• Food Engineering Progress
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• v.15 no.4
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• pp.338-345
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• 2011

The pH, acidity, protein, color, reducing sugar, total sugar, alcohol and organoleptic characteristics of Takju containing 100% short grain rice (100 S), 100% long grain rice (100 L), 50 S+50% puffed rice powder (50 P) and 50 L+50 P were examined. After a drastic decrease during the initial stage of fermentation, the pH gradually increased except 100 L. Protein peaked at day 1 and decreased. A higher protein was noticed in puffed samples than in rice samples (p < 0.05). The Hunter "L" value decreased after a rise during the beginning of fermentation. Puffed samples showed higher reducing sugar than rice at day 0. Total sugar was similar to reducing sugar. A drastic increase in alcohol concentration was detected at day 2. Higher alcohol was observed in short grain than long grain and also in puffed samples than in rice (p < 0.05). A significant difference between 100 S and 100 L was observed in a sensory evaluation (p < 0.01); while no preference was detected.

• Food Engineering Progress
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• v.14 no.3
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• pp.235-242
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• 2010

This study was to investigate the combined effect of enzyme and trehalose addition on the retrogradation rate and quality changes in a Korean traditional rice cake, Backsulgi. As for the enzyme, a commercial maltogenic amylase, Novamyl, was used. From texture profile analysis and sensory tests, the optimum enzyme content for the preparation of Backsulgi was determined to be 0.1%. Backsulgi was prepared with the fixed content of Novamyl (0.1%) and different ratios (5, 10, 15%) of trehalose, and physicochemical and sensory properties were examined for 3 days of storage at ${25^{\circ}C}$. As trehalose content increased, the water activity of Backsulgi decreased. In Hunter's color value, L- and a-values of trehalose-added samples were significantly lower than those of control. In texture profile analysis, hardness of Backsulgi decreased with trehalose content. During storage, a increase in hardness and a decrease in cohesiveness were typically observed for all samples. However, those changes were significantly reduced with trehalose content. The retardation of retrogradation with the enzyme and trehalose addition was confirmed using calculated Avrami rate and time constants. These results revealed that combined treatments of 0.1% Novamyl and 10% trehalose could produce Backsulgi of better sensory quality with retarded retrogradation compared to separated treatment.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.221-226
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• 2019

This study investigated the optimal amount of shell powder (0.1, 0.2, 0.3, and 0.4%) to add to rice noodles containing 20% rice flour and compared their quality characteristics to those of wheat noodles containing a commercial alkaline reagent (added at 0.4%). As the amount of shell powder was increased, the L and b values (Hunter's color) increased. The pH, turbidity, and water absorption also increased as the amount of shell powder was increased. However, when the shell powder content exceeded 0.3%, the hardness, chewiness, springiness, and tension tended to decrease below acceptable levels. This might be because the shell powder inhibited network formation. The textural properties and pH value of rice noodles containing 0.2% shell powder were similar to those of the wheat noodles. This suggests that 0.2% shell powder may be the optimal amount to add to rice noodles when used as the alkaline reagent.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.632-640
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• 2020

In this study, we produced macarons by adding white bean powder at various proportions (0, 25, 50, 75, and 100%). The macarons in the 100% additive group had the highest moisture content, smallest volume, highest weight, and highest sugar and reducing sugar content. The macarons in the 50% additive group had the highest spread factor.Furthermore, their pH and acidity demonstrated the greatest air bubble stability. In the Hunter color system, by adding white bean powder, the L value gradually decreased, whereas the a and b values gradually increased. The hardness, gumminess, and chewiness decreased with the addition of white beans. Flavonoids and total phenolic compounds, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and superoxide dismutase (SOD)-like activity were the highest at 100%. Additionally, their overall acceptability was the highest at 50%. These results suggested that the use of white bean powder to produce macarons have numerous advantages.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.375-379
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• 2016

Atmospheric pressure plasma (APP) was applied to examine microbial safety and qualities of commercial Sunsik. APP was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air) and dielectric barrier discharge plasma treatment was applied for periods of 0, 5, 10, and 20 minutes. The total aerobic bacterial count in the control was 4.44 log CFU/g. Under plasma treatment for 20 minutes, Sunsik samples inoculated with Bacillus cereus, B. subtilis, and Escherichia coli O157:H7 resulted in a reduction of bacterial counts by approximately 2.20, 2.22, and 2.52 log CFU/g, respectively. The pH of the sample was found to decrease after APP treatment. Although hunter color $L^*$ of Sunsik increased, $a^*$ and $b^*$ value decreased as a result of APP. Increasing the APP time also enhanced the peroxide value. Further, sensory evaluation revealed that APP decreased color, flavor, taste and overall acceptability. The results of this study indicated that APP treatment improved the microbial quality of Sunsik, although further studies should be conducted to reduce the deterioration of sensory quality induced by APP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1030-1036
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• 2008

In Korea, many types of traditional grape wine have existed starting from seven hundred years ago and horse-blossom-like-grape (mayu-podo) was mainly cultivated. Korean traditional wine (KTW) was manufactured by a unique method in which grape juice-added porridge made from glutinous rice was fermented by nuruk as a starter for brewing. Unfortunately, KTW making was discontinued in 20th century; thus, restoration of Korean wine culture is needed. KTWs were prepared by four traditional methods, and their qualities were compared to commercial wine made by sugaring grape juice. Ethyl alcohol contents, total acidity, pH and amino acid of the four KTWs were $9.2{\sim}11.2%$, $0.93{\sim}1.20\;mg$/100 mL, $3.02{\sim}3.48$ and $0.80{\sim}0.88\;mg$/100 mL respectively. The KTWs showed higher values in total acidity and amino acid than those of commercial grape wine. KTWs were rich in maltose, acetic acid and lactic acid. L, a and b value in Hunter's color value ranged $3.59{\sim}3.69$, $20.63{\sim}38.06$, and $1.20{\sim}1.56$, respectively. Sensory quality properties in color, flavor, taste and overall of KTWs were not different from commercial dry wine. Contents of total phenolic compounds and free radical scavenging activity using DPPH of KTWs were $599.6{\sim}652.2\;mg$/100 mL and $50.59{\sim}56.75%$, respectively.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.1022-1031
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• 2008

Pound cakes were prepared with Citrus mandarin powder(CMP) cultivated in JeJu Island, Korea. The impact of CMP amount level, which was incorporated into wheat flour by the ration of 0, 5, 10, 15, and 20% based on a flour weight, on the rheology and sensory profile of the pound cakes was measured. Moisture content of 13.70%, crude protein 5.12%, crude lipid 1.30%, crud ash 1.92%, respectively. Also evaluation was performed on the changes in physicochemical properties of the pound cakes during storage at 4 and $30^{\circ}C$. According to the amylogram, gelatinization temperature of the control dough was $63.35^{\circ}C$ and those of the dough with CMP were $63.85{\sim}66.55^{\circ}C$. Maximum viscosity of the dough was 686 B.U in the control, those were 575 B.U, 553 B.U, 504 B.U and 401 B.U in the dough with 5, 10, 15, and 20% CMP, respectively. The retrogradation degree(setback value) of CMP dough was $31{\sim}57%$ lower than that of the control dough under the same conditions. Water holding capacity of pound cake was increased gradually in proportion to the amount of CMP. The CMP addition decreased the brightuess(L) of pound cakes but increased redness(a) and yellowness(b). Hardness of pound cakes was significantly increased by CMP addition, while springiness, adhesiveness and cohesiveness were decreased. Based on sensory evaluation, pound cakes added with CMP were not significantly different in color and texture, while that of 10% CMP was significantly high in taste, flavor, and overall preferences, compared to the control. pH of pound cake with CMP was decreased during storage, showing that pH of CMP samples was lower than the control. Titrated acidity of pound cake with CMP was increased rapidly from storage for 10 days, which the changes in degree was fast in accordance with CMP amount. The Hunter's color value of pound cake with CMP was decreased, as the storage time proceeded. In the samples prepared with CMP, the firmness, adhesiveness, gumminess and chewiness was increased as the storage time proceeded, while springiness and cohesiveness was decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1082-1090
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• 2005

Jocheong was prepared by adding Lentinus edodes extract to improve its quality and to give some functional properties. Contents of crude protein, ash and crude lipid were similar to those of control, while carbohydrate content was decreased. Total mineral content were $1,916.03\~2,674.24mg/kg$ that was no difference between test samples. From HPLC determination of free sugars, Jocheong was found to contain maltose as the highest sugar, followed by glucose and fructose. In amino acid analysis, seventeen amino acid were identified and quantified. Glutamic acid in Jocheong was major amino acid. The major fatty acids in Jocheong $(0\%,\;control)$ were linoleic acid, palmitic acid, oleic acid, myristic acid and caproic acid. There was no significant differences in fatty acid composition, pH and reducing sugar content among the Jocheong samples. The viscosity and solid contents tended to decrease with the addition of Lentinus edodes extract. Increasing the ratio of mushroom extract in Jocheong tended to decrease the lightness, yellowness and redness in Hunter's color value. Although sensory value decreased with increasing Lentinus edodes extracts, use of mushroom extracts (7: 3; saccharification liquids: Lentinus edodes extracts) is recommended for making Jocheong.

• Food Science and Preservation
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• v.23 no.5
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• pp.711-717
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• 2016

Opuntia humifusa fruits were investigated. The length of minor and major axis, and weight of O. ficus-indica and O. humifusa fruits were compared as the morphological features. The characteristics of components such as color, moisture, crude protein, ash, fat, dietary fiber, mineral, and amino acids were evaluated. The values of O. ficus-indica fruits were higher than those of O. humifusa fruits in each morphological feature such as minor axis, major axis, and weight. According to the Hunter color index results, O. humifusa fruits showed higher values of L (lightness) and b (yellowness), whereas O. ficus-indica fruits showed higher value of a (redness). The ${\Delta}E$ value between two samples was 19.80. The O. ficus-indica fruits had higher carbohydrate content and lower content of crude ash than those of O. humifusa fruits. Both samples showed very high dietary fiber contents, and the major minerals were K and Ca. Glutamic acid was the major amino acids in both samples. In free amino acids contents, O. ficus-indica had higher tyrosine and lower glutamic acid level than those of O. humifusa fruits. ${\gamma}$-aminobutyric acid was found in both samples, whereas taurine was found in O. ficus-indica fruits only. Taken together, the morphological features and chemical quality of O. ficus-indica and O. humifusa fruits showed difference although both of them were originated from the same genus.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.428-433
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• 2010

Tomato were stored at different temperatures($10^{\circ}C$, $20^{\circ}C$, room temperature and $30^{\circ}C$) for 5 days. During the storage period, Brix, pH, color, texture, vitamin C, lycopene were analyzed. Brix and pH had a little change. Texture force of tomato decreased with storage time and we could see a softening for tomato stored at $30^{\circ}C$ for 1 day. Addtional, the $L^*$(lightness) and $b^*$(yellowness) decreased and $a^*$(redness) increased with storage time. Addtionally, content of vitamin C increased up to 9.08 mg/100 g~17.82 mg/100 g after 5 days storage according storage temperature, whereas content of lycopene increased up to 3.81 mg/kg~34.56 mg/kg after 5 days storage according storage temperature. Optimal mature temperature for tomato was room temperature.