• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.1-3
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• 1989

We have treated polymer surfaces such as polyethylene, polystyrene and polyester by various physicochemical and biological surface modification methods to be suitable for cell adhesion. The physicochemical methods we used were $O_2$ plasma discharge, corona discharge, sulfuric acid and chloric acid treatments. For the biological treatments, blood proteins such as plasma protein, serum protein and fibronectin were adsorbed onto the polymer surfaces. Chinese Hamster Ovary (CHO) cells were cultured on the surface-modified polymers and the cell-compatibility of those surfaces were compared. The chloric acid and fibronectin treatments were found to be the best methods of rendering the polymer surfaces adhesive for CHO cells.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.683-688
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• 2015

Nowadays, sustainable and environment-friendly agriculture has become an important issue all around the world, and repeated applications of mineral and/or organic fertilizer will probably affect mineral nutrient dynamics in soil in the long term but only a limited number of observations are available. This study was carried out to investigate whether there is any influence of different fertilizer management for red pepper (Capsicum annuum L.) cultivation on soil physicochemical properties, leaf mineral content, yield and fruit quality in the aspect of long-term practice in open field condition. NPK, NPK+compost, compost only, and unfertilized control plot were included in the treatments. The application of chemical fertilizer and/or compost repeated annually for 17 years from 1994 to 2011. Soil organic matter content was higher in compost treatments than in no-manure treatments. Available phosphate and the yield of red pepper were highest in NPK+compost treatment followed by NPK (chemical fertilizer), compost, and control. The results indicate that in the long term, nitrogen supply is still needed for increasing red pepper yield, but reduction in the use of chemical fertilizer could be also possible with the proper application of compost.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.676-680
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• 2005

This study investigated the effect of thawing rate on the physicochemical properties of frozen ostrich meat. Five different thawing rates (0.33, 0.54, 0.61, 0.68, and 0.78 cm/h) were delivered by controlling the air velocity as heat convection at $15^{\circ}C$. The pH value decreased with increasing thawing rate (p<0.05). In color measurement, $L^*$-values of all treatments were lower and $b^*$-values higher than those of control, but $a^*$-values were not significantly different among the treatments except at the thawing rate of 0.33 cm/h. Increasing thawing rate tended to improve the water holding capacity (WHC) of the samples. Thawing loss decreased with increasing thawing rate and significantly higher cooking loss was observed at the thawing rate of 0.33 cm/h. Thiobarbituric acid reactive substance (TBARS) levels of all treatments were significantly higher than that of control (p<0.05). Increasing thawing rate tended to decrease the total volatile basic nitrogen (TVBN) value. These results indicated that a rapid thawing process at $15^{\circ}C$ improved the quality of frozen ostrich meat.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.832-839
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• 2006

Kugija was added to Nabak kimchi to improve the quality and preservation and the optimum addition level was assessed. Kugija extract was prepared by boiling kugija fruits, at different ratios (0, 1, 3, 5, 7%; w/v) in water for 30 minutes. The changes in the physicochemical properties of the Nabak kimchi were measured during storage for 25 days at 10?, and compared to a control (without kugija). The pH was decreased in all treatments. Following the fermentation of Nabak kimchi, the total acidity values were inversely proportional the pH changes according to the nature of mutual dependence. However, in short term, during the initial 7 days of fermentation, the total acidity values decreased with increasing concentrations of kugija extract, whereas the trend was reversed after day 10. Total vitamin C content was directly proportional to the concentration of kugija extract and was decreased with the laps of fermentation. Up to day 25, 7% treatment showed the highest vitamin C content, but at 25 days 1% and 3% treatments ranked the first. The mont of reducing sugar was proportional to the concentration of kugija extract however, the difference of values between all treatments became almost indiscernible after day 25. Turbidity values were generally increased in all samples during fermentation period, although only to a limited extent. The lowest turbidity was shown at 3% treatment up to day 16. Total color difference values were increased up to day 16, but then decreased. The optimum level of kugija extract in Nabak kimchi, as determined through these experiments, was between 1 to 3% per added water content, and was preferably 3% for color and fermentation-retarding effect of the product. Kugija extract could be applied for improving the quality and preservation of traditionally prepared Nabak kimchi.

• Animal Bioscience
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• v.37 no.5
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• pp.908-917
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• 2024

Objective: Although pork loins is not a tough meat, they need to develop meat products with a soft texture for the elderly. This study focused on the physicochemical properties and tenderness characteristics of pork loin injected with green kiwifruit juice (GRJ) and gold kiwifruit juice (GOJ) during various incubation times. In addition, the antioxidant activities of hydrolysate derived from the hydrolysis of pork loin by kiwifruit juice protease were evaluated. Methods: The pork loin was injected with 10% and 20% GRJ and GOJ, under various incubation times (0, 4, 8, and 24 h). Then, the physicochemical properties and tenderness of pork loins were measured. 2,2- diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power were conducted to determine hydrolysate's antioxidant activities derived from pork loin's hydrolysis by kiwifruit juice protease. Results: GRJ had greater tenderizing ability than GOJ, even at the 10% addition. When kiwifruit juice was injected into pork loin, the tenderness increased with increasing incubation time. This was confirmed by the decrease in intensity of the myosin heavy chain (MHC) band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In particular, the MHC band decreased at 8 h for both 10% GRJ and 20% GOJ and at 4 h for 20% GRJ alone. The highest myofibril fragmentation index and peptide solubility were observed in pork loin treated with 20% GRJ compared to the other treatments during incubation. The 10% GRJ and 20% GOJ treatments showed similar levels of antioxidant activity of the protein hydrolysates in pork loin, and 20% GRJ showed the highest activity among the treatments. Conclusion: Kiwifruit juice had protease activity, and GRJ was more useful for tenderizing meat products than GOJ. Thus, GRJ at 10% could be a potential agent to tenderize and enrich the natural antioxidant activity through the proteolysis of pork loin.

• Food Science of Animal Resources
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• v.42 no.4
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• pp.639-654
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• 2022

The current study investigated the effects of the most suitable modified atmosphere packaging (MAP) on the physicochemical, microbiological, and sensory properties of fermented dry sausages during 45 days of refrigeration (4℃) storage period. Treatments were vacuum-packed (control), 25% CO₂/75% N₂ (MAP1), 50% CO₂/50% N₂ (MAP2), 70% CO₂/30% N₂ (MAP3), and 100% CO₂ (MAP4). All MAP samples regardless of their CO₂ composition significantly (p<0.05) decreased in pH, a_w, total plate count, and lactic acid bacteria count values as compared to the vacuum-package during storage. The Enterobacteriaceae count in all MAP packaging was significantly (p<0.05) lower than the vacuum-packed samples and counts in MAP3 and MAP4 samples were markedly (p<0.05) lower than all other treatments in prolonged storage of 15 and 45 days. Based on the thiobarbituric acid reactive substance content at day 15 and 30 storage time, treatments are ranked as follows: Vacuum-packed>MAP1>MAP2>MAP3>MAP4. The a^* of MAP4 was higher than all other treatments. In the final storage days, no variation was exhibited (p>0.05) among treatments in lactic acid aroma and sourness, and MAP2 samples had the lowest (p<0.05) overall acceptability. The use of MAPs with an increase in the CO₂ from MAP1 to MAP4 samples can help in better microbial inhibition than vacuum package, and 70% CO₂/30% N₂ (MAP3) and 100% CO₂ (MAP4) were effective to maintain several quality parameters (a_w, pH, microbial inhibition, stability against lipid oxidation, and instrumental color traits) and extend the shelf life of dry fermented sausage.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.499-509
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• 2008

The purpose of this study was to investigate the changes in physicochemical and sensory properties of raw fruits during washing and chlorine treatments. Strawberry and banana were pre-prepared at different concentration of chlorinated water(0 ppm, 50 ppm and 100 ppm), immersion time(3 min and 5 min), and number of post-rinsing(1 time, 2 times and 3 times). The physicochemical properties such as pH, sugar contents, residual chlorine contents, color values and hardness of the fruits were analyzed, and the sensory quality were evaluated throughout the sterilization treatment process. After washing strawberry with 100 ppm chlorinated water and 3 times of post-rinsing, pH and residual chlorine contents were showed a little difference, while sugar contents, hardness, and color values(L, a and b) were reduced. In case of banana, pH, sugar contents and residual chlorine contents were not affected, and hardness and L color value were reduced. However, a and b color values of banana were gradually increased as the development of brown discoloration. Sensory properties of the samples were affected by the chlorine sterilization treatment. In overall acceptance, strawberry and banana treated with 100 ppm chlorinated water showed the lowest scores among treatments. Therefore it could be suggested that the application of 50 ppm chlorinated water for $3{\sim}5$ minutes with over 3 times of post-rinsing was the effective pre-preparation method without affecting the quality of the fruits.

• Food Science and Preservation
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• v.4 no.2
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• pp.155-162
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• 1997

This work was designed to determine the effect of steaming-Pretreatment on Physicochemical and functional properties of roasted Polygonatum odoratum roots. Steaming treatments led to some reduction in the contents of water solubles, such as total solid, reducing sugar and free-amino nitrogen of the unroasted samples. Moreover, roasting processing caused decrease in reducing sugar and free-amino acid, with increase in total soluble solid and browning color of the samples, which showed the dependence of steaming treatment as well as roasting temperature. Electron-donating ability and nitrite-scavenging ratio of the samples were also highly developed along with roasting processing at 17$0^{\circ}C$ within 35min. Considering the physicochemical and some functional parameters of water extracts of roasted samples, roasting at above 14$0^{\circ}C$ for over 55min or at 17$0^{\circ}C$ for around 35min was recommendable for the higher quality of Polygonatum odoritum tea, which conditions were similarly adapted for both steamed and unsteamed samples.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.628-634
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• 2015

The ground red pepper puree was treated with cellulase (C treatment), pectinase (P treatment), amylase (A treatment) and/or enzyme complex (CP, CA, PA and CPA treatment) for 2~8 hours to improve the yield and bioactivity of extracts. And physicochemical and sensory properties of red pepper extracts were evaluated. The extraction yield of the control was 38.84%, which was lower than those of the enzyme treatments. And extraction yields of enzyme complex treatments were higher than that of single enzyme treatments. Especially, extraction yield was increased to 74.37% by cellulase + pectinase + amylase complex treatment (CPA treatment). The soluble solid and reducing sugar contents were higher in the extracts treated with enzymes compared with the control. CA and CPA treatment showed the highest soluble solid and reducing sugar contents. No significant changes in lightness, redness and yellowness of the control and the samples by enzyme treatments were observed during 2~8 hours experiments. The sensory evaluation results revealed that panelists preferred the extracts with enzyme treatments to the control. Therefore, enzyme treatment for red pepper extracts is a good method to improve the yield and sensory properties.

• Food Science and Preservation
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• v.9 no.4
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• pp.362-368
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• 2002

Physicochemical properties of garlic bulb during storage with different cutting treatments were estimated. Garlic harvested in early June was used in this experiments. Various physicochemical factors of garlic bulb such as weight loss rate, rotten rate, sprouting rate, moisture content, reducing sugar content and total pyruvate content were investigated. Bulbs with roots, bulb without roots and bulb with stem length of l cm, 3 cm, 5 cm were stored at 2$\^{C}$ for eight months. The weight loss increased sharply after 8 months for all treatments. Weight loss occurred most severely in treated garlics with bulbs with 5 cm stem length and progressed steadily at low rates in bulbs with 1 cm stem length. Also, less decay and internal sprouting were observed in bulbs with 1 cm stem length. Cutting treatments of roots were not significant for internal sprouting. Incidence of other chemical properties of bulbs, contents of total sugar, reducing sugar and pyruvic acid were not significant statistically. Moisture contents of treated garlics was remarkably reduced in longer leaving stems. As a result, top-clipped leaving stems fur long, seemed to have a beneficial effect on physicochemical properties of garlic stored at 2$\^{C}$ for 8 months possibly due to reduced weight loss, rotten decaying and sprouting rates. Utilization of such results in the processing industry can be effective.