• 한국식품과학회지
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• 제16권2호
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• pp.143-148
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• 1984

본 연구에서는 SPC-yogurt에 첨가되는 여러가지 당(糖)과 발육촉진물이 L.acidophilus의 생육에 미치는 영향을 관찰하고, 제조된 yogurt의 flavor를 조사하였다. Soy milk를 SPC(단백질 4.2%)와 여러가지 당(糖) 및 발육촉진물질로 제조하였고 준비된 Soy milk 100ml를 적절히 가열살균후 24시간 배양된 유산균 2.5ml를 접종하고 $37^{\circ}C$에서 24시간 배양하였다. 유산출 생육의 정도는 생균수, 산도, pH로 판단하였다. 배양시간에 따른 유산균의 생육도를 측정한 실험으로부터 6시간까지가 log phase이고 30시간까지가 stationary phase인것으로 나타났다 본 실험에서 사용된 당(糖) 가운데 glucose와 fiuctose가 유산균에 의한 산생성에 현저한 효과를 보였으며. 그 적정농도는 가각 3%정도였다 첨가된 발육촉진물질가운데 yeast extract가 유산균에 의한 산의 생성을 가장 촉진시켰으며 그 적정 농도는 0.5% 정도였다 SPC의 농도가 증가함에 따라 제조된 soy yogurt의 산도가 다소 증가하였다.

• 한국식품영양과학회지
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• 제24권2호
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• pp.254-260
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• 1995

Yogurt base were prepared from milk added with skim milk powder or Aloe vera powder and femented with lactic acid bacteria(the single or mixed strain of Lactobacillus bulgaricus and Streptococcus thermophilus). The yogurt product were evaluated for acid production(pH, titratable acidity), number of viable cell, viscosity, sensory property and quality-keeping property. The composition of organic acid were also analyzed by HPLC. Addition of Aloe vera remarkably accelerated acid production, and titratable acidity of Aloe vera yogurts(1.293∼1.407%) after 24 hours incubation was higher than that of yogurts added with only skim milk powder(9.98∼1.110%). Yogurt fermented with the mixed strain of L. bulgaricus and Sc. thermophilus was more acidic than that of single strains. The propagation of lactic acid bacteria was stimulated by Aloe vera and the number of viable cell after 24 hours incubation were above 9.87log CFU/ml. Viscosity of Aloe vera yogurt(3,860∼4,300CPS) was higher than that of yogurt with only skim milk powder(2,402∼2,604CPS). The overall sensory score of Aloe vera yogurt femented by mixed strain was the best of tested yogurt. When yogurt with Aloe vera was kept at 5℃ for 15 day, it's quality-keeping property was relatively good. The major organic acid of Aloe vera yogurt was lactic acid and lactic acid content of yogurt increased by addition of Aloe vera powder. The citric acid content decreased wtih fermentation and malonic acid, pyroglutaric acid and α-ketoglutaric acid were analyzed out a little.

• 한국식품영양학회지
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• 제13권1호
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• pp.71-77
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• 2000

New type yogurt base were prepared from milk added with skim milk powder or purple sweet potato, and fermented by lactic acid bacteria (Streptococcus thermophilus and Bifidobacterium infantis, 1:1, v/v). The yogurt proudcts were evaluated for acid production(pH, titratiable acidity), number of viable cell, viscosity, sensory properties, and color value. The composition of some organic acids was also analyzed by GC. The acid production slightly decrerased by addition with purple sweet potato. There was no significant difference in viable cell counts between control (yogurt added with only skim milk powder) and yogurt added with purple sweet potato, and viable cell counts of all samples were above 9.08 log cfu/ml. Viscosity of yogurt added with purple sweet potato(36,800∼46,000 centipoise) was higher than that of yogurt added with only skim milk powder(32,200 centipoise). The overall sensory score of yogurt added with purple sweet potato(38.6%, dry base) was the best of tested yogurt. The major organic acid of yogurt added with purple sweet potato was lactic acid. its content was 0.997∼1.203%. malic acid, succinic acid, oxalic acid, and fumaric acid were analyzed out a little. Lightness and yellowness decreased by addition with purple sweet potato but redness increased. Total color difference($\Delta$E) with yogurt addition with purple sweet potato and only skim milk powder were very high(above 11.46).

• 한국식품조리과학회지
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• 제31권4호
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• pp.485-496
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• 2015

This study was carried out to establish the optimal conditions for curd yogurt using saccharified rice solution. A central composite design was applied to investigate the effects of pectin (2.8~8.4 g), skim milk (14~70 g) and oligosaccharide (28~84 g) ratio on the physicochemical and sensory characteristics of curd yogurt using saccharified rice solution. pH, total acidity, and color value, were analyzed and sensory evaluation was performed. The pH of curd yogurt decreased with decreasing pectin and oligosaccharide ratio. The addition of pectin had a significant effect on the viscosity while skim milk had a significant effect on the color value (a and b value). The results of sensory evaluation showed that, oligosaccharide and skim milk had significant effects on sweetness and sour taste. Oligosaccharide and skim milk masked the sour taste of curd yogurt. The optimum range of ingredients for curd yogurt using saccharified rice solution was predicted to be 4.27~4.90 g of pectin, 30.80~41.30 g of skim milk, and 28.00~36.10 g of oligosaccharide. Based on the overlapped results of physicochemical and sensory evaluation, the optimal amounts of pectin, skim milk and oligosaccharide were 4.59 g, 36.50 g and 32.05 g, respectively.

• Journal of Microbiology and Biotechnology
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• 제6권1호
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• pp.50-53
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• 1996

A cultured milk product was made by fennenting 10$\%$ reconstituted skim milk with Lactococcus lactis subsp. lactis TA29 and Saccharomyces exiguus SK2. L. lactis TA29 and S. exiguus SK2 grew up to 1.0 $\times 10^9\;and\;2.0 \times 10^6$ cfu/ml, respectively. After the fermentation 21$\%$ of lactose was hydrolyzed, pH was lowered to 4.2, and titratable acidity and alcohol concentration were increased to 0.96 and 0.023$\%$, respectively. When the fermented milk was stored at $4{\circ}C$ for 9 days, the viable cell counts for L. lactis TA29 and S. exiguus SK2 were $6.5 \times 10^5\;and\;1.6 \times 10^6$ cfu/rnl, respectively. The alcoholic fermented milk prepared in this experiment was more inhibitory against some pathogenic bacteria including C. perfringens than commercial yoghurt products tested.

• 한국축산식품학회지
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• 제28권4호
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• pp.431-436
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• 2008

The impact of storage on the neuroprotective effects against $A\beta$-induced cell death and physicochemical characteristics of milk fortified with BF-7 were investigated. The BF-7 milk exerted protection of neuronal cells SK-N-SH from amyloid beta ($A\beta$)-induced neuronal stress. Our results showed that incubation of the cell with pretreated BF-7 milk, significantly attenuated apoptotic stress by $A\beta$, considered in cell morphology and nucleus shape. The general compositions were maintained consistently in BF-7 fortified milk (BF-7 milk). The BF-7 did not make any disturbance on pH and titratable acidity. The color change was not detected, either. Also, any microorganism had not been detected with more than 7 days storage at $4^{\circ}C$. In sensory evaluation study. the average scores of each sensory attribute were quite similar with plain milk. In conclusion, our results strongly indicate that BF-7 characteristics are quite adequate to be included in milk and BF-7 milk is still working well on neuro-protection, result in enforcing our brain and delaying neurodegeneration.

• 한국식품영양학회지
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• 제26권1호
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• pp.146-149
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• 2013

This study was performed to identify the effect of lactic-fermentation of peanut milk on n-hexanal content. Changes in viable cell populations, pH and titratable acidity indicated that there was a synergistic interaction between Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus during fermentation. The analysis of headspace volatiles revealed that n-hexanal nearly disappeared due to fermentation. S. salivarius subsp. thermophilus was more effective than L. delbrueckii subsp. bulgaricus in reducing the n-hexanal content.

• Preventive Nutrition and Food Science
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• 제6권2호
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• pp.96-100
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• 2001

Mixtures prepared from whole milk with added skin milk powder(2.5%, w/v) and Angelica keiskei juice (1.5%, w/v) were fermented with lactic acid bacteria (single and mixed culture of Lactobacillus bulgaricus and Strpetococcus thermophilus) for 24 hours. The fermented mixtures (curd yogurt) were evaluated for acid production (pH and titratable acidity), cell numbers, viscosity, sensory property and keeping quality. Results indicated that the addition of Angelica keiskei stimulated the acid production by lactic acid bacteria. The number of viable cells reached 4.5~7.3$\times$10$^{9}$ CFU/mL for Angelica keiskei-added yogurts, while 3.3~5.1$\times$10$^{9}$ CFU/mL for control yogurts. Viscosity of Angelica keiskei-added yogurts was higher (3,609~3,854 centipoises) than that of control yogurts(3,346~3,700 centipoises). Of the microorganism tested, mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus was most effective in acid production. The overall sensory score showed that Angelica keiskei yogurt fermented with Streptococcus thermophilus was evaluated as good as control yogurt. When yogurts were stored at 4$^{\circ}C$ for 12 days, pH, titratable acidity and viable cells of lactic acid bacteria were not significantly changed(p<0.05).

• 한국축산식품학회지
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• 제42권1호
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• pp.46-60
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• 2022

In this study, angiotensin-I-converting enzyme inhibitory (ACEI) activity was evaluated in fermented goat milk fermented by lactic acid bacteria (LAB) from fermented foods and breast milk. Furthermore, the potential for ACEI peptides was identified in fermented goat milk with the highest ACEI activity. The proteolytic specificity of LAB was also evaluated. The 2% isolate was inoculated into reconstituted goat milk (11%, w/v), then incubated at 37℃ until pH 4.6 was reached. The supernatant produced by centrifugation was analyzed for ACEI activity and total peptide. Viable cell counts of LAB and titratable acidity were also evaluated after fermentation. Peptide identification was carried out using nano liquid chromatography mass spectrometry (LC-MS/MS), and potential as an ACEI peptide was carried out based on a literature review. The result revealed that ACEI activity was produced in all samples (20.44%-60.33%). Fermented goat milk of Lc. lactis ssp. lactis BD17 produced the highest ACEI activity (60.33%; IC₅₀ 0.297±0.10 mg/mL) after 48 h incubation, viable cell counts >8 Log CFU/mL, and peptide content of 4.037±0.27/mL. A total of 261 peptides were released, predominantly derived from casein (93%). The proteolytic specificity of Lc. lactis ssp. lactis BD17 through cleavage on the amino acid tyrosine, leucine, glutamic acid, and proline. A total of 21 peptides were identified as ACEI peptides. This study showed that one of the isolates from fermented food, namely Lc. lactis ssp. lactis BD17, has the potential as a starter culture for the production of fermented goat milk which has functional properties as a source of antihypertensive peptides.

• 한국식품과학회지
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• 제25권6호
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• pp.666-671
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• 1993

본 연구에서는 전유(全乳)에 고형분 함량(15%)을 증가시키기 위해 탈지분유 대신 고구마와 호박을 첨가하여 요구르트를 만들고, 젖산균의 산생성, 생균수 및 요구르트의 품질(관능성, 저장성)에 미치는 영향을 조사하였다. 산생성은 12시간까지 급격히 증가하였고 그 이후에는 완만히 증가하였으며 호박첨가구보다 고구마첨가시 높았다. 생균수은 24시간 발효 후 모든구에서 $6.4{\times}10^{9}cfu/ml$이상이였으며 접종 후 12시간만에 정상기에 도달하였다. 발효액 중의 유기산은 탈지분유를 첨가한 경우보다 고구마나 호박을 첨가할 때 총산에 대한 젖산 함량 비율이 감소하여 대조구는 83%, 고구마첨가구는 76%, 호박첨가구는 74%이었다. 관능검사 결과를 보면 고구마첨가 요구르트가 대조구보다 우수하였고 호박첨가요구르트가 가장 나빴다. 발효가 완료된 모든 요구르트의 저장성은 $5^{\circ}C$에서 15일간 산생성과 pH, 생균수에 거의 변화가 없어 매우 우수한 것으로 나타났다. 이상의 결과를 요약하면 고구마를 첨가하여 기호성이 높고, 식품 영양학적인 가치가 있는 새로운 형태의 요구르트제조가 가능하였다.