• Korean Journal of Community Nutrition
• /
• v.19 no.3
• /
• pp.250-257
• /
• 2014

Objectives: This study examined the impact of perceived volume on satiety using normal rice bowl, diet rice bowl and small rice bowl. Methods: Thirty-six normal weight college female students participated in this study once a week for 3 weeks. Three hundred grams of fried rice in a normal rice bowl (1st week), 300 g of fried rice in a diet rice bowl (2nd week), and 300 g of fried rice in small rice bowl (3rd week) were served to the same participants over three consecutive weeks. After each lunch, the consumption volume of fried rice and the satiety rate were measured. Results: The consumption volume of fried rice was 248 g (414.5 kcal) with a normal rice bowl, 254 g (429.8 kcal) with a diet bowl, and 270 g (456.8 kcal) with a small rice bowl. Results showed that the subjects who were eating from the small rice bowl ate more fried rice (p<0.05) than eating from the normal rice bowl and diet rice bowl. However, the satiety rate of fried rice in a diet rice bowl was significantly higher than that of normal rice bowl and small rice bowl (p<0.05). The five point scale of perceived volume on fried rice served normal rice bowl, diet rice bowl and small rice bowl were 2.4, 4.0 and 2.1. Conclusions: The visual cue plays a critical role in determining satiety and that perceived volume is perhaps more important than actual volume of consumed food in determining the level of fullness.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.12
• /
• pp.4161-4164
• /
• 2012

Density functional MO calculations for the methylsilole anion of $[C_4H_4SiMe]^-$ and methylgermole anion of $[C_4H_4SiMe]^-$ at the B3LYP (full)/6-311+$G^*$ level (GAUSSIAN 94) were carried out and characterized by frequency analysis. The ground state structure for the methylsilole anion and methylgermole anion is that the methyl group is pyramidalized with highly localized structure. The difference between the calculated $C_{\alpha}-C_{\beta}$ and $C_{\beta}-C_{\beta}$ distances are 9.4 and 11.5 pm, respectively. The E-Me vector forms an angle of $67.9^{\circ}$ and $78.2^{\circ}$ with the $C_4E$ plane, respectively. The optimized structures of the saddle point state for the methylsilole anion and methylgermole anion have been also found as a planar with highly delocalized structure. The optimized $C_{\alpha}-C_{\beta}$ and $C_{\beta}-C_{\beta}$ distances are nearly equal for both cases. The methyl group is located in the plane of $C_4E$ ring and the angle between the E-Me vector and the $C_4E$ plane for the methylsilole anion and methylgermole anion is $2.0^{\circ}$ and $2.3^{\circ}$, respectively. The energy difference between the ground state structure and the transition state structure is only 5.1 kcal $mol^{-1}$ for the methylsilole anion. However, the energy difference of the methylgermole anion is 14.9 kcal $mol^{-1}$, which is much higher than that for the corresponding methylsilole monoanion by 9.8 kcal $mol^{-1}$. Based on MO calculations, we suggest that the head-to-tail dimer compound, 4, result from [2+2] cycloaddition of silicon-carbon double bond character in the highly delocalized transition state of 1. However, the inversion barrier for the methylgermole anion is too high to dimerize.

• Korean Journal of Agricultural Science
• /
• v.47 no.2
• /
• pp.255-262
• /
• 2020

The aim of this study was to investigate the growth performance between two different crossbred strains of Korean native chickens denoted as 1E and 2E with a white semibroiler (LL) from hatch to d-84 post-hatch. A total of 450 one-day-old chicks were randomly distributed into cages which included 15 replicate cages each for 1E and 2E with 9 replicate cages for LL. A three phase feeding program was used as a starter (Day 1 - 35; crude protein [CP] 20.3%; metabolizable energy [ME] 3,059 kcal·kg^-1), grower (Day 36 - 56; CP 18.6%; ME 3,123 kcal·kg^-1) and finisher (Day 57 - 84; CP 16.7%; ME 3,187 kcal·kg^-1). The results revealed that LL had a higher (p < 0.05) BW during d-8 to d-84 compared with the other two cross breed groups. A higher (p < 0.05) ADG was observed from the LL during the entire period except from d-1 to d-14 and d-71 to d-84 when compared with 1E and 2E. Shank length did not vary (p > 0.05) between the strains, despite LL having a SL that was 2.86% higher (p < 0.05) when compared with the other strains from d-15 to d-21 post-hatch, and 1E had a SL that was 2.28% (p < 0.05) higher when compared with the other strains during the first week of the experiment.

• Korean Journal of Food Science and Technology
• /
• v.21 no.5
• /
• pp.601-605
• /
• 1989

Water absorption of the major kernels(7 and 10mesh sizes) of naked barley differing in pearling degrees at $25-50^{\circ}C$ was investigated. The time to reach equilibrium moisture content was reduced by half upon removal of over 20% of the outer layer of the kernel. Water absorption rate and diffusion coefficient of naked barley of 5% pearling degree at $40^{\circ}C$ were faster about 1.5 and 2.8 times than those of unpearled one. The activation energy of hydration for unpearled naked barley was 11.5kcal/mole, which was decreased by approximately 0.4kcal/mole upon increasing the pearling degree by 5%.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.6
• /
• pp.785-791
• /
• 1993

Kinetic studies were performed to investigate free-fructose content change in rice during storage. The rice was stored at various water activities(0.44, 0.52, 0.65 and 0.75) and at fluctuating temperature($30/50^{\circ}C$) over period of 22 weeks. At early stage of storage free-furctose content increased by zero-order reaction, whereas at later stage, it decreased by first-order reaction. The reaction rates were positively related to water activity and/or temperature during storage. Activation energies calculated at range of aw 0.44~0.75 were found to be 10.76~19.56kcal/mole and 4.53~8.40kcal/mole, for the period of increase and decrease in the free-fructose contents, respectively. The shelf-life assessed at $25^{\circ}C$ was found to be 252(aw 0.44), 212 (aw 0.52), 193(aw 0.65) and 162(aw 0.75) days.

• Korean Journal of Food Science and Technology
• /
• v.29 no.6
• /
• pp.1089-1093
• /
• 1997

The physicochemical properties of erythritol were examined by measuring water absorption, solubility, water activity, heat stability, and viscosity compared to those of sucrose, xylitol, sorbitol and fructo-oligosaccharide. Erythritol showed the lowest water absorption and the highest water activity reducing capacity. In the solubility test of sweeteners, the saturation concentration of erythritol at $20^{\circ}C$ was 35.8%, which was the lowest solubility. Caramelization test and Maillard reaction test showed that erythritol was stabler than sucrose in heat treatment, while fructo-oligosaccharide showed the strongest reaction. The viscosity of erythritol was similar to that of other sweeteners at the same concentration (10%, 30% w/w). The viscosity of sweeteners increased exponentially with increasing concentration but decreased with increasing temperature following Arrhenius equation. The activation energy for flow of 30% erythritol solution was estimated to be 10.8 kcal/g mol.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.6
• /
• pp.1760-1767
• /
• 2008

In this study, we analyzed the physical and chemical properties such as proximate analysis, ultimate analysis, heating values, and thermogravimetric analysis for the organic sludges discharged from an industrial complex in Ulsan. The average water, combustible, and ash content of organic sludges were 72.9, 18.5, and 8.6%, respectively. And according to the ultimate analysis of organic sludges, the C, O, H, N, and S compositions were 33.9, 26.4, 4.4, 4.4, and 0.6%, respectively. According to the results of investigating the lower heating values, 6 sludges were on the range of $1,500{\sim}2,000\;kcal/kg$ and 4 sludges were on the range of over 2,000 kcal/kg. Therefore, these 10 sludges could be directly applied to industries which try to use the energy by direct incineration.

• Nutrition Research and Practice
• /
• v.12 no.3
• /
• pp.243-250
• /
• 2018

BACKGROUND/OBJECTIVES: This study examined the effect of nutrition labeling formats on parents' food choices for their children at different restaurant types. SUBJECTS/METHODS: An online survey was conducted with 1,980 parents of children aged 3-12 years. Participants were randomly assigned to fast food or family restaurant scenarios, and one of four menu stimuli conditions: no labeling, low-calorie symbol (symbol), numeric value (numeric), and both low-calorie symbol and numeric value (symbol + numeric). Participants selected menu items for their children. Menu choices and total calories were compared by nutrition labeling formats in each type of the restaurant. RESULTS: Low-calorie item selections were scored and a two-way analysis of variance (ANOVA) was conducted for an interaction effect between restaurant and labeling type. In the fast food restaurant group, parents presented with low-calorie symbols selected the lowest calorie items more often than those not presented with the format. Parents in the symbol + numeric condition selected significantly fewer calories (653 kcal) than those in the no labeling (677 kcal) or numeric conditions (674 kcal) (P = 0.006). In the family restaurant group, no significant difference were observed among different labeling conditions. A significant interaction between restaurant and labeling type on low-calorie selection score (F = 6.03, P < 0.01) suggests that the effect of nutrition labeling format interplays with restaurant type to jointly affect parents' food choices for their children. CONCLUSIONS: The provision of easily interpretable nutritional information format at fast food restaurants may encourage healthier food choices of parents for their children; however, the effects were negligible at family restaurants.

• Korean Journal of Food Science and Technology
• /
• v.23 no.3
• /
• pp.355-359
• /
• 1991

Effects of temperature and pH on thermal degradation of monosodium glutamate(MSG) were investigated during heating of 2% MSG solution at $100{\sim}200^{\circ}C\;and\;pH\;4{\sim}9$. The results showed that the degradation of MSG was very significantly affected by heating temperature and pH. Three hours of heating at $pH\;4\;and\;120^{\circ}C$ resulted appr. 73% MSG degradation while 3 hours at $100^{\circ}C$ decreased only 12%. The comparison study of initial rate of MSG degradation and degradation rate constants showed the highest degradation rate and rate constant and low values in the range of $pH\;6{\sim}8{\sim}$. The values of activation energy calculated from linear relationship of rate constants and 1/T were 18.3 and 9.2 kcal/mole for pH 4 and 5, respectively.

• Korean Journal of Agricultural Science
• /
• v.45 no.4
• /
• pp.733-739
• /
• 2018

This study was conducted to investigate the growth performance between six different Korean crossbred native chickens. A total of 312 one-day-old male chickens from the same paternal line with six different maternal lines were allocated into six groups (1A, 2A, 3A, 4A, 5A, and 6A) to give four replicate cages (13 birds per cage). Corn soybean meal based diets were provided as a starter (0 - 5 weeks: 20% crude protein [CP] and 3,050 kcal/kg metabolizable energy [ME]), grower (5 - 8 weeks: 18% CP, 3 and 100 kcal/kg ME) and finisher (8 - 12 weeks: 17% CP and 3,150 kcal/kg ME) diet. Chickens were able to access their respective feed and water ad libitum. In week 2, 2A had a lower body weight (p < 0.05) than that of the other groups. In contrast, in weeks 4 and 8, 2A had a higher body weight (p < 0.05). Similarly, in week 6, 2A had a higher body weight (p = 0.76) than that of the others. However, no difference (p > 0.05) was observed in the body weight after week 10. Meanwhile, 2A had a lower feed conversion ratio (FCR) than that of the other groups (p < 0.05) and a higher average daily feed intake (ADFI; p < 0.05) compared to the other groups in week 6. In conclusion, crossbred 2A had a lower growth performance in week 2; however, in weeks 4 and 6, 2A had a higher growth performance than that of the other groups. Based on this conclusion, we can use those results as a basis for further study.