지사과의 가용성 고형분 함량은 각각 13.0, 13.6˚Brix로서 늦수확 후지 사과가 다소 높았으나 총산의 함량과 경도는 낮게 나타났으나 유의적인 차이는 없었다. 사과주의 발효 중 pH와 총산 함량의 변화는 거의 유사하였으나 가용성 고형분의 감소, 알코올 함량 및 효모 생균수의 증가에 있어서 늦수확 사과의 경우가 빠르게 나타났다. 그러나 발효 말기 잔존 가용성 고형분 함량과 최종 알코올의 농도는 수확기와 무관하게 유사한 수준을 나타내었다. 늦수확 사과주의 경우 정상수확 사과주보다 다소 낮기는 하였으나 총 페놀성 화합물의 함량이 1.27 mg/mL, DPPH 라디칼 소거능이 89.5%로서 높게 나타났다. 또한 malic acid 함량과 hue 값, 명도 및 황색도 등이 다소 높았으나 아세트알데히드, 에틸아세테이트, 고급알코올의 함량 등은 매우 유사한 수준으로 나타났다. 관능평가 결과 늦수확 사과주는 향에 있어서는 유사한 값을, 색에 있어서는 낮은 점수를 받았으며 맛에 있어서 정상수확 사과주보다 높은 점수를 얻었으나 유의적인 차이는 없었다.

전통발효식품으로부터 분리한 발효능이 우수한 미생물과 기능성이 밝혀진 농특산 향토자원을 활용한 새로운 기능성 장류를 개발하고자 하였다. 꾸지뽕 열매를 A. oryzae koji, Lactobacillus 6종 및 Bacillus 2종에 대하여 발효시킨 결과, B. licheniformis SCDB 1234 균주가 kaempferol 함량을 9.54μg/g에서 217.04μg/g을 약 22배 증강시켜 최종 발효균주로 선발되었다. 꾸지뽕 열매를 선발균주를 활용하여 발효한 발효물 20배 희석액의 DPPH 항산화 활성은 대조구인 BHA, BHT의 92~99 ppm 농도와 유사한 활성을 보였고, tyrosinase 저해 활성도 arbutin이나 kojic acid의 95 ppm과 90 ppm과 같은 높은 저해 활성을 보였다. 꾸지뽕 열매 발효물을 첨가한 된장을 개발하여 유기산, 유리당 및 유리 아미노산을 분석하였다. 전반적으로 꾸지뽕 열매 발효물을 첨가하지 않은 장류와 유의적인 차이점을 보이진 않았다. 꾸지뽕 열매 발효물과 개발한 된장의 pancreatic lipase 저해활성을 측정하였다. 발효물의 경우에는 발효전보다 발효후에 더 높은 80% 이상의 높은 저해능을 보여주었다. 개발한 된장은 숙성전 된장이 숙성후 된장에 비해 더 높은 저해능을 보여주었다. 항당뇨 효과로 AGI활성을 분석한 결과, 꾸지뽕 열매는 발효전보다 발효후에 활성이 높게 측정되었고, 꾸지뽕 열매 발효액 10%를 첨가한 숙성전 된장의 AGI활성은 84.89±0.08%, 숙성후 된장은 91.25±0.04%를 나타내었다. 결론적으로 꾸지뽕 열매의 발효물의 생리활성 및 항산화 활성은 발효를 통하여 상승함을 보여주었고, 새로운 건강기능성 식품 개발에 활용가능성이 높은 잠재적 소재임을 보여준다.

분쇄한 생마늘 10%와 식염을 6, 8, 10 및 12%로 달리하여 저염 마늘 된장을 제조하고, 상온에서 6주간 숙성시키면서 일주일 간격으로 시료를 취하여 숙성기간에 따른 품질 특성의 변화를 분석하였다. 숙성 시간이 경과할수록 명도는 감소하였으나, 적색도와 황색도는 유의적인 변화의 경향이 없었다. 염도는 된장 제조 직후에 비해 숙성 6주차에 1% 정도씩 증가하였으며, pH는 저장기간이 경과할수록 점차 감소하였으며, 산도는 이와 상반되게 증가되는 경향이었다. 환원당은 숙성기간의 경과와 더불어 유의적으로 증가하여 된장 제조 직후에 1.34~1.88 g/100 g이던 것이 숙성 6주차에는 7.25~9.13 g/100 g으로 변화하였는데, 식염의 첨가 농도가 낮을수록 환원당의 함량이 더 높았다. 아미노태 질소는 100~130 mg%에서 숙성 6주차에는 210~290 mg%로 약 2배 증가하였는데, 식염의 첨가 농도가 높을수록 아미노태질소의 함량은 더 낮았다. 된장의 발효 균주인 Bacillus 균주의 생육은 숙성 14일까지 증가되다가 그 이후부터는 감소되는 경향이었는데, 식염 10%와 12% 첨가군에서는 숙성 14일까지 Bacillus 균주의 생육이 양호하였다. 반면 효모는 된장의 숙성 초기에 급격히 감소하였으며, 숙성 21일 이후에는 일정범위를 유지하여 큰 변화는 없었다. 이상의 결과를 종합하여 볼 때 마늘이 첨가된 저염 된장은 염농도가 낮을수록 환원당이나 아미노태 질소의 함량이 더 높았고, 이화학적인 품질에도 크게 영향을 받지 않아 6% 정도의 식염첨가로 저염화가 가능할 것으로 확인되었다.

The indigenous Saccharomyces cerevisiae strains S13 and D8 were isolated at the microbial succession stage during spontaneous fermentation of Campbell Early wine as a resistant to potassium metabisulfite and a high sugar concentration. In this study, the fermentation characteristics of Campbell Early wine were investigated and compared with those of S. cerevisiae W-3, an industrial wine yeast. Alcohol production by the two strains was delayed at the initial fermentation stage, but increased fast when the fermentation continued. After the fermentation, the S13 and D8 wines contained 12.6% and 13.2% (v/v) alcohol, respectively, which were significantly higher than the alcohol content of the W-3 wine (12%, v/v). No marked differences were observed in the residual soluble solid content and the pH. However, the S13 and D8 wines showed high levels of total acid content, including malic and lactic acids. Especially, the lactic acid content was 8.9-fold in the S13 wine and six-fold in the D8 wine, compared with that of the W-3 wine. The two strains produced a higher level of acetaldehyde and a lower amount of methanol in the wine than the W-3 strain. The iso-Butanol content was lower in the two indigenous yeast wines with similar levels of n-propanol and iso-amyl alcohol contents than that in the W-3 wine. In the sensory evaluation, the S13 and D8 wines had higher scores for their color, flavor, taste and overall preferences than the W-3 wine. Especially, the S13 and D8 wines had much higher scores than the W-3 wine for flavor and color, respectively.

We investigated the quality characteristics of brewing brown rice vinegar through a traditional static fermentation process. Accordingly, we decided to compare the physicochemical characteristics of brewing vinegar at different temperatures and filtration methods. In four to five weeks’ time, the acetic acid fermentation exhibited the highest titratable acidity and then it eventually decreased. The titratable acidity was affected by the filtration method. It was revealed that the titratable acidity was higher in the forced filtration than the traditional filtration method. Various organic acids were detected in order to initialize the fermentation stage and as the fermentation progressed, only the acetic acid could be detected. The total free amino acid content was higher at a temperature of 30℃ than at 20℃. Moreover, the free amino acid content was dependent on the acetate content during the acetic fermentation process. The main bioactive substance of the γ-aminobutyric acid content was more than twice at a fermentation temperature of 30℃ compared to the fermentation temperature of 20℃. Furthermore, the total amino acid and essential amino acid content at a temperature of 30℃ was excellent. The quality of the brown rice vinegar via forced filtration method at a temperature of 30℃ was the most excellent. Based on these results, the fermentation temperature and the use of nuruks (fermenting agent) affected the quality of the brown rice vinegar, and an appropriate method to consider its purpose is required.

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℃. Protease activity was the highest in black soybean Chungkookjang. α-amylase activity increased significantly up to 6 h of fermentation at 30℃and 40℃and then maintained constantly. It also increased up to 30-36 h of fermentation at 45℃and then decreased. β -amylase activity was the highest in black soybean Chungkookjang at 35℃and 40℃and in yellow soybean Chungkookjang at 45℃. Production pattern of reducing sugar was similar to that of β-amylase. Amino-type nitrogen, viable cell number and reducing sugar content and β-amylase activity was the highest in Chungkookjang fermented at 40℃. 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.

This study was performed to improve quality of traditional Yakju and compares quality of Yakju according to different rice cultivars. The pHs of Ilmi Yakju and Hanarum Yakju showed 4.14 and 4.07, respectively and the other Yakju's pHs were ranged from 3.92 to 3.98. The content of total acid of Yakju using Indica rice imported from Thailand was the highest among the samples. The major components of free sugar was glucose and the highest content of total free sugars was found in Indica Yakju. The content of reducing sugars in Yakju using Indica rice was the higher than other samples. The ethanol content of Hanarum Yakju showed higher than those Yakju's and the lowest ethanol content found for the indica Yakju. The volatile compounds from the rice Yakju were identified by GC-MS. Twenty-one volatile compounds were found in rice Yakju. And the major volatile compounds were ethanol, acetic acid, 1-methyl-1-propanol, 2-methyl-butane, 3-methyl-1-butanol, iso-amylalcohol and 1-hexanol from Yakju. As the result of sensory test, higher scores for smell and color were found for the Yakju used Hanarum Yakju. The highest score sweat and acid were found for the Anda rice Yakju in sensory test. The result of sensory evaluation indicated that Hanarum Yakju and Anda Yakju were better than the other samples, and the value of bitterness was no significant in this test.

Baechu kimchi without cuttlefish (control), baechu kimchi with cuttlefish (CK), cuttlefish baechu kimchi with yogurt (CK+Y), and cuttlefish baechu kimchi with vitamin C (CK+VC) were prepared, and the fermentation characteristics of the prepared kimchi samples were investigated during 28 days of fermentation at 4℃. The levels of moisture, crude lipid, and crude ash did not differ much among the samples, but the crude protein levels of CK, CK+Y, and CK+VC were greater than that of the control. The pH values of CK+Y and CK+VC slowly decreased compared with those of the control and CK during fermentation. The acidity increased sharply until 21 days then gradually increased thereafter. The total microbial counts achieved maximum levels at 21 days, and the kimchi to which yogurt and vitamin C were added showed values lower than that of the control. The number of Leuconostoc sp. in CK+Y and CK+VC was higher than that in the control. In our sensory evaluations, cuttlefish kimchi with yogurt or vitamin C scored highest in terms of texture, sour taste, ripened taste, and overall acceptability.

The fermentation and quality characteristics of Cheonggukjang with Chinese cabbage, which is produced as a by-product in the kimchi industry, were investigated. Cheonggukjang was prepared with cooked soybean without Chinese cabbage (control), with 10% Chinese cabbage (A10), and with 20% Chinese cabbage (A20), respectively. The A10 and A20 pH values did not show a significant difference compared with the control during fermentation for 72 h. The total aerobes of the Cheonggukjangs reached 8.65 (control), 8.73 (A10), and 9.11 (A20) log CFU/mL after fermentation for 72 h at 37°C, respectively. The numbers of lactic acid bacteria were found to be 5.62 (A10) and 5.87 (A20) log CFU/mL during fermentation for 72 h at 37°C, but lactic acid bacteria were not detected in the control. The amino nitrogen and viscous substance contents of A10 and A20 were lower than those of the control. The total polyphenol contents and DPPH radical scavenging abilities of the tested Cheonggukjang were increased by fermentation. The increasing ratio of polyphenol and the DPPH radical scavenging ability of A10 were higher than those of the control and of A20. The sensory quality of A10 was higher than that of the control and of A20 in taste, color, and overall acceptability.

Cheongkookjang that was prepared with three kinds of soybeans [non-germinated soybean (NG), soybeans germinated for 12 hr (GS12), and soybeans germinated for 24 hr (GS24)] were investigated. The changes in the pH, total aerobes, and slime content of Cheongkookjangs that were prepared with NG, GS12 and GS24 did not significantly differ during their fermentation for 48 hr at 40℃. The total aerobes of the Cheongkookjang variants reached 108~109 CFU/mL after theirfermentation for 48 hr. The total polyphenol content and DPPH-radical-scavenging activities the germionated and non-germinated soybeans did not significantly differ, but increased significantly according to the germination degree during the fermentation. The isoflavone content of the Cheongkookjang with the germinated soybean increased. The isoflavone content of Cheongkookjang variant were 0.141 mg/g (NG), 0.369 mg/g (GS12) and 0.569 mg/g (GS24); their free amino acid contents were 254.26 mg% (NG), 337.49 mg% (GS12) and 528.78 mg% (GS24); and their sensory characteristics such as their taste, color, flavor, bitter taste, texture, and overall acceptability did not significantly differ.

In this study, we investigated quality and fermentation characteristics in baechu kimchi containing 0(control), 5(GK5), 10(GK10), 15(GK15) and 20(GK20)% of shred garlic. Analysis was performed during fermentation at 4℃ for 42 days, every 7 days. The result showed significant changes in color value between control group and garlic added groups. Hunter’s color L value was increased during fermentation whereas a and b value were decreased. Hardness of kimchi was higher in 15% and 20% garlic added groups than other groups. The pH decreased significantly during fermentation, while titratable acidity was showed reverse tendency during fermentation period. The reducing sugar content was decreased in all groups during fermentation period, which higher in GK10 and GK15 group than the others. But its remaining ratio was 19.7∼22.3% and not showed significant difference in experimental groups at 42 days fermentation. The number of lactic acid bacteria was dramatically increased up to 6.13∼7.60 log CFU/g at 7∼14 days fermentation. The garlic was inhibited significantly the growth of lactic acid bacteria, but this was not showed significant difference between garlic added groups and control group, after 28 days fermentation. As a results, we suggest that addition of garlic increase the quality characteristics and storage properties of Kimchi, and not hinder quality of kimchi at addition level of 20% than salted baechu.

The characteristics of the narirutin-added alcohol fermentation of citrus hydrolysates were investigated to produce functionally improved citrus wine. The pH of narirutin-added citrus wine ranged from 3.38 to 3.51, and the titratable acidity was about 0.55% which show no significant differences attributable to the narirutin quantity. With regard to the color and brown color, with the addition of more narirutin, the a value was decreased while the b value and brown color increased. The sugar content decreased from 24 to 8.0-8.5 ˚Brix after alcohol fermentation, and the alcohol content appeared to be between 14.5 and 14.6% in all the sections. For the free sugar contents, the glucose and fructose contents were relatively high in every section. For the total polyphenol content, it was shown to increase when more narirutin was added. and the 2%-narirutin-added section showed the highest polyphenol content(46.44 mg%). The results of sensory evaluation were that the color, flavor and bitterness increased while the sweetness and overall acceptability were reduced by the additional narirutin. Functionally improved citrus wine can be produced by using narirutin, but more researches regarding quality improvement should be carried out to overcome the bitterness.

국산 캠벨 얼리 포도과즙을 36 로 동결농축한 후 국산 포도로부터 분리된S. cerevisiae S13, D8 균주를 이용하여 아이스와인의 발효를 행하면서 대조균주인 S. cerevisiae Fermivin과 발효특성을 비교하였다. 발효 중 S13과 D8의 경우 Fermivin보다 당도가 다소 빠르게 감소하였으며 빠른 알코올 생성을 보였다. 발효 종료 시점인 9일 후의 알코올 농도는 D8이 15.2%, S13은 14.0%, Fermivin은 12

본 연구에서는 참외를 이용한 알코올 발효과정에서 효모에 따른 발효 특성을 비교 조사하였다. 그 결과 pH, 총산도 및 당도는 효모에 따른 큰 차이를 보이지 않았으며 발효과정에서 pH는 일정하게 유지되었으나 총산도는 증가하는 경향으로 나타났다. 당도는 발효 3일째부터 급격하게 감소하여 발효 후 약 7 로 감소하였다. 유기산 함량은 모든 구간에서 lactic 및 citric acid의 함량이 가장 높게 나타나주요 유기산으로 나타났다. 유리당 함량은