• Korean Journal of Food Science and Technology
• /
• v.35 no.6
• /
• pp.1007-1016
• /
• 2003

Garlic was stored at 4, 8, and $12^{\circ}C$ to investigate the development of green discoloration. Green discoloration developed after 7 day of storage ar $4^{\circ}C$, while it developed after 15 day of storage at 8 and $12^{\circ}C$. The effect of maleic hydrazide fertilization on green discoloration of garlic was not observed. Green discoloration of garlic was accelerated by gamma-radiation treatment. The addition of cysteine did not prevent green discoloration, which decreased the commercial value of the garlic due to the presence of white specks on the surface. When 3% ascorbic acid was added to the garlic, green discoloration developed in 6 and 24 hr at room temperature and $4^{\circ}C$, respectively. The tendency of garlic to discolor was also investigated at various storage temperatures. Discolored garlic stored for 30 day at low temperatures was conditioned at $20{\sim}45^{\circ}C$ for 20 day. The green discoloration of garlic conditioned at 20 and $25^{\circ}C$ did not disappear in 20 day, but disappeared in 20 day when conditioned at $30^{\circ}C$. The L, a, and b values of garlic conditioned at 35, 40, and $45^{\circ}C$ for 4 day were similar to those of normal garlic. Conclusively, our results indicated that the best method for suppressing green discoloration was conditioning discolored garlic at $35^{\circ}C$ for 4 day.

• Korean Journal of Food Science and Technology
• /
• v.35 no.6
• /
• pp.1193-1198
• /
• 2003

The effects of preferment levels prepared with lactic acid bacteria isolated from kimchi on the quality of white pan bread were studied. The aim was to investigate how preferment influenced the baking-technological, textural, and sensory properties of white pan bread. During the process of making white pan bread, the pH decreased as the preferment levels increased, whereas the titratable acidity increased. The loaf specific volume increased from 4.66 to $5.59\;cm^3/g$ as preferment content increased from $10%{\sim}25%$. The moisture content and water activity of the bread ranged from 40.77 to 41.49%, and 0.961 to 0.966, respectively, indicating that no appreciable differences were related with the preferment levels (p<0.05). The textural characteristics of white pan bread were highly correlated with the amount of preferment added. White pan bread containing preferment showed a decrease in hardness and gumminess, and an increase in springiness. The color of white pan bread was not significantly different from that of the control. In sensory evaluation, the values for volume, springiness, and umami were highest in the white pan bread with 20% preferment, and the sour and umami tastes increased with the amount of preferment.

• Korean journal of food and cookery science
• /
• v.7 no.4
• /
• pp.63-69
• /
• 1991

This study was undertaken for the purpose of studying the physicochemical propery of mungbean and texture of mungbean starch gels. Mungbean starch gel made with different levels of oil were tested to investigate the textural characteristics by mechanical test. The results are summerized as fallows: The content of moisture fat, protein, and ash in Seonwha mungbean were shown to be about 13.19%, 1.02%, 23.57% 3.13% respectively. Those of Seonwha mungbean crude starch were 12.48%, 0.63%, 0.94%, 0.13% respectively. The gain of dry crude starch from peeled mungbean was 22.48%. Water binding capacity of Seonwha mungbean crude starch was 183.1%. The pattern of change in swelling power of Seonwha mungbean crude starch for increasing temperature increased slowly to $70^{\circ}C$, and then increased rapidly. The pattern of change in solubility was similar to that of swelling power. The amylose and amylopectin content were 22.5%, 77.5%. Brabender hot-paste viscosities of mungbean crude starch at 8% and 10% showed the similar amylogram patterns with peak vicosity. By the Rheometer measurement result of 8% 10% mungbean starch gel, Hardness and Fractuability tended to be decreased as the addition level of oil increased. Elasticity, Adhesiveness, Chewiness, L, a, and b value tended to be increased as the addition level of oil increased.

• Korean journal of food and cookery science
• /
• v.20 no.2
• /
• pp.126-132
• /
• 2004

To develop health food using old pumpkin, freeze-dried old pumpkin powders were added into wheat flour in the ratio of 0, 1, 2, 4, and 8% and the quality characteristics of the baked products were investigated. Moisture content and water activity of breads with added pumpkin powders were raised from 42.22 and 0.528 in 1% addition ratio to 0.576 and 44.39% in 9% addition ratio compared to 40.69% and 0.521 in the bread of non-added, respectively and these increases were due to the effect of the added pumpkin powders. Water holding capacity of the added pumpkin powders raised the weight of the breads while the specific volume was decreased at that time. In the Hunter's color values, as the pumpkin powders content increased, 'L' and 'a' values were decreased while 'b' value was increased from ＋29.44 in 1% addition ratio to ＋45.58 in 8% addition ratio of freeze-dried old pumpkin powders compared to ＋12.65 in the bread of non-added. In the texture properties, hardness, fracturability, springiness, cohesiveness, gumminess and chewiness were increased by the added content of pumpkin powders hardness to 561 g in the bread withof 8% added pumpkin powders from 248 g in the bread of non-added. Judging from texture, taste and overall acceptability of the product, the recommended substitution level for freeze-dried old pumpkin powders in bread was 4% or less

• Korean journal of food and cookery science
• /
• v.15 no.6
• /
• pp.652-658
• /
• 1999

Arrowroot Mook was prepared as a trial to develop new food items from natural resources, and its rheological properties were measured. 1. The starting point of gelatinization of 7% arrowroot starch solution was $67.5^{\circ}C$ as measured by amylograph. The viscosity of arrowroot starch reached the maximum 375 B.U. at $95^{\circ}C$ and decreased to 315 B.U. while holding at $95^{\circ}C$ for 15 min. When the temperature dropped to $50^{\circ}C$, the viscosity increased again to 530 B.U. 2. The gelatinization enthalpy of arrowroot starch was 15.603 J/g. 3. For the color, there were significant differences in b value for the arrowroot Mook made of arrowroot starch and in L value for the Mook made by the addition of arrowroot juice. 4. In descriptive analysis, $S_3$(14% arrowstarch) was most favored in color, and $S_1$(10% arrowstarch)was most favored in transparency, brittleness, fineness, and shininess. There were no significant differences in hardness, adhesiveness, and astringency. 5. On the contrary to mechanical measurement, there were no significant differences in hardness of samples as the addition of arrowroot juice increased, although there appeared a tendency to be softer in descriptive analysis. 6. The Mook prepared with 12% arrowroot starch was most favored by sensory evaluation. In case of adding arrowroot juice, the Mook containing 3% of arrowroot juice was most favored. Overall, arrowroot Mook showed a potential as a new food item.

• Korean journal of food and cookery science
• /
• v.15 no.6
• /
• pp.633-638
• /
• 1999

This study was conducted to investigate the effect of quality preservatives on minimally processed white radish for Kkakttugi, hot radish Kimchi, preparation during storage at $4^{\circ}C$ and $20^{\circ}C$. The firmness of minimally processed white radish decreased during storage at $4^{\circ}C$ and $20^{\circ}C$. However 1% $CaCl_2$ and 2% NaCl+2% sucrose treatments were effective to maintain the firmness of cut radishs. For color, Hunter L values decreased more in the samples stored at $20^{\circ}C$ than at $4^{\circ}C$, while a values showed a slight increase at both storage temperatures. The b values (browning index) showed a notable increase during storage at $4^{\circ}C$ and $20^{\circ}C$. Vitamin C content decreased during storage at both temperatures by 10.4% ~ 95.9%. At both storage temperatures, vitamin C content was highest in the samples treated with 1% NaCl+1% sucrose. For organic acid, while the content of malic acid decreased those of lactic and acetic acid increased during storage.

• Korean journal of food and cookery science
• /
• v.31 no.4
• /
• pp.395-404
• /
• 2015

The aims of this study were to determine the optimal mixing condition for two different amounts of Gynura procumbens powder and olive oil for the preparation of beef sausage. The experiments were designed according to the central composite design of response surface methodology, which showed 10 experimental points including two replicates of Gynura procumbens powder and olive oil. The physicochemical and mechanical characteristics as well as the sensory properties were measured, and these values were applied to the mathematical optimization models. The results of the physiochemical and mechanical analysis of each sample, including chewiness, cohesiveness, color a, color b, moisture content, salinity and heating loss showed significant differences. The sensory measurements were significantly different in color, flavor, tenderness, texture and overall quality. The optimum formulation, which was calculated using the numerical and graphical method, was determined to be 2.1 g Gynura procumbens powder and 7.06 g of olive oil.

• Korean journal of food and cookery science
• /
• v.28 no.2
• /
• pp.111-121
• /
• 2012

The purpose of this study was to investigate the quality characteristics of Garaedduk with regard to the amount of added whole soybean curd (Chun-Tofu). Whole soybean curd was added in amounts of 0, 3, 6 and 9%. Whole soybean curd Topokki dduk was stored at room temperature for 48 hours. The moisture contents had no significant difference for increases in the amount of whole soybean curd. The L value and b values of Garaedduk increased significantly with increases in the amount of whole soybean curd. Texture characteristics of Garaedduk measured with a texture analyzer revealed that hardness and cohesiveness decreased significantly for different amounts of whole soybean curd, and hardness increased significantly and cohesiveness and chewiness decreased with increase of storage time. As for sensory characteristics, samples with 9% added whole soybean curd rated higher in overall acceptability compared with other samples. In regard to cooking properties, water absorption increased and solid contents decreased with increases in the amount of whole soybean curd. Therefore, Garaedduk containing 9% whole soybean curd was most preferable.

• Korean journal of food and cookery science
• /
• v.26 no.6
• /
• pp.677-684
• /
• 2010

The purpose of this study was to investigate the effects of black foods (black rice and black garlic) and the ratio of black garlic on the quality of Sulgiddeok. Pasting properties as measured by a rapid visco analyzer (RVA) were lower for black rice flour than white rice flour. Colorimetric analysis revealed that L, a, b values were dependent on the type of rice. For texture profiles, texture was associated with RVA profiles. During storage, hardness of black rice Sulgiddeok increased to a lesser degree than that of control. After observation via scanning electron microscopy (SEM), black rice Sulgiddeok showed a honeycomb-like network structure. In sensory analysis, black rice Sulgiddeok showed a tendency to prefer the control. The addition of appropriate black garlic (BG1) helped to improve the quality. In accordance with the aforementioned results, decreased retrogradation related to black rice Sulgiddeok and black foods (black rice and black garlic) could result in quality products with high nutritional value.

• Korean journal of food and cookery science
• /
• v.26 no.3
• /
• pp.307-313
• /
• 2010

Yogurt base was prepared from skim milk added with 0.5, 1.0 and 1.5% (w/v) black garlic extracts(BGE, 60 brix), fellowed by fermentation with Lactic acid bacteria (the mixed strain of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus) at $42^{\circ}C$ for 24 hr. The yogurt products were evaluated for acid production (pH, titrable acidity), number of viable cells, viscosity, color value, and sensory properties. The pH of yogurt with BGE was below 6.0 at 6 hr fermentation, after which it was rapidly acidifies. Aftert 24 hr, the titratable acidity of yogurt with 1.5% BGE was 0.74%, which was 5.7 times higher than that before fermentation. There was no significant difference in viable cell count between the samples after 3 hr fermentation. The viscosity of yogurt was decreased by the addition of BGE. As the percentage of BGE increased, the L value (lightness) decreased while the a value (redness) and b value (yellowness) increased. The overall sensory score of yogurt with BGE was lower than that of yogurt with only skim milk. Therefore, moderate addition of BGE was below 1% for the preparation of yogurt.