• The Korean Journal of Food And Nutrition
• /
• v.10 no.1
• /
• pp.122-126
• /
• 1997

Bifidobacteria have been known as beneficial inhabitant of human intestine. Therefore, bifidobacteria began to be noticed as a starter in the manufacture of fermented dairy products. Perhaps the key for effective use of bifidobacteria in commercial dairy products is the maintenance of viability of bifidobacteria during large scale preparation of starter culture and distribution of products. So we tried to obtain the bifidobacteria having suitable characteristics for using as a starter in the manufacture of fermented dairy products. Among bifidobacteria isolated from Korean, E-4 strain showed the highest resistance to oxygen. To know whether the selected strain will be fit for manufacture of fermented dairy products, we also investigated resistance of the selected strain to HCI. The selected strain, E-4, was more resistant to environmental stresses such as oxygen, H2O2 and HCI than Bifidobacterium longum known as resistant strain to environmental stresses. According to carbohydrate fermentation patterns and morphological characteristics, E-4 strain was identified as B. bifidum. In conclusion, the selected strain, E-4, was thought to be fit for manufacture of fermented dairy products.

• Food Science and Biotechnology
• /
• v.16 no.5
• /
• pp.812-816
• /
• 2007

To overcome the problem of ginseng's earthy smell in the manufacture of ginseng wine, we used dried ginseng powder that was extrusion-cooked at $125-168^{\circ}C$ in the wine making process. By using a ginseng powder that was extrusion-cooked at higher temperatures, fermentation by Maillard reaction products (MRPs) was delayed, and the acidic pH that results from extrusion cooking was improved. At $15^{\circ}C$ with glucose instead of sucrose, an addition of 0.5%(w/v) diammonium phosphate (DAP) to the $125^{\circ}C$ extrusion-cooked ginseng powder reduced the primary fermentation time to 11 days versus 33 days without DAP. In the absence of DAP, by increasing the fermentation temperature from 15 to $30^{\circ}C$, increasing the starter yeast inoculate from 0.02 to 1 %, and by increasing the amount of ginseng extrudate from 1 to 2%, fermentation time was effectively reduced more than 10-fold. The results of this study may provide information for the alcohol fermentation of materials containing MRPs as well as for poor nitrogen sources.

• Korean Journal of Microbiology
• /
• v.51 no.4
• /
• pp.419-426
• /
• 2015

The aims of this study were to isolate spore-forming Bacillus strains that exhibit high digestibility and anti-pathogenic bacteria toward feed for calves. Total 136 spore-forming strains were isolated from finished feeds and their ingredients. Among them, 93 strains were identified as Bacillus species when analyzed by 16S rRNA sequencing. For industrial use, three strains named as Bacillus licheniformis SHS14, B. subtilis LCB7, B. amyloliquefaciens LCB10 were selected after evaluating the industrial standards that are related with heat and acid resistance, enzyme activities, and anti-pathogenic activities against Samonella dublin ATCC15480 and E. coli K99. After each culture, 3 selected strains were mixed together at 1:1:1 (v/v/v) ratio and then prepared as the mixed starter culture for feeding. The changes in microbial community were analyzed via 16S rRNA metagenomics. The initial community ratio among three strains was maintained even after manufacturing into final products. Also, in vitro, enzymatic and anti-pathogenic activities were almost same as those when cultured in single culture, and results of anti-pathogenic activities conducted with calves showed 90% activities against lincomycin, which would be indicative of a promising feed starter.

• Journal of the East Asian Society of Dietary Life
• /
• v.26 no.2
• /
• pp.163-170
• /
• 2016

This study investigated the quality characteristics of doenjang prepared with different Bacillus strains (Bacillus subtilis KACC 15935 and Bacillus subtilis HJ18-9). Changes in enzyme activities (protease, cellulase, and ${\alpha}-amylase$), amino-type nitrogen and ammonia-type nitrogen contents, and reducing sugar were investigated during the fermentation period. Enzymes such as protease, cellulase, and ${\alpha}-amylase$ play important roles in the composition of nutrients, as well as in the flavor and taste of doenjang. After 60 days of fermentation, protease activities in control doenjang, and doenjang fermented with B. subtilis KACC 15935, and B. subtilis HJ18-9 increased significantly up to $382.58{\pm}4.02$, $342.58{\pm}7.94$, and $392.58{\pm}1.91unit/g$, respectively (p<0.05). At the beginning of fermentation, protease activities were in the range of 156.88~182.71 unit/g. Cellulase and ${\alpha}-amylase$ activities of doenjang in HJ18-9 were higher than those in other samples. After fermentation, amino-type nitrogen in doenjang fermented with control, B. subtilis KACC 15935, and B. subtilis HJ18-9 increased significantly up to $143.25{\pm}1.62$, $141.86{\pm}2.14$, and $150.23{\pm}1.62mg%$, respectively (p<0.05). These results suggest that B. subtilis HJ18-9 is a suitable starter for the preparation of doenjang.

• Journal of Dairy Science and Biotechnology
• /
• v.40 no.3
• /
• pp.93-102
• /
• 2022

This study was conducted using response surface methodology (RSM) to elucidate fermentation conditions that will optimize ACE inhibitory activity using Lactiplantibacillus plantarum K79. Four independent variables [skim milk (with 1% added glucose) concentration (6%-14%), incubation temperature (32℃-42℃), incubation time (8-24 h), and amount of added starter (0.02%-0.2%)] were evaluated using five-level central composite design and response surface methodology to determine the optimum fermentation condition. The dependent variables were angiotensin converting enzyme (ACE) inhibitory activity (the value obtained from 102 diluted supernatant), and pH. The respective coefficients of determinations (R²) were 0.791 and 0.905 for ACE inhibitory activity and pH. The maximum ACE inhibitory activity was 90% under the following conditions: 10% skim milk (with 1% added glucose) concentration, 37℃ incubation temperature, 17.8 h incubation time, and 0.2% added starter. Based on the RSM, using predicted best ACE conditions for fermentation of 13.49% skim milk (with 1% added glucose) with 0.0578% starter at 33.4℃ for 21.5 h, the predicted ACE inhibitory activity and pH values were 86.69% and 4.6, respectively. Actual ACE inhibitory activity and pH values were 85.5% and 4.58, respectively

• Microbiology and Biotechnology Letters
• /
• v.26 no.2
• /
• pp.151-160
• /
• 1998

The Leuconostoc paramesenteroides dominated at refrigeration temperature range was isolated from kimchi, and improved its growth properties by mutation for competitive growth against Lactobacillus plantarum at lower pH. It was found that the minimal pH for the wild type Leuconostoc paramesenteroides Pw growth was pH 4.5 adjusted with HCI and pH 5.0 adjusted with organic-mixture (lactic acid:acetic acid=1:2), respectively. The mutant P-100 could grow in pH 4.0, 4.5, respectively, in MRS broth. Two strains Pw and P-100 were added into kimchi as starter and compared the quality characteristics of kimchi. The total acceptability of Pw and P-100 inoculated kimchi were evaluated better than that of control kimchi (no starter added) by sensory test and extended the optimal pH range of kimchi up to about 2.2, 2.5 times, respectively. In kimchi added P-100, the succinic acid was more abundant than others and the total number of Lactobacillus plantarum was down about 2.5 times in contrast to control kimchi.

• Culinary science and hospitality research
• /
• v.18 no.4
• /
• pp.183-198
• /
• 2012

The purpose of this study is to determine potential effectiveness of sourdough starter powder (made of Korean wheat flour) in the quality characteristics of bread and in the substitution effect of a dough improver in bread baking. The bread containing sourdough starter powder was considered to be most suitable for making sourdough bread. As a result, SP 10 showed the best fermentation rate and the highest volume and specific volume. In sensory testing, SP 10 was most preferable among others. According to experimental comparison between optimal addition ratio of SP 10 and other sourdough starter powder products available in Korean domestic market, SI had the highest fermentation rate, highest volume and specific volume. Analysis of texture showed that SI was soft with the lowest hardness and the highest elasticity. Sensory test showed that SI was most preferable of all, and SP 10 was more preferable than BP. It was concluded that SP 10 was not less preferable in the aspect of preference at sensory test than other products. Hence, it is expected that sourdough starter powder made of Korean wheat flour will be possibly more popular and effective in replacing some portion of dough improver of baking.

• Mycobiology
• /
• v.42 no.4
• /
• pp.353-360
• /
• 2014

Makgeolli is a traditional Korean alcoholic beverage. The flavor of makgeolli is primarily determined by metabolic products such as free sugars, amino acids, organic acids, and aromatic compounds, which are produced during the fermentation of raw materials by molds and yeasts present in nuruk, a Korean fermentation starter. In this study, makgeolli was brewed using the wild yeast strain Saccharomyces cerevisiae Y98-5, and temporal changes in the metabolites during fermentation were analyzed by ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. The resultant data were analyzed by partial least squares-discriminant analysis (PLS-DA). Various metabolites, including amino acids, organic acids, sugar alcohols, small peptides, and nucleosides, were obviously altered by increasing the fermentation period. Changes in these metabolites allowed us to distinguish among makgeolli samples with different fermentation periods (1, 2, 3, 6, 7, and 8 days) on a PLS-DA score plot. In the makgeolli brewed in this study, the amounts of tyrosine ($463.13{\mu}g/mL$) and leucine ($362.77{\mu}g/mL$) were high. Therefore, our results indicate that monitoring the changes in metabolites during makgeolli fermentation might be important for brewing makgeolli with good nutritional quality.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.1
• /
• pp.53-60
• /
• 1999

Possibility of utilization of fig as a source of vinegar was tested. Alcohol fermentation was conducted by inoculation of Saccharomyces bayanus into fig juice. After 5 days of fermentation at 27oC, fig wine with alcohol content of 13.6%. Then fig vinegar was produced by cultivation of Acetobacter sp. E which was isolated from fig vinegar. Optimum concentration of alcohol, starter content and fermentation temperature for the acid production were 8~9%, 5% and 27~30oC, respectively. More acetic acid was produced by adding 0.5% of yeast extract and 0.01% of Ca pantothenate. Adjustment pH of culture broth with acetic acid and shaking cultivation method were not effective in higher yield of acid production. Addition of sulfite up to 50 ppm did not inhibit for acetic acid fermentation. Addition of 1% bentonite or 1% kakishibu was more effective for the clarification of fig vinegar than any other clarifying agents tested. During aging and racking, acidity, absorbance and tannin content of fig vinegar decreased, while redness and yellowness increased. Aged and racked fig vinegar showed higher sensory score than non aged one in the aspects of color and overall acceptability.

• Food Science of Animal Resources
• /
• v.41 no.6
• /
• pp.1078-1094
• /
• 2021

This research investigated the physio-chemical and microbial quality characteristics of dry fermented sausage from selected Pediococcus strains: P. acidiliactici (PE1) and P. pentosaceus (PE2) as compared to commercial starter culture (COS) during fermentation and ripening. Treatments showed no substantial variation (p<0.05) in water activity (a_w) values across the study period. PE1 and PE2 treatments exhibited similar (p>0.05) pH values and presented remarkable (p<0.05) lower volatile basic nitrogen (VBN) and thiobarbituric acid reactive (TBARS) content than COS treatment throughout the ripening period. However, the pH values in COS batch were considerably lower than others. PE1 samples presented a significant highest (p<0.05) counts both in lactic acid bacteria (LAB) and total plate count (TPC) than COS and PE2 treatments at 7 days fermentation, and it resulted in a similar and higher TPC count as COS after the ripening period. After the ripening process, treatments are ordered based on LAB counts as follows: COS>PE1>PE2. All batches presented similar redness and yellowness attributes since the 7 days of fermentation and in lightness across the study period. Treatments were similar (p>0.05) in springiness and chewiness traits across the study period and in hardness characteristics in the ripened products. Cohesiveness was higher in PE1 and COS batches. No variation (p>0.05) in aroma and sourness sensory attributes of treatments. The color attribute was highest (p<0.05) in PE1 and PE2 treatments and PE1 had the highest overall acceptability. The overall outstanding merit exhibited by PE1 can be utilized in the commercial production of high-quality dry fermented sausage.