• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.215-220
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• 2008

Rahnella aquatilis AY2000 has an unique characteristic which produces an anti-yeast substance (AYS). The AYS of the strain AY2000 was always secreted on agar plate, however, its activity in liquid culture was labile upon storage of the medium. In this paper, cultural conditions of the strain AY2000 for the AYS production were investigated in liquid culture, and minimal inhibitory concentration (MIC) against Saccharomyces cerevisiae was determined for the AYS activity. MIC of the AYS cultured in PYG broth at $^25{\circ}C$ for 24 hr was $23.5{\mu}g/mL$, however, that in MYCS (pH 5.5) broth at the same condition was $15.5{\mu}g/mL$. The activity of the AYS had increased rather in MYCS broth excluded $NH_4$-citrate than in the same broth contained $NH_4$-citrate, and MIC of the AYS produced in MYCS broth without $NH_4$-citrate was $15.5{\mu}g/mL$. When the strain AY2000 was maintained in MYCS broth without $NH_4$-citrate but added $100{\mu}M$ $FeCl_3$, the activity of the AYS had increased and its MIC was $7.8{\mu}g/mL$. MIC of the AYS was $7.8{\mu}g/mL$ after the strain AY2000 was cultured in MYCS broth containing $100{\mu}M$ $FeCl_3$ without $NH_4$-citrate, however, its MIC was $31.3{\mu}g/mL$ after 48-60 hr culture in the same broth.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.568-576
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• 2012

Baksulgi with various sugar substitutes was prepared and characterized for physicochemical and sensory qualities. The 10% sugar in a control baksulgi was replaced with 16.1% glucose, 13.3% erythritol, 10.2% xylitol, 0.2% stevioside (enzymatically modified stevia 100%), 0.05% aspartame, or 1.2% sucralose. Instrumental and sensory analyses indicated that the baksulgi with glucose was significantly different in color from the others, which was attributed to high susceptibility to browning reaction of the glucose. Baksulgi with aspartame showed significantly lower pH than that of control baksulgi, suggesting that the aspartame might have been hydrolyzed into its constituent amino acids under elevated steaming temperature. A sensory evaluation revealed that baksulgi with sucralose or xylitol was comparable to the control baksulgi in all sensory characteristics. However, the baksulgi with sucralose showed appreciably increased hardness with increased storage time at $4^{\circ}C$, partially due to the anhygroscopic property of sucralose.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.589-594
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• 1997

This study was performed to clarify the effect of anesthesia killing and non-bleeding on the physicochemical and rheological properties of plaice, Paralichthys olivaceus muscle at early period after death. Live plaice was killed by the two different methods: spiking at the brain instantly with bleeding and dipping In seawater containing anesthetic (2,000 ppm ethyl-aminobenzoate) for 10 min without bleeding. These samples were stored at $0^{\circ}C$ and used in checking rigor-mortis, ATP breakdown, the content of ATP and its related compounds, breaking strength, and lactate accumulation through storage. The rigor-mortis, ATP breakdown, and lactate accumulation was faster in samples killed by spiking than in samples killed by anesthesia. ATP in samples killed by anesthetic showed little breakdown until 22.5 hrs, but it was decomposed completely after 30 hrs storage. Breaking strength of samples killed by spiking at the brain instantly with bleeding decreased steadily and showed the maximum value over 10 hrs $(2207.3{\pm}60.2g)$. However, in case of the dipping fresh flesh without bleeding in seawater containing anesthetic, the value and time reached around the maximum breaking strength were $2147.8{\pm}29.0g$ and 13 hrs respectively, but it maintained constantly until 20 hrs passed. From these results, it could be suggested that anesthesia killing and non-bleeding is more effective in maintaining firmness of fresh plaice muscle than spiking killing with bleeding at the early period after death.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.339-346
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• 2012

The quality characteristics of kochujang added with additives of different ratios of rice-nuruk (at 1:0.7, 1:1.0, 1:1.3) were studied. The kochujang was stored for 8 weeks at $20{\pm}3^{\circ}C$. The brix tended to increase by increasing mixing ratio of rice-nuruk in all treatments. It increased rapidly up to 4 weeks fermentation and then showed a slight change after 6 weeks. The more mixing ratio of rice-nuruk increased, the more salinity of samples decreased. The initial pH value of kochujang was 5.08-5.10., however, the pH value decreased to 4.82-4.83 after an 8 weeks of storage period. The initial acid value was 0.66-0.68 and increased from 0.66-0.68 to 0.87-0.89. It had slight reduction phenomenon in the sixth week. As the aging period passed, chromaticity such as $a^*$- and $b^*$-values decreased gradually except for $L^*$-value. The moisture content of samples decreased gradually by adding rice-nuruk. but increased by passing an aging period. The initial amino nitrogen content of sample was 304-315 mg%. It increased to 399-442 mg% during the aging period. As the aging period passed, the total cell number increased from 6.81 log CFU/mL to 7.01 log CFU/mL in the fourth week and then steadily decreased to 6.66 log CFU/mL in the eight week. Results of sensory evaluation show that, as more rice-nuruk was added, the kochujang received a lower mark. There was no significant difference in flavor in all treatments. Color and sweetness with increasing amounts of rice-nuruk showed the lowest score. Saltiness rice-nuruk at the ratio of 1:1.0 was the highest at 6.22 points. Texture scores decreased with increasing amounts of the rice-nuruk Based on these results, the overall acceptability of the 1:0.7 rice-nuruk treatment which received the highest score is considered excellent.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.592-601
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• 1997

The purposes of this study were to develop Hazard Analysis Critical Control Point-based standardized recipe applicable to cook/chilled soy sauceglazed mackerel and to evaluate the qualities related to the product flow of this item. After conducting experimental cooking, preliminary test, and analysis of recipes, critical control points were identified, control methods were determined, and HACCP-based recipe was standardized. At each critical control point, time-temperature profile was recorded and microbiological analysis (total aerobic plate counts, psychrotrophic plate count, coliform, and fecal coliform count), chemical analysis (pH, acid value and volatile based nitrogen (VBN)) and sensory evaluation of the item were done. Time-temperature data showed that the time the menu item had passed through temperature danger zone (5∼60$^{\circ}C$) during all phases was 60 min. At rapid cooling, but after cooling at room temperature, the temperature of this menu item did not drop below the ambient temperature. The results of microbiological test were negative throughout all phases following cooking and the results of chemical analysis did not change significantly in terms of storage periods except for VBN which increased on 7th day significantly(p<0.05). After steam/convection oven reheating and microwave oven reheating, the sensory score of the only appearance decreased significantly related to the storage time of overall quality profiles. But significant differences were not detected according to two reheating methods. In conclusion, this HACCP-based recipe was considered as an effective tool for assuring microbial as well as sensory quality of this cook/chilled item.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.635-640
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• 1997

The oxidative stability of the potato chip prepared with canola oil fortified with antioxidnats was studied to explore the possibility of substituting it for imported frying fats and oils. BHT, BHA, TBHQ and silicone were added to the oil at a level of 0.02% and 10 ppm, respectively. Potato chip samples were prepared in a commercial scale and stored at $25.0{\pm}0.5^{\circ}C$ for 5 months. The oxidative stability of the extracted oils from potato chips during storage was estimated on the basis of some their physico-chemical changes, such as acid values, peroxide values, iodine values, ansidine values, fatty acid composition of the oils. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samlpes was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of canola oil+TBHQ (0.02%)+silicone (10 ppm) > canola oil+TBHQ (0.02%) > canola oil+BHA (0.02%)+silicone (10 ppm) > canola oil+BHT (0.02%)+silicone (10 ppm) > canola oil+BHA (0.02%) > canola oil+BHT (0.02%) > canola oil. The antioxidant effect of canola oil+TBHQ (0.02%)+silicone (10 ppm) was more salient than any other antioxidant used in the potato chip.

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.589-597
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• 2011

This study was performed to evaluate the physiological and sensory properties of breads with different ratios of persimmon peel. Moisture activation of the bread loaf decreased as storage period increased with a smaller range of decrease in the persimmon peel added group. The amount of weight increased, and volume fell to some degree. Adding persimmon peel increased the RVA temperature, whereas maximum decreased. The color change during storage was due to the addition of control and 4% in group a values except there was no significant difference. As the result of measurements using a texture analyzer, hardness, springiness, cohesiveness, gumminess, and chewiness properties decreased. The sensory test results revealed that the 4% and 6% added persimmon peel bread was the best.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.450-458
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• 2017

In this study, the antimicrobial activity of black garlic pomace extract (BGPE) was examined, and its washing applicability to spinach was investigated. BGPE had antimicrobial activity against both Gram-positive (Listeria monocytogenes and Staphylococcus aureus) and Gram-negative (Escherichia coli O157:H7 and Salmonella Typhimurium) food-borne pathogens. In particular, antimicrobial activities of BGPE against Gram-positive bacteria were higher than those against Gram-negative bacteria. Spinach samples were treated with 0.5% BGPE to determine the effect of BGPE on reducing naturally existing microorganisms on the surface of spinach leaves. BGPE treatment reduced populations of total aerobic bacteria and yeast/molds in spinach by 1.23~1.35 log CFU/g and 0.82~1.12 log CFU/g during 9 days of storage, respectively, compared with those of control samples. After treatment, there were no significant differences in color quality such as Hunter L, a, and b values and total color difference (${\Delta}E$). These results clearly indicate that BGPE treatment can be useful for improving microbiological safety and maintaining color quality of spinach during storage.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.117-121
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• 1992

The changes in sensory and mechanical texture of chewing gum during storage at various relative humidity were studied to define the quality index for the prediction of shelf-life. The initial moisture content of chewing gum was 2.57% (dry basis). The BET monolayer value at $a_{w}$ 0.19 was calculated to be 1.57% (dry basis). The sensory scores of chewing gum were closely correlated with moisture content and instrumental texture parameters with 0.1% significant level. Therefore the quality of stored chewing gum was directly related with moisture content above BET monolayer. The products became organoleptically acceptable in the range of moisture content $2.17{\sim}3.16%(dry basis)$. This range of moisture content ie equivalent to the ranges of instrumental parameter, fracture force$0.8{\sim}1.8{\times}10^{7}$, fracture modulus $1.1{\sim}2.4{\times}10^{8}$, puncture force $0.5{\sim}1.1{\times}10^{7}[dyne/cm^{2}]$ and brittleness $0.7{\sim}1.4{\times}10^{8}[dyne/cm^{3}]$, respectively.

• Restorative Dentistry and Endodontics
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• v.25 no.2
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• pp.262-271
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• 2000

The purpose of this study was to estimate shear bond strength according to difference in Targis surface treatment and storage condition. 140 non-carious extracted human molars and Targis D210(Ivoclar, Liechtenstein) were used in the present study and were divided into 7 experimental groups respectively according to surface treatment of Targis. Group 1 ; No treatment, Group 2 ; $50{\mu}m$ aluminium oxide blasting, Group 3 ; 4% HF etching for 3 minutes, Group 4 ; 4% HF etching after blasting, Group 5 ; silane treatment after blasting, Group 6 ; silane treatment after 4% HF etching, Group 7 ; silane treatment after blasting and 4% HF etching. In Each group, one half of 20 specimens was stored in distilled water at $37^{\circ}C$ for 24 hours and the other half was stored at atmosphere for 24 hours respectively. Dentin surface was etched with 10% $H_3PO_4$ for 15 seconds and luting cement(Variolink II, Vivadent, Liechtenstein) was applied by manufacturer's recommendation. Shear bond strength for each group was then measured. To examine the failure patterns after shear bond test and to observe the change after surface treatment of Targis. Specimens were fabricated and observed under the SEM. Statistical analysis was performed by One Way ANOVA test and t-test. The results were as follows ; 1. The shear bond strength of the groups stored in water significantly lower than that of groups stored at atmosphere (P<0.05). 2. There was no significant difference in shear bond strength in groups stored in water (P>0.05). 3. The shear bond strength without surface treatment of Targis were lowest among all experimental groups in atmosphere condition(P<0.05). 4. There was no significant difference in bond strength between groups using the silane or not(P>0.05). 5. The groups treated by blasting, hydrofluoric acid and silane sequentially showed highest bond strength than that of other groups in atmosphere condition, but there was no significant difference(P>0.05). 6 The proportions of the specimens showing the mixed fracture failure were 20% in HF etching group and blasting + HF group, 40% in blasting + HF + silane group in atmosphere condition. All the specimens stored in water showed adhesive fracture failure.