• Food Science and Biotechnology
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• 제15권6호
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• pp.844-850
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• 2006

This study was designed to compare various quality characteristics, such as nutrient composition and physicochemical and sensory properties of freeze-concentrated milk made by a newly developed continuous multi-stage process with those of evaporated milk. The freeze concentration process reduced the water content up to 73%. Most of the physicochemical properties of evaporated milk were different from raw milk; however the freeze-concentrated milk showed little difference from the raw milk. The thiobarbituric acid value and free fatty acid concentrations were significantly greater in the evaporated milk than in the freeze-concentrated milk. Several effects on sensory characteristics, such as off-taste, were significantly stronger in the evaporated milk. Overall, this study indicates that the newly developed freeze concentration technique results in improved physicochemical and sensory properties, and has little effect on most nutrient levels when compared with the evaporation process. Further research is necessary to further elucidate the chemical and sensory properties of freeze-concentrated milk.

• Food Science and Biotechnology
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• 제15권5호
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• pp.756-762
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• 2006

Freeze concentration of milk was carried out through the controlled recrystallization of ice in a multi-stage freeze concentrator. Rheological characteristics of ice slurries were analyzed to determine efficient concentration levels for the freeze concentration process. It was determined that efficient concentration level was 17% of total solids in the first and 27% in the second stage. Physicochemical properties were compared between freeze concentrated and evaporated milk. Freeze concentrated milk was more similar in color appearance to control milk than was evaporated milk. pH significantly decreased in evaporated milk than in freeze concentrated milk. pH of freeze concentrated milk resulted in similar value to control. These results indicated the advantages of freeze concentration as a non-thermal milk processing technology in terms of physicochemical properties. Consequently, we investigated the influence of ice recrystallization on the rheological characteristics of ice slurries and physicochemical properties of freeze concentrated milk.

• Asian-Australasian Journal of Animal Sciences
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• 제26권8호
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• pp.1197-1204
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• 2013

This study was carried out to investigate the physicochemical and sensory properties of milk with added powdered peanut sprout extract microcapsules (PPSEM) during the storage at $4^{\circ}C$ for 16 d. The size of PPSEM varies from 3 to $10{\mu}m$ as observed by the scanning electron microscopy (SEM). The pH values of all samples ranged from 6.8 to 6.6 during the storage. Release of resveratrol for 0.5 and 1% PPSEM addition was about $0.89{\mu}l/ml$ and TBARS value found to lower during storage of 16 d. The $a^*$ and $b^*$ color values of high concentrations (1.5, 2.0, 2.5 and 3.0%) of PPSEM-added milk samples were significantly increased during the storage (p<0.05). The sensory test revealed that the overall acceptability of PPSEM (0.5 and 1%) added milk sample were quite similar to that of control. Based on the data, it was concluded that the low concentrations of the microcapsules (0.5 and 1.0%, w/v) could be suitable to produce the microcapsule-supplemented milk without significant adverse effects on the physicochemical and sensory properties of milk.

• 한국식품조리과학회지
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• 제8권2호
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• pp.117-122
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• 1992

Tom coagulated with $CaCl_2$ was used to make high-Ca soy milk, named tofu milk. Physicochemical analysis of regular soy milk and tofu milk adjusted at various pH and/or heat-treated was carried out. Unheated and heat treated tofu milk kept stable conoldal state at pH 8. The solubility of soy milk was low at pH 4 but increased gradually at higher pH, while mat of tofu milk was almost unchanged between pH 4 and pH 7 but increased rapid1y above pH 8. At pH 8, the viscosity of tofu milk was almost the same as soy milk, while mat of heat-heated tofu milk was much higher man that of soy milk. Especially, steamed tofu milk seemed to be a thick paste unable to drink, but autoclaved tofu milk was suitable to drink. Phytic acid content of tofu milk was somewhat lower man mat of soy milk.

• 한국축산식품학회지
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• 제30권1호
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• pp.28-35
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• 2010

This study was designed to compare the physicochemical and nutritional properties between reconstituted milk samples made from freeze-dried milk powder (FDMP) and spray-dried milk powder (SDMP). Reconstituted milk (87%, wb) was made by combining FDMP or SDMP with water. In the color analysis, the $L^*$, $a^*$ and $b^*$ values of the reconstituted milk samples made from both powders were not significantly different from the control. The thiobarbituric acid values and short-chain free fatty acid concentrations were considerably greater in the reconstituted milk made from SDMP than in the milk made from FDMP. The quantities of water-soluble and fat-soluble vitamins in the reconstituted milk samples made from SDMP were significantly lower than those made from FDMP. Based on the findings obtained in the present study, the reconstituted milk made from FDMP appeared to be more resistant to lipid oxidation and exhibited little changes in the nutrients levels when compared with reconstituted milk made from SDMP.

• 한국축산식품학회지
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• 제33권1호
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• pp.9-15
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• 2013

A study was conducted to examine the physicochemical and sensory properties of milk supplemented with nanopowdered peanut sprouts (NPPS) at different concentrations (1, 3, 5, 7, and 9%, w/v) during the storage at $4^{\circ}C$ for 16 d. The size of NPPS ranged from 300-350 nm as observed by the particle size analyzer. The pH values of all samples ranged from 6.8 to 6.6 during the storage of 16 d. In color, the $L^*$ value of milk samples were not remarkably influenced by NPPS supplementation, whereas the $b^*$ and $a^*$ values significantly increased with the NPPS supplementation at all concentrations at 0 d storage, due to the original yellow color of NPPS powder (p<0.05). DPPH study revealed that higher antioxidant activity of milk supplement with higher concentrations of NPPS. TBARS value found to lower at the lower concentrations (1 and 3%, w/v) of NPPS supplementation. The sensory test revealed that the overall acceptability scores of NPPS supplemented milk samples (1 and 3%, w/v) were quite similar to control throughout the storage period of 16 d. Based on the data obtained from the present study, it was concluded that the concentrations (1 and 3%, w/v) of NPPS could be used to produce NPPS-supplemented milk without significant adverse effects on physicochemical and sensory properties, and enhance functional components from the supplementation.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2004년도 제34차 추계 국제 학술대회
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• pp.218-222
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• 2004

Low-fat (< 3%)/salt(< 1%) sausages were manufactured with two levels (1, 2%) of milk proteins(whey protein and sodium caseinate) to compensate for the textural problems due to reduced fat and salt(%). The addition of two levels of milk proteins into these meat products did not affect the most physicochemical and textural properties. As compared to regular-fat counterpart, higher expressible moisture of low-fat/salt sausages were observed. In addition, low-fat/salt sausages containing more than 2% of milk proteins reduced the textural hardness and gumminess, resulting in significantly lower these values, as compared to regular-fat counterparts. These results indicated that the low-fat/salt sausages were successfully manufactured with the addition of these milk proteins at the lower than 1% to improve the textural difference, however further research will be performed to improve the water holding capacity in these products.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2005년도 정기총회 및 제35차 춘계 학술 발표대회
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• pp.297-302
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• 2005

Physicochemical properties were compared between freeze concentrated and vacuum evaporated milk through colour, brix, viscosity, freezing point and pH measurement. Brix and viscosity in each concentrated milk significantly increased due to solute concentration(p<0.05), and there was not much difference between freeze concentrated and evaporative one. Brix results were numerically modeled with the logarithmic regression: Y=-33.460+18.4513 ${\cdot}$ ln(X), $R^2=0.9798$ and this model was fairly fit to predict the solute concentration in the middle of freeze concentration process. Freezing point significantly decreased according to concentration increment(p<0.05) and there was not the significant difference between freeze concentrated and evaporated one. Whereas, in colour and pH value, there were some differences between freeze concentrated and evaporative milk. Vacuum evaporated milk expressed higher discoloration comparing to freeze concentrated one. In pH values, evaporated milk showed the significantly decreased results comparing to freeze concentrated sample, whereas the pH value of freeze concentrated sample expressed the similar value to the reference milk.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1182-1193
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• 2021

The aims of this study were to develop a milk protein-based probiotic delivery system using a modified rennet-induced gelation method and to determine how the skim milk powder concentration level and pH, which can affect the rennet-induced intra- and inter-molecular association of milk proteins, affect the physicochemical properties of the probiotic delivery systems, such as the particle size, size distribution, encapsulation efficiency, and viability of probiotics in simulated gastrointestinal tract. To prepare a milk protein-based delivery system, skim milk powder was used as a source of milk proteins with various concentration levels from 3 to 10% (w/w) and rennet was added to skim milk solutions followed by adjustment of pH from 5.4 or 6.2. Lactobacillus rhamnosus GG was used as a probiotic culture. In confocal laser scanning microscopic images, globular particles with a size ranging from 10 ㎛ to 20 ㎛ were observed, indicating that milk protein-based probiotic delivery systems were successfully created. When the skim milk powder concentration was increased from 3 to 10% (w/w), the size of the delivery system was significantly (p < 0.05) increased from 27.5 to 44.4 ㎛, while a significant (p < 0.05) increase in size from 26.3 to 34.5 ㎛ was observed as the pH was increased from 5.4 to 6.4. An increase in skim milk powder concentration level and a decrease in pH led to a significant (p < 0.05) increase in the encapsulation efficiency of probiotics. The viability of probiotics in a simulated stomach condition was increased when probiotics were encapsulated in milk protein-based delivery systems. An increase in the skim milk powder concentration and a decrease in pH resulted in an increase in the viability of probiotics in simulated stomach conditions. It was concluded that the protein content by modulating skim milk powder concentration level and pH were the key manufacturing variables affecting the physicochemical properties of milk protein-based probiotic delivery systems.

• 한국축산식품학회지
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• 제30권4호
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• pp.661-668
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• 2010

This study was carried out to optimize microencapsulation conditions for Inonotus obliquus extract powder with mediumchain triacylglycerol (MCT) using response surface methodology (RSM), and to determine the possibility of adding encapsulated I. obliquus extract to milk toward improving the functionality of milk. and to investigate the effects of added encapsulated I. obliquus extract on the physicochemical and sensory properties of the product. The microencapsulation efficiency of I. obliquus extract powder was investigated with respect to three variables (ratios of core material to coating material, amounts of water added, and spray pressure) in RSM. The optimal conditions for microencapsulation of I. obliquus extract powder were obtained from the ratio of core material to coating material (2.92:10) and the amount of water added (0.5 mL); the spray pressure had an insignificant effect on the microencapsulation (p<0.05). Adding encapsulated I. obliquus extract into milk did not significantly affect either color (L, a and b values) or thiobarbituric acid (TBA) values. Sensory test revealed that there were significant improvements in brownish, herb flavor, and bitterness scores for encapsulated I. obliquus extract-added milk as compared with those for uncapsulated I. obliquus extract-added milk. Based on the data obtained from the present study, it is concluded that microcapsules of I. obliquus extract powder could be applicable to milk without remarkably adverse effects on physicochemical and sensory properties