• Food Science of Animal Resources
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• v.31 no.6
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• pp.907-913
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• 2011

Low-fat and full-fat Mozzarella cheeses were manufactured using ultraflterated-concentrated cow milk with a bacterial cell count of 100, 000 CFU/mL to study the properties of browning, oiling-off, stretchability, and meltability of the cheeses during 3 mon of refrigerated storage. The properties of browning, oiling-off, and stretchability of UF-Mozzarella cheese were affected by fat content, addition of starter and rennet (add 50, 65, and 80% compared with the control, respectively), and baking temperature (280, 300, and $320^{\circ}C$) (p<0.05). The browning and oiling-off scores increased with an increase in baking temperature and lengthen of storage time, but some undesirable results also occurred. The stretchability score improved with an increase in baking temperature, but the gradient decreased with the length of storage time (p<0.05). The meltability score was affected by fat content, concentration factor, and storage period (p<0.05). The result of this study demonstrated the applicability of UF-milk in making Mozzarella cheese with high quality and good palatability.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.213-218
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• 1985

As a way of improving the texture and flavor of soybean cheese, whey-say cheeses were made by coprecipitation of various mixtures of whey, whey powder, soy milk and soy protein powder, and mixed culture of str. lactis, str. cremoris and rennet were added, then the cheeses were cured at $15^{\circ}C$ for up to 10 weeks. Physicochemical characteristics of the cheese were investigated by analyzing pH, titratable acidity(TA), water soluble nitrogen, 10% TCA soluble nitrogen, amino acid composition, beany flavor, color and hardness. The pH of whey-soy cheeses during ripening changed from 5.3 to 4.2 after 5 or 6 weeks and maintained that value while that of soybean cheese maintained a higher pH value. TA of whey-soy milk cheeses was gradually increased to the value of 0.4-0.45 after 8 weeks, but that of soybean cheese reached only 0.2 after the same period. Water soluble and 10% TCA soluble-nitrogen increased steadily during ripening. Hardness of the whey-soy milk cheeses reached maximum after three weeks of ripening and greatest at those made from 3 : 1 mixture of whey and soy milk and that from soymilk. Color of the whey-soy milk chesses was lighter than that of soybean cheese. The bean flavor of soybean cheese was strong and persistent for the whole ripening period. Acid flavor was dominant in the whey-so milk cheese and masked the beany flavor partially.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.369-376
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• 2013

Milk is well known to be rich in some nutrients such as protein, calcium, phosphorus, and vitamins. In particular, absorption and bioavailability of calcium receive lots of attention because calcium is very little absorbed until it is changed to the ionized form in the intestine. In this study, concentration of the soluble calcium was determined in the commercial bovine milk products, which were processed by different heat-treatment methods for pasteurization. As for general constituents, lactose, fat, protein, and mineral were almost same in the liquid milk products by different processors. Ultrafiltration of the skimmed milk caused little change in the permeate as for lactose content but both fat and protein decreased. pH values ranges from 6.57-6.62 at room temperature and slightly increase after centrifugation, 10,000 g, 10 min. Rennet-coagulation activity was the lowest in the ultra high temperature (UHT-)milk compared to the low temperature long time (LTLT-) and high temperature short time (HTST-)milk products. Each bovine milk products contains 1056.5-1111.3 mg/kg of Ca. The content of sulfhydryl group was the lowest in raw milk compared to the commercial products tested. For the skimmed milks after ultrafiltration with a membrane (Mw cut-off, 3 Kd), soluble Ca in the raw milk was highest at 450.2 mg/kg, followed by LTLT-milk 336.4-345.1 mg/kg, HTST-milk 305.5-313.3 mg/kg, UHT-milk 370.3-380.2 mg/kg in the decreasing order. After secondary ultrafiltration with a membrane (Mw cut-off, 1 kD), total calcium in raw milk had a highest of 444.2 mg/kg, and those in the market milk products. As follow: UHT-milk, 371.3 to 378.2 mg/kg; LTLT-milk, 333.3 to 342.2 mg/kg; HTST-milk 301.9 to 311.2 mg/kg in a decreasing order.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.208-214
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• 1993

Ginseng-whey beverages were prepared with rennet whey, ginseng, sweetener, honey and Japanese apricot, inoculated with different strains of lactic acid bacteria or unfermented partly. The samples were stored at 4$^{\circ}C$ or 30$\pm$1$0^{\circ}C$ and then physicochemical and microbiological properties were investigated. The yield of whey was 78.8%. The pH-values reduced and acidities increased during the storage period. The contents of solid-substances, ash and lipid in ginseng-whey beverages were 7.90~8.20%, 0.62~0.66% and 0.16%, respectively. The protein contents of ginseng-whey beverages were 0.42~0.56% and the contents were not changed during the storage period. The lactose contents of fermented beverages were higher than those of unfermented beverages. During the storage period (1~5 weeks), the ranges of D(-) - and L(+)- lactic acid contents in fermented ginseng-whey beverages (17.3~156.1 mg/100g, 347.3~1894.2mg/100g) were higher than those of unfermented ginseng-whey beverages (6.2~82.8mg/100g, 7.1~885.5mg/100g). The contents of total saponin in unfermented sample and fermented sample (Lac. casei sub-sp. casei+Str. salivarius sub-sp. thermophilus) were increased during the storage period. But, those of the fermented sample(Lac. acidophilus+Lac. delbrueckii sub-sp. bulgaricus) were reduced. In the electrophoretic results of ginseng-whey beverages, an $\alpha$-lactalbumin and a $\beta$-lactoglobulin bands were shown apparently and there were no changes observed during the storage period. During the storage period (1~3 week) the coliform was not detected and total plate counts and psychrotrophs were increased according to the storage period.

• Journal of Dairy Science and Biotechnology
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• v.30 no.2
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• pp.93-109
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• 2012

This study was performed to investigate the effects of added whey protein concentrates (WPC) and whey powder (WP) on the quality and shelf life of Tofu, a traditional food in Korea. Combined whey powder and whey protein concentrates were obtained at drainage after the casein was separated by using rennet enzyme or acidification of milk. We manufactured whey Tofu and evaluated its nutritional quality by testing, the general composition for yield, moisture, pH, crude protein, crude fat, carbohydrate, rheology, sensory properties, and change during storage. 1. The general compositions of WPC and WP were as follows: (a) WPC: moisture, 5.9%; crude protein, 56.2%; crude fat, 0.1%; carbohydrate, 32.6%; ash, 5.2%; and pH 5.93 and (b) WP: moisture, 3.7%; crude protein, 13.2%; crude fat, 1.6%; carbohydrate, 74.4%; ash, 7.1%; and pH, 6.65. 2. The yield of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest (265%) at $13.3g/cm^2$, but with 4% addition WP was the lowest (184%) at $22.2g/cm^2$. 3. The moisture content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL = 6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest at 79.82% ($13.3g/cm^2$), but 4% was the lowest at 75.18% ($22.2g/cm^2$). 4. The pH of Tofu was as follows: (a) in WPC, the value was WPC 6% > WPC 4% > WPC 2% > control and $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 and (b) in WP, WP 4% > WP 2% > control. 5. The ash content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, there was no difference between 2% and 4% addition. 6. The crude protein content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, there was no difference between 2% and 4% addition. 7. The crude fat content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, values decreased with increasing pressed weight. 8. The carbohydrate content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, values increased with increasing pressed weight. 9. The rheology test results of Tofu were as follows: (a) in WPC, hardness and brittleness was highest with $CaCl_2$:GDL=8:2 and 6% added WPC. Cohesiveness was highest with $CaCl_2$:GDL=6:4 and 2% added WPC. Elasticity was the highest with $CaCl_2$:GDL=7:3 and the added WPC control. (b) in WP, hardness was the highest with $22.2g/cm^2$ and added WP control. Cohesiveness was the highest with $17.8g/cm^2$ and added WP 2%. Elasticity was the highest with $17.8g/cm^2$ and added WP 4%. Brittleness was the highest with $17.8g/cm^2$ and added WP control. 10. The sensory test results of Tofu were as follows: (a) in WPC, the texture, flavor, color, and smell were the highest with $CaCl_2$:GDL=6:4 and 6% added WPC. (b) in WP, the texture was the highest in the control with $22.2g/cm^2$. Flavor and smell were the highest in WP 2% and $22.2g/cm^2$. Color was the highest in WP 2% and $17.8g/cm^2$. 11. The quality change of Tofu during storage was as follows: (a) in WPC, after 60 h, all samples began to get spoiled and their color changed, and mold began to germinate. (b) in WP, the result was similar, but the rate of spoilage was more rapid than that in the control.