• Preventive Nutrition and Food Science
• /
• 제16권4호
• /
• pp.364-369
• /
• 2011

Levels of carbon dioxide gas, a metabolite of microbial growth, have been reported to parallel the onset of microbial spoilage and may be used as a convenient index for a packaged food's shelf life. This study aimed to establish a kinetic model of $CO_2$ production from perishable food for the potential use for shelf life control in the food supply chain. Aerobic bacterial count and package $CO_2$ concentration were measured during the storage of seasoned pork meat at four temperatures (0, 5, 10 and $15^{\circ}C$), and their interrelationship was investigated to establish a mathematical model. The microbial growth at constant temperature was described by using model of Baranyi and Roberts. $CO_2$ production from the stored food could be explained by taking care of its yield and maintenance factors linked to the microbial growth. By establishing the temperature dependence of the microbial growth and $CO_2$ yield factor, $CO_2$ partial pressure or concentration in package headspace could be estimated to a limited extent, which is helpful for controlling the shelf life under constant and dynamic temperature conditions. Application and efficacy of the model needs to be improved with further refinement in the model.

• Journal of Biosystems Engineering
• /
• 제24권6호
• /
• pp.479-486
• /
• 1999

A measurement method for the deposition amount of spray, using tracer and spectrophotometer was developed. Food colors was selected as tracer, because it was cheep and easily treatable. Using NIRS(Near Infrared Reflection Spectrophotometer), regression curves between absorbance spectrum and concentration of the tracer were obtained. Yellow food colors showed the peak of spectrum at 452nm, and absorbance of peak showed a tendency to increase as concentration increased. Also, the possibility of concentration control by heating was investigated.

• 한국축산식품학회:학술대회논문집
• /
• 한국축산식품학회 2004년도 제34차 추계 국제 학술대회
• /
• pp.407-411
• /
• 2004

Ohmic heating occurs when an electric current is passes through food, resulting in a temperature rise in the product due to the conversion of the electric energy into heat. The time spent in the thawing is critical for product sterility and quality. The objective of this study is to conduct numerical modelling between the effect of ohmic thawing intensity on PTT(phase transition time) at constant concentration and the effect of matrix concentrations on PTT at constant voltage condition. the stronger ohmic thawing intensity resulted in decreasing the PTT. High ohmic intensity causes short PTT. And the higher gelatin concentration, the faster increment of PTT. A numerical modeling was executed to predict the PTT influenced by the power intensity using exponential regression and the PTT influenced by gelatin concentration using logarithmic regression. Therefore, from this numerical model of gelatin matrix, it is possible to estimate exact values extensively.

• 한국식품영양학회지
• /
• 제21권4호
• /
• pp.492-498
• /
• 2008

This study investigated the quality characteristics of the white pan bread prepared with pomegranate powder. Three different powder concentration levels of 1%, 2% and 3% were added to flour to make the bread. The contents of moisture and crude fat contents of the bread added with to which pomegranate powder was added were lower than that of the control group. However, the ash content was not did not significantly different differ significantly among groups. The pH increased with increasing concentrations of pomegranate powder concentration. The weight of bread increased with increasing concentrations of pomegranate powder concentration, while whereas the volume and baking loss rate of bread concomitantly decreased. In terms of color values, with increase increases in of the concentration of pomegranate powder concentration, induced a reduction in the L value decreased, but and a concomitant increase in the a and b values increased. The water activity in the bread decreased by with increasing pomegranate powder concentration, and was the highest in the control group. In the Upon texture analyzer measurement analysis, the hardness of the bread was shown to increased increase with increases of in the concentration of pomegranate powder concentration, but the springiness decreased. In the With regard to the results of sensory evaluation, the quality of the 1% pomegranate powder bread showed the evidenced the highest in taste, flavor, and overall acceptability. The color, appearance, mouth feel, and texture of the bread decreased with the increasing pomegranate powder content concentrations. From According to the results of this study, the white bread prepared with 1% pomegranate powder content was shown judged to have the best highest quality.

• 한국식생활문화학회지
• /
• 제12권1호
• /
• pp.53-61
• /
• 1997

This study was carried out in order to investigate general characteristics, sugars and organic acids contents of Korean traditional soy sauce, and to find out possibility of high quality soy sauce production in a short period through high concentration soy sauce making. In this study, we prepared three different types of soy sauce, low concentration soy sauce (Chungjang), high concentration soy sauce and Kyupjang, high quality traditional Korean soy sauce. pH of soy sauce were $4.46{\sim}4.90$ and did not show difference among three samples. Titratable acidity, buffering power and total free acid content were the highest value in Kyupjang. Kyupjang showed the highest contents of salt and pure extract. As the ripening period increased, the salt content increased in Chungjang samples, but decreased in Kyupjang. Reducing sugar contents of Kyupjang, high concentration soy sauce and low concentration soy sauce were 1.13%, 0.76% and 0.53%, respectively. Free sugar in soy sauce were analyzed maltose, glucose, galactose and fructose. Total free sugar content was highest in high concentration soy sauce, however, contents of glucose and fructose were higher in Kyupjang than in Chungjang samples. Galactose was the main free sugar in Chungjang, but glucose was in Kyupjang. Among identified volatile organic acid, acetic acid was present in the highest concentration, and volatile organic acid content was highest in the high concentration soy sauce at 150 days. 20 nonvolatile organic acids were detected in Korean traditional soy sauce. Succinic acid, lactic acid and 2,5-pyridine dicarboxylic acid were the main nonvolatile organic acid in soy sauce.

• Preventive Nutrition and Food Science
• /
• 제1권2호
• /
• pp.174-178
• /
• 1996

The content of anserine, taurine, and L-histidine was measured by HPNC in the muscle of mature(670~690g) and juvenile(80~120g) rainbow trout fatmed in Chungsun, Korea. The concentration of anserine and taurine was higher in mature rainbow trout than in juvenile, but that of L-histidine was lower in mature than in juvenile. When measured with the chemiluminescence(CL) assay, anserine and taurine showed very powerful antioxidative activity above physiological concentration rainbow trout. Taurine still showed antioxidative activity below physiological concentration, while anserine showed prooxidative activity below that. L-Histidine was prooxidative dose-dependently. In TBA method, while taurine showed very week antioxidative effect, anserine appeared very powerful antioxidant and L-histidine prooxidant at physiological concentration. There was no synergism between anserine and taurine and anserine inhibited prooxidative effect of L-histidine.

• 한국식품영양학회지
• /
• 제12권2호
• /
• pp.204-208
• /
• 1999

In order to obtain data for use of algin in drink making process solution properties of algin have been investigated at various condition of algin concentration temperature pH and various food additives. At same revolution velosity viscosities of algin were increased as algin concentration raised. Algin solution showed dilatnat type flow in concentration of 0.25% to 0.4% but pseudoplastic type flow in above 0.5% showed dilatant type flow in concentration of 0.25% to 0.4% but pseudoplastic type folw in above 0.5% A maximum viscosity of algin was observed at pH 5.5 and its viscosities were also decreased as the tem-perature increased and heating at 8$0^{\circ}C$ above. Organic acids affected on the viscosity of algin with pH dependently and gel formed in pH below 3.0 Sweetners have no effect to the viscosity of algin. How-ever addition of NaCl and KCL upto 1.0% decreased a little its viscosity and CACl2 MgCl2 and FeCl3 increased the viscosity of algin Glutamic acid decreased the viscosity of algin.

• 한국식품영양학회지
• /
• 제21권4호
• /
• pp.485-491
• /
• 2008

This study investigated the quality characteristics of the white pan breads with garlic powder. Three different powder concentration levels of 1%, 2% and 3% were added to flour to make the breads. The contents of moisture and crude fat of the breads added with garlic powder were lower than that of control group. However, ash content was not significantly different among groups. The pH increased with increasing garlic powder concentration. The weight of breads increased with increasing garlic powder concentration, while the volume and baking loss rate of breads decreased. In color values, with increase of garlic powder concentration, L value decreased, but a and b values increased. The water activity in the breads decreased by increasing garlic powder concentration was the highest in the control group. In the texture analyzer measurement, hardness of the breads increased with increases of garlic powder concentration, but springiness decreased. In the results of sensory evaluation, the quality of the 1% garlic powder breads showed the highest in taste, flavor and overall acceptability. The color, appearance, mouth feel and texture of the breads decreased with the increasing garlic powder content. From the results of this study, the white breads with 2% garlic powder content was shown to have the best quality.

• 한국식품영양과학회지
• /
• 제17권2호
• /
• pp.110-114
• /
• 1988

무우의 소금절이 과정중 소금의 농도별 시간경과에 따른 소금침투와 칼슘의 용출 및 수분의 유출정도를 조사하였다. 또 가정 및 백화점으로부터 수집한 김치중 관능적으로 양호한 김치를 선별하여 그 소금농도를 조사하였다. 가정과 백화점으로부터 수집한 20종의 김치중 짠맛에 대한 관능검사에서 양호한 것은 8종이었고 소금농도는 $1.2{\sim}2.2%$ 범위였다. 무우의 절임시 소금농도를 3, 5 및 10%로 증가시킴에 따라 수분유출과 칼슘의 용출은 더욱 증가되었고 고농도 단시간 절임보다 저농도 장시간 절임이 효과적이었다. 관능검사에 의하여 양호하다고 판정된 소금의 농도까지의 염적시간은 3% 경우는 2시간, 5%는 1시간, 10%는 30분이었다.

• 한국식품조리과학회지
• /
• 제21권1호
• /
• pp.47-52
• /
• 2005

This study aimed to determine inhibitory effect of pathogen growth by adding green tea extracts to some cook-chill foods. For this study, chicken meat salad and pyeonyuk were blended with green tea extracts to different concentrations of 0, 2 and $3\%$ and prepared in a cook-chill system. S. typhimurium in chickien meat salad; Better antibacterial effects of green tea extracts were observed at a $3\%$ concentration, compared with a $2\%$ concentration. Populations of S. aureus in chicken meat salad; antibacterial effects at a $3\%$ concentration became significant from 3days while that at a $2\%$ concentration remained steady throughout the five-day duration. All three testing samples exhibited a decrease in populations of S. aureus during storage. In pyeonyuk, S. aureus counts at a $3\%$ concentration were 7.26 CFU/g on day 3 and declined to 6.61 CFU/g and 6.48 CFU/g on the following days, showing a greater degree of decline than that of a $2\%$ concentration.