• Korean Journal of Food Science and Technology
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• v.6 no.3
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• pp.177-184
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• 1974

File fish Navodon modestus was dehydrated in cabinet type hot-sir drier at $48-50^{\circ}C$ for 11 hours and also yellowfin puffer Fugu xanthopterum was dried in open air at $26-28^{\circ}C$ for 30 hours. Nucleotides and their related compounds were collected by extraction with cold perchloric acid and their amounts were determined by anion exchange column chromatography. The contents of ADP, IMP, ATP and hypoxanthine in fresh file fish muscle were 22.9, 12.1, 4.9, and 3.2 ${\mu}mole/g,$ dry wt. respectively. AMP and inosine were 0.9 ${\mu}mole/g,$ dry wt. equally. In fresh yellowfin puffer muscle, the contents of ADP, ATP, AMP, inosine and hypoxanthine were 25.6, 2.4, 1.6, 0.3, 0.6, and 0.4 ${\mu}mole/g,$ dry wt. respectively. In the case of file fish, ADP and ATP tended to degrade rapidly during hot-air dehydration. The contents of IMP were decreased slightly while AMP and inosine were increased. And another case of yellowfin puffer, ADP also tended to degrade rapidly during sun drying while AMP, IMP, inosine and hypoxanthine were increased. Especially, in both case of file fish and yellowfin puffer, inosine was increased twenty five and thirty five times during drying respectively.

• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.169-173
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• 1973

Secondary amines and nitrites in various daily foods have been known as the precursors of potent carcinogenic nitroso compound produced in the human stomach when they were ingested simultaneouly in high concentration. In this report, the amounts and distribution of secondary amines and nitrites in Korean daily foods, kim-chi, fishes, fish eggs, sausages, canned fish foods and fish sauces (salted fish) were studied.Nitrite contents were low in most subjected foods except in sausages. Secondary amines showed low contents in kim-chi, fishes, but high in fish sauces, fish eggs and canned fish foods. The result of this study suggested that the possible formation of carcinogenic nitrosamines during manufacturing, storage and cooking of all Korean foods should be studied.

• Korean journal of food and cookery science
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• v.26 no.2
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• pp.198-205
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• 2010

In this study, the effect of added cashew nuts on the quality characteristics of pound cake were investigated. The weight and volume of the cake increased with the addition of cashew nuts concentration, whereas the dough yield and baking loss decreased. Furthermore, the hardness, penetration and, degree of retrogradation significantly decreased during storage with the addition of cashew nuts. As the cashew concentration was increased, the lightness and redness values of the crumb decreased and the yellowness values increased. In terms of sensory evaluation, when compared to the control group, the cashew nuts pound cake was superior in taste, flavor, chewiness and overall acceptability.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.122-126
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• 2007

Expenditure on meat and meat products has been increased in Korea due to the increase of income and the change of diet. From raising farm animals to eating the meat, various hazardous elements can make their ways into the meat and meat products. Recently the issues on food safety and hygiene are drawing a lot of attention, and the current system for managing the safety of foods is still needed to be improved. This survey was aimed to monitor the current situation of country-of-origin labels and hygiene for the meat markets at 4 regions Korea. The survey was performed by collecting samples from whole- sale and retail stores in the nation, which were selling beef. The markets were divided into groups as to territory and the size of the market (Large size, Medium size, and Small size). In terms of size distribution, small butcher shops occupied the highest percentage. On the itemized suitability test of unpacked and packed beef, all the market of 4 regions showed good agreements. However, such labels indicating the methods of cooking and storage were not properly posted on the products. Especially for Ho-nam region, corrections are needed. The results of monitoring sanitation conditions for the butcher shops at 4 regions in Korea showed relatively low suitability. Especially, there were serious lack of knowledge about wearing the sanitation clothing, caps, and shoes. The problem with food safety is so complicated that producer, consumer, food manufacturer, the press, the government, and scholar should solve altogether. It is necessary to educate farmers, food handlers, consumers, etc. and provide them with an accurate information and knowledge.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.229-237
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• 2009

This study was conducted to compare the quality of the pork from finishing pigs that were fed diets containing different levels of methyl sulfonyl methane (MSM). A total of 135 crossbred pigs $(Landrace{\times}Yorkshire{\times}Duroc)$ were fed either with a control commercial diet or the control diet supplemented with 300- and 500-ppm MSM for 158d. The pigs were slaughtered at approximately 110kg live weight and were transported to the local slaughterhouse for electrical stunning followed by exsanguination. After the slaughter, the pork muscles were dissected from each carcass, placed in wrap package bags, and stored for 8d at $4^{\circ}C$. The TEARS values of the pigs that were fed MSM diets were significantly lower (p<0.05) compared with those of the pigs that were fed with non-supplemented diets. The Na, Mg, and Ca contents of the dietary MSM were significantly lower (p<0.05) than those of the non-supplemented diets, but the Fe, Cu, and Zn contents of the dietary MSM were significantly higher (p<0.05) than those of the non-supplemented diets, and the increased level of MSM supplementation resulted in higher sulfur contents. There was no difference among the diets in terms of amino acid content. The dietary supplementation with MSM, however, led to increased saturated fatty acid and decreased unsaturated fatty acid (%) in the pork muscles (p<0.05). The sensory panelists recorded greater marbling and overall acceptability scores in the samples with 500-ppm-MSM dietary supplementation (p<0.05). These data suggest that supplementing pig diets with MSM can improve the quality of the pork and can enhance the eating quality because the sensory panels found that the pork from pigs that were fed an MSM-supplemented diet had better sensory characteristics.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.220-228
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• 2009

This study was conducted to determine the preblending effect of curing agents on the characteristics of mechanically deboned chicken meat (MDCM), including the pH, water-holding capacity (WHC), and stability under refrigeration conditions. MDCM was preblended with different curing agents [NaCl, 0.75 or 1.5%; sodium tripolyphosphate (STPP), 0.25 or 0.5%; ascorbic acid, 250 or 500 ppm; sodium nitrite, 75 or 150 ppm] and were stored at $4^{\circ}C$ overnight. The preblending of NaCl was found to have improved the WHC and emulsion stability; STPP was found to have improved the pH, WHC, and emulsion stability; and ascorbic acid or sodium nitrite did not affect the pH, WHC, and emulsion stability. The addition of ascorbic acid or sodium nitrite, however, decreased the 2-thiobarbituric acid (TBA) and volatile basic nitrogen (VBN) values of the preblended MDCM through the antioxidizing properties. The mixing effects of different curing agents on MDCM were also evaluated with nine different conditions. Among the treatments, the mixture of NaCl and STPP improved the WHC and emulsion stability due to the increased solubility of salt-soluble protein in the preblended MDCM. The mixture of NaCl, STPP, and ascorbic acid increased the pH, WHC, and emulsion stability, but the mixture of NaCl, STPP, ascorbic acid, and sodium nitrite improved the WHC, emulsion stability, and redness of the surface color with improved storage stability due to the decreased VBN and TBA values. As a result, the mixture of 1.5% NaCl, 0.5% STPP, 500 ppm ascorbic acid, and 75 ppm sodium nitrite showed the best properties as curing agents for MDCM preblending.

• Applied Biological Chemistry
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• v.32 no.2
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• pp.104-108
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• 1989

A 2.5 ton scale of solar energy concentration blast-grain circulation dryer (SECD) was developed in order to shorten the drying time without damaged paddy. Comparative experiments were carried out on performance, drying efficiency, consistency in moisture content, milling recovery, grade of milled rice, and energy requirement and cost against all that of in-bin drying and storage (IBDS) method. The experiments were performed using mixture of several rice varieties of Tongil type(Japonica-Indica breeding type) under the autumn weather in Korea. The circulating air temperature inside SECD was $4{\sim}5^{\circ}C$ higher than that of IBDS. The moisture content of the paddy during the drying period in SECD was uniform while substantially varied in upper, middle or bottom layer in IBDS. By SECD, 24% initial moisture content of paddy was reduced to 15% after only 3 days of drying as compared to 14 days at IBDS. The percentage of cracked kernels in upper, middle and bottom layers in IBDS was 6, 6 and 12%, respectively, whereas 7% in all layers in SECD. Both types of dryers did not significantly affect the milling recovery of dried paddy and grade of milled rice. Energy requirement of SECD(28.8Kw/2.5ton) for paddy drying was much less than that of IBDS(108Kw/2.5ton).

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.69-75
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• 2006

Improper disposal of petroleum and spills from underground storage tanks have created large areas with highly toxic contamination of the soil and groundwater. Methyl tert-butyl ether (MTBE) is widely used as a fuel additive because of its advantageous properties of increasing the octane value and reducing carbon monoxide and hydrocarbon exhausts. However, MTBE is categorized as a possible human carcinogen. This research investigated the Modified Photo-Fenton system which is based on the Modified Fenton reaction and UV light irradiation. The Modified Fenton reaction is effective for MTBE degradation near a neutral pH, using the ferric ion complex composed of a ferric ion and environmentally friendly organic chelating agents. This research was intended to treat high concentrations of MTBE; thus, 1,000 mg/L MTBE was chosen. The objectives of this research are to find the optimal reaction conditions and to elucidate the kinetic and mechanism of MTBE degradation by the Modified Photo-Fenton reaction. Based on the results of experiments, citrate was chosen among eight chelating agents as the candidate for the Modified Photo-Fenton reaction because it has a relatively higher final pH and MTBE removal efficiency than the others, and it has a relatively low toxicity and is rapidly biodegradable. MTBE degradation was found to follow pseudo-first-order kinetics. Under the optimum conditions, [$Fe^{3+}$] : [Citrate] = 1 mM: 4 mM, 3% $H_2O_2$, 17.4 kWh/L UV dose, and initial pH 6.0, the 1000 ppm MTBE was degraded by 86.75% within 6 hours and 99.99% within 16 hours. The final pH value was 6.02. The degradation mechanism of MTBE by the Modified Photo-Fenton Reaction included two diverse pathways and tert-butyl formate (TBF) was identified to be the major degradation intermediate. Attributed to the high solubility, stability, and reactivity of the ferric-citrate complexes in the near neutral condition, this Modified Photo-Fenton reaction is a promising treatment process for high concentrations of MTBE under or near a neutral pH.

• Korean Journal of Weed Science
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• v.9 no.2
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• pp.116-122
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• 1989

An experiment was carried out at the International Rice Research Institute in 1987 to understand the seed dormancy and germination habit of rice and several weed species. The germinability of the weed seeds just after harvest was variable depending on the species and ranged from 0 to 72%. Two rice cultivars, IR64(lowland type) and UPLRi-5(upland type) had higher than 95% in germination ability throughout the experimental period due to the fact that the rice seeds came from the harvest of the previous season and dormancy had already been overcome. The length of the storage period needed to overcome dormancy at room temperature($25{\pm}2^{\circ}C$) was about 50 days for Echinochloa glabrescens Munro ex Hook, f., more than 60 days for E. crus-galli ssp. hispidula (Retz.) Honda and 20 days for Ludwigia octovalvis(Jacq.) Raven. Seeds of E. colona(L.) Link, Monochoria vaginalis(Burm. f.) Presl, Fimbristylis miliacea(L.) Vahl and Cyperus difformis L. appeared to have no dormancy. Among the nine species M. vaginalis had the lowest germination of less than 1% throughout the experimental period. However, its seed germinated easily when planted in soil. The low germinability of E. glabrescens, E. crus-galli ssp. hispidula and L. octovalvis just after harvest could be overcome through pretreatment of seeds either by soaking in nitric acid(0.1N) for 1 day or removal of the hull in the grass species, the nitric acid treatment being superior. The results imply that germination habit of weed species varied depending on the species through their differential dormancy period or differential germination strategy.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.21-27
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• 1996

This experiment was conducted to find out an effective propagation method for reed(Phragmites communis Trin.), ensuring a continuous herbicide screening for reed control. Reed propagation methods were compared under a greenhouse condition using tour different materials; seeds, rhizomes, depressed stolons of P. japonica Steud., and stem cuttings. Although reed seeds were easy to harvest and store, their germination rate(${\leq}$5%) was very low and seedling growth from the seeds was slow. Rhizomes were difficult to harvest and their harvest time was limited from November to March. Furthermore, reed propagation using rhizomes had problems of a relatively low germination rate(46%), no uniformity in size and shape, individual differences at the early stage of growth, and difficulties in material storage. Rate of reed growth from rhizomes was higher in commercial soil mix(Boo Nong soil) than in sand or in sand+upland soil(1:1). Depressed stolons of P. japonica had a moderate germination rate(65%) and were relatively easy to harvest. However, their harvest time was limited only from August to September. Propagation method using stem cuttings had several advantages over the above methods using other materials. Reed plants could uniformly be propagated from the stem cuttings with a relatively high germination rate(75%). Stem cuttings of central nodes showed a higher germination rate compared to those of upper or lower nodes. Stem cuttings from the field should be used immediately after harvest, since their germination rate decreased rapidly when they were stored under a wet- or a dry-refrigerated condition. Furthermore, the germination of stem cuttings tended to decrease when they were collected from the field after August. This indicates that there is a limitation of harvest time for stem cuttings. However, a year-round propagation of reed using stem cuttings is possible if parent plants are grown in a greenhouse, and thus herbicide screening for reed control could continuously be performed.