• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.75-78
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• 1974

An experiment has been carried out in order to analyze the main components of Korean Cattles' milk, and fractionate the milk protein by DEAE-cellulose column. The results obtained were summarized as follow. 1) The average values of specific gravity, pH and acidity of Korean Cattles milk which were negative in alcohol test were 1,036, 6.4 and 0.21, respectively. 2) The average values of total solids, solids-not-fat, protein, lactose and ash contents of Korean Cattles milk were 11.61%, 9.53%, 2.08%, 3.99%, 4.76% and 0.86%, respectively. 3) Distribution of casein, whey protein, N.P.N., protein precipitated in 12% TCA, lactoglobulin and lactalbumin contents of the milk were 3.07%, 1.13%, 0.10%, 4.06%, 0.34% and 0.66%, respectively. 4) Acid casein obtained from Korean Cattles milk was fractionated into four fractions on DEAE-cellulose column with 0.005M tris-citrate buffer containing 6M urea, pH 8.6, and the ratio of the fraction I, II, III and IV was 3.24%, 52.67%, 26.22% and 17.87%, respectively. 5) Whey protein obtained from Korean Cattles milk was also fractionated into four fractions on DEAE-cellulose column with 0.04M phosphate buffer, pH 5.8, and the ratio of the fraction I, II, III and IV was 41.74%, 10.17%, 1.50% and 46.59%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.886-897
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• 2014

The aim of the present study was to get a total physical and chemical characterization and comparison of the principal components in Bangladeshi buffalo (B), Holstein cross (HX), Indigenous cattle (IC) and Red Chittagong Cattle (RCC) milk. Protein and casein (CN) composition and type, casein micellar size (CMS), naturally occurring peptides, free amino acids, fat, milk fat globule size (MFGS), fatty acid composition, carbohydrates, total and individual minerals were analyzed. These components are related to technological and nutritional properties of milk. Consequently, they are important for the dairy industry and in the animal feeding and breeding strategies. Considerable variation in most of the principal components of milk were observed among the animals. The milk of RCC and IC contained higher protein, CN, ${\beta}$-CN, whey protein, lactose, total mineral and P. They were more or less similar in most of the all other components. The B milk was found higher in CN number, in the content of ${\alpha}_{s2}-$, ${\kappa}$-CN and ${\beta}$-lactalbumin, free amino acids, unsaturated fatty acids, Ca and Ca:P. The B milk was also lower in ${\beta}$-lactoglobulin content and had the largest CMS and MFGS. Proportion of CN to whey protein was lower in HX milk and this milk was found higher in ${\beta}$-lactoglobulin and naturally occuring peptides. Considering the results obtained including the ratio of ${\alpha}_{s1}-$, ${\alpha}_{s2}-$, ${\beta}$- and ${\kappa}$-CN, B and RCC milk showed best data both from nutritional and technological aspects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.32-39
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• 1986

A strain of Aspergillus niger CAD 1 which produces considerable amount of beta-galactosidase was selected from extracellular beta-galctaosidase producing fungi isolated from soil. Optimal conditions for the enzyme from Aspergillus niger CAD 1 were the growth in wheat bran supplemented with 0.5% skim milk powder at $30^{\circ}C$ for 72 hrs. The crude enzyme was purified 1,387 fold through DEAE-cellulosc and Sephadex G-100 chromatographr and its recovery was 6.2%, The optimal pH and temperature for the purified enzyme were pH 4.5 ana $45^{\circ}C$, respectively. The Km and Vmax on ONPG were $3.57{\times}10^3M$ and 33.0 unit/mg protein, whereas those on lacose were $83.3{\times}10^3M$and 15.33 unit/mg protein, respectively, The activation energy for the enzyme was 9,900 cal/mol and the enzyme had no metal ion requirement for its activity and stability. The hydrolysis of lactose in skim milk, 4.8% lactose solution and acidic whey were 65%, 70% and 78% after 10 hrs incubation at $45^{\circ}C$, when 182 units of the enzyme were used 50ml of the substrate solutions.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.55-67
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• 2012

We compared the general composition of Mozzarella cheese manufactured by the traditional method and by an ultrafiltration technique. The comparison of the general components between raw milk and the retentate of ultrafiltration (CF 2 and CF 3) demonstrated the following. The fat, protein, and non-fat solid contents of the retentate were higher than those of raw milk, but the lactose content was lower. The effect of 3 factors-fat content (0.5% and 3%), bacterial populations (30,000 CFU/mL and 100,000 CFU/mL), and ratio of added starter and rennet (50, 65, or 80)-on Mozzarella cheese made by the traditional method and made using the retentate of ultrafiltration (CF 2 and CF 3) were compared. Total solids (TS), fat, lactose, total nitrogen (TN), water soluble nitrogen (WSN), non-protein nitrogen (NPN), and salt (NaCl) were affected by fat content, bacterial population, and the ratio of starter and rennet added, but the ash content was not affected. During storage at $4^{\circ}C$ over a period of 3 months, the TS, WSN, NPN, and NaCl contents increased significantly (p<0.05), but fat, lactose, and TN contents decreased significantly (p<0.05), while ash contents remained constant. In whey, the protein, lactose, and solids not fat contents were higher in cheese made from ultrafiltration retentate than in traditional Mozzarella cheese. These results indicate that ultrafiltration can be applied to producing several Mozzarella-type cheeses in order to meet consumer needs.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.988-995
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• 2003

Physiological parameters were measured on six primiparous, non-pregnant Holstein cows prior to peak lactation over a 3-month summer season in southwestern Taiwan. The objectives were to characterize heat stress-induced change in functionality of mammary gland under natural climates of tropical summer and to establish physiological indices applicable to this environment in referring to this change. Environmental and physiological readings, milk and blood samples were taken at 15:00 h biweekly for totally five time points during the study. Climate readings showed that the afternoon humidex value reached the highest (53.5) around mid summer. Rectal temperature of cows taken simultaneously varied between $38.26^{\circ}C$ and $40.02^{\circ}C$ in parallel to humidex. Milk production declined drastically from 29.2 to 22.2 kg/d the first month entering summer but leveled up at end of the summer season suggesting effects exerted by heat stress rather than stages of lactation. Lactose content decreased linearly (p<0.05) with times in summer, from 4.69 to 4.38%. On the other hand, activity of N-acetylglucosaminidase (NAGase) in milk increased linearly to over two folds (p<0.05) during the same intervals. Elevations of fractional constituent of BSA in whey protein and serum cortisol level were also noticed in the course. Measurement of arteriovenous concentration (A-V) difference across the mammary gland demonstrated net uptake of glucose and net release of urea throughout the study period. The amount of urea released from mammary gland increased (p<0.05) progressively from 1.54 to 7.76 mg/dl during summer. It is concluded that gradual regression of mammary gland occurred along the humid tropical summer season. This regression is likely initiated through elevation of body temperature, which is irreversible above certain point. The increased release of urea from mammary gland during heat stress suggests its potential role as an early indicator of suboptimal mammary function.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.20 no.3
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• pp.167-177
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• 2017

Purpose: Breastfeeding is the best way to feed all infants, but not all infants can be (exclusively) breastfed. Cow's milk based infant formula is the second choice infant feeding. Methods: The safety of a new synbiotic infant formula, supplemented with Bifidobacterium lactis and fructo-oligosaccharides, with lactose and a whey/casein 60/40 protein ratio was tested in 280 infants during 3 months. Results: The median age of the infants at inclusion was 0.89 months. Weight evolution was in accordance with the World Health Organization growth charts for exclusive breastfed infants. The evolution of all anthropometric parameters (weight-for-length z score and body mass index-for-age z score) was within the normal range. The incidence of functional constipation (3.2%), daily regurgitation (10.9%), infantile crying and colic (10.5%) were all significantly lower than the reported median prevalence for a similar age according to literature (median value of 7.8% for functional constipation, 26.7% for regurgitation, 17.7% for infantile colic). Conclusion: The new synbiotic infant starter formula was safe, resulted in normal growth and was well tolerated. Functional gastro-intestinal manifestations (functional constipation, regurgitation and colic) were significantly lower than reported in literature. Synbiotics (Bifidobacterium lactis and fructo-oligosaccharides) in cow's milk based infant formula bring the second choice infant feeding, formula, closer to the golden standard, exclusive breastfeeding.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.75-83
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• 2013

Mare milk is gaining importance because of its nutritional characteristics and therapeutic properties, which enable its use as part of the diet of the elderly, convalescents, and newborn infants. This review describes the functional and bioactive components of mare milk, such as proteins, carbohydrates, and lipids, and the characteristics such as acidification and released free amino acids of fermented mare milk. The protein profile of mare milk differs from that of bovine milk but is similar to that of human milk. The salt and lactose content in mare's milk is similar to that in human milk, but mare's milk has a significantly lower content of fat. Whey protein concentration is higher and casein content is much lower in mare milk than in bovine milk. These health-promoting properties indicate that mare milk and its derivatives could become valuable foods for elderly consumers in the form of probiotic beverages. Protein allergies related to and the potential industrial applications of mare milk have also been discussed in comparison with those of bovine milk. Although mare milk has diverse advantages if used as a nutritional food and has positive effects on health, further studies are required to enable its use as a complete substitute for human milk or as a health food.

• Journal of the Korean Applied Science and Technology
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• v.27 no.2
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• pp.114-122
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• 2010

Hydroxy fatty acids have gained important attentions because of their special properties such as higher viscosity and reactivity compared to non-hydroxy fatty acids. The new bacterial isolate Pseudomonas aeruginosa (PR3) had been well studied to produce mono-, di-, and tri-hydroxy fatty acids from different unsaturated fatty acids. Of those hydroxy fatty acids, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) was produced with high yield from oleic acid by P. aeruginosa PR3. Mostly, the substrates used for the production of hydroxy fatty acid by microorganisms were free fatty acids or synthetic lipids. However, it is highly plausible to use vegetable oils containing oleic acid such as olive oil for DOD production by P. aeruginosa PR3. As a first step to address the utilization of olive oil as a substrate for DOD production, we tried to determine the effect of vessel type on DOD production from olive oil by P. aeruginosa PR3. Of two different flask types of normal flask and baffled-flask, baffled-flask was highly effective for DOD production with all the media tested. Maximum increase of productivity by baffled-flask represented 221% with the medium supplemented with whey powder instead of lactose. Results from this study demonstrated that vessel type and medium composition could be both significant factors for DOD production from olive oil by P. aeruginosa PR3.

• Journal of the Korean Society of Food Culture
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• v.31 no.5
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• pp.489-497
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• 2016

Kunrak, a type of Korea traditional cheese, is made using Tarak, a yogurt produced with makgeolli as the fermentation source. Kunrak is produced by removing whey from Tarak, followed by drying process for safe storage and consumption over a longer period. In this study, we produced kunrak based on the method described in "Imwonsibyukji". Prepared Kunrak was ripening for 96 hours at 20, 30, and $40^{\circ}C$. In order to study characteristics of Kunrak, physiochemical properties (pH, acidity, water contents) and contents of metabolites (organic acids, sugars, amino acids, and fatty acids) were analyzed. During ripening, water contents decreased. The main organic acids in Kunrak were citric acid and lactic acid, and the main free sugar was lactose. Main amino acids were glutamate and phenylalanine, and main fatty acid was saturated capric acid. At later ripening, all metabolites increased immediately after preparation. The sensory evaluation score of overall preference was highest for Kunrak, which was ripening at $40^{\circ}C$ for 96 hours. This study was aimed to assay metabolites of Kunrak under various ripening conditions. The results provide basic data to produce conditions for standardized manufacturing of Kunrak.

• Animal Bioscience
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• v.34 no.8
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• pp.1283-1289
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• 2021

Objective: The progestogen-associated endometrial protein (PAEP) gene encodes the main whey protein in milk, β-lactoglobulin. The aim of the study was to investigate polymorphism in the PAEP gene and its association with milk yield, composition, and quality. Methods: Test-day records for 782 dairy cows were analysed. A total of 10 single nucleotide polymorphisms (SNP) within the PAEP gene were investigated. The following parameters were recorded: milk yield (MY, kg/d), percent milk fat (%), protein (PP, %), dry matter (DMP, %) and lactose (LP, %), urea content (UC, mg/L) as well as natural logarithm for somatic cell count (LnSCC, ln). Effect on genomic estimated breeding values accuracy was evaluated with pedigree and single step model. Results: Results show that only three SNPs were polymorphic, creating 5 composite genotypes: P1 to P5. Differences in MY between composite genotypes were noted in the two tested herds. Cows with P5 composite genotypes were characterised by the highest PP and LnSCC and the lowest LP and UC (p<0.05). P4 was linked to an increased DMP and UC, while P3 to an increase in LP and decrease in PP and LnSCC. Both factors are important markers in herd management and have high influences on the herds economics. For 5 out of 7 traits the accuracy of prediction was improved by including the haplotype as a fixed effect. Conclusion: Presented results may suggest a new way to optimise breeding programmes and demonstrate the impact of using genomic data during that process.