• Journal of Microbiology and Biotechnology
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• 제26권4호
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• pp.666-674
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• 2016

The bacterial strains were screened as potential starters for fermenting low-salt doenjang (a Korean traditional fermented soybean paste) using Korean doenjang based on proteolytic and antipathogenic activities under 6.5-7.5% NaCl conditions. Phylogenetic analysis based on 16S rRNA gene sequences showed that they all belonged to the genus Bacillus. Proteolytic and antipathogenic activities against Escherichia coli, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Aspergillus flavus, as well as fibrinolytic, amylase, and cellulase activities of the 10 strains were quantitatively evaluated. Of these, strains D2-2, JJ-D34, and D12-5 were selected, based on their activities. The functional, phenotypic, and safety-related characteristics of these three strains were additionally investigated and strains D2-2 and D12-5, which lacked antibiotic resistance, were finally selected. Strains D2-2 and D12-5 produced poly-γ-glutamic acid and showed various enzyme activities, including α-glucosidase and β-glucosidase. Growth properties of strains D2-2 and D12-5 included wide temperature and pH ranges, growth in up to 16% NaCl, and weak anaerobic growth, suggesting that they facilitate low-salt doenjang fermentation. Strains D2-2 and D12-5 were not hemolytic, carried no toxin genes, and did not produce biogenic amines. These results suggest that strains D2-2 and D12-5 can serve as appropriate starter cultures for fermenting low-salt doenjang with high quality and safety.

• Journal of Applied Biological Chemistry
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• 제60권4호
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• pp.391-402
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• 2017

Lactic acid bacteria (LAB) are widely used as starter culture in food fermentation due to their harmless entity and health beneficial properties along with the ability to change texture, aroma, flavor and acidity of food products. In this study, five different LAB (FB003, FB058, FB077, FB081, and FB111) isolated from different Korean traditional fermented foods, assigned to Lactobacillus plantarum, Pediococcus pentosaceus, Weissella viridescens, Lactobacillus sakei, and Leuconostoc mesenteroides, respectively, on the basis of their physiological properties and 16S rRNA sequence analysis, to use as fermentation starter and check their ability to fasten the ripening time as well as the overall optimization in the fermentation condition. To check their suitability as starters, their safety, acid and bile tolerance, NaCl and temperature resistance, susceptibility to common antibiotics, and antimicrobial activities were determined. Squid jeotgal samples were prepared by adding $10^8CFU/g$ of each strain in different samples, which were then kept for fermentation at $4^{\circ}C$ and checked for their antioxidant activities at 0, 7, 15, and 21-day intervals. The samples fermented with FB003 and FB077 displayed the highest antioxidant activity. This study revealed two effective starter cultures (FB003, FB077) for squid jeotgal fermentation, which presented increased functionalities. The results of this study will lead to the development of novel industrial-scale production avenues for jeotgal preparation, and offer new insights into the prevention and control of chronic diseases.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1100-1108
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• 2009

Lactic acid bacteria (LAB) isolated from various fruits and vegetables were screened in order to determine appropriate fermentation starters for manufacturing functional fermented onion juice. From the initial screening test comprising more than 700 isolated LAB, 16 isolates were selected based on their acid production rate. Among the selected isolates, the fermentation broth of KC-007 exhibited the highest electron donating and nitrite scavenging activities, with values at pH 1.2 of 95.6 and 68.7%, respectively. From the overall results obtained in this study, we finally selected the bacterium KC-007 as a fermentation starter. This bacterium was identified and named as Pediococcus pentosaceus based on its morphological and physiological characteristics, carbon-utilization pattern (as assessed using an API 50CHL kit), and molecular genetic characteristics (as assessed using the nucleotide sequence of the 16S rRNA gene). The optimal temperature, pH, and starter inoculation concentration (v/v) required for growth of the isolated strain were $40^{\circ}C$, pH 4.0-6.0, and 2%(v/v), respectively.

• Journal of Microbiology and Biotechnology
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• 제29권4호
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• pp.527-537
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• 2019

Three types of meongge (Halocynthia roretzi) jeotgal (MJ) were prepared with 3 different types of salts (12%, w/v): purified salt (PS), solar salt aged for 3 years (SS), and bamboo salt that had been recrystalized 3 times (BS). One set of MJ was fermented with starters, Bacillus subtilis JS2 and Tetragenococcus halophilus BS1-37 (each 6 log CFU/g), and another set without starters for 42 days at $10^{\circ}C$. The LAB count of the SSMJ (non-starter) was highest at day 28 (2.30 log CFU/g). The pH of the PSMJ and SSMJ was 5.72-5.77 at day 0, and 5.40-5.50 at day 42. BSMJ showed higher pH and lower titratable acidities than other samples. Amino-type nitrogen (ANN) increased continuously, and SSMJ showed higher values than other samples from day 14. Bacterial species of non-starter MJ were examined by culture independent method. Clone libraries of 16S rRNA genes were constructed in Escherichia coli from total DNA from non-starter MJ samples at day 0, 14, and 28. Thirty clones per each sample were randomly selected and DNA sequences were analyzed. Variovorax sp., uncultured bacterium, and Acidovorax sp. were the most dominant group at day 0, 14, and 28, respectively. Lactobacillus sakei and Streptococcus sp. were the next dominant group in SSMJ at day 28. A Streptococcus sp. was detected from PSMJ at day 28. Sensory evaluation for MJ samples at day 28 showed that SSMJ got higher overall acceptability scores. These results showed that solar salt can cause desirable changes in the microbial community of fermented foods, thereby positively affecting their overall quality.

• Animal Bioscience
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• 제35권12호
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• pp.1881-1891
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• 2022

Objective: The present study aimed to quantify the effects of fermented soybean meal (FSBM) on broiler chickens' performance by employing a meta-analysis approach. Methods: A total of 16 studies were included in the database after being systematically selected using a PRISMA protocol. Hedges' g effect size was used to quantify pooled standardized mean difference (SMD) using random-effects models at 95% confidence intervals (95% CI). Publication bias among studies was computed with Egger's test and visualized using funnel plots. Results: Results indicated that dietary FSBM inclusion increased final body weight (BW) (SMD = 0.586, 95% CI: 0.221 to 0.951, p = 0.002) of broiler chickens, particularly in starter period (SMD = 0.691, 95% CL: 0.149 to 1.233, p = 0.013) while in the finisher period, the effect was weaker (SMD = 0.509, 95% CI: 0.015 to 1.004, p = 0.043). Average daily gain (ADG), feed intake (FI), and feed conversion ratio (FCR) were not affected with FSBM inclusion when compared to control. Subgroup analysis revealed that FI increased in starter period (SMD = 0.582, 95% CI: 0.037 to 1.128, p = 0.036). When considering types of microorganism as moderating variables in the subgroup analysis, we found that Aspergillus oryzae, mixed probiotics+bromelain protease, Bacillus subtilis, and Lactobacillus bacteria significantly increased ADG and FI (p<0.01). Additionally, either Bacillus subtilis+protease or Bacillus subtilis alone decreased FCR (p<0.001). However, meta-regression analysis showed that levels of FSBM inclusion had no effects on final BW (p = 0.502), ADG (p = 0.588), FI (p = 0.861), and FCR (p = 0.462). Conclusion: Substituting SBM in broiler chickens' diet with FSBM improved BW of broiler chickens, especially in the starter period whereas the effects on ADG, FI, and FCR were mostly dependent on microbial strains used for fermentation.

• 한국미생물·생명공학회지
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• 제42권1호
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• pp.1-10
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• 2014

식품발효용으로 사용하는 미생물은 오랜 기간의 사용이력에 근거하여 안전성에 대한 의문이 제기되지 않고 사용되어 왔다. 한편, 가공식품산업의 발달로 국제적인 식품 거래가 활발해지면서 수입국의 소비자와 정부당국은 식품에 첨가하는 미생물의 안전에 대해서 더욱 민감하게 반응하고 있다. 현재, 식품에 첨가하는 미생물에 대한 안전성 평가기준은 미국 Food and Drug Administration (FDA)가 사용하고 있는 Generally Recognized as Safe (GRAS)와 유럽연합 European Food Safety Agency (EFSA)의 Qualified Presumption of Safety (QPS)가 대표적으로 적용되고 있다. GRAS는 식품에 첨가하는 미생물 자체에 대한 안전성이 아닌 특정용도에서의 첨가에 따른 안전성을 의미하고, QPS는 식품에 첨가 가능한 미생물 단위(분류학적 단위, taxonomic unit)에 대한 안전성 평가이다. 우리나라에서는 전통발효식품의 상업적 생산이 증가하면서 종균 적용이 추진되고 있지만, 식품발효용종균에 대한 안전성 기준규격 없어 안전성 평가 없이 기능성만으로 종균 개발이 진행되고 있다. 전통발효식품의 세계화를 위해서는 향후 적용될 종균에 대한 기능적 측면뿐만 아니라 안전성의 확보가 필요하고, 식품용 미생물에 대한 안전성 평가 기준의 마련이 필요한 시점에 도달해 있다.

• 생명과학회지
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• 제13권1호
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• pp.59-66
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• 2003

Starter로 사용하기 위하여 $20^{\circ}C$에서 4일간 발효된 돌산 갓김치에서 미생물을 분리하였다. 이를 starter로 접종하여 $4^{\circ}C$와 $10^{\circ}C$에서 50일간 발효시키면서 발효특성, 항산화활성, ACE 저해활성을 조사하였다. 1 X $10^{10}$ CFU/mL의 접종농도에서 적숙기(pH 4.5)에 도달하는 시간이 $4^{\circ}C$에서는 최고 5.6배 이상, $10^{\circ}C$에서는 5배 단축되었다. 총균수는 starter 접종농도가 높을수록 발효초부터 높은 균수를 유지하였다. 항산화활성도 starter 접종농도가 높을수록 전반적으로 골게 나타났고, 1 X $10^{10}$ CFU/mL의 접종농도에서 $4^{\circ}C$와 $10^{\circ}C$ 각각 최대 67%와 75%를 나타내었다. 따라서 단위 시간당 세포의 생성율($lnX_{max}$/$t_{max}$)과 항산화활성($lnX_{max}$/$t_{max}$)은 비례관계를 가지며, 초기 접종농도가 높을수록 단위 시간 당 항산화활성이 높음을 알 수 있었다. ACE 저해활성도starter의 농도가 높을수록 ACE 저해활성도 놀게 나타났다. 즉, 1 X $10^{10}$ CFU/mL의 접종농도에서 $4^{\circ}C$에서는 52%, $10^{\circ}C$에서는 최대 76%를 나타내었다. 파라서 일정시간당 체포의 생성율($lnX_{max}$/$t_{max}$)이 증가할수록 ACE 저해율 ($P_{max}$/$t_{max}$)도 증가하였으며, 초기 접종농도가 높을수록 단 위 시간당 ACE 저해율이 높았다.

• Journal of Dairy Science and Biotechnology
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• 제36권3호
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• pp.178-185
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• 2018

Kefir, which originates in the Caucasian mountains, is a cultured milk beverage produced by a combination of acidic and alcoholic fermentation. Kefir products are commonly used as food vehicles to deliver health-promoting materials including kefran and lactic acid bacteria to consumers. The aim of this study was to develop a freeze-dried starter culture without yeast and assess the suitability of kefir-like dairy products for the growth of lactic acid bacteria and the acidification of milk. Pasteurized whole milk (SNF 8.5%) stored at $25^{\circ}C$ was aseptically inoculated with starter cultures (0.002% w/v); it was kept at $25^{\circ}C$ until the pH attained a value of 4.6. Ten grams of the kefir-like product sample was diluted with 90 mL of 0.15% peptone water diluent in a milk dilution bottle, followed by uniform mixing for 1 min. Viable cells of Lactobacillus species were enumerated on modified-MRS agar (pH 5.2), with incubation at $37^{\circ}C$ for 48 h. Viable cells of Lactococcus species were enumerated on M17-lactose agar, with incubation at $32^{\circ}C$ for 48 h. The pH attained a value of 4.6 after fermentation for 9 h 30 min (Starter 1), 9 h 45 min (Starter 2), and 12 h (Starter 3). The viable cell count of Lactobacillus sp. and Lactococcus sp. was initially $10^5{\sim}10^6CFU/g$; it increased significantly to $10^9CFU/g$ after 12 h of incubation. During the storage of the kefir-like products at $4^{\circ}C$ for 1 4 days, the total viable cell numbers were unchanged, but the pH decreased slightly. The consistency of the kefir products increased gradually during the storage. The organoleptic properties of the kefir products fermented using the new starter culture are more desirable than those of commercial kefir. These results suggest that the newly developed starter culture without yeast could be suitable for kefir fermentation.

• 동아시아식생활학회지
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• 제24권1호
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• pp.70-79
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• 2014

본 연구는 발효 소시지의 저장 기간 중 지질 산화를 억제하고, 항산화 활성이 우수하며, 유해 세균의 오염을 방지하기 위해 첨가되는 아질산염을 대체할 수 있는 천연 첨가제로써 자몽 추출물의 활용 가능성을 알아보고자 수행하였으며, 얻어진 결과는 다음과 같다. 자몽 추출물과 김치 유산균을 첨가하여 제조된 발효 소시지에서 우수한 지질 산화 및 유해 세균 억제 효과가 나타났으며, 저장 기간 7일차까지 아질산염과 아스코르빈산을 첨가한 처리구보다 우수한 결과를 나타내었다. 아질산염과 L. acidophilus를 혼합하여 제조된 처리구 A와 아질산염과 김치유산균을 혼합한 처리구 B, 아스코르빈산과 김치 유산균을 혼합한 처리구 C, 그리고 자몽 추출물과 김치 유산균을 혼합한 처리구 D의 제품 특성을 비교한 결과, pH는 처리구 D와 처리구 C에서 가장 낮게 나타났고, 유산균수는 자몽 추출물을 첨가한 처리구 D에서 가장 높았으며, 대장균 출현 억제효과는 아질산염과 L. acidophilus를 혼합한 처리구 A를 제외하고는 모두 시료 g당 100마리 이하로 나타났다. 육색 중 명도의 경우, 처리구 간의 유의차는 인정되지 않았으나, 적색도에서는 처리구 D와 아스코르빈산과 김치 유산균을 첨가한 처리구 C에서 유의적으로 높게 나타났으며, 황색도는 자몽 추출물을 첨가한 처리구 D에서 가장 낮게 나타났다. 조직감의 경우, 자몽 추출물을 첨가한 처리구 D가 다른 처리구에 비해 식감이 우수하였으며, 관능 평가에서는 아스코르빈산을 첨가한 처리구 C와 자몽 추출물이 첨가된 처리구 D에서 우수하게 나타나 자몽 추출물은 발효 소시지를 위한 천연 항산화제로써 활용 가능성이 매우 높았으며, 김치유산균인 L. brevis 또한 발효 과정 중 소시지의 산도를 낮추는데 효과적이며, 저장 기간 동안에도 지속적으로 발효를 유지시켜 유해 세균의 출현 및 성장을 억제하는데 매우 효과적임을 알 수 있었다.

• 한국식품영양과학회지
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• 제45권3호
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• pp.372-379
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• 2016

황칠 추출물에 미생물 균주를 달리 접종하여 제조한 황칠 발효액을 스타터로 첨가하여 제조한 된장의 발효 및 품질 특성을 조사하였다. 황칠 발효액 접종 시 총균수가 log 8 CFU/mL 이상으로 스타터로서 적용 가능성을 확인하였고, 발효 후에는 염도 8%, 10%의 경우 황칠 발효액을 첨가하여 제조한 된장의 총균수가 황칠 발효액을 첨가하지 않은 된장보다 낮았다. pH의 경우 염도 8%, 10% 된장이 12% 된장에 비하여 낮은 pH 값을 보였으며, 이와 반대로 산도는 12% 된장이 낮았다. 총유리아미노산 함량은 발효 후 2,162.5~2,872.2 mg/L로 발효 전보다 함량이 증가하였고 염도가 낮아질수록 총 유리아미노산 함량은 높았으며, Bacillus methylotrophicus S8을 이용하여 제조한 저염 된장(염도 8%, 10%)의 경우 같은 염도에서 다른 균주를 이용한 된장보다 glutamic acid 함량이 유의적으로 높았다. 황칠 발효액을 첨가하여 제조한 20일 숙성한 된장의 아미노태 질소는 413.4~700.7 mg%로 염도가 낮을수록 높았으며, 특히 B. methylotrophicus S8을 이용하여 제조한 된장에서 높은 함량을 보였다. 관능평가 결과 B. methylotrophicus S8과 Saccharomyces bayanus를 접종하여 제조한 된장에서 좋은 평가를 보였으며 8% 염도의 된장에서 B. methylotrophicus S8의 전체적 기호도가 가장 높게 평가되었다.