• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.183-191
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• 1990

Soy milk prepared from soy protein concentrate was added with each of four types of milk products. Acid production and growth of five species of lactic acid bacteria(LAB) in soy milk and sensory property of soy yogurt were investigated. Acid production by LAB increased in proportion to concentration of milk products added to soy milk. Among the four milk products tested, whey powder or skim milk powder stimulated acid production by LAB more than whole milk powder or modified milk powder. Stimulating effect by whey powder on acid production by LAB was greater than other milk products at low concentration. Acid production by LAB in soy milk added with glucose or milk products significantly increased during fermentation. Sensory property of soy yogurt added with whole milk powder or skim milk powder was better than that of reference (soy yogurt added with glucose) while sensory property of soy yogurt added with whey powder or modified milk powder was Inferior to that of reference.

• Food Science of Animal Resources
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• v.42 no.6
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• pp.915-927
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• 2022

Recently, protein-fortified milk powders are being widely consumed in Korea to prevent sarcopenia, and the demand for high-protein food powders is continuously increasing in the Korean market. However, spray-dried milk proteins have poor flowability and wettability owing to their fine particle sizes and high inter-particle cohesive forces. Fluidized bed agglomeration is widely used to improve the instant properties of food powders. This study investigated the effect of fluidized bed agglomeration on whey protein isolate (WPI)-fortified skim milk powder (SMP) at different SMP/WPI ratios. The fluidized bed process increased the particle size distribution, and agglomerated particles with grape-like structures were observed in the SEM images. As the size increased, the Carr index (CI) and Hausner ratio (HR) values of the agglomerated WPI-fortified SMP particles exhibited excellent flowability (CI: <15) and low cohesiveness (HR: <1.2). In addition, agglomerated WPI-fortified SMP particles exhibited the faster wetting time than the instant criterion (<20 s). As a result, the rheological and physical properties of the WPI-fortified SMP particles were effectively improved by fluidized bed agglomeration. However, the fluidized bed agglomeration process led to a slight change in the color properties. The CIE L^* decreased, and the CIE b^* increased because of the Maillard reaction. The apparent viscosity (η_a,10) and consistency index (K) values of the rehydrated solutions (60 g/180 mL water) increased with the increasing WPI ratio. These results may be useful for formulating protein-fortified milk powder with better instant properties.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.99-104
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• 1996

Carbohydrate-free caseinomacropeptide (CMP) was isolated from the sweet whey powder by a precipitation method using 12% trichloroacetic acid. The yield of carbohydrate-free CMP was 2.7 g from 100 g sweet whey powder. The electrophoretic pattern and the amino acid analysis of CMP showed that isolated CMP was quite pure, indicating the precipitation with 12% trichloroacetic acid was very effective for isolating carbohydrate-free CMP from the sweet whey powder. Trypsin, covalently immobilized on pore glass beads by carbodiimide (EDC) method, was 20mg per 1g glass beads. CMP was almost completely hydrolyzed by soluble trypsin in 24hr, but not by immobilized trypsin. The tryptic hydrolysates were fractionated on a Bio-Gel P 4 column $(1.5{\times}120\;cm)$and separated peptides were tested for their capacities to inhibit platelet aggregation using a aggregometer. The hydrolysate obtained from CMP after 24hr digestion by immobilized trypsin showed the highest activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.192-201
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• 1985

Two experiments, utilizing 204 broiler chicks of the Maniker strain, were conducted to study the effects of dried whey and chitin on the growth of chicks. In the first experiment, diets containing 5%, 10%, or 15% dried whey, or a control diet with no whey, were fed to chicks from 1 day to 4 weeks of age. There were no significant differences among the dietary groups, with respect to the rate of growth or protein or feed efficiency. In the second experiment, chicks were fed with diets containing no whey, 2% chitin, 20% dried whey, or 20% dried whey plus 2% chitin, from 1 day to 4 weeks of age. Adverse effects (diarrhea, crooked toes and enlarged cecum) were observed in the group fed 20% dried whey. The protein efficiency ratio (PER) and feed efficiency ratio (FER) tended to improve in the dietary groups with dried whey, as compared to the control group. No significant differences were observed in the total carcass nitrogen and lipid levels of dietary groups. But the chitin-supplemented diets tended to improve on the growth rate compared to the groups without chitin. The results of the two experiments suggest that the growing broiler chick can tolerate up to 15% dried whey in the diet, without any harmful effect on growth. Also, chitin may improve the poorer growth rate of chicks fed dried whey, but not all of the adverse effects of whey.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1315-1320
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• 2011

Whey protein (WP) is a mixture of proteins, and is of high nutritional values. WP has become an important source of functional ingredients in various health-promoting foods. In this study, size-exclusion chromatography (SEC) and asymmetrical flow field-flow fractionation (AsFlFFF) were used for separation and analysis of whey proteins. It was found that a lab-prepared WP from raw milk is mostly of ${\beta}$-lactoglobulin with small amount of higher molecular weight components, while a commercial whey protein isolate (WPI) powder contains relatively larger amount of components other than ${\beta}$-lactoglobulin, including IgG and protein aggregates. Results suggest that AsFlFFF provides higher resolution for the major whey proteins than SEC in their normal operation conditions. AsFlFFF could differentiate the BSA and Albumin, despite a small difference in their molecular weights, and also was able to separate much smaller amount of aggregates from monomers. It is noted that SEC was able to show the presence of low molecular weight components other than the major whey proteins in the WP samples, which AsFlFFF could not show, probably due to the partial loss of those low molecular weight species through the membrane.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1179-1188
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• 2018

This study aimed to investigate the combined effect of using natural calcium mixtures and various binding ingredients as replacers for synthetic phosphate in ground pork products. We performed seven treatments: control (0.3% phosphate blend), treatment 1 (0.5% natural calcium mixtures [NCM, which comprised 0.2% oyster shell calcium and 0.3% egg shell calcium powder] and 0.25% egg white powder), treatment 2 (0.5% NCM and 0.25% whey protein concentrate), treatment 3 (0.5% NCM and 0.25% concentrated soybean protein), treatment 4 (0.5% NCM and 0.25% isolated soybean protein), treatment 5 (0.5% NCM and 0.25% carrageenan), and treatment 6 (0.5% NCM and 0.25% collagen powder). All the treatment mixtures had higher pH and lower cooking loss than the control, which was treated with phosphate. We found that NCM and binding ingredients had no negative effects on the moisture content, lightness, and yellowness of the cooked ground pork products. Treatments 3 and 4 showed significantly lower CIE $a^*$ values than the control. Treatments 2 and 6 improved the textural properties of the products. In conclusion, the combination of NCM with whey protein concentrate or collagen powder could be suitable for producing phosphate-free meat products.

• Food Science of Animal Resources
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• v.40 no.2
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• pp.209-220
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• 2020

Milk fat globule membrane (MFGM) is a lipid carrier in mammals including humans that consists mainly of polar lipids, like phospholipids and glycolipids. In this study, a process to enrich polar lipids in commercial butter and whey powder, including polar lipids of MFGM, was developed. WPC (whey protein concentrate) 60 was selected as the most suitable raw material based on the yield, phospholipid, protein, and lactose content of the polar lipid fraction obtained by ethanol extraction of two WPC (WPC60 and WPC70) and two buttermilk (A and B). After fractionation under optimum conditions, the polar-lipid enriched fraction from WPC60 contained 38.56% phospholipids. The content of glycolipids, cerebroside, lactosylceramide, ganglioside GM3, ganglioside GD3, was 0.97%, 0.55%, 0.09%, and 0.14%, respectively. Rancimat results showed that the oxidation stability of fish oil increased with an increase in the polar-lipid fraction by more than 30 times. In addition, the secretion of IL-6 and TNF-α decreased in a concentration-dependent manner after treatment of RAW 264.7 cells with 0.1 to 100 ppm of the polar lipid fraction. In this study, polar lipid concentrates with antioxidant and anti-inflammatory activity, were prepared from milk processing by-products. The MFGM polar lipid concentrates made from by-products are not only additives for infants, but are also likely to be used as antioxidants in cooking oils and as active ingredients for functional foods.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.35-49
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• 2013

The purpose of this study was to develop Mozzarella cheese analogues by using dairy products in the form of WPC 34, WPC 80, whey protein, demineralized whey powder, and lactose powder along with soy milk. Soy milk was separately blended with 5% WPC 34 (A), WPC 80 (B), DWP (C), WP (D), and LP (E) and also with 10% WPC 34 (F), WPC 80 (G), DWP (H), WP (I), and LP (J). Blending of soy milk and whey products showed that increase in the proportions of whey products (WPC 34, WPC 80, DWP, WP, and LP) led to increase in the protein, lactose, and SNF levels of the admixture. A decrease in fat content was observed for all cheeses prepared from mixtures, relative to those for the control cheese. The nitrogen content within analogue samples was higher than that in the control cheese and increased with increase in the proportions of whey products within soy milk. Higher water soluble nitrogen levels were observed in cheese prepared from whey-product-blended soy milk than in the control cheese. The non-protein nitrogen level within the control Mozzarella cheese was significantly lower than that in the Mozzarella analogues, and, in the case of cheese analogues, it increased with increase in the proportion of whey products in soy milk. With regard to the physicochemical and sensory qualities of the Mozzarella cheese analogues and control cheese, the pH of all analogue samples, with the exception of the cheese prepared from group G, was lower than that of the control Mozzarella cheese. Rheological studies showed that the hardness of Mozzarella cheese analogues was lower than that of the control Mozzarella, while the elasticity, cohesiveness, and brittleness of the analogues was higher. The control sample had a higher meltability level than any of the Mozzarella analogues. Mozzarella cheese prepared with the traditional method had higher browning and stretching levels than all the cheese analogues, but a lower oiling-off level.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.372-377
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• 2014

This study was conducted to evaluate the effects of oyster shell calcium powder (OSCP) as a substitute for phosphates in curing agent, on the quality of restructured pork ham. Restructured pork ham was processed under six treatment conditions: T1 (no additives), T2 (0.3% sodium tripolyphosphate), T3 (1.5% NaCl+0.5% whey protein), T4 (1.5% NaCl+0.5% whey protein+0.15% OSCP), T5 (1.5% NaCl+0.5% whey protein+0.3% OSCP), and T6 (1.5% NaCl+0.5% whey protein+0.5% OSCP). Addition of OSCP significantly increased the ash content and pH of restructured pork ham (p<0.05), but did not affect the cooking loss and water holding capacity values of restructured pork ham. Addition of OSCP had no effect on Hunter a and b surface color values of restructured pork ham, but did decrease the Hunter L surface color value (p<0.05). The addition of 0.5% OSCP showed significantly higher chewiness and springiness values of restructured pork ham, compared with the addition of phosphates (p<0.05). In conclusion, the addition of OSCP combined with low NaCl and 0.5% whey protein can be considered a viable substitute for phosphates in the curing agent, when processing restructured pork ham.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1246-1252
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• 2018

This study was conducted to investigate the effects of the addition levels of a phosphate replacer blend in ground pork sausages. The phosphate replacer consisted of 0.2% oyster shell calcium powder, 0.3% egg shell calcium powder, and 0.25% whey protein concentrate. Depending on the presence or absence of synthetic phosphate and the addition level of phosphate replacer, the following products were processed: control (+) (0.3% phosphate), control (-) (non-phosphate), 20AL (20% replacer), 40AL (40% replacer), 60AL (60% replacer), 80AL (80% replacer), and 100AL (100% replacer). The pH values of pork sausages increased (p<0.05) with increasing addition level of the phosphate replacer. When more than 40% of the phosphate replacer was added to pork samples (40AL, 60AL, 80AL, and 100AL), cooking loss was significantly reduced compared to both the control (+) and control (-). However, no significant differences were observed in the moisture content and CIE $L^*$ values between the controls and the treatments with a phosphate replacer. The control (+) and 100AL treatment had the highest (p<0.05) hardness, but the samples with the phosphate replacer were not significantly different in cohesiveness and springiness from the control (+). As addition level increased, the gumminess and chewiness of the products with the phosphate replacer increased, which were lower than those of the control (+). Therefore, more than 40% of a phosphate replacer may possibly substitute synthetic phosphate to improve product yields in ground pork sausages, although further studies may be needed for improving the textural properties of the final products.