• Culinary science and hospitality research
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• v.12 no.2 s.29
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• pp.195-205
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• 2006

In this study, we investigated the quality characteristics of curd yogurt with different content of Rubus coreanus Miquel juice. Yogurt was fermented with three kinds of lactic acid bacteria(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei). The changes of quality characteristics were investigated during fermentation and an acceptance test was performed after fermentation. The pH was decreased on the whole, and titratable acidity was gradually increased during fermentation. The number of viable cells was increased in case of yogurt with 1% to 4% Rubus coreanus Miquel juice, while it was inhibited in the sample with 6% and 7%. There was similar content in composition of protein, lactose, FFA, TS and NFS of curd yogurt after fermentation. Color value of curd yogurt with Rubus coreanus Miquel juice was higher in L(brightness), a(redness) and b(yellowness), compared with the control. Sensory attributes of color, odor, taste, after taste and overall acceptability of the curd yogurt with 3% Rubus coreanus Miquel juice showed highest preference among samples.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.160-166
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• 2007

Response surface methodology (RSM) was used for the optimization of the baking process of cookies made with onion powders (onion cookie). Experiments were carried out according to a central composite design, selecting onion powder content $(1.15{\sim}8.86%)$ and baking temperature $(155.9{\sim}184.1^{\circ}C)$ as independent variables and pH, titratable acidity, moisture content, density, spread factor, CIE color parameters $(L^{\ast}-$, $a^{\ast}-$, and $b^{\ast}-values)$, and hardness as response variables. pH decreased with increasing amount of onion powder and baking temperature. Moisture content also decreased as the baking temperature increased. $L^{\ast}-$ and $b^{\ast}-values$ decreased but $a^{\ast}-values$ increased with increasing onion content and baking temperature. Most polynomial models developed by RSM were highly effective to describe the relationships between the studied factors and the responses. Overall optimization, conducted by overlaying the contour plots under investigation, was able to point out the optimal range of the independent variables within which the six responses were simultaneously optimized. The point chosen as representative of this optimal region corresponded to 4.01% onion powder content and $161.84^{\circ}C$ baking temperature. The predicted dependent or response values in the optimal region were: pH＝6.87, moisture content＝2.77%, $L^{\ast}-value＝68.45$, $a^{\ast}-value＝1.98$, $b^{\ast}-value＝34.64$, and spread factor＝9.41.

• Horticultural Science & Technology
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• v.34 no.5
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• pp.761-770
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• 2016

This study investigated the variation in fruit characteristics between different triploid progenies derived from a cross between tetraploid and diploid grape cultivars, with the aim of developing high quality, labor-saving triploid grapes. No differences were found in fruit quality traits such as soluble solids content and titratable acidity, whereas significant variation was noted in cluster weight induced by a one-time application of GA3 (100 ppm) on the triploid progeny of different cross combinations. The cluster weight was higher in progeny obtained from 'Kyoho' ${\times}$ 'Sekirei' than for offspring derived from other cross combinations; deviation in the mean cluster weight was also small for 'Kyoho' ${\times}$ 'Sekirei' progeny. These results suggest that specific cross combinations, such as 'Kyoho' ${\times}$ 'Sekirei', can be used to efficiently breed new, labor-saving seedless grape cultivars.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.410-417
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• 2017

We compared the quality of 'Fuji' apples (Malus ${\times}$ domestica) from trees whose leaves were not removed (no artificial defoliation; NAD) with apples from trees that underwent early defoliation (ED, treated in mid September and early October) and conventional defoliation (CD, treated in early and mid October). The experiment was conducted in three consecutive years using 15-year-old 'Fuji' apple grafted on Malus prunifolia. Fruits were harvested on November 7, 16 or 12 in 2011, 2012 and 2013, respectively. Compared to NAD treatment, ED and CD treatment reduced the fresh weight by 4.7% and 0.6%, respectively. The soluble solids content of NAD apples ($14.4^{\circ}Brix$) was slightly higher than that of CD ($14.1^{\circ}Brix$) and ED ($14.0^{\circ}Brix$) apples. Soluble sugar content, flesh firmness, water-core index, and titratable acidity were not affected by defoliation treatment regardless of treatment timing. The skin blush index of NAD apples (2.3) was inferior to that of CD (3.3) and ED (3.4)- treated apples. Furthermore, artificial defoliation treatments increased skin redness ($a^*$) and yellowness ($b^*$) and significantly improved the degree of skin blush compared to NAD fruits.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.189-196
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• 2015

The aim of this study was to manufacture functional high protein fermented beverage, using whey protein concentrate (WPC) and Lactobacillus plantarum DK211 isolated from kimchi, and to evaluate the physicochemical, functional, and sensory properties of the resulting product. The fermented whey beverage (FWB) was formulated with whey protein concentrate 80 (WPC 80), skim milk powder, and sucrose; and fermented with Lactobacillus plantarum DK211 as single, or mixed with Lactococcus lactis R704, a commercial starter culture. The pH, titratable acidity, and viable cell counts during fermentation and storage were evaluated. It was found that the mixed culture showed faster acid development than the single culture. The resulting FWB had high protein (9%) and low fat content (0.2%). Increased viscosity, and antioxidant and antimicrobial activity were observed after fermentation. A viable cell count of 10⁹ CFU/mL in FWB was achieved within 10 h fermentation, and it remained throughout storage at 15℃ for 28 d. Sensory analysis was also conducted, and compared to that of a commercial protein drink. The sensory scores of FWB were similar to those of the commercial protein drink in most attributes, except sourness. The sourness was highly related with the high lactic acid content produced during fermentation. The results showed that WPC and vegetable origin lactic acid bacteria isolated from kimchi might be used for the development of a high protein fermented beverage, with improved functionality and organoleptic properties.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.205-210
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• 2015

The objective of this study was to develop yogurt-cheese using cow’s milk, ultrafiltrated cow’s milk, and soy milk. The addition of soy milk and ultrafiltrated milk increased the amount of protein in the yogurt-cheese. Yogurt-cheeses were made using cheese base using 10% and 20% soy milk with raw and ultrafiltrated cow’s milk, and stored at 4°C during 2 wk. The yield of yogurt-cheeses made with added soy milk was decreased and the cutting point was delayed compared to yogurt-cheese made without soy milk. Yogurt-cheese made using ultrafiltrated cow’s milk showed the highest yield. However, yogurt-cheese made with added soy milk had higher protein content and titratable acidity than yogurt-cheese made using raw and ultrafiltrated cow’s milk. Fat and lactose contents in the yogurt-cheese made with added soy milk were lower. Yogurt-cheeses made with added soy milk contained several soy protein bands corresponding to the sizes of α₂-, β-, and κ-casein band. Yogurt-cheese made with added soy milk had similar elasticity to yogurt-cheese made without soy milk but had lower cohesiveness. There was no significant difference in the number of lactic acid bacteria in the different cheeses, as all had over 8.0 Log CFU/g. Considering these data and the fact that proteins and fats of vegetable origin with high biological value were observed as well as unsaturated fats, yogurt-cheese made with added soy milk can be considered to be a functional food.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.21-25
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• 1997

Application of the color indicators to kimchi packages was investigated in order to monitor the ripeness of commercial kimchi products during storage and distribution. Kimchi was packed in polypropylene (PP) tray and nylon/cast polypropylene (Ny/CPP) lid where the indicating sachet consisting of $CO_2$ absorbent and chemical dye (bromocresol purple and methyl red) was attached. The ripeness of kimchi during storage at $0{\sim}20^{\circ}C$ was measured in terms of pH and titratable acidity (TA), which were compared with Hunter color values of the indicators. The color of bromocresol purple dye turned from light blue to purple, while that of methyl red turned from light yellow to red. Regardless of the storage temperatures, Hunter b values of bromocresol purple type and Hunter a values of methyl red type appeared to be proportional to both the pH and TA values of kimchi. These results suggest that the color indicators be employed as one of the effective techniques for sensing the ripeness of packaged kimchi products without destructing the package.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.51-56
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• 1997

Effects of mustard seed (Brassica juncea) on the preservation of soup for Naengmyon were investigated, and morphological changes of E. coli treated with extract of mustard seed were examined. Titratable acidity of soup for Naengmyon treated with mustard seed was higher than that of control at initial stage, but became lower than control after 24 hours of preservation. The number of bacteria and E. coli in soup for Naengmyon added with mustard seed was lower than that of control, and the more mustard seed was added, the less bacteria and E. coli were observed. The content of volatile basic nitrogen (VBN) increased during preservation of soup for Naengmyon. The VBN content of soup for Naengmyon added with mustard seed was higher than that of control, and the more mustard seed was added, the lower VBN was detected. Scanning eletron microscopys of E. coli treated with extract of mustard seed showed that cell surface was distorted with shrinked cell mass.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.389-396
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• 2005

Physico-chemical properties of ssamjang prepared by industrial process were investigated. Overall experiments were planned by central composite design for five independent variables, kochujang mash aging period $(X_{1})$, doenjang aging period $(X_{2})$, doenjang content $(X_{3})$, sterilization temperature $(X_{4})$, and storage temperature $(X_{5})$. Storage period had no consistent effect on moisture content of ssamjang. Doenjang having longer aging period showed lower moisture content than that having shorter aging period. Titratable acidity and pH of ssamjang gradually increased and decreased with storage period, respectively, with pH of ssamjang significantly affected by aging period of doenjang and kochujang mashes, and sterilization and storage temperatures. Amino nitrogen contents of ssamjang increased during storage and were more affected by sterilization temperature than by aging period and content of doenjang, and storage temperature. Crude protein content of ssamjang irregularly changed during storage, and was slightly affected by content of doenjang.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.470-473
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• 2005

Effect of king oyster mushroom (Pleurotus eryngii) on kimchi quality was evaluated during fermentation at $5^{\circ}C$. Kimchi showed rapid decrease in pH up to 7 days, and thereafter slowly decreased. Titratable acidity of kimchi was inversely proportional to pH of kimchi. Treatment of king oyster mushroom did not significantly affect total microbial and lactic acid bacterial counts in kimchi. Antioxidant activity and overall-eating quality of blanched king oyster mushroom-added kimchi were highest among samples tested.