• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.210-219
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• 2003

To develop natural flavoring substances, optimal two stage enzyme hydrolysis conditions and flavor compounds of short-neck clam (Tapes philippinarum) enzyme hydrolysates were examined. The optimal enzyme hydrolysis conditions for two stage enzyme hydrolysate (TSEH) of short-neck clam were revealed in temperature at $55^{\circ}C$ for 4 hours digestion with alcalase at the 1st stage and 4 hours digestion at $45^{\circ}C$ with exopeptidase type neutrase at the 2nd stage. In quality tests of hot-water extracts, steam extracts and 4 kinds of enzyme hydrolysates, TSEH processing method was superior to other methods in yield, nitrogen contents, organoleptic taste such as umami intensity and inhibition of off-flavor formation, and transparency of extract. Total free amino acid contents in hot-water extract, steam extract and TSEH were 1,352.1 mg/100 g, 1,174.1 mg/100 g and 2,122.4 mg/100 g, respectively, Major free amino acids in TSEH were glutamic acid, glycine, alanine, tyrosine, phenylalanine and arginine. As for nucleotides and other bases, betaine, TMAO and creatinine were principal components in TSEH. The major inorganic ions in TSEH were Na, K, P and Cl. TSEH also revealed very higher angiotensin-I converting enzyme inhibition effect $(70.7\%)$ than those of hot-water and steam extract. We conclude that TSEH from short-neck clam was more flavorable compared with the seasoning materials on the market, it could be utilized as the instant soup base and the seasoning substances for fisheries processing.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.418-428
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• 2017

In this study, the effects of pre-converted nitrite from Swiss chard powder (PS) on the color stability and shelf-life of cooked pork patties during refrigerated storage for 28 d were investigated. Nitrite was added at a concentration of approximately 120 ppm. Five treatments were formulated as follows: Control (120 ppm nitrite), T1 (2% PS), T2 (2% pre-converted nitrite from celery powder; PC), T3 (1% PS + 60 ppm nitrite), and NC (nitrite-free). The T1 and T3 samples had higher nitrosoheme pigment contents, which were associated with the redness of the samples (p<0.05). T1 resulted in the highest redness value (p<0.05). The redness and yellowness of the cooked pork patties increased with increasing PS levels. The pH of the samples subjected to all treatments decreased with progress of the storage period (p<0.05). The pH of the T1 and T3 samples treated with PS was lower (p<0.05) than that obtained with other treatments, as PS has a lower pH value. The treatments in which PS was added were most effective for reducing the level of thiobarbituric acid reactive substances (TBARS) and the residual nitrite content relative to the control. T1 resulted in the highest flavor, off-flavor, and overall acceptability scores during storage (p<0.05). The total viable bacterial count for all treatments was below 1 Log CFU/g, and E. coli and coliform bacteria were not detected during storage. Therefore, these results suggested that pre-converted nitrite from Swiss chard powder is a potential replacement for nitrite in meat products.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.50-58
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• 1987

This study was conducted to examine the changes of sensory and instrumental characteristics focusing on flavor and texture of cooked rice with Akibare(Japonica type) and Milyang 23(hybrid of Japonica and Indies) under two different storage temperatures. The changes of sensory characteristics were not significant throughout the storage of 70 days at $5^{\circ}C$, but were significant after 30 days storage at $30^{\circ}C$. The stepwise regression showed that stickiness, gloosiness and off-flavor of rice effected on overall preference in old rice stored at $30^{\circ}C$. As making storage temperature be tiger and period be longer, hardness, springiness, gumminess and chewiness were increased further but cohesiveness and adhesiveness were decreased in the texture changes of cooked rice measured by Instron.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.730-736
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• 2013

This study was to establish irradiation process for serving ginseng chicken porridge to immune-compromised patients. Raw chicken, glutinous rice, ginseng, garlic, dried jujube and carrot were used as raw materials for ginseng chicken porridge. The initial level of microorganisms contaminated in raw materials and their predominant species were determined. The level of microorganism detected in raw chicken and in ginseng were 3.4 Log CFU/g and 4.7 Log CFU/g, respectively. Major predominant microorganisms were Pseudomonas fragi in chicken, Enterobactor faecalis in carrot, and Bacillus subtilis in other materials. Chicken and carrot were excluded from irradiation treatment because ordinary thermal treatment can inactivate the microorganisms contaminated in those materials. Five kGy of gamma ray was the effective sterilizing dose required to inactivate B. subtilis in glutinous rice, garlic and jujube, and 10 kGy in ginseng. Ginseng chicken porridge was prepared with each of raw materials gamma-irradiated with the selected sterilizing doses. Control was ginseng chicken porridge prepared with non-irradiated materials. The growth of microorganisms was not observed in the chicken porridge prepared with irradiated raw materials. Sensory results showed that the score of flavor and off-flavor was slightly lower in ginseng chicken porridge prepared with irradiated raw materials than in control. This was considered to be due to the increase of TBARS values by gamma irradiation. However, there was no significant difference on overall acceptance between the porridge prepared with irradiated raw materials and control. The results showed that the individual gamma irradiation of raw materials can be applied to prepare ginseng chicken porridge as meals for the immunocompromised patients.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.208-220
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• 2016

Purpose: Fusel oil is a potent volatile aroma compound found in many alcoholic beverages. At low concentrations, it makes an essential contribution to the flavor and aroma of fermented alcoholic beverages, while at high concentrations, it induced an off-flavor and is thought to cause undesirable side effects. In this work, we introduce Fourier transform near-infrared (FT-NIR) spectroscopy as a rapid and nondestructive technique for the quantitative determination of fusel oil in the Korean alcoholic beverage "soju". Methods: FT-NIR transmittance spectra in the 1000-2500 nm region were collected for 120 soju samples with fusel oil concentrations ranging from 0 to 1400 ppm. The calibration and validation data sets were designed using data from 75 and 45 samples, respectively. The net analyte signal (NAS) was used as a preprocessing method before the application of the partial least-square regression (PLSR) and principal component regression (PCR) methods for predicting fusel oil concentration. A novel variable selection method was adopted to determine the most informative spectral variables to minimize the effect of nonmodeled interferences. Finally, the efficiency of the developed technique was evaluated with two different validation sets. Results: The results revealed that the NAS-PLSR model with selected variables ($R^2_{\upsilon}=0.95$, RMSEV = 100ppm) did not outperform the NAS-PCR model (($R^2_{\upsilon}=0.97$, RMSEV = 7 8.9ppm). In addition, the NAS-PCR shows a better recovery for validation set 2 and a lower relative error for validation set 3 than the NAS-PLSR model. Conclusion: The experimental results indicate that the proposed technique could be an alternative to conventional methods for the quantitative determination of fusel oil in alcoholic beverages and has the potential for use in in-line process control.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.677-683
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• 2016

To enhance the physiological activities and reduce the off-flavor of garlic in kimchi, we manufactured kimchi seasoning replaced with 25~75% black garlic, we evaluated microbiological, physico-chemical and sensory evaluation. The changes of total aerobic and lactic acid bacteria were similar between the control and the kimchi seasoning replaced with black garlic during storage periods. The lightness of the kimchi seasoning replaced with black garlic was lower than that of the control and decrease of lightness was proportional to the concentration of black garlic. The redness and yellowness of the kimchi seasoning replaced with black garlic were decreased to the concentration of added black garlic and changes of the redness in all the samples were slightly increased during storage periods. But the yellowness did not change during storage periods. The changes of pH and acidity did not differ between the control and the samples of replaced with black garlic during storage periods. The sensory parameters including taste and flavor did not differ among treatments during storage periods. But color and overall acceptance of the control and sample replaced with 25% black garlic were higher than those of the samples replaced with 50 and 75% black garlic.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.441-448
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• 2016

Purpose: This study was conducted to investigate the effect of cabbage powder on the quality characteristics of rice nutritional bars. Methods: In order to analyze quality characteristics, total phenolic content, DPPH free radical scavenging activity, baking loss rate, leavening rate, specific volume, moisture content, color, texture analysis, and sensory evaluations were assessed. Results: The total phenolic content and DPPH free radical scavenging activity of rice nutritional bars significantly increased with an increase in the content of cabbage powder (p<0.05). The baking loss rate, leavening rate, specific volume, and moisture content of the rice nutritional bars were significantly reduced as the amount of added cabbage powder increased (p<0.05). As the concentration of cabbage powder increased, the lightness and redness of the bars' crust and crumbs decreased, while yellowness increased (p<0.05). In texture analysis, the control bars showed the highest hardness values. Adhesiveness, springiness, and cohesiveness values slightly decreased with higher cabbage powder content in the groups with added cabbage powder (p<0.05). When consumer acceptability was measured, rice nutritional bars prepared with 15% cabbage powder showed the highest scores in color, whereas the rice nutritional bars prepared with 20% cabbage powder showed the lowest scores in flavor (p<0.05). In characteristic intensity rating, the taste and off-flavor of rice nutritional bars significantly increased with increasing amounts of cabbage powder (p<0.05). Conclusion: Judging from our results, it can be concluded that the addition of cabbage powder to rice nutritional bars during processing can enhance consumer preference for the bars, total phenolic content, and DPPH free radical scavenging activity.

• Korean journal of food and cookery science
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• v.26 no.4
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• pp.406-412
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• 2010

This study was conducted to investigate the effects of saltwort on the quality characteristics of tofu. In addition, we examined the potential for commercialization of tofu containing saltwort. For this study, saltwort was added to tofu at 0%, 4%, 8%, 12%, 16% and 20% and quality and sensory tests were administered. Analyzing the mineral contents of saltwort juice, K was present in the greatest amount, followed by Mg, P, Ca, and F (in decreasing order). There were significant differences in yield rates and turbidity between the groups. Acidity was highest in the control group, and acidity and volume of tofu tended to decrease with an increase in saltwort powder. L value and a value decreased as the content of slaltwort powder increased, but b value increased with increasing saltwort powder concentration. Hardness, chewiness, and gumminess were rated higher in the control and the 4% supplement groups than the others groups. In the sensory evaluation, cross section and soybean flavor were the highest in the 4% saltwort supplement group, and the presence of an "off-flavor" increased with the content of saltwort powder. The saltiness score was highest in the 20% supplement group. The 4% and 8% supplement groups were favored in the "feel after swallowing" assessment. Softness was the lowest in the 20% supplement group, and the 4% supplement group had the highest overall acceptability. As demonstrated by these results, the addition of saltwort positively affected the overall sensory evaluation of tofu and supplementation with saltwort at 4% and 8% might be considered the most appropriate choices. In conclusion, saltwort tofu expected to increase the functionality of new products, particularly with respect to product variety and health improvement.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.982-986
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• 1997

Propolis extract was added to white bread(P1-1.48%, P2-0.74%, P3-0.37%), prepared in the straight-dough method, and its effects on shelf-life, antimicrobial activity, staling and sensory evaluation of white bread were investigated. In all P1, P2 samples, added propolis inhibited the growth of fungi, and the more propolis extract was added, the higher degree of inhibition of fungal growth was observed. The staling rates of white breads with P1, P2 and P3 were retarded by 22.5%, 19.2% and 6.4% respectively compared to that of control, and the Avrami exponent was similar in all samples. As a result of sensory evaluation, flavor, off-flavor, texture and overall acceptability of P2 and P3 were not significantly different from that of control.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.799-804
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• 2002

Optimum conditions of freeze-dried carrots were determined using response surface methodology. Physicochemical and sensory properties of freeze-dried carrot prepared at different plate temperatures and chamber pressures were evaluated. Drying time increased with decreasing plate temperature and chamber pressure. Rehydration ratio decreased inversely with chamber pressure at low plate temperature, but increased proportionally with chamber pressure at high temperature. Density, color, and sensory off-flavor were not affected by the plate temperature and chamber pressure. Sensory color, tenderness, and carrot flavor increased with decreasing plate temperature, but were not affected by chamber pressure. Based on the drying time, rehydration ratio, and sensory attributes, optimum plate temperature and chamber pressure for the preparation of freeze-dried carrot were determined as $43^{\circ}C$ and 700 micronHg, respectively.