• 한국식품저장유통학회지
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• 제24권7호
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• pp.1034-1042
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• 2017

저온 적응성 효모 SCY297의 종균 방법에 따른 생존율과 약주 제조시 양조 특성을 조사하였다. 동결건조, 송풍건조 및 액체 제형 방법으로 제조한 다음, 실온에서 장기 저장에 따른 효모의 생존율과 양조 특성을 비교하였다. 또한, 부형제로 skim milk, ${\alpha}$-lactose, trehalose를 5%씩 첨가하여 생존율과 양조특성에 미치는 영향을 조사하였다. 부형제가 첨가된 동결건조 및 액체 제형 SCY297 효모는 실온에서 15주까지 약 80% 이상의 생존율을 나타내었고, 송풍건조는 skim milk 첨가한 경우만 약 80% 이상 생존율을 나타내었다. 저장기간 및 제형화된 효모 SCY297로 약주를 발효하여 그 술덧을 분석한 결과, 동결건조 및 송풍건조된 SCY297는 무처리 SCY297보다 적정산도는 0.61, 아미노산도는 14.23 증가하였고, 알코올 함량은 5.07% 감소하였다. 액체 SCY297는 무처리 SCY297보다 pH 1.86, 아미노산도는 5.1 증가하였고, 알코올 함량은 2.9%로 감소량이 낮았다. 따라서 본 연구 결과, 종래의 고상형 방법보다 액상형 방법을 통한 종균화 가능성을 제시하였다.

• 농업과학연구
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• 제49권4호
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• pp.893-904
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• 2022

It is well documented that the fruit of the vitamin tree, which is rich in vitamins A, C, E, and K, shows anti-diabetic, antibacterial, immune regulation, anti-inflammatory, and anti-aging effects. In some countries including Europe it has been used to develop various functional foods. This study was conducted to elucidate the fermentation properties of fermented milk supplemented with vitamin tree (Hippophae rhamnoides L.) fruit powder. The pH, titratable acidity, number of viable cells, and viscosity of the yogurt made with vitamin tree fruit powder were found to be higher than those of the control group, as the amount of supplemented powder added became higher and the fermentation progressed. Production of lactic, malic, and acetic acids increased relative to that of the control as the amounts of supplemented powder were higher. It was found that the increase in the decomposition of lactose to glucose and galactose was proportional to the amount of supplemented powder added and the elapsed fermentation time. During storage for 15 days the quality of yogurt supplemented with vitamin tree fruit powder was within the proper range of fermented milk quality in terms of pH, titratable acidity, and number of lactic acid bacteria. The yoghurt manufactured with vitamin tree fruit powder has a similar quality to that of the control, and therefore, a new functional yoghurt providing health benefits could be developed.

• Journal of Dairy Science and Biotechnology
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• 제29권2호
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• pp.37-42
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• 2011

본 연구는 실시간으로 변동하는 유통조건하에서 온도데이터를 이용하여 우유의 품질을 예측하고 모니터링할 수 있는 적정 품질지표를 규명하고자 실시하였다. LTLT 살균우유와 UHT 살균우유를 0, 10, 20, 30 및 $40^{\circ}C$에서 저장하면서 pH, 산도, 색도, 미생물 및 관능특성 변화를 조사한 후 각 품질특성과 관능적 기호도와의 상관관계를 분석하였다. 우유의 저장온도에 따른 pH, 산도와 기호도와의 상관관계를 분석한 결과, 10, 20, 30 및 $40^{\circ}C$에서 유의적인 상관관계를 나타내었으며, 온도가 높을수록 높은 상관계수를 나타내었다(p<0.01). 미생물변화에서 일반세균수와 기호도와의 상관관계는 저온살균우유의 경우 0, 10, 20, 30 및 $40^{\circ}C$에서 각각 R=-0.81, R=-0.91, R=-0.96, R=-0.90 및 R=-0.99로 모든 온도조건에서 높은 상관계수를 보였으며, 초고온 살균우유에서도 $0^{\circ}C$를 제외한 모든 온도에서 유의적인 상관관계를 나타내었다(p<0.01). 색도는 고온저장에서만 유의성이 인정되었고, 그 외 온도에서는 기호도와 낮은 상관계수를 보이며 상관관계의 유의성이 인정되지 않았다. 따라서 모든 저장온도에서 관능적 기호도와 높은 상관관계를 나타낸 일반세균수의 변화를 우유의 유통 중 품질예측에 적용되는 품질지표로 선정하여 적용 하는 것이 적절한 것으로 판단되었다.

• 농업과학연구
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• 제37권3호
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• pp.387-392
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• 2010

This studies were carried out to assess fermentation properties of amylase activity and added rice yogurt of Enterococcus faecium KHM-11 isolated from Korean human milk. The amylase activity of Enterococcus faecium KHM-11 was above 23 units. Characterization of carbohydrate fermentation of Enterococcus faecium KHM-11 has D-ribose, D-lactose, L-arabinose and starch. Titratable acidity and viable count of lactic acid bacteria of 4% rice yogurt was higher compared to the 0%. Therefore we were discussed Enterococcus faecium KHM-11 is suitable microorganism for fermented milk added rice powder. Hydrolysates of sugars of fermented milk with 4% rice powder cultured Enterococcus faecium KHM-11 were analyzed by TLC and HPLC. Hydrolysates of lactose and galactose were revealed and hydrolysates of glucose was not revealed in results of TLC and HPLC.

• 한국식생활문화학회지
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• 제28권4호
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• pp.392-400
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• 2013

The purpose of this study was to determine the optimal amounts and mixing condition of skim milk powder (A), and roselle (B) for the production of yogurt prepared with roselle. The experiment was designed according to the central composite design for estimating the response surface method, which yielded ten experimental points, including two replicates for the skim milk powder and roselle. The physicochemical and mechanical analysis of each sample, including pH (P<0.001), titratable acidity (P<0.001), color (P<0.05), viscosity (P<0.001), showed significant differences. Antioxidant properties (total phenolic content, DPPH free radical scavenging activity) and viable cell counts of lactic acid were significantly different (P<0.05). The sensory measurements were significantly different in color, flavor, sourness, texture, and overall quality (P<0.05). The optimal formulation, calculated by numerical and graphical methods, was 7.82 g of skim milk powder and 2.09 g of roselle. From findings of this study, the roselle may be used in yogurt and can be applied for other food industries.

• 농업과학연구
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• 제48권2호
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• pp.273-281
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• 2021

These days, different types of yogurt are being manufactured by adding various starters and functional ingredients for health. The purpose of this study was to prepare yogurt added with rice followed by fermentation with two types of starters and to examine its attributes. Ten percent of skim milk powder and 0, 2.5, 5.0, 7.5, or 10% rice were mixed in water (w/v) and then inoculated with two types of starter: 1) Type A, Streptococcus thermophiles and Lactobacillus delbrueckii ssp. bulgaricus as starter; and 2) Type B, Streptococcus thermophiles, Lactobacillus acidophilus, and Bifidobacteium animalis ssp. lactis as starter. The pH of B type yogurt was lower (p < 0.05) than that of A type yogurt from 6 hours to 14 hours after fermentation. The number of microorganisms in all fermented milk showed maximum increases at 2 and 6 hours of fermentation (p < 0.05). The number of microorganisms in fermented milk peaked at 6 hours after fermentation and maintained this level thereafter. There was no effect of rice addition on microbial growth or acidity of the fermented milk. Sensory attributes of yogurt samples with and without added rice were not significantly different. This experiment showed that the production efficiency of yogurt with added rice was not different when two different types of starters were used to manufacture yogurt.

• Journal of Dairy Science and Biotechnology
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• 제31권1호
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• pp.21-33
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• 2013

The purpose of this study was to improve the production of Mozzarella cheese analogues manufactured using mixtures of soy milk and concentrated raw milk by performing ultrafiltration (UF) and to assess the quality of these cheeses during a 30-day storage period at $4^{\circ}C$, relative to that of Mozzarella cheese manufactured with the traditional method. The solid consistency of Mozzarella cheese analogue prepared from milk mixtures was lower than that of cheese manufactured from raw milk or soy milk and increased during storage, which is considered to be the result of decreasing water levels, as well as with increasing soy milk concentrations. In the Mozzarella cheese analogue generated using the milk mixtures, the fat content decreased with increase in the soy milk concentration, while it decreased during the storage period. Lactose levels were lowest in cheese composed of soy milk or raw milk and processed by UF, and decreased during storage in cheese produced using milk mixtures. In milk mixtures containing soy milk, the protein concentration increased with increasing amounts of raw milk and did not change during the storage period. The water-soluble nitrogen compound level was similar between cheeses and increased only slightly during storage. The amount of non-protein nitrogen compounds was higher in the cheese analogue than in the control cheese and tended to increase during storage. Analysis of the physicochemical traits of the Mozzarella cheese analogue yielded the following results: During storage, titratable acidity levels increased while pH tended to decrease. After analysis using electropherograms, it was classified as ${\alpha}$-, ${\beta}$-, or ${\kappa}$-casein. The results of rheometry tests showed that in the Mozzarella cheese analogue prepared from milk mixtures, with raw milk concentrated by UF, increases in concentration rate lead to lowered hardness, elasticity, cohesiveness, and brittleness. When cheese was produced from milk mixtures and concentrated by UF, meltability increased as the concentration rate increased, although to an extent that was less than that observed for the control cheese, and tended to increase during storage. Sensory evaluation showed that the analogue cheese was much better than the control cheese in terms of formation, appearance, and flavor.

• 동아시아식생활학회지
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• 제19권5호
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• pp.723-728
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• 2009

본 연구는 감귤 부산물 TMR 사료 급여가 젖소 원유의 품질에 미치는 영향을 검토하기 위하여 실시하였다. 감귤 부산물을 혼합하지 않은 TMR 사료를 급여한 원유를 T0, 그리고 감귤 부산물을 혼합한 TMR 사료를 급여한 원유를 T1이라 하였다. 젖소는 홀스타인종으로 제주도 소재 낙농 목장에서 사양 시험을 하였으며, 1회에 7 마리씩 3반복 실행하였다. T0 및 T1의 산유량은 각각 24.16 및 25.97 kg이고, 체세포수는 66만 및 44만5천 개로 감귤 부산물 급여에 의해 산유량이 증가하고 체세포수가 감소하였다. T0 및 T1 원유의 총균수는 각각 $2.05{\times}10^6$ 및 $1.97{\times}10^6$ CFU/mL로 유의적 차이가 없었다. T0 및 T1 원유의 비중은 각각 1.0335 및 1.0342로 비슷하고, 적정 산도는 각각 0.14% 및 0.14%로 같은 수준을 나타내었다. 원유의 유지방 함량은 T1이 4.03%로 낮고, 유단백, 유당, 무지유고형분 및 총 고형분 함량은 현저한 차이를 보이지 않았다. 원유의 휘발성 향기 성분은 감귤 부산물 급여에 의한 유의적 차이를 보이지 않았다. 원유의 항산화력은 감귤 부산물 TMR 사료 급여에 의해 향상되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1798-1807
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• 2002

This study was conducted to investigate lactobacillus salivarius subsp. salivarius having probiotic properties to be used as the health adjuncts with fermented milk products. Acid- and bile-tolerant lactobacillus salivarius subsp. salivarius was isolated with lactobacilli MRS broth from faeces of 80 healthy persons (infants, children and adults). It was used as a probiotic strain in fermented milk products. The pH of fermented milk decreased from pH 6.7 to 5.0 and titratable acidity increased from 0.3% to 1.0% by L. salivarius subsp. salivarius (isolation strain 20, 35, and 37), when incubated for 36 h at 37$^{\circ}C$. The number of viable cell counts of fermented milk was maximized at this incubation condition. The SDS-PAGE evidenced no significant change of casein but distinct changes of whey protein were observed by isolated L. salivarius subsp. salivarius for titratable acidity being incubated by 0.9-1.0% at 37$^{\circ}C$. All of the strains produced 83.43 to 131.96 mM of lactic acid and 5.39 to 26.85 mM of isobutyric acid in fermented products. The in vitro culture experiment was performed to evaluate ability to reduce cholesterol levels and antimicrobial activity in the growth medium. The selected L. salivarius subsp. salivarius reduced 23-38% of cholesterol content in lactobacilli MRS broth during bacterial growth for 24 h at 37$^{\circ}C$. All of the isolated L. salivarius subsp. salivarius had an excellent antibacterial activity with 15-25 mm of inhibition zone to E. coli KCTC1039, S. enteritidis KCCM3313, S. typhimurium M-15, and S. typhimurium KCCM40253 when its pH had not been adjusted. Also, all of the isolated L. salivarius subsp. salivarius had partial inhibition zone to E. coli KCTC1039, E. coli KCTC0115 and S. enteritidis KCCM3313 when it had been adjusted to pH 5.7. The selected strains were determined to have resistances of twelve antibiotic. Strains 27 and 35 among the L. salivarius subsp. salivarius showed the highest resistance to the antibiotics. These results indicated that some of the L. salivarius subsp. salivarius (strain 27 and 35) are considered as effective probiotic strains with a potential for industrial applications, but the further study is needed to establish their use as probiotics in vivo.

• 한국식품영양과학회지
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• 제34권10호
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• pp.1579-1585
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• 2005

본 연구에서는 순물의 막분리에 의하여 제조된 농축분말을 사용하여 요구르트를 제조하고 pH, 적정산도, 점도, 생균수, 향기성분, 관능성 등을 분석함으로써 기능성 식품소재로의 이용 가능성을 검토하였다. UF 분말 첨가 요구르트의 발효 24시간 후 pH와 적정산도는 모든 시료간에 차이가 없는 것으로 나타났다. 점도는 대조군보다 UF 분말 첨가군이 낮았고 색도를 측정한 결과 UF분말 첨가 요구르트의 L값과 a값은 대조군과 첨가군간에 유의적인 차이가 없었고 b값은 UF분말 첨가량이 증가함에 따라 높아져서 유의적인 차이를 보였다. 생균수는 18시간까지 급격한 증가를 보이다가 그 이후 완만히 증가하여 발효 24시간에는 12.6$\∼$14.3$\times$$10^{8}$ CFU/mL를 나타내었고 대조군보다 UF 분말 첨가군에서 생균수가 높게 측정되었다. 요구르트의 휘발성 향기 성분은 UF분말 첨가군에서 대조군보다 다양한 향미 성분이 검출되었다. 관능검 사결과 냄새와 조직감은 시료간에 차이가 없었고 신맛은 UF분말 첨가군이 대조군보다 높게 평가되었으며 전체적인 바람직성에서는 시료간에 유의적인 차이가 없었다. 이상의 결과로 볼 때 UF분말을 이용하여 첨가수준을 조절하고 제조방법을 다양화한다면 영양학적으로 우수한 기능성 요구르트로서 그 이용가치가 있을 것으로 기대된다.