• Journal of the East Asian Society of Dietary Life
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• v.16 no.3
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• pp.349-356
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• 2006

This study was carried out to survey the effect of Jujube extract on the growth of 3 strains of lactic acid bacteria(LBA) starter cultures in the MRS broth by the addition of 0, 0.1, 0.5, 1 and 2% extract The pH, titratable acidity and OD of LAB were investigated in order to get fundamental knowledge for the development a new product. The effects of Jujube extract on the growth of LAB were variable depending upon the LAB species and concentrations of Jujube extract significantly (p<0.05). In the results, Jujube extract enhanced the acid production and propagation by the 3 LAB strains with increasing concentration of Jujube extracts until 2.0% added was to the MRS broth medium (p<0.05). Addition of Jujube extract markedly stimulated the acid production and propagation of Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium longum.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.518-522
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• 2005

Yogurt containing high ${\gamma}$-aminobutyric acid (GABA) was developed using lactic acid bacteria and germinated brown rice. Lactobacillus acidophilus, L. plantarum, and L. brevis OPY-1 strains were inoculated into Lactobacillus MRS broth for use as yogurt starter. After treatment with 5% monosodium glutamate in MRS broth, L. brevis OPY-1 strain isolated from Kimchi produced GABA concentration of 8,003.28 nmol/mL. Starter was inoculated into fermentation substrate mixture containing germinated brown rice extract and blend of powdered whole milk and skim milk. Samples were incubated, and viable cell colonies were counted. Highest number of lactic acid bacteria was reached between 16 and 20 hr. Concentrated rice milk fermented with high GABA-producing strain contained GABA concentrations of $137.17\;{\mu}g/g$ D.W., whereas concentrated fermented milk prepared by conventional method contained GABA of $1.29\;{\mu}g/g$ D.W. Sensory evaluation panelists gave favorable ratings to fermented rice milk containing high GABA concentration.

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1404-1411
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• 2020

Lactic acid bacteria (LAB) play an important role in dairy fermentations, notably as cheese starter cultures. During the cheese production and ripening period, various enzymes from milk, rennet, starter cultures, and non-starter LABs are involved in flavor formation pathways, including glycolysis, proteolysis, and lipolysis. Among these three pathways, starter LABs are particularly related to amino acid degradation, presumably as the origins of major flavor compounds. Therefore, we used several enzymes as major criteria for the selection of starter bacteria with flavor-forming ability. Lactococcus lactis subsp. lactis LDTM6802 and Lactococcus lactis subsp. cremoris LDTM6803, isolated from Korean raw milk and cucumber kimchi, were confirmed by using multiplex PCR and characterized as starter bacteria. The combinations of starter bacteria were validated in a miniature Gouda-type cheese model. The flavor compounds of the tested miniature cheeses were analyzed and profiled by using an electronic nose. Compared to commercial industrial cheese starters, selected starter bacteria showed lower pH, and more variety in their flavor profile. These results demonstrated that LDTM6802 and LDTM6803 as starter bacteria have potent starter properties with a characteristic flavor-forming ability in cheese.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.534-541
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• 2018

Kimchi (a traditional Korean fermented vegetable) was prepared with a starter, Lactobacillus zymae GU240 producing ${\gamma}$-aminobutyric acid (GABA), and one precursor of GABA (glutamic acid, glutamic acid monosodium salt (MSG), or kelp extract). L. zymae GU240, an isolate from kimchi, can grow at 7% NaCl and low temperature. Five different kimchi samples were fermented for 20 weeks at $-1^{\circ}C$. Kimchi with starter alone could not produce GABA. The GABA content was highest in kimchi with co-inoculation of the starter and MSG (1% (w/w)). Kimchi co-inoculated with the starter and kelp extract powder (3% (w/w)) had the second highest GABA content. Addition of glutamic acid powder (1% (w/w)) caused a reduction in the pH level of kimchi and growth inhibition of lactic acid bacteria and yeasts. Kimchi samples with MSG or kelp extract showed improvement of sensory evaluation scores. The results demonstrate the possibility to produce kimchi with improved functionality and taste by using L. zymae GU240 as a starter along with a suitable precursor such as MSG or kelp extract.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.201-207
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• 1998

In order to evaluate the effects of addition of soybean boiling waste liquor (SBWL) and sugar and inoculation of the lactic acid bacteria and yeast starter culture in Korean traditional kanjang mash, three types of kanjang were prepared in a clay pot of 100 l volume and compared the characteristics of lactic acid fermentation. The mashing compositions of the types of kanjang were as follows: (1) control treatment mash was prepared with meju : 20% salt solution (1:4) and SBWL, (2) kanjang mash with 3.5% added sugar to the control type mash and (3) kanjang mash with 3.5% added sugar and inoculation of the lactic acid bacteria and yeast starter culture 35 days after mashing to the control type mash. (1), (2) and (3) of kanjang mash were found to be effective in increasing the lactic acid content and improving the organoleptic characteristics of kanjang. But the effect of yeast starter culture was not clear because osmophilic yeasts were inhibited by metabolite(acetic acid) produced by lactic acid bacteria. The lactic acid content of (1), (2) and (3) kanjang was 2.05, 2.38 and 2.91% respectively in 90 day-matured kanjang.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.199-207
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• 2013

This study was performed to evaluate the quality characteristics of sourdough bread with addition of lactic acid bacteria (LAB) in the antibacterial activity. The starter cultures were used for sourdough bread to increase bread shelf-life: Lactobacillus fermentum, Lactobacillus paracasei KB28, and Pediococcus pentosaceus MJK7. The results showed that the viable counts of lactic acid bacteria were increased in 8.1~9.2 log $cfu/m{\ell}$, respectively. The pH of the three sourdoughs was lower than that of control. In the texture characteristics, hardness, gumminess, and chewiness were tended to increase on the sourdough bread. Among the three sourdough breads, bread volume and retrogradation of bread were not significantly different. According to the results from preservation period, the sourdough breads with addition of Lb. paracasei KB28, Ped. pentosaceus MJK7 were showed the appearance of mold and bacteria growth in 5~6 days, whereas the control were showed in 3 days. As a result, a sensory evaluation indicated the highest overall acceptance in order of Lb. fermentum, Lb. paracasei KB28, Ped. pentosaceus MJK7. Based on these results, Lb. paracasei KB28 can be applicable to improve the quality of sourdough bread.

• Food Science of Animal Resources
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• v.39 no.5
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• pp.804-819
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• 2019

Ezine cheese is a non-starter and long-ripened cheese produced in the Mount of Ida region of Canakkale, Turkey, with a protected designation of origin status. Non-starter lactic acid bacteria (NSLAB) have a substantial effect on the quality and final sensorial characteristics of long-ripened cheeses. The dominance of NSLAB can be attributed to their high tolerance to the hostile environment in cheese during ripening relative to many other microbial groups and to its ability to inhibit undesired microorganisms. These qualities promote the microbiological stability of long-ripened cheeses. In this study, 144 samples were collected from three dairies during the ripening period of Ezine cheese. Physicochemical composition and NSLAB identification analyses were performed using both conventional and molecular methods. According to the results of a 16S rRNA gene sequence analysis, 13 different species belonging to seven genera were identified. Enterococcus faecium (38.42%) and E. faecalis (18.94%) were dominant species during the cheese manufacturing process, surviving 12 months of ripening together with Lactobacillus paracasei (13.68%) and Lb. plantarum (11.05%). The results indicate that NSLAB contributes to the microbiological stability of Ezine cheese over 12 months of ripening. The isolation of NSLAB with antimicrobial activity, potential bacteriocin producers, yielded defined collections of natural NSLAB isolates from Ezine cheese that can be used to generate specific starter cultures for the production of Ezine cheese (PDO).

• Journal of Dairy Science and Biotechnology
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• v.41 no.3
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• pp.138-148
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• 2023

In this study, Lactococcus lactis subsp. hordniae JNU533 (JNU533) was isolated from Swiss-type cheese, and the bacteriocin produced by this strain was characterized. The spot-on-lawn assay was used to determine the antimicrobial spectrum and characteristics of the JNU533-derived bacteriocin. Results confirmed that the JNU533-derived bacteriocin inhibited the growth of lactic acid bacteria. The size of the bacteriocin was approximately 4.9 kDa, and it was heat- and pH-stable under various temperature and pH conditions. Furthermore, the possibility of using JNU533 as a starter culture in the manufacturing of fermented dairy products was assessed. A single colony of JNU533 was inoculated into 10% skim milk containing 0.5% glucose to investigate its characteristics in milk culture. The decrease in the pH was similar to that elicited by Lactobacillus delbrueckii subsp. bulgaricus. Furthermore, the results confirmed that JNU533 inhibited the growth of various bacteria and could be used as a milk fermentation starter. This study highlights the characteristics of the bacteriocin produced by JNU533 and the growth features of this strain in a skim milk medium.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.676-681
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• 2001

This study was carried out to evaluate the quality characteristics of frozen soy yogurts prepared with different proteolytic enzymes and starter culture. The viable cell counts of lactic acid bacteria in frozen soy yogurts were measured $10^8$ CFU/g by the single culture method, while $10^9$ CFU/g by the mixed culture method except ${\alpha}-chymotrypsin$ treatment. The viable cell counts of lactic acid bacteria did not decrease after freezing for 30 min in ice cream maker. The lactic acid bacteria from the mixed culture showed better bile acid tolerance than those from the single culture. The lactic acid bacteria from the frozen soy yogurt prepared with ${\alpha}-chymotrypsin$ and mixed culture of Bifidobacterium bifidum and Lactobacillus bulgaricus showed better acid tolerance and bile acid tolerance. The highest(73.45%) overrun was observed in the frozen soy yogurt treated with ${\alpha}-chymotrypsin$ and mixed culture of B. bifidum and L. bulgaricus. The melt-down percent was higher in the single culture than the mixed culture. In sensory test, the frozen soy yogurt prepared with ${\alpha}-chymotrypsin$ and mixed culture of B. bifidum and L. bulgaricus was the most desirable, the highest scores in sourness, bitterness and mouthfeel.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.307-314
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• 1999

This study was aimed at the investigation of the possibility of the addition of lactic acid bacteria as "starter"for the preparation of radish juice. Forty strains of lactic acid bacteria were isolated from dongchimi that was fermented by a traditional method. The isolates were assorted into 5groups, Leuconostoc mesenteroides subsp. mesenteroides (J-9), Lacobacillus brevis (J-12), Lactobacillus fermentum (J-7), Lactobacillus sake (J-20), and Lactobacillus plantarum (J-39). Leuconostoc mesenteroides was predominated in the sample of dongchimi with frequency of 52.5%. Each of the strain, which exhibited the beat growth in the species, was selected in the 5species, and investigation of the fermentation characteristcis was carried out. The fermentation were performed for 9 days at 25${\circ}C$ after the inoculation of 0.3% ($10^{6}$ cfu/㎖) to each ultra-filtrated radish juice. The pH, total acidity, content of non-volatile organic acids were examined during the fermentation period. Lactobacillus plantarum showed the highest growth rate and the growth rate of Lactobacillus sake was the lowest. The pH (6.3-6.36) and total acidity (0.09-1.0 %) fo the ultrafiltrated radish juice before fermentation were changed to 3.2-4.3 and 0.65-1.2% after 9days, respectively. The changes of the pH and total acidity were related with the growth of the lactic acid bacteria; the better growth of lactic acid bacteria, the more rapid decrease of pH and increase of the total acidity. when the amount of non-volatile organic acids were estimated during fermentation, citric acid, malic acid, malonic acid, and succinic acid were decreased in all cases. However, the content of lactic acid increased with the progression of fermentation. L. mesenteroides (J-9), L. brevis (J-12) and L. fermentum (J-7) were chosen for the candidates of the starter for the lactic fermentation of radish juice based on the biochemical analysis and sensory evaluation.