• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.446-453
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• 2009

This study was conducted to find condition of improving the quality of peach by using surfacing washing system. The rate of weight loss of A,B groups were showed slower decreasing trend than CT group and the value of soluble solid degree was not different significantly among all groups from the results of stored peach treat with surface washing system of peach in the first experiment. The colory value of surface were increased with increasing storage period in all treatments. Browning pace of A,B groups were slower than control. Emission of carbon dioxide was increased from the results of respiration rate, 6-10 mL/kg/hr $(10^{\circ}C)$ and 32-41 mL/kg/hr $(25^{\circ}C)$. In second experiment with surface washing system of peach, the value of soluble solid was showed with similar value from 10 $Brix^{\circ}$ to 13 $Brix^{\circ}$. The pace of soft rot of EW groups were lower than CT groups from the results of hardness during storage period. The results of colory value was not showed with significant difference in $15^{\circ}C$ and $20^{\circ}C$ storage temperature but changed to browning in EW groups. The moisture contents was from 85% to 90% in all groups. And the count of total microorganism of EW groups were lower than control. Also total coliform of EW groups were negative. In sensory evaluation, washing peach was showed higher value with significant difference in all acceptability.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.28-34
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• 2006

Effects of various surface sterilization and washing methods on sterilization of fresh chicory surface were evaluated. Fresh-cut chicory was washed with tap water for 1 min, 100 ppm chlorinated water, and 3 ppm ozonated water using mechanical washing machine for 3 min, packed with bi-axially oriented polypropylene (OPP 0.04 mm) film, and stored for 3 weeks at 4 and $10^{\circ}C$. Tap water washing resulted in approximately 1 log CFU/g reduction of microbial load, and ozonated water and chlorinated water treatments resulted in additional 2 log CFU/g reduction.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.370-377
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• 2015

The purpose of this study was to obtain data to improve customer orientation by managing emotional labor in foodservice employees. This study investigated the correlation between emotional labor (surface acting, deep acting), job burnout (emotional exhaustion, cynicism), and job engagement (vigor, dedication, absorption) in high school foodservice employees, and how they affect customer orientation. Our survey was administered to 330 school foodservice employees in the Busan area from June 2 to June 27, 2015. A total of 321 questionnaires were used for final analysis. The mean values for deep acting (p<0.01), cynicism (p<0.01), and dedication (p<0.05) significantly according to the position of the emproyees. The mean customer orientation significantly according to employment status (p<0.01) and meal service time (p<0.01). There was positive correlation (p<0.01) between surface acting, and emotional exhaustion cynicism, but negative correlation (p<0.01) between surface acting and vigor, dedication, absorption, and customer orientation. Deep acting had negative correlation (p<0.01) with emotional exhaustion and cynicism, positive correlation (p<0.05) with vigor, dedication, absorption, and customer orientation. Surface acting had negative influences on emotional exhaustion and cynicism, cynicism had negative influences on vigor, dedication, absorption, and customer orientation. Deep acting had positive influences on absorption and customer orientation, absorption had positive influences on customer orientation. Thus, nutrition teacher(dietitian) should educate foodservice employees the positive effects of deep acting to change their surface acting to deep acting, while actively managing internal customers.

• Preventive Nutrition and Food Science
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• v.22 no.1
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• pp.37-44
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• 2017

Sulfur-containing amino acids play important roles in good flavor generation in Maillard reaction of non-enzymatic browning, so aqueous model systems of glucosamine and cysteine were studied to investigate the effects of reaction temperature, initial pH, reaction time, and concentration ratio of glucosamine and cysteine. Response surface methodology was applied to optimize the independent reaction parameters of cysteine and glucosamine in Maillard reaction. Box-Behnken factorial design was used with 30 runs of 16 factorial levels, 8 axial levels and 6 central levels. The degree of Maillard reaction was determined by reading absorption at 425 nm in a spectrophotometer and Hunter's L, a, and b values. ${\Delta}E$ was consequently set as the fifth response factor. In the statistical analyses, determination coefficients ($R^2$) for their absorbance, Hunter's L, a, b values, and ${\Delta}E$ were 0.94, 0.79, 0.73, 0.96, and 0.79, respectively, showing that the absorbance and Hunter's b value were good dependent variables for this model system. The optimum processing parameters were determined to yield glucosamine-cysteine Maillard reaction product with higher absorbance and higher colour change. The optimum estimated absorbance was achieved at the condition of initial pH 8.0, $111^{\circ}C$ reaction temperature, 2.47 h reaction time, and 1.30 concentration ratio. The optimum condition for colour change measured by Hunter's b value was 2.41 h reaction time, $114^{\circ}C$ reaction temperature, initial pH 8.3, and 1.26 concentration ratio. These results can provide the basic information for Maillard reaction of aqueous model system between glucosamine and cysteine.

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.75-84
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• 2011

The aim of this study was to develop a convenient brown sauce product with long shelf life that has similar taste and quality characteristics with sauce used in restaurants. Response surface analysis was carried out to optimize brown sauce. Extracted brown sauce powder was subjected to hot air drying, infrared drying, freeze drying, and spray drying to determine the appropriate drying method for brown sauce manufacturing. The optimum extraction conditions were set by superimposing and reading each reaction surface that satisfied all of the sensory characteristics such as color, smell, taste, concentration, and overall preference level in order to set the optimum conditions for brown sauce production. The optimum extraction conditions for brown sauce were determined to be heating time 30 min, gelatin addition quantity 9.00%, and tomato paste addition quantity 11.25%. Reliability test showed a similar value to the predicted scope when compared to the experimental value obtained under the same conditions as the predicted value according to RSM (response surface methodology), enabling verification of the derived regression formula. Product powder of ideal brown sauce by heating, infrared radiation, freezing, and spray drying and investigate result for functional tests of color, flavor, taste, viscosity, overall acceptability and show highly acceptability on powder by infrared rays and freeze-drying methods. Especially, infrared radiation method resulted in favorable color and flavor values while freeze-drying method produced good taste and viscosity values and high overall acceptability. Therefore, infrared radiation drying method and freeze-drying method to product powder.

• Korean journal of food and cookery science
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• v.28 no.2
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• pp.133-141
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• 2012

$Kochujang$ is a fermented paste originated from in and $Kochujang$ sauce is a nutritionally and functionally improved version of $Kochujang$ with additions of beef and tonic herbal extracts. The optimization of the ingredient ratios in the manufacturing of $Kochujang$ sauce was investigated using central composite design and response surface methodology. The amount of beef ($X_1$) and the amount of tonic herbal extract ($X_2$) were chosen as the independent variables. The dependent variables consisted of the properties and sensory evaluation scores The examined physicochemical properties included water activity, pH, color, viscosity, and soluble solids. The sensory evaluation attributes were color, flavor, taste, texture, and overall acceptability. Among them, the selected dependent variables were the sauce viscosity ($Y_1$) and the overall acceptability ($Y_2$) of the sauce. The optimal conditions for the independent variables were $X_1$= 9.7% and $X_2$= 14.1%. In addition, the predicted values of the multiple response optimal conditions were $Y_1$= 331000 (cP) and $Y_2$= 7.1 (points), and the actual experimental values were $Y_1$= 3316667 (cP) and $Y_2$= 7 (points).

• Food Science of Animal Resources
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• v.33 no.1
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• pp.31-38
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• 2013

If the time-temperature indicator (TTI) experienced a different temperature than the accompanied packaged food, influenced by heat transfer between the TTI, package, and ambient air, TTI would incorrectly predict the food quality changes with temperature. Temperature distributions of a finite slab with different sizes, representing beef packaged with TTI, were estimated by the finite element method (FEM). The thermal properties of the beef and TTI, such as heat capacity, density, and heat conductivity, were estimated from the relevant equations using their chemical compositions. The FEM simulations were performed for three cases: different locations of TTIs on the beef, different thicknesses of beef, and non-isothermal conditions of ambient air. The TTIs were mounted in four different locations on the beef. There was little difference in temperature between four locations of the TTI on the package surface. As the thickness of the slab increased, the temperature of the TTI changed faster, followed by the corner surface, as well as middle and bottom parts, indicating the possible error for temperature agreement between the TTI and the slab. Consequently, it was found that any place on the package could be selected for TTI attachment, but the package size should carefully be determined within a tolerable error of temperature.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.148-155
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• 2009

The purpose of this study was to find new applications for Rubus coreanus and to produce new products. Jelly prepared with Rubus coreanus was studied and analyzed with regard to its composition, rheology and sensory evaluation. The technique of response surface methodology was used to analyze the results, which showed 16 experimental points including 2 replicates for Rubus coreanus juice, gelatin and sucrose. Rheological characteristics such as lightness, redness, yellowness and hardness, springness, chewiness and gumminess were shown to be significant, and these were mostly influenced by the content of Rubus coreanus juice. Significant sensory characteristics such as color, flavor, transparency, taste and the overall quality were also found to be greatly influenced by Rubus coreanus juice and gelatin in general. Based on the overlapping categories of factors that satisfied all sensory categories, the maximally optimized point was taken as the middle point. This value was determined to be 43.28 g of Rubus coreanus juice and 9.19 g of gelatin for every 140.00 g of sucrose.

• Journal of the Korean Society of Food Culture
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• v.26 no.6
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• pp.717-726
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• 2011

Response surface methodology (RSM) was performed in order to determine the optimal mixing conditions of different amounts of egg and sugar for the preparation of soybean pudding. The experiments were designed according to a central composite design by designating whole egg and sugar content as independent variables. Meanwhile, sweetness, Commission Internationale de I'Eclairage (CIE) color parameters (L*, a* and b* values), hardness, cohesiveness, springiness, and gumminess were response variables. Overall optimization, conducted by overlaying the contour plots under investigation, was able to determine the optimal range of dependent variables within which the 14 responses were simultaneously optimized. The point chosen as a representative of this optimal region corresponded to 50.00 g of whole egg and 31.66 g of sugar. Under these conditions, the model predicted L* value=80.03, a* value=-5.44, b* value=27.86, sweetness=21.23 ($^{\circ}Brix$), hardness=$25.45{\times}10^5$ (dyne/$cm^2$), cohesiveness=67.90 (%), springiness=46.20 (%), and gumminess=12.71 (g).

• Korean journal of food and cookery science
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• v.26 no.1
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• pp.54-61
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• 2010

This study was performed to determine the optimal manufacturing conditions adding green laver, which has a rich aroma and unique taste, to Sulgidduk. The variables in green laver Sulgidduk production were amounts of green laver powder and water. Six sensory characteristics were used for sensory evaluations, including color, green laver flavor, green laver taste, moistness, softness, and elasticity. The optimal amounts of the powder and water were found to be 6.84 g for green laver powder and 31.08 g for water, satisfying a target sensory score (7.0/9.0) according to a response surface method. Sulgidduk with these optimal amounts of green laver and water was tasted by 118 consumers and showed a high acceptability score (6.94). Older consumers ($\geq$30 years old) preferred the color and flavor of green laver significantly more than younger consumers ($\leq$29 years old) did (p<0.01). Color analysis results of green laver Sulgidduk were significantly different in brightness, redness, and yellowness from those of Sulgidduk (control)(p<0.01). Texture analysis scores of green laver Sulgidduk were significantly lower than those of Sulgidduk (control) in hardness, adhesiveness, springiness, cohesiveness, gumminess, and chewiness, and they were significantly different in adhesiveness and chewiness (p<0.05).