• 한국식품과학회지
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• 제20권2호
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• pp.245-251
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• 1988

Thermolysin 을 Dowex MWA-1에 10% glutaraldehyde로 고정화하였으며, 이 고정화 thermolysin을 사용하여 연속적응유(連續的凝乳)를 행(行)하였다. Thermolysin의 고정화수율(固定化收率)은 25%이었다. 고정화 thermolysin은 1/200M $Ca^{++}\;ion$의 존재하에서 $60^{\circ}C$의 고온에서도 안정하였으며 이 온도에서의 half-life는 16일이었다. 원료 milk를 pH 7.0이 되도록 조정하여 $55^{\circ}C$로 유지된 고정화 thermolysin column을 통과 시 켜 분해시킨 후, Streptococcus cremoris를 접종하여 응유(凝乳)시켜 curd를 얻었으며, 이렇게 하므로써 미생물오염이 방지될 수 있었으며 연속적응유를 효과적으로 행할 수 있었다. 고정화 thermolysin을 사용하여 얻은 cheddar type의 cheese는 rennet을 사용한 전통적인 방법으로 만든 cheese 와 거의 비슷하였다.

• 한국식품과학회지
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• 제34권3호
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• pp.419-424
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• 2002

매실 착즙액과 매실 과육을 첨가한 호상요구르트를 제조하기 위하여 탈지분유에 S. thermophilus와 L. casei를 혼합한 균주와 S. thermophilus, L. acidophilus와 L. casei를 혼합한 균주를 접종하여 매실 착즙액이 젖산균의 생육에 미치는 영향 및 관능적 특성과 품질 특성을 조사하였다. 매실 착즙액의 첨가는 젖산균의 생육과 산생성을 약간 증가시켰다. 실험구 중 S. thermophilus, L. acidophilus와 L. casei의 혼합균주에 3% 매실 착즙액을 첨가한 실험구가 가장 많은 양의 젖산(1.23%)을 생성하였고, 가장 높은 생균수$(3.6{\times}10^{11}\;CFU/mL)$를 나타내었다. 관능검사 결과 매실 착즙액 3% 첨가 호상요구르트에 20%의 당에 절인 매실 과육을 첨가한 실험구의 선호도가 가장 좋은 것으로 평가되었다. 매실 첨가 호상 요구르트의 일반 성분은 대조구보다 유리지방산, 구연산이 많은 것으로 나타났고, 무지고형분은 시료 모두 $9.58{\sim}9.94%$ 함유되어 있어 호상요구르트의 규격에 부합하였다. 색도 측정 결과 명도(L) 값은 유의적 차이가 없었으나, 적색도(a)와 황색도(b)는 매실 첨가 호상요구르트가 유의적으로 높은 값을 나타내었다. 매실 첨가 호상요구르트의 물리적 특성을 조사하였을 때, 매실 착즙액 3%를 첨가하여 발효시킨 후 20%의 당에 절인 매실 과육을 첨가한 실험구가 매실 착즙액 3% 첨가 호상요구르트와 대조구에 비하여 hardness, adhesiveness, gumminess가 유의적으로 매우 높은 값을 나타내었다. 따라서 매실 첨가 호상요구르트는 기호성과 품질 특성이 우수하고 영양학적으로도 훌륭한 상품적 가치가 인정되는 새로운 기능성 요구르트로서의 가치가 있을 것으로 사료된다.

• Food Quality and Culture
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• 제1권1호
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• pp.22-26
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• 2007

This study was performed to determine the feasibility of developing a healthy yogurt using tofu whey concentrates separated by nanofiltration (NF). The curd yogurt was prepared from whole milk with added skim milk powder, in which the NF powder was substituted at 0, 6.25, 12.5, or 25% for the skim milk powder. The quality characteristics were evaluated for pH, titratable acidity, viscosity, color, and viable cell counts. There were no significant differences in pH or titratable acidity between the control (yogurt with added skim milk powder only) and the yogurts with added NF powder, after 24 hr of fermentation at $37^{\circ}C$. The apparent viscosities of the yogurts with added NF powder were higher ($3,197{\sim}3,574\;cps$) than that of the control yogurt (3,196 cps). Lightness decreased, while yellowness increased, as the amount of NF powder increased. Sensory evaluations showed that the NF powder could be substituted for the skim milk powder at 6.25% without lowering the yogurt quality.

• Asian-Australasian Journal of Animal Sciences
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• 제24권9호
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• pp.1227-1232
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• 2011

The objective of this study was to examine the effects of concentrates containing different levels of a vitamin-trace elements premix on milk yield and composition of dairy cows. The trial, which lasted 14 weeks, was conducted from January to March and used 45 multiparous Brown cows in the early phase of lactation. Cows (n = 15 per treatment) were randomly allocated to three dietary treatments: the first group (control, C-0) was fed pelleted concentrate containing background vitamins and trace elements that supplied 1.0 times cows' daily requirements; the second group were fed the same concentrate, but containing 2.5 g/kg of vitamin and trace mineral premix per kg of concentrate (C-2.5); the third group were fed the same concentrate, but containing 5 g/kg of vitamin and trace mineral premix per kg of concentrate (C-5). The daily ration included ad libitum chopped oat hay, and the cows also had 8 h/d grazing on a ryegrass (Lolium multiflorum) pasture. During the performance trial, cow milk yield was daily recorded and individual milk samples were analysed for milk composition and to determine milk renneting properties. Cows fed the intermediate premix level (C-2.5) in diet showed the highest fat-corrected milk production (p<0.05) compared to other groups. None of the milk quality parameters studied were influenced by dietary treatment, except for milk rheological parameters (rennet clotting time and curd firmness) that were positively improved in cows fed the C-2.5 diet (p<0.05). The findings from this study show that intermediate level of vitamin-trace elements premix in concentrate can be advantageously used in grazing dairy cows without negative effects on yield and quality of milk produced.

• 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.

• 한국식품과학회지
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• 제20권3호
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• pp.317-325
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• 1988

농축대두단백으로 만든 두유를 여러 가지 정도로 가열 처리한 후 젖산균 5종을 각각 접종하여 두유의 가열처리가 젖산균의 생육과 산생성 그리고 대두요구르트의 관능성과 커드의 침전에 미치는 영향을 관찰하였다. 먼저 산생성을 보면 표준시료(비가열(非加熱)시료)에 비하여 $60^{\circ}C-10$분 또는 그 이상의 가열로 모든 균주에서 산생성이 촉진되었으며 그 촉진의 정도는 대체로 가열의 정도가 높을수록 점차적으로 증가하여 Streptococcus lactis를 제외한 4균주의 산생성이 $121^{\circ}C-1$분에서 가장 높았다. 그러나 생균수는 가열 처리로 큰 변화가 없었다. 대두젖산균 음료의 관능성에 미치는 영향을 보면 $95^{\circ}C-30$분 시료의 관능 성은 표준시료보다 현저하게 우수하였으나 $121^{\circ}C-15$분 시료의 관능성은 표준시료보다 현저하게 저조하였다. 한편 두유의 가열처리로 대두젖산균 음료의 침전이 지연디는 경향을 보였으며 특히 $121^{\circ}C-15$분의 가여로 침전이 현저하게 지연되었다.

• 대한지역사회영양학회지
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• 제9권5호
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• pp.606-614
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• 2004

This study was conducted to investigate the attitude to various soy foods and to estimate dietary isoflavone intake among Korean adolescents. The survey was carried out by self-administered questionnaire with 800 middle and high school students residing in urban and rural areas and 714 questionnaires were collected: resulting in 89% response rate. The dietary isoflavone intake was estimated by food frequency questionnaire developed for rapid assessment of isoflavone intake. Soybean paste, soybean curd, soy milk, bean sprouts and dambuk were recognized as nutritious and healthy food in order. Dambuk got the lowest score in taste and flavor. Bean sprouts, soybean curd and soybean paste were recognized as familiar food in order. Stuffed rice in fried soybean curd got the highest score and Miso soup got the lowest in preference. More than 50% of the subjects consumed soybean paste stew/soup and soybean curd over twice per week and 12.3% of the subjects consumed soybean over once a day. The estimated daily intake of isoflavones ranged from 0 to 227 mg, and the mean daily isoflavone intake of the subjects was 28.1 mg (16.3 mg genistein and 12.0 mg daidzein) whereas the median value of isoflavone intake was 19.7 mg. There was statistically significant relationship among Kyung Gi Do, Chung cheung Do and Seoul residents in their intake of isoflavone. The highest monthly income group consumed isoflavone more than the other groups. These results suggest that Korean adolescent perceived the soybean dishes as high quality foods but they didn't take much because of difficulty to cook or less chance to eat. Nutrition education program is needed to enhance consuming soy foods for prevention of chronic diseases related to dietary isoflavone intake. More detailed information on easy cook method of soy food is also needed.

• Applied Biological Chemistry
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• 제51권4호
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• pp.251-257
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• 2008

Different types of milk products, such as kwacha golla, mawa, cheese, curd, and chocolate are popular in Bangladesh. However, the microbiological safety of these products is poorly understood. This study was performed to assess the microbiological quality of kwacha golla, a local milk product. Kwacha golla samples were collected from ten different areas of Rajshahi and Kushtia regions, and the quality of the each sample was assessed using various parameters including standard plate count, total coliform, fecal coliform, total fungi, and spore-forming bacteria, as well as food-borne microorganisms. Out of 300 samples, total coliform was detected at 56.66% (n= 300), exceeding the minimum allowable limit of 36.66%. Similarly, experiments were carried out with fungi and food-borne pathogens including Escherichia coli, Listeria monocytogenes, Salmonella sp., and Staphylococcus aureus. Results revealed 85.33, 53, and 49.33% of the samples were contaminated by fungi, E. coli, and L. monocytogenes, respectively. However, all samples showed no contaminations of Salmonella sp. and Staphylococcus sp. Therefore, this study could be helpful to the people of Bangladesh by providing information on the possibility of a major health problem caused by the consumption of kwacha golla.

• 한국식품조리과학회지
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• 제9권2호
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• pp.123-127
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• 1993

본 연구에서는 우유에 탈지분유 또는 4종의 곡류(쌀, 보리, 밀, 옥수수)를 각각 2%(W/V) 첨가하고 Lactobacillus acidophilus(KCTC 2182)로 발효하여 커드상의 요구르트를 만든 후, 곡류 첨가 우유에서 유산균의 최적 생육온도 및 생육과 산생성의 경시직인 변화를 조사하였다. 본 실험에서 사용한 L. acidophilus(KCTC 2182)의 생육온도는 39~$41^{\circ}C$가 적합하였다. L. acidophilus를 접종하여 30시간까지 발효하면서 적정산도와 pH, 생균수를 관찰하였는데, 발효시간이 경과함에 따라 산생성이 현저히 증가하였고 pH는 저하하였으며 생균수는 18시간 또는 24시간까지 현저히 증가하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.153.1-153.1
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• 2002