• 한국식품영양과학회지
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• 제21권1호
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• pp.60-63
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• 1992

본 실험은 yoghurt와 yoghurt culture에서의 ${\beta}-galactosidase$의 활성도를 측정하였다. Liquid medium에서 자란 yoghurt culture의 ${\beta}-galactosidase$의 활성도는 S. thermophilus가 Lactobacillus에 비해 $5{\sim}10$배 높은 것으로 나타났으며 제조 yoghurt를 저장온도에 따른 차이를 실험한 결과 냉장보관$(4^{\circ}C)$시 한달 정도까지는 효소활성도와 생균수를 보전함을 볼 수 있었으나 실온저장시는 5일 정도 밖에 효소활성도와 생균수를 유지하지 못했다. 실험을 통해 ${\beta}-galactosidase$ activity는 생균수와 비례함을, 특히 S. thermophilus의 생균수와 비례함을 알수 있었다. 시판 yoghurt와의 비교실험에서는 활성도와 생균수에 있어서 반정도의 수준도 못 미침을 알수 있었는데 이는 다음호에 계속될 여러 요인들에 기인함을 짐작케 한다.

• 한국식품영양학회지
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• 제6권3호
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• pp.208-210
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• 1993

In order to know the influences of heat treatment of yoghurt on pH, $\beta$-galactosidase and viable cells, yoghurt sample was made by general method with Lactobacillus bulgaricus and Streptococcus thermophilus, and the changes in pH, $\beta$-galactosidase-activity and viable cell-count were determined during heating at 55$^{\circ}C$ and 7$0^{\circ}C$. The pH of yoghurt was not changed when the yoghurt was heated at 7$0^{\circ}C$, but at 55$^{\circ}C$ it decreased slightly. The stability of $\beta$-galactosidase was not affected markedly by heat treatment at 55$^{\circ}C$, but was rapidly inactivated at 7$0^{\circ}C$. The heat treatment of yoghurt at 55$^{\circ}C$ had the halb of viable cell in 1 hour, but the heat treatment at 7$0^{\circ}C$ had considerable effect on viable cell in 5 minutes.

• 한국축산식품학회지
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• 제18권1호
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• pp.35-41
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• 1998

The objective of this study was to examine the changes of physical properties by additions of different kinds of stabilizers milk proteins concentration, when stored at 4$^{\circ}C$ or 20$^{\circ}C$ for yoghurt. the results were summarized as follows: 1. Addition of 2% carboxyl methyl cellulose and carrageenan, gelation 0.4%, pectin and starch 0.6%, and carrageenan & pectin 0.8% in the manufacture of yoghurt increased the viscosity, water-holding capacity and protein hydration of yoghurt. 2. Addition of 3% skim milk powder, Ca-caseinate or Na-caseinate 0.6% increased the viscosity, water-holding capacity and protein hydration of yoghurt. 3. Twenty five percent of evaporation of milk promoted to build up the optimal structure of the micelles of yoghurt and improved viscosity, water-holding capacity and protein hydration of yoghurt. 4. Addition of stabilizers to yoghurt showed an increase of viscosity, water-holding capacity and protein hydration when compared with non-addition of stabilizers to yoghurt at 4$^{\circ}C$, 20$^{\circ}C$ storage for 12hrs, 96hrs followed by the decrease of it.

• 농업과학연구
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• 제23권2호
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• pp.219-226
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• 1996

한국인의 기호에 맞으며 약리적인 효능을 가지고 있는 인삼을 인삼 extract, 백삼분 및 미삼분 형태로 요구르트 제조시에 첨가하여 요구르트의 산생성도, 유산균수, 제품의 점도, 관능검사 및 보존성 등을 시험한 결과는 다음과 같다. 1. 인삼 extract, 백삼분 및 미삼분을 첨가한 액상 요구르트의 시험제조 결과 산도에 있어서는 무첨가구의 0.76%에 비하여 첨가구 특히 미삼첨가구가 1.15%로서 가장 높았다. 2. 유산균수는 무첨가구의 $1.5{\times}10^8/m{\ell}$에 비하여 첨가구가 더 증식되었고 특히 미삼첨가구가 $4.3{\times}10^8/m{\ell}$로서 가장 높았다. 3. 제품의 점도에 있어서는 무첨가구에 비하여 인삼첨가구 특히 백삼첨가구가 높았다. 4. 액상요구르트의 관능검사 결과 무첨가구에 비하여 맛, 향취 및 전체적인 기호도에서 미삼이 가장 높았다. 5. 요구르트 제품의 $5^{\circ}C$, 10일간 보존시험에서 pH, 산도 및 유산균수는 큰 변화가 없었다.

• 농업과학연구
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• 제26권1호
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• pp.31-38
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• 1999

한국인의 기호에 맞으며 약리적인 효능을 가지고 있는 인삼을 인삼 extract, 백삼분 및 미삼분의 형태로 요구르트 제조시에 첨가하고 제품의 산생성도, 유산균수, 점도, 관능검사 및 보존성 등을 시험한 결과는 다음과 같다. 1. 인삼 extract, 백삼분 및 미삼분을 첨가한 호상 요구르트의 시험제조 결과 산도는 무첨가구의 0.95%에 비하여 인삼첨가구 특히 미삼 첨가구가 1.13%로서 가장 높았다. 2. 유산균수에 있어서는 무첨가구의 $6.5{\times}10^8/ml$에 비하여 첨가구 특히 미삼첨가구가 $9.8{\times}10^8/ml$로서 가장 높았다. 3. 제품의 점성은 무첨가구에 비하여 첨가구 특히 백삼첨가구가 가장 높았다. 4. 제품의 관능검사 결과 맛과 향취에 있어서는 인삼첨가구가 우수하였고 조직에 있어서는 무첨가구가 우수하였으며 전체적인 기호도에 있어서는 미삼첨가구가 우수하였다. 5. 제품의 보존시험에 있어서는 $5^{\circ}C$, 10일간 보존에서 pH, 산도 및 유산균수의 변화가 크게 나타나지 않았다.

• 한국식품영양학회지
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• 제18권3호
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• pp.200-206
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• 2005

비파를 첨가한 stirred yoghurt를 제조하기 위하여 비파 착즙액 $15\%$를 Skim milk에 첨가하여 Streptococcus thermophilus 와 Lactobacillus acidophilus 혼합균주로 발효시킨 발효유에 비파 과육 첨가량 $(5\%,\;10\%,\;15\%,\;w/v)$과 올리고당 첨가량 $(10\%,\;15\%,\;20\%,\;25\%,\;w/v)$을 달리하여 제조한 stirred yoghurt의 품질 특성을 조사하였다. 관능검사 결과에서는 비파 과육 $15\%$와 올리고당 $20\%$를 첨가하였을 때 단맛, 신맛과 전체적인 기호도에서 가장 좋게 평가되었다. 색도 측정 결과 비파 과육 $15\%$ stirred yoghurt에 올리고당의 첨가량이 증가할수록 명도(L값)와 적색도(a값)는 감소하였고 황색도(b값)는 증가하였다. Texture 특성은 $15\%$ 비파 과육 첨가 stirred yoghurt에 올리고당 $20\%$ 첨가시 견고성(hardness), 탄성(springiness), 응집성(cohesiveness), 껌성(gumminess)과 탄력성(resilience)등에서 가장 높게 나타났다. 따라서 $15\%$비파 착즙액 첨가 발효유에 $15\%$비파 과육과 $20\%$ 올리고당의 첨가가 비파 첨가 stirred yoghurt 제조를 위해 가장 적합한 것으로 사료되었다

• Journal of Animal Science and Technology
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• 제46권1호
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• pp.69-76
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• 2004

홍화씨 yoghurt가 골다공증에 미치는 영향을 조사하기 위하여 sham-operation되어 6주간 정상식이한 군을 대조구로 하였고, 난소 절제하여 6주간 저칼슘식이한 군을 정상식이군(G I), yoghurt를 첨가하여 사육한 군(G II) 및 1%${\sim}$4%홍화씨yoghurt를 첨가하여 사육한 군(GIII${\sim}$GVI)으로 구분하여 실험식이를 급여하였다. 사료섭취량, 체중 증가량 및 사료효율을 알아보았고, 왼쪽 대퇴골의 무게, 밀도, 길이, 강도, 회분 및 무기질 함량을 조사하였다. 또한 오른쪽 대퇴골의 조직을 SEM으로 관찰하였다. 사료섭취량은 대구조와 실험구간 유의적인 차이는 없었다. 사료효율 및 체중 증가량은 홍화씨 yoghurt 식이구가 유의적으로(P　< 0.05) 높았으며, 특히 GV와 GVI구가 높게 나타났다. 왼쪽 대퇴골의 밀도, 강도, 회분 및 미네랄 함량은 대조구와 G I간에 유사한 경향을 나타내었고, 홍화씨 첨가수준이 높을수록 유의적으로 높게 나타났다. 반면 무게와 길이는 전 실험구에 있어서 거의 일정하게 나타났다. 전자현미경으로 측정한 결과 4% 홍화씨 yoghurt 식이구(GVI)가 가장 골다공증 치유효과가 높은 것으로 나타났다. 이상의 결과 홍화씨 yoghurt 식이가 난소 절제 및 저칼슘식이를 한 rat의 골다공증에 미치는 효과에 있어서 정상식이 및 yoghurt 식이구보다 홍화씨 yoghurt 식이구가 높은 치유효과를 보였으며 가장 우수한 것으로 나타났다.

• 한국축산식품학회지
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• 제20권1호
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• pp.64-71
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• 2000

The volatile flavour compounds such as acetaldehyde, acetone, ethanol, diacetyl and acetoin were detected by gas chromatography in adlay yoghurt during fermentation and storage period at 4 $pm$1$^{circ}C$, but acetoin was trace. The contents of acetaldehyde of adlay yoghurt showed maximum immediately after fermentation and decreased significantly(P<0.05) with storage period and were in order of adlay yoghurt fermented with YC-380, ABT-D and ABT-4. The contents of acetone were shown similar trend to acetaldehyde and those of adlay yoghurt fermented with YC-380, ABT-4 and ABT-D, decreased rapidly from 6 days, 9 days and 12 days of storage, respectively. The contents of ethanol increased during the storage period and those were significant differences(p<0.05) between 6 days and 9 days of storage period in control and treatments. The contents of diacetyl were detected in control and treatments at 9 days of storage and increased slightly during the storage period. The contents of volatile flavour compounds of T1 showed similar to that of control and slightly high compared to those of treatments, and decreased gradually with increasing the level of addition of adlay in treatments. The taste, flavour and texture of T1 immediately after fermentation and during the storage period at 4$\pm$1$^{\circ}C$ were slightly higher than those of control and treatments. The scores of sensory evaluation of treatments except T1 were lowered significantly(p<0.05) with increasing level of addition of adlay. Adlay yoghurt fermented with YC-380 and ABT-4 and ABT-D were superior to both of taste and flavour, and texture, respectively. From the results mentioned above, the addition of taste and flavour, and texture, respectively. From the results mentioned above, the addition of adlay at 1% (w/v) level in skim milk substrate were suitable for quality of adlay yoghurt such as volatile flavour compounds and sensory property.

• 한국축산식품학회지
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• 제20권1호
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• pp.21-29
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• 2000

This study was carried out to investigate the fermentation characteristics and storage of set-type yoghurt added mugwort extracts(AME) such as pH, growth of lactic acid bacteria, number of viable cells, viscosity, and sensory characteristics during 24 hours fermentation and 15 days storage. Addition of mugwort extracts was grown rapidly of lactic acid bacteria rather than that of control and also 4 or 8% AME groups were grown similar to control. The drop of AME pH of broth was less compared with control during incubation of lactic acid bacteria. The growth of lactic acid bacteria during incubation of AME yoghurt was not different of viable cell count between AME group and control in beginning time, but the viable cell count of AME groups were increased depended opon addition quantity of AME in ending time. Addition of mugwort extracts was not affect on pH change during yoghurt fermentation and increased a lactic acid bacteria number as well as no effect of yoghurt fermentation in ending time. The viscosity of yoghurt was almost not changed 3 hours after yoghurt mix and increased rapidly 6 hours after yoghurt mix. Although control and 0.5% AME group showed maximum viscosity at 18 hours of fermentation, 1 and 2% AME group showed linear increase until 24 hours of fermentation. Mugwort did not affect pH and viable cel number of lactic acid bacteria during 15 days storage 24 hours after fermentation. Sensory evaluation of the AME yoghurt showed that flavour, texture and acid taste were not affected by addition of mugwort. However, the appearance and taste were dropped by addition of mugwort.

• 한국식생활문화학회지
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• 제25권1호
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• pp.76-81
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• 2010

This study was conducted to evaluate the influence of Lactobacillus bulgaricus and/or Sterptococcus thermophilus on the fermentation of yoghurt containing 5% (w/v) buckwheat sprouts. The results revealed that after 12 hours of fermentation the appropriate pH, titratable acidity and number of viable cells were attained. At that time, the rutin content of the buckwheat sprout-added yoghurt prepared by the mixed culture method was not changed, but the quercetin content increased greatly. Conversely, the rutin content of yoghurt that only contained Streptococcus thermophilus was decreased while the quercetin content was increased. The total phenol contents as well as the DPPH radical scavenging activities of both the mixed culture and Streptococcus thermophilus yoghurt did not differ significantly. Taken together, the results revealed that the use of a mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus during the preparation of buchwheat sprout-added yoghurt was desirable due to the decrease in pH and increase in titratable acidity and viable cells that occurred after 12 hr of fermentation. Moreover, phytochemicals in buckwheat sprouts such as rutin, quercetin and phenol compounds were comparatively increased during fermentation and influenced the antioxidant activity in buckwheat sprout-added yoghurt.