• Journal of Dairy Science and Biotechnology
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• v.19 no.1
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• pp.13-21
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• 2001

Milk can be regarded as a complete food, containing protein, fat, lactose, vitamins and minerals. Milk is heated for a variety of reasons. The main reasons are: to remove pathogenic organisms; to increase shelf-life. But, when milk is heated, many changes take place: denaturation of whey proteins and interaction with casein, Maillard browning, losses of vitamin and minerals. The addition of a additive and milk powder to flavor and taste may cause undesirable change of quality during heating milk. The reconstituted milk is the milk product resulting from the addition of water to the dried or condensed form in the amount necessary to re-establish the specified water solids ratio. Therefore, according to the increasement of consumption of processed milk, the necessity for study about the quality of processed milk mixed with reconstituted milk arose.

• Journal of the Korean Society of Food Culture
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• v.28 no.4
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• pp.392-400
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• 2013

The purpose of this study was to determine the optimal amounts and mixing condition of skim milk powder (A), and roselle (B) for the production of yogurt prepared with roselle. The experiment was designed according to the central composite design for estimating the response surface method, which yielded ten experimental points, including two replicates for the skim milk powder and roselle. The physicochemical and mechanical analysis of each sample, including pH (P<0.001), titratable acidity (P<0.001), color (P<0.05), viscosity (P<0.001), showed significant differences. Antioxidant properties (total phenolic content, DPPH free radical scavenging activity) and viable cell counts of lactic acid were significantly different (P<0.05). The sensory measurements were significantly different in color, flavor, sourness, texture, and overall quality (P<0.05). The optimal formulation, calculated by numerical and graphical methods, was 7.82 g of skim milk powder and 2.09 g of roselle. From findings of this study, the roselle may be used in yogurt and can be applied for other food industries.

• Food Science and Preservation
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• v.10 no.2
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• pp.175-181
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• 2003

Yogurt base was prepared from skim milk supplemented with sweet persimmon powder at the levels of 4% and 7％ and was fermented with Lactobacillus acidophillus. Sweet persimmon powder contained protein 2.2%, fat 30.5%, carbohydrate 56.6% and ash 2.5%, Quality characteristics of prepared yogurt were evaluated for acid production(pH), visible cell numbers, sensory property and oganic acid compositions during fermentation. Lactic acid content in yogurt supplemented with sweet persimmon powder was higher (1.12%∼l.21%) than that (1.05%) in yogurt made with only skim milk after 24 hours fermentation. The sensory score was higher yogurt made with skim milk than yogurt supplemented with sweet persimmon powder in taste, texture and overall acceptability. However, the acid production in yogurt supplemented with sweet persimmon powder were not significantly difference compared to yogurt made with skim milk The antioxidative activity by DPPH(a-a'-diphenyl-${\beta}$-picrylhydratyl) method in yogurt supplemented with sweet persimmon powder and yogurt made with skim milk were higher than BHT 0.005 ％ used as control.

• Journal of Dairy Science and Biotechnology
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• v.37 no.3
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• pp.177-186
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• 2019

Raphanus raphanistrum subsp. sativus (radish) powder contains several bioactive com- pounds and is widely used in the food industry. In this study, we examined the sensory attributes (taste, color, flavor, texture, and overall acceptability) of commercially available milk, yoghurt, and kefir containing different concentrations of R. raphanistrum subsp. sativus powder. The organoleptic characteristics of commercially available milk, yoghurt, and kefir was significantly different with respect to taste, flavor, color, texture, and overall acceptability in the treated group (1%, 2%. 3%. and 4%) compared to the control (0%; p<0.05). In addition, the scores of taste, flavor, color, texture, and overall acceptability decreased in proportion to the increase in amount of radish-powder in commercially available milk, yoghurt, and kefir. When 1% R. raphanistrum subsp. sativus powder was added to commercially available milk, yoghurt, and kefir, they showed good results in organoleptic characteristics compared to the control group. Therefore, our results could be used as the basis for estimating changes in organoleptic characteristics on supplementation of various dairy products with R. raphanistrum subsp. sativus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.254-260
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• 1995

Yogurt base were prepared from milk added with skim milk powder or Aloe vera powder and femented with lactic acid bacteria(the single or mixed strain of Lactobacillus bulgaricus and Streptococcus thermophilus). The yogurt product were evaluated for acid production(pH, titratable acidity), number of viable cell, viscosity, sensory property and quality-keeping property. The composition of organic acid were also analyzed by HPLC. Addition of Aloe vera remarkably accelerated acid production, and titratable acidity of Aloe vera yogurts(1.293∼1.407%) after 24 hours incubation was higher than that of yogurts added with only skim milk powder(9.98∼1.110%). Yogurt fermented with the mixed strain of L. bulgaricus and Sc. thermophilus was more acidic than that of single strains. The propagation of lactic acid bacteria was stimulated by Aloe vera and the number of viable cell after 24 hours incubation were above 9.87log CFU/ml. Viscosity of Aloe vera yogurt(3,860∼4,300CPS) was higher than that of yogurt with only skim milk powder(2,402∼2,604CPS). The overall sensory score of Aloe vera yogurt femented by mixed strain was the best of tested yogurt. When yogurt with Aloe vera was kept at 5℃ for 15 day, it's quality-keeping property was relatively good. The major organic acid of Aloe vera yogurt was lactic acid and lactic acid content of yogurt increased by addition of Aloe vera powder. The citric acid content decreased wtih fermentation and malonic acid, pyroglutaric acid and α-ketoglutaric acid were analyzed out a little.

• Journal of Dairy Science and Biotechnology
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• v.15 no.1
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• pp.53-57
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• 1997

Hokkaido, as center of Japanese dairying, 3.48 million tons of raw milk which was about 40% of total production in Japan were produced from 11,400 farms in 1996. The average herd size and the annual volume of milking per head in Hokkaido were 78 head, 7,200kg, and the quality of raw milk also is much better than that of other area in Japan. Raw milk having less than 100,000/ml in viable count and less than 300,000/ml of somatic cell count were 99.6%, 93% respectively. In spite of producing large amount of high quality milk, only 26% of total amount was processed as market milk and 76% was used for making dairy products like butter, cheese and milk powder. Therefore, because of big difference in price between the raw milk for market milk and for dairy products. the income of dairy farms are much less comparing to other parts of Japan, where most of the raw milk are consumed as market milk.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.546-554
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• 1997

Gel-type yogurt was prepared from egg white powder (3%, w/v), glucose (2%, w/v) and four kinds of milk products (4%, w/v). The effects of milk product on acid production and growth of Lactobacillus were studied. The effects of milk product on sensory property and volatile aroma compounds were also studied. Acid production by L. acidophilus at 24 hr in samples containing milk product was significantly lower than that by L. acidophilus in milk (p<0.05). The sample containing casein produced less acid than the other samples. Number of viable cells of L. acidophilus at 24 hr in milk and samples containing milk product was $2.0{\times}10^{9}/mL$ and $5.0{\times}10^{8}{\sim}8.0{\times}10^{8}/mL$, respectively. Sensory property of the samples containing milk product was lower than that of milk yogurt (reference). However, sensory property of the sample containing casein was not significantly different from that of milk yogurt (p<0.05). The sample containing whey powder showed lower sensory score than other samples. Though the composition of volatile aroma compounds was slightly different from sample to sample, gas chromatographic analysis detected acetone, ethanol, diacetyl and acetoin in samples fermented by L. acidophilus.

• Food Science and Preservation
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• v.10 no.2
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• pp.236-240
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• 2003

This study was carried out to obtain fundamental data when developing new colostrum component fortified milk products. Residual immunoglobulin G (IgG) activities of both IgG fortified milk products under different pasteurization conditions and colostrum fortified milk powder products under different dissolving temperatures were measured. In the study, residual IgG activities of raw milk and IgG (50 mg and 250 mg) fortified milk products were sharply reduced upon increasing the temperature of heat treatment. After the low temperature long time (LTLT) treatment residual IgG activities of raw milk, IgG 50 mg and 250 mg fortified milk products decreased to 79%, 30％ and 21.6%, as compared to those before heat treatment respectively. However, almost no residual IgG activities were detected when IgG fortified milk was heated at 95$^{\circ}C$ for 15 sec. There was no significant change in the residual IgG activities of IgG fortified milk powder products upon different dissolving temperatures (30$^{\circ}C$, 40$^{\circ}C$, 50$^{\circ}C$ and 60$^{\circ}C$).

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.436-445
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• 2015

The effects of substituting whey protein concentrate (WPC) powder for rice flour in the preparation of seolgiddeok were determined by objective and subjective tests. Milk whey is drained from milk curd as a by-product of the cheese manufactureing process. Whey protein is known as a good nutritional source and is a functional material for many processed foods. WPC contains more than 80% whey protein. The moisture content decreased gradually during storage and the decrease in moisture was less in the control than in the WPC powder substituted groups. The color lightness (L) decreased significantly as the amount of WPC powder increased, wherease redness (a) and yellowness (b) both increased. Texture analyses revealed that the hardness, chewiness, gumminess and adhesiveness of seolgiddeok tended to increase in proportion to the amount of WPC powder in the formula. Seolgiddeok gelatinization was investigated by amylographing. Initial pasting temperature, peak viscosity, hot pasting viscosity and breakdown were low in seolgiddeok prepared with WPC powder substituted for rice flour. Setback had the lowest value in the control. Sensory evaluations revealed that, seolgiddeok prepared with 3% WPC powder had the highest overall acceptability score. These results indicated that WPC seolgiddeok with 3% WPC powder has the best quality.

• Journal of the Korean Society of Food Culture
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• v.24 no.5
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• pp.561-569
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• 2009

The effects of substituting whey protein isolate (WPI) powder for rice flour during the preparation of paeksulgi (Korean rice cake) were evaluated by objective and subjective tests. Milk whey is drained from milk curd as a by-product of the cheese manufacturing process. Whey protein is known as a good nutritional source and a functional material for many processed foods. WPI contains more than 90% whey protein. The moisture content decreased gradually during storage and the decrease was less in control than WPI powder-substituted groups. The color lightness (L) decreased significantly with increasing WPI powder, wherease the redness (a) and yellowness (b) both increased. Texture analyses revealed that the hardness, chewiness, gumminess, adhesiveness and fracturability of paeksulgitended to increase in proportion to the amount of WPI powder added. Evaluation of the gelatinization of paeksulgi by amylographing revealed that the initial pasting temperature, peak viscosity, hot pasting viscosity and breakdown was lower in samples that contained WPI powder. However, the lowest setback value was observed in the control. The results of the sensory evaluation indicated that paeksulgi prepared with 2% WPI powder had the highest overall acceptability. Taken together, these results suggest that WPI paeksulgi containing 2% WPI powder has the best quality.