• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.1-7
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• 1997

The efficient manufacture of fermented dairy products on an industrial scale requires a supply of reliable starter cultures with properties suited to desired product specifications. These cultures must be backed by relevant research and development activities. This article describes the issues involved in establishing a centre to provide starter culture R & D for a group of independent cheese manufacturing companies, and discusses a strategic approach to the management of starter cultures.

• 한국축산식품학회지
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• 제42권6호
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• pp.1009-1019
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• 2022

In recent years, biocontrol of foodborne pathogens has become a concern in the food industry, owing to safety issues. Listeria monocytogenes is one of the foodborne pathogens that causes listeriosis. The major concern in the control of L. monocytogenes is its viability as it can survive in a wide range of environments. The purpose of this study was to isolate lactic acid bacteria with antimicrobial activity, evaluate their applicability as a cheese starter, and evaluate their inhibitory effects on L. monocytogenes. Lactococcus lactis strain with antibacterial activity was isolated from raw milk. The isolated strain was a low acidifier, making it a suitable candidate as an adjunct starter culture. The commercial starter culture TCC-3 was used as a primary starter in this study. Fresh cheese was produced using TCC-3 and L. lactis CAU2013 at a laboratory scale. Growth of L. monocytogenes (5 Log CFU/g) in the cheese inoculated with it was monitored during the storage at 4℃ and 10℃ for 5 days. The count of L. monocytogenes was 1 Log unit lower in the cheese produced using the lactic acid bacteria strain compared to that in the cheese produced using the commercial starter. The use of bacteriocin-producing lactic acid bacteria as a starter culture efficiently inhibited the growth of L. monocytogenes. Therefore, L. lactis can be used as a protective adjunct starter culture for cheese production and can improve the safety of the product leading to an increase in its shelf-life.

• Journal of Microbiology and Biotechnology
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• 제30권9호
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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.

• 한국축산식품학회지
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• 제39권5호
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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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• 제36권2호
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• pp.125-131
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• 2018

The present study aimed to investigate the microbial diversity in Gouda cheese within the four months of ripening, via next-generation sequencing (NGS). Lactococcus (96.03%), and Leuconostoc (3.83%), used as starter cultures, constituted the majority of bacteria upon 454 pyrosequencing based on 16S rDNA sequences. However, no drastic differences were observed among other populations between the center and the surface portions of Gouda cheese during ripening. Although the proportion of subdominant species was <1%, slight differences in bacterial populations were observed in both the center and the surface portions. Taken together, our results suggest that environmental and processing variables of cheese manufacturing including pasteurization, starter, ripening conditions are important factors influencing the bacterial diversity in cheese and they can be used to alter nutrient profiles and metabolism and the flavor during ripening.

• 기술사
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• 제18권4호
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• pp.5-11
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• 1985

치즈의 기존제조공정상의 문제점을 조사정리하였고, 또 새로운 치즈의 숙성법으로 Cheese Slurry를 이용한 제조법을 시험하였다. Cheese Slurry는 제방, 제과에 좋은 영양의 보강과 풍미를 내는데 가장 적합한 재료로써 잠재력이 큰 것으로 판단되었다. 이 새로운 방법은 치즈의 재래식방법을 약간 변형시켜 적당한 Starter Culture을 이용함으로써 제품의 풍미향상과 제조기간 단축에 뚜렷한 효과를 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.795-802
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• 2014

The aim of this study was to determine the effects of temperature and supplementation with skim milk powder (SMP) on the microbial and proteolytic properties during the storage of cottage cheese. Cottage cheese was manufactured using skim milk with 2% SMP and without SMP as the control, and then stored at $5^{\circ}C$ or $12^{\circ}C$ during 28 days. The chemical composition of the cottage cheese and the survival of the cheese microbiota containing starter lactic acid bacteria (SLAB) and non-starter culture lactic acid bacteria (NSLAB) were evaluated. In addition, changes in the concentration of lactose and lactic acid were analyzed, and proteolysis was evaluated through the measurement of acid soluble nitrogen (ASN) and non-protein nitrogen (NPN), as well as electrophoresis profile analysis. The counts of SLAB and NSLAB increased through the addition of SMP and with a higher storage temperature ($12^{\circ}C$), which coincided with the results of the lactose decrease and lactic acid production. Collaborating with these microbial changes, of the end of storage for 28 days, the level of ASN in samples at $12^{\circ}C$ was higher than those at $5^{\circ}C$. The NPN content was also progressively increased in all samples stored at $12^{\circ}C$. Taken together, the rate of SLAB and NSLAB proliferation during storage at $12^{\circ}C$ was higher than at $5^{\circ}C$, and consequently it led to increased proteolysis in the cottage cheese during storage. However, it was relatively less affected by SMP fortification. These findings indicated that the storage temperature is the important factor for the quality of commercial cottage cheese.

• Journal of Dairy Science and Biotechnology
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• 제33권4호
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• pp.247-252
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• 2015

본 연구는 원유로부터 면역효능이 우수한 젖산균 Streptococcus macedonicus LC743을 분리하였고, 이 균으로 제조한 모짜렐라 치즈와 상업균주로 제조한 모짜렐라 치즈에 대해 물성학적 특성을 비교시험 하였다. S. macedonicus LC743을 이용한 절단 전 커드의 조직특성은 상업균주로 제조된 절단 전 커드보다 조직이 약한 반면, 상업균주와 S. macedonicus LC743 균주로 제조된 절단 전 커드보다 강하거나 비슷한 수준을 보였다. 치즈의 경우는 S. macedonicus LC743으로 제조된 치즈가 Hardness, Sprininess, Cohesiveniss, Gumminess, Chewiness에서, Fracturability는상업균주로제조한치즈에서, Adhesiveness는 상업균주와 S. macedonicus LC743으로 제조된 치즈에서 각각 높은 값을 나타내었다. 전자현미경 관찰에서 상업균주로 제조된 치즈는 표면이 거친 모습을 보인 반면, S. macedonicus LC743로 제조된 치즈는 케이신 마이셀이 작은 덩어리가 뭉쳐져 있어 작은 계곡을 형성하는 것을 볼 수 있었다.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.99-105
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• 1994

In this study we compared traditional cheesemaking process with the process utilizing ultrafiltration(UF) system. The whole milk retentates were prepared by ultrafiltration to volume concentration ratio(VCR) of 2.00:1, 2.25:1 and 2.50:1. Along with the untreated whole milk, there were studies in terms of the change of pH, titratable acidity and Soxhlet-Henkel($\circ $SH) value by mesophilic lactic starter and curd formation by rennet during Gouda cheese manufacture. Due to the increase of buffering effect titratable acidity and $\circ $SH value increased with the higher concentration ratio. When inoculated with the same volume of mesophilic lactic starter, less pH change occurred in UF retentates than in control milk. When added 0.0025% rennet, UF retentates coagulated 16~ 17 minutes ealier then the control milk. Gouda cheese yield from raw milk and UF retentates was 12.5~13.1% equally, but yield efficiency of UF retentate cheese was slightly higher than that of the raw milk cheese. Quantity of whey from retentate cheese was inversely related to VCR. But whey from retentate cheese contained higher percentage of amjor components than that from control milk cheese. In early ripening, the concentrations of lactose and soluble nitrogen compound were higher in retentate cheeses. Lactose content of control milk cheese was 3.49% and that of 2.00:1. 2.25:1, 2.50:1 VCR retentate was 3.77%, 4.89%, 7.03%, respectively. Thus, the more concentrated cheese contained a higher amount of lactose and all the lactose was hyerolyzed durion 35-day ripenion period. Soluble nitrogen compound of control milk cheese was 1.22% and that of UF cheeses was 1.82~2.06%. After 20-day ripening, soluble nitrogen compound increased starply in UF cheese.

• 한국축산식품학회지
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• 제37권5호
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• pp.773-779
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• 2017

The effect of addition of the probiotic Bifidobacterium longum KACC 91563 on the chemical and sensory properties of Kwark cheese produced using CHN-11 as a cheese starter were investigated. The addition of B. longum KACC 91563 to Kwark cheese did not change the composition or pH value of the cheese, compared with control. B. longum KACC 91563 survived at a level of 7.58 Log CFU/g and did not have any negative effect on survival of the cheese starter. A sensory panel commented that the addition of B. longum KACC 91563 made Kwark cheese more desirable to consumers, and that the probiotic supplementation had no effect on perceived taste. Thus, B. longum KACC 91563 can be used for inclusion of probiotic bacteria in cheese.