• Journal of Dairy Science and Biotechnology
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• v.26 no.1
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• pp.1-4
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• 2008

Melatonin is one of the functional hormones in the milk and found in all mammalian species. The primary motivation for the use of melatonin as a supplement is as a natural aid to better sleep. Melatonin contents in milk vary according to the naturally occurring factors such as seasons and milking times. As a number of studies indicate melatonin supplementation helps to reduce the age-related decline in hormone production and overall enhancement of health, the more detailed studies are required to know the nature of milk derived hormones and to clarify them as a functional value adaptation. The objectives of this study were to examine the change of melatonin content in bovine milk during different milking times at the two dairy farms and during dairy process including homogenization and pasteurization. Commercial dairy products including night time milking products(night milk) marketed in Japan were also investigated. Melatonin content was determined by radioimmunoassay using 125I. Individual milk was collected from lactating Holstein cows at Kyong-Ki province in Korea. At farm A, the melatonin contents milking at 4 a.m. was higher than those of 7 p.m. and 12 p.m.($6.90{\pm}3.55,\;2.01{\pm}1.47$ and $0.16{\pm}0.04pg/mL$, respectively). At farm B, the mean melatonin contents milked from 24:00 AM to 05:00 AM have shown the highest contents ($4.65{\pm}$0.72pg/mL), and milking samples of the rest time had very little or non-detection of melatonin contents. Melatonin contents of commercial night milk samples were about 5 times higher than those of other common milk products. These results suggested that melatonin might be heat-resistant and commercial dairy process might not affect its contents in the final products.

• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.58-63
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• 2007

Bifidobacteria are probiotic organisms that provide both flavor and health benefits when incorporated as live cultures into commercial dairy products. Because bifidobacteria are very sensitive to environmental conditions (acids, temperature, oxygen, bile salts, the presence of other cultures, etc.), their viability in human gastrointestinal tract is limited. The microencapsulation of bifidobacteria is a process to protect them against harsh environmental conditions, thereby increasing their viability while passing through human gastrointestinal tract. To confirm the survival rate of microencapsulated Bifidobacterium breve CBG-C2 in milk, their survival rate was compared with several kinds of free bifidobacteria and lactic acid bacteria in commercial yogurt products under simulated gastric and small intestinal conditions. Double-microencapsulation of the bacteria was employed to increase the survival rate during digestion. The outer layer was covered with starch and gelatin to endure gastric conditions, and the inner layer was composed of a hard oil for the upper small intestinal regions. Almost all microencapsulted bifidobacteria in the milk survived longer than the free bifidobacteria and lactic acid bacteria in the commericial yogurt products under the simulated gastric conditions. Numbers of surviving free bifidobacteria and lactic acid bacteria in the commercial products were significantly reduced, however, the viability of the microencapsulated bificobacteria in the milk remained quite stable under gastric and small intestine conditions over 3$\sim$6 hrs. Thus double-microencapsualtion of bifidobacteria in milk is a promising method for improving the survival of bifidobacteria during the digestive process.

• Journal of Dairy Science and Biotechnology
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• v.34 no.3
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• pp.199-202
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• 2016

Processing methods of heat treatment in milk has been developed to increase safety for the consumer by destroying pathogens that may be found in milk. Commercial pasteurization of milk in the market started in the late 1800s in Europe and in the early 1900s in the United States. In 1962, it became a requirement in Korea that all milk for sale should be treated by heat. Nowadays, heat treatment (pasteurization or sterilization) became mandatory for all milk products sold in all over the world. However, since 1987, there was a big debate about the heat-treatment of milk. Korea Society of Dairy Science and Technology (KSDST) complied the 10 scientific articles of milk heat-treatment into the book which titled "Effects of the heat-treatment on the nutritional quality of milk". Almost several hundred copies had been distributed at the symposium KSDST in 1989. Currently, no one was able to find these articles in anywhere including library etc. Thus, author decided to re-write that books in serials because these articles should be pass on their knowledge of milk science to the next generation of milk research.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.91-97
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• 1974

This paper was developed for production of the humanized milk, comprising similarly to the composition and characteristic of human milk. Humanized milk of superior quality can be made directly from the fresh raw milk mixed vegetable oil, corn syrup, whey powder, ${\beta}-lactose$, sugar, vitamin, ${\beta}-carotene$ and minerals showing formulation of the humanized milk at table 2. The improving effects of adding vegetable oil and corn syrup are both more reformed the chemical and physical properties of humanized milk. The former enhanced the essential fatty acid and energy source in this product, the latter has the most solving function in water and induced amount of emulsion and stabilizer. The products contain about 13% protein, 23% fat, 58.3% carbohydrate, 2% ash and ensue reasonably balance of essential amino acid, poly-unsaturated fatty acid for the requirement of infants and controlled component of the humanized milk such as human milk.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1347-1353
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• 2006

Effects of microencapsulated chitooligosaccharide addition in milk were evaluated by determination of the efficiency of microencapsulation, cholesterol removal, color, viscosity and sensory properties. Coating material was polyglycerol monostearate (PGMS) and the efficiency of microencapsulation was 88.08% at a 10:1 ratio of coating to core materials (w/w). When 0.5% of microencapsulated chitooligosaccharide was added into milk, the color values (L, a, and b) and viscosity were significantly different from those of noncapsulated chitooligosaccharide-added groups (p<0.05). The release of chitooligosaccharide from microcapsules was 7.6% in milk at $4^{\circ}C$ for 15-day storage. In both 0.5 and 1.5% microencapsulation addition, the scores of all sensory characteristics except for off-flavor were significantly different between encapsulated chitooligosaccharide and noncapsulated chitooligosaccharide-added groups during all periods of storage. The present study indicated that chitooligosaccharide microcapsules could be applicable into commercial milk with little adverse effects on physical and sensory properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.6
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• pp.391-396
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• 1990

Changes in electric resistance was measured to carry out the kinetic analysis of milk gellation upon addition of rennet. Using pasteurized milk and commercial rennin, kinetic properties were investigated during milk gellation in terms of initial hydrolysis and coagulation steps. Specially designed reactor with two platinum electrodes was used throughout the experiments. As a function of either milk concentrations or reaction temperatures, gel time exhibited directly proportional relations: on the contrary, gel time was inversely pro-portional to enzyme concentration. Activation energies for enzymatic degradation and cogulation were 16.3, 4.6 and 34, 8.6 Kcal/mol, repectively. This simple analytical method proved to be very effective to characterize the mechanism of milk gellation. Moreover, unlike other methods, this method reguired simple apparatus and short time of analysis.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.389-393
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• 2007

In this study, the levels of aflatoxin $M_1$ ($AFM_1$) in milk were determined by HPLC with derivatization method. Milk samples were purified using $C_{18}$ disposable cartridge followed by derivatization with trifluoroacetic acid and analysed using HPLC with fluorescence detection. The recoveries of AFM1 from milk samples added $AFM_1$ at a level of 0.025~0.1 ng/ml were 94.7~98.0% with detection limit of 0.009 ng/ml. The amounts of $AFM_1$ were determined below 0.05 ng/ml for all tested samples of commercial milk collected in 1999 and 2000.

• Food Science and Industry
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• v.53 no.3
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• pp.256-263
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• 2020

Milk pasteurization is used to destroy harmful bacteria present in the raw milk for improvement of the keeping quality of dairy products. It is generally carried out in dairy industries as the heating process of raw milk in properly designed and operated equipment to a specific temperature for a specified a specified period. However, thermal processing may cause quality changes in milk as well as significant nutritional losses. Hence, many researchers have started work to design alternative strategies to produce safer foods with minimal thermal treatments for pasteurization. Therefore, the present paper shows the current status of commercial pasteurization system of dairy products in korean industry and the research efforts carried out by researchers on novel milk pasteurization system that could be an alternative to traditional thermal processes for maintaining the freshness of dairy products.

• Human Ecology Research
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• v.51 no.4
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• pp.383-393
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• 2013

The purpose of this study is to investigate the infant feeding and weaning practices in multicultural families. We surveyed 159 married female immigrants in Jeonbuk province from April 2010 to April 2011. They are from Vietnam (49.7%), China (25.8%), Cambodia (8.8%), Japan (8.2%), and the Philippines (7.5%). The average rate of colostrum feeding of all the subjects was 91% and there were significant differences between nationalities (p<.05), family types (p<.01), and delivery methods (p<.001). 41.5% of those answered did breast feeding, while 49.1% combined breast and bottle feeding, and 9.4% did bottle feeding only. The reason for bottle feeding is either because they are unable to produce enough breast milk or because they think the formula is better than breast milk. Average period of breast feeding was 10.3 months. There were significant differences of breast feeding duration between maternal age (p<.05) and economic level (p<.001). The mean onset time of weaning was 7.8 months, and there were significant differences between nationalities (p<.05), family types (p<.05), and feeding methods (p<.05). There was no significant difference in methods of supplementary food preparation between nationalities, family types, jobs, and education levels. The mean onset time of commercial milk was 12.8 months, and there were significant differences between nationalities (p<.05), the duration of marriages (p<.05), education levels (p<.05) and feeding methods (p<.001).

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8_spc
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• pp.1233-1243
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• 2019

Asia hosts more than half of the world's 1 billion goats and is also where domestication of wild goats began. Goats, including dairy goats, are adapted to a wide variety of harsh environments and thus play key roles as providers of nutrition, food security and socio-economic status to their human owners in many low-income Asian countries. In many countries in Southeast and East Asia, medium and large scale commercial dairy goat farming can be profitable enterprises because of the high price of goat milk, and good demand due to its health and medicinal properties. In some Asian countries, dairy goats play important roles in non-commercial activities, including use as educational animals in elementary schools in Japan and show animals in Indonesia. Dairy goat farmers in Asia are faced with numerous challenges, such as a shortage of high producing animals adapted to the local environment, lack of quality feeds during a prolonged dry season, many diseases and difficulty getting their product to market, however, the increasing demand for goat milk in the newly developed and developed economies in Asia provides an optimistic future for dairy goat production in this region.