• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.441-450
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• 2013

The purpose of this study was optimization of the conditions for mixing different amounts of red radish (Raphanus sativus L.) sprout powder, butter, and sugar when baking domestic wheat cookies prepared using red radish sprout powder. Response surface methodology, with a central composite design comprising 5 levels and 3 variables, was used to identify the best possible combination of amounts of red radish sprout powder ($X_1$), butter ($X_2$), and sugar ($X_3$). The physical and mechanical properties of each of the 20 samples analyzed, including color L (p<0.001), color a (p<0.01), color b (p<0.001), spread ratio (p<0.001), and hardness (p<0.01), differed significantly. The results of sensory evaluations, including color (p<0.001), appearance (p<0.001), texture (p<0.001), flavor (p<0.01), taste (p<0.001), and overall quality (p<0.001) also differed significantly among the samples. The optimal compositional ratios were 5.15 g for the red radish sprout powder, 64.84 g for the butter, and 47.18 g for the sugar.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.730-735
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• 1996

Antibacterial action of garlic extract against Escherichia coli was investigated. When the survival of E. cloi in tryptic soy broth (TSB) containing 50% garlic extract was compared with those of Lactobacillus plantarum, Leuconostoc mesenteroides and Staphylococcus aureus, E. coli was the most sensitive to garlic antibacterial action. When E. coli was inoculated into TSB with different concentrations of garlic extract, viable cell number decreased continuously during the test period even at 1% garlic extract. When E. coli was inoculated into pH-adjusted TSB containing 0.5% garlic extract, viable cell number of E. coli decreased continuously at initial pH of 5.2 and 6.2, while it decreased initially but increased to $8.0{\times}10^{7}\;CFU/ml at 48 hr at pH 7.2. With larger initial populations $(10^{6}\;CFU/ml), E. coli grew without apparent inhibition, while with smaller initial populations $(<10^{5}\;CFU/ml), viable cell number decreased initially but later increased. Thiol compounds like cysteine and glutathione, with free SH group (s), helped E. coli to grow or survive better in TSB with inhibitory level (5%) of garlic extract. The possibility of eliminating E. coli by using garlic extract from foods like kimchi of which garlic is one of regular ingredients is suggested.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.238-244
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• 1983

The cooking quality of irradiated chestnut after longterm storage were evaluated. 1. Color degree and tannin content of irradiated chestnut were slightly increased with the storage, but there was a little difference according to the radiation dose after nine months storage. 2. The main component of free sugars in the irradiated chestnut were identified as sucrose, glucose, fructose and the amino acids of chestnut were identified in the decreasing order of glutamic acid, aspartic acid, leucine, arginine, glycine, alanine, serine, pheylalanine, threonine, valine, isoleucine, tyrosine, methionine and cystein. Free sugars and amino acids of 25 Krad irradiated group showed a little difference compared with those of control group after nine months storage. 3. The calorie of candied chestnut prepared from nine months stored was marked 199 Kcal/100g of edible parts compared with 159 Kcal of raw chestnut. 4. Texture and sensory evaluation of candied chestnut prepared from nine months stored were better in 20-25 Krad irradiated group than in control group.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.55-60
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• 1986

The effects of temperature (70-$100^{\circ}C$), pH (3-8) and various sugars were investigated on the reaction rate, activation energy and z-value of Maillard reaction of 0.8m sugar and 0.8m glycine mixture. The sugars compared were glucose, fructose, lactose and sucrose, and the reaction was evaluated by absorbances at 278nm for pyrazine compounds and at 400nm for brown pigments. Fructose-glycine mixture showed a faster initial reaction rate than that of glucose-glycine, which was reversed by the order of glucose > fructose > lactose > sucrose after 10 hrs of reaction at pH 5.8 and $100^{\circ}C$. Generally, higher activation energy was required for forming pyrazines than that of brown pigment development. The highest z-value was obtained for lactose-glycine mixture, followed by glucose or fructose-glycine which had almost same z-value. The reaction rate was little affected by the pH change in the range of 4-6, while pH < 3 and pH 6-8 caused a significant increase in the rates.

• Journal of Practical Engineering Education
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• v.14 no.3
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• pp.505-512
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• 2022

The purpose of this study is to synthesize effects of the living lab-based education through meta-analysis. Seven primary studies reporting the effect of living lab-based education were carefully selected for data analysis. Research questions are as follows. First, what is the overall effect size of the living lab-based education? The overall effect size refers to the effect on the cognitive and affective domains. Second, what is the effect size of the living lab-based education according to categorical variables? Categorical variables are outcome characteristics, study characteristics, and design characteristics. Results are summarized as follows. First, the overall effect size of living lab-based education was 0.347. Second, the effect size according to the cognitive domain was 1.244 for information process, 0.593 for communication, 0.261 for problem solving, and 0.26 for creativity. Third, the effect size according to subject area was shown in the order of electrical and electronic engineering 1.146, technology and home economics 0.489, artificial intelligence 0.379, and practical arts 0.168. Fourth, the effect size according to school level was 1.058 for high school, 0.312 for middle school, and 0.217 for elementary school. Fifth, the effect size by grade level was 0.295 when two or more grades were integrated and 0.294 for a single grade.

• 대한공업교육학회지
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• v.37 no.1
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• pp.65-85
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• 2012

This study focuses on the 'invention technique and practical experience' unit to observe how the colleague mentoring class has its effect on self-efficacy. For this, we have selected experimental group and comparative group and proceeded the experiment. For five classroom hours of the 'technique of invention and practical experience' unit, each group was assigned different method to do the experiment. The experimental group was applied with the colleague mentoring method and the comparative group was applied with the self study method. To observe the differences of how it effects on one's self-efficacy, the questionnaire was distributed before and after class. Then, it was verified for the meaningful differences between the two groups. To summarize, the results are as follows. First, for self-efficacy experiment, the questionnaire before the experiment showed that there were no differences found between two groups. However, the questionnaire collected after the experiment showed great differences. The group with the colleague mentoring showed more meaningful differences at p<.05 significance level than comparative group. Furthermore, by observing the before and after questionnaire, it was found that both groups showed statistically meaningful differences at p<.05 significance level, but the experimental group showed greater self-efficacy improvements than comparative group. Second, when further examining the self-efficacy, the activity start expectation, activity continuation expectation, activity performance expectation, and experience recovery expectation showed the statistically meaningful differences at p<.05 significance level. According to the above results, it can be stated that the colleague mentoring class has more positive effects on the self-efficacy than self-study class. Summing up, the colleague mentoring class is more effective than self-study for fostering student's self-efficacy.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.838-844
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• 1989

The physicochemical and organoleptic properties of Korean pickled cucumbers were studies for their changes during fermentation. The Korean pickled cucumbers were prepared by salting in 5-15% NaCl solution and fermented for 7-10 days. The results showed that the increase of salt concentration in cucumber had a linear relationship with logarithmic value of brining time. The higher NaCl concentration in salt solution resulted a rapid salt penetration into cucumber while the rate of changes in pH, the total acidity and turbidity were reduced. The color of cucumber surface were changed from green to yellow-green color as the fermentation progressed. The hardness of cucumber decreased repidly after one day of fermentation, followed by a little decreased until it reached to pH 3.2. A little increase in pH and decrease in total acidity were measured thereafter. The evaluation of sensory quality showed that the acidic and fresh cucumber-like-flayer decreased and yeast-moldy increased as the fermentation progressed. The sensory changes were more evident for lower salt concentration of NaCl solution. The softness of cucumber became to be significant from 4th day of fermentation in 5% salt solution.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.231-237
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• 1983

In order to develop the commercial storage method of chestnut by irradiation combined with natural low temperature, a chestnut variety Ok-gwang was stored in a natural low temperature storage room ($450{\times}650{\times}250$ cmH; year-round temperature change, $2-17^{\circ}C$; R.H., 80-85%) on batch scale followed by irradiation with optimum dose level. Sprouting rate of chestnut was 100% after seven month storage in control whereas that of 20-25 Krad irradiated group was only 5-15%. In comparison of rotting rate, weight loss and texture, 25 Krad irradiated group was better than that of control. Moisture and reducing sugar were increased in contrast with the decrease of total sugar during nine month storage and these changes were more remarkable in control. Ascorbic acid content was slightly decreased both in control and irradiated group; more decrement was noticed in control.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.802-807
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• 2001

Effects of ${\beta}-glucan$ from Lentinus edodes and hordeum vulgare on blood glucose and lipid composition were investigated. Diabetes mellitus was induced in male ICR mice by the injection of alloxan into the tail vein at a dose of 75 mg/kg. The ${\beta}-glucan$ were administered orally for 10 days and the normal and alloxan-control group were orally administered with saline. The body weight gain and food intake were monitored every day and plasma levels of glucose, triglyceride, total cholesterol, LDL-cholesterol were determined at last day. Also the weight of liver, heart, spleen and kidney were determined. The ${\beta}-glucan$ from Lentinus edodes and hordeum vulgure lowered significantly body weight gain in alloxan-induced diatetic mice (p<0.05) and plasma glucose levels compared to that of alloxan-control group. Plasma triglyceride level in B500 was lowered in alloxan-induced diabetic mice. The ${\beta}-glucan$ of hordeum vulgare lowered weight of liver significantly (p<0.05). In conclusion, it was assumed that ${\beta}-glucan$ from hordeum vulgare have anti-hyperglycemic and anti-obese effects by reducing body weight gain and decreasing serum glucose and triglyceride level.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1619-1627
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• 1999

Microbiological characteristics of gamma irradiated low salt squid Jeot-gal were examined. Following the fermentation periods, total bacterial cell, Lactobacillus spp., Staphylococcus spp., Streptococcus spp., Pseudomonas spp. and yeast cell number were counted on their selective media and some acid forming bacteria and Pseudomonas spp. were identified. As the gamma irradiation dose increased, the microbial density of early fermentation phase was reduced and the growth rate was delayed. The repression effects on microbiological growth by gamma irradiation were to be higher as salt concentration increased. Adequate conditions of salt concentration and gamma irradiation for low-salt squid Jeot-gal preparation were 10% and 10 kGy, respectively. Lactobacillus sp. 2, Micrococcus varians and Streptococcus sp. I were isolated from 5% salt containing squid Jeot-gal, and Micrococcus morrhuae was from 20% only while Lactobacillus plantarum and Lactobacillus brevis were widespread. Lactobacillus brevis, Pediococcus halophilus and Pseudomonas diminuta were sensitive and Lactobacillus plantarum, Micrococcus morrhuae and Pseudomonas sp. 3 were resistant to gamma irradiation. The diversity of microflora decreased as salt concentration decreased and gamma irradiation dose increased.