• Journal of Ginseng Research
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• v.5 no.1
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• pp.8-23
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• 1981

Color is one of the most important quality factors of red ginseng (Hong-sam) which is processed from fresh ginseng (Panax ginseng C. A. Meyer). Therefore, a study of characteristics of browning mixtures of aqueous fresh ginseng extracts, factors which accelerate the browning of the aqueous extracts, and the antioxidant activity of the browning mixtures may contribute to the improvement of the color and other quality of red ginseng and other ginseng products such as ginseng extracts. In the present study, factors which affect the Maillard-type browning reaction of aqueous extracts of fresh ginseng roots were investigated firstly by adding various concentrations (0.001-0.5M) of arginine or glucose solutions, by varying the browning reaction temperatures and durations. Secondly, some characteristics such as brown color intensity, amounts of water-soluble and ether-soluble extracts, amounts of non-dialyzable materials, pH, viscosity, and reactivity with 2,2'- diphenyl -1 - picrylhydrazyl and antioxidant activity of the browning mixtures of the aqueous fresh ginseng extracts with small amounts of 0.1 M arginine, 0.1 M glucose, and distilled water at various browning temperatures and reaction time were studied. The results of the present study are as follows. 1. Color intensity (absorbance at 470 nm) of the browning mixtures was increased by adding various concentrations of arginine solution to the fresh ginseng extract, but the addition of the same amount of glucose solution did not increase the color intensity. 2 The amounts of water- or ether-soluble extracts, amounts of non-dialyzable materials were slightly greater in case of the browning mixtures of the fresh ginseng extract with 0.1M arginine solution than in case of the browning mixtures of the fresh ginseng extract with the same amount of 0.1 M glucose solution. In the process of the browning reaction, the pH of the browning mixtures of the fresh ginseng extract with 0.1 M arginine solution decreased slightly, while that of the browning mixtures with 0. 1 M glucose solution was almost constant. 3. The color intensity (absorbance at 470 nm) of the browning mixtures of the fresh ginseng extract with 0.1 M arginine or 0.1 M glucose solutions did not correlate well with the reducing power or the antioxidant power of the browning mixtures. The antioxidant activity of 90% ethanol extracts from the earlier stages of the browning mixtures of the fresh ginseng extract with the arginine solution was almost comparable to that of the 90% ethanol extracts from the later stages of the corresponding browning mixtures. The browning mixtures of only the fresh ginseng extract or of the fresh ginseng extract with the glucose solution showed considerable antioxidant activity, although both showed less brown color intensity than the fresh ginseng extract with he arginine solution.

• Preventive Nutrition and Food Science
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• v.12 no.4
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• pp.284-288
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• 2007

Effect of aqueous chlorine dioxide $(ClO_2)$ treatment on the quality change of fresh ginseng during storage was examined. Fresh ginseng samples were treated with 0, 50, and 100 ppm of $ClO_2$ solution, respectively, and stored at $4^{\circ}C$. Microbiological data of the fresh ginseng after $ClO_2$ treatment revealed that the populations of total aerobic bacteria, and yeast and mold were significantly reduced with the increase of $ClO_2$ concentration. In particular, the populations of total aerobic bacteria, and yeast and mold in the fresh ginseng decreased by 2.1 and 1.2 log CFU/g at 100 ppm $ClO_2$ treatment, respectively. Aqueous $ClO_2$ treatment improved the color of the fresh ginseng during storage, but there was no significant difference in weight loss during storage among treatments. Sensory evaluation results represented that the qualities of the fresh ginseng treated with aqueous $ClO_2$ during storage were better than those of the control. These results clearly indicate that aqueous $ClO_2$ treatment could be useful in decreasing the microbial growth and extending the shelf life of fresh ginseng.

• Korean Journal of Optics and Photonics
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• v.11 no.5
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• pp.312-316
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• 2000

Vole lllvesnguted the surface roughness charactenstics of the super~polished mirror substrate made by bowl-feed technique. in comparison with the case of fresh-feed technique. Fresh-feed techmque and bowl-feed technique were tried lor substrate surface polishing, and the surface roughne~s was estimated by phase-measunng interferometry. l11e slilface roughness of the substrate after bowl-feed procedure was Improved approxImately three times as fine as that after fresh-feed procedure. and tbe nns roughness of less than $0.5\AA$ and up to $0.3\AA$ at its best was obtained for the bowl-feed procedure. The surface roughness changes by (he bowl-feed technique. compated with tbe fresh-feeclleclmique. were analyzed witb tbe help of both 1 -dimensional roughne,>s profde and rougbness amplItude spect1U1l1 of the polished substrate, whIch ascertained that the final polishing partIcle size of the bowl-feed ptocedure was much smaller than that of the fresh~feed procedure. edure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.12
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• pp.1218-1226
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• 2004

This paper presents thermal behaviors and performances of a fresh air load reduction system by using earth tube system combined with air-heated solar collector. The earth tube system reduces a fresh air load by heat exchange with soil throughout the year. In the previous experimental research, it was clarified that the earth tube system was very useful as a fresh air load reduction system. However, since outlet temperature of the fresh air which was heated by earth tube system was below 15$^{\circ}C$ in winter, it is not suitable to introduce the fresh air into the place of residence directly. Therefore, a simulation model using the simple heat diffusion equation was used to examine a rising effect of outlet air temperature in winter by combining with air-heated solar collector. An improvement of annual performance by control of operation is also quantitatively examined. In conclusion, it is confirmed that its performance is improved by control of operation throughout the year and outlet air temperature rose by combining with air-heated solar collector.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.829-834
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• 2018

The objective of this study was to determine the minimum enrichment time for different types of food matrix (pork, beef, and fresh-cut lettuce) in an effort to improve Escherichia coli detection efficiency. Fresh pork (20 g), beef (20 g), and fresh-cut lettuce (20 g) were inoculated at 1, 2, and 3 Log CFU/g of Escherichia coli. Samples were enriched in filter bags for 3 or 5 h at $44.5^{\circ}C$, depending on sample type. E. coli cell counts in the samples were enriched in E. coli (EC) broth at 3 or 5 h. One milliliter of the enriched culture medium was used for DNA extraction, and PCR assays were performed using primers specific for uidA gene. To detect E. coli (uidA) in the samples, a 3-4 Log CFU/mL cell concentration was required. However, E. coli was detected at 1 Log CFU/g in fresh pork, beef, and fresh-cut lettuce after 5, 5, and 3-h enrichment, respectively. In conclusion, 5-h enrichment for fresh meats and 3-h enrichment for fresh-cut lettuce in EC broth at $44.5^{\circ}C$, and PCR analysis using uidA gene-specific primers were appropriate to detect E. coli rapidly in food samples.

• Journal of Agricultural Extension & Community Development
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• v.24 no.4
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• pp.249-264
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• 2017

Modeling the consumer demand of fresh meat requires its distinct feature which other types of food product does not have. Most of the fresh meat products are likely to be unbranded, bought on a weight basis and affected by macro shocks such as seasonality, holiday effect and the disease incidence. Furthermore, consumers tend to purchase multiple categories of fresh meat in a week. Therefore, we apply a multiple discrete/continuous model on fresh meat consumption data to study the effect of macro shocks on fresh meat sales as well as of price change. As a result shows, Each fresh meat is relatively more likely to be bought in peak season of each fresh meat compared with imported pork which is set as a 'reference category' in this analysis. For clarity of the effect of disease incidence, we perform further analysis regarding the effect of livestock disease on fresh meat purchase probability. It shows that the avian flu in 2014 has strong negative impact on the purchase probability of chicken and the foot-and-mouth disease has negative impact on the purchase probability of pork and beef for part of outbreak periods.

• The Journal of Fisheries Business Administration
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• v.49 no.2
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• pp.21-35
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• 2018

Squid is a popular seafood in Korea. However, since the 2000s, the squid production has been declining. The unstable supply of the squid products may cause price fluctuations of fresh and chilled squid. These price fluctuations may be relatively more severe than them of other commodities, because the fresh and chilled squid can not be stored for a long period of time. Thus, this study analyzes the structural characteristics of price volatility and price asymmetry of fresh squid based on off-diagonal GARCH model. Data used to analysis of this study are daily wholesale and retail prices of fresh squid from January 1, 2006 to December 31, 2016 provided in the KAMIS. As theoretical approaches of this study, first of all, the stability of the time series is confirmed by the unit root test. Secondly, the causality between distribution channels is checked by the Granger causality test. Thirdly, the VAR model and the off-diagonal GARCH model are adopted to estimate asymmetry effect and price volatility spillover between distribution channels. Finally, the stability of the model is confirmed by multivariate Q-statistic and ARCH-LM test. In conclusion, fresh squid is found to have shock and volatility spillover between wholesale and retail prices as well as its own price. Also, volatility asymmetry effect is shown in own wholesale or retail price of fresh squid. Finally, this study shows that the decrease in the fresh squid retail price of t-1 period than the increase in the t-1 period has a greater impact on the volatility of the fresh squid wholesale price in t period.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.495-502
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• 2020

Processing fresh produce into fresh-cut products increases the risk of bacterial growth and contamination by breaking the exterior barrier of produce. Our objective in this study was to develop predictive models of Listeria monocytogenes in the fresh-cut salad, fresh-cut pineapple, and frozen mango. Predictive growth and survival models were developed to predict the change of L. monocytogenes populations in the fresh-cut salad (4, 10, 12, 13, 17, 25, and 36℃), fresh-cut pineapple (4, 10, 17, 25, 30, and 36℃), and frozen mango (-2, -10 and -18℃) as a function of temperature. The growth of L. monocytogenes in fresh-cut salad and pineapple was observed at above 13℃ and 10℃, respectively. The growth of L. monocytogenes in pineapple was faster than in salad. The delta value of L. monocytogenes in frozen mango increased as the storage temperature decreased. The results indicate that L. monocytogenes behave differently according to the physicochemical properties of fresh-cut fruits and vegetables. Since L. monocytogenes grow and survive well in refrigerated and frozen conditions, management programs and preventive controls for the processing of fresh-cut produce should be effectively implemented to enhance the safety of fresh-cut fruits and vegetables at retail markets.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.649-654
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• 2010

This study investigated the recognition of and preference for consumer root vegetables for the improvement of fresh-cut root vegetable quality. The questionnaires consisted of questions on general preference, purchasing locations and quality factors. Answers to 286 questionnaires were analyzed both descriptively and quantitatively using SPSS for Windows (Version 14.0). The principal results were as follows: 37% of the respondents preferred potatoes to other root vegetables; 52% purchased at wholemarket. Most consumers preferred fresh-cut root vegetables; 56% were un-satisfied with fresh-cut vegetables quality as high quality agents. The most considered factor in purchasing fresh-cut root vegetables was shape/appearance.

• Structural Engineering and Mechanics
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• v.57 no.3
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• pp.425-439
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• 2016

This paper deals with the behavior of fresh concrete that is under vibration using mass-spring model (MSM). To this end, behaviors of two different full scale precast concrete molds were investigated experimentally and theoretically. Experiments were performed under vibration with the use of a computer-based data acquisition system. Transducers were used to measure time-dependent lateral displacements at some points on mold while mold is empty and full of fresh concrete. Analytical modeling of molds used in experiments were prepared by three dimensional finite element method (3D FEM) using software. Modeling of full mold, using MSM, was made to solve the problem of dynamic interaction between fresh concrete and mold. Numerical displacement histories obtained from time history analysis were compared with experimental results. The comparisons show that the measured and computed results are compatible.