• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.282-291
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• 2006

Effects of the molecular weight and type of chitosans on shelf-life of Makkulli were evaluated during 18 days of storage at $25^{\circ}C$. Two types of chitosans were studied: ${\alpha}$-chitosans with 11 different molecular weights (water-soluble, Mw = 1, 8, 22, 43, 67 and 616 kDa; acid-soluble, Mw = 282, 440, 746, 1,110 and 2,025 kDa) and ${\beta}$-chitosan (acid-soluble, Mw = 577 kDa). Acid-soluble chitosans were applied as a form of chitosan-ascorbate. All chitosans were added to Makkulli at 0.002% concentration, the optimum concentration established in a preliminary test. Among 12 chitosans, the ${\alpha}$-chitosans with 22 and 440 kDa exhibited stronger antimicrobial effects than did other ${\alpha}$- and ${\beta}$-chitosans. The results for pH, acidity, alcohol concentration, viable cell counts, and sensory evaluation suggested that addition of ${\alpha}$-chitosans with 22 and 440 kDa increased the shelf-life of Makkulli by almost 1 week at $25^{\circ}C$ compared with that of control (without chitosan) and other chitosan-added groups. Extension of Makkulli shelf-life by 1 week is fairly significant in view of the magnitude of the total amount of Makkulli produced in Korea.

• Journal of Aquaculture
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• v.20 no.1
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• pp.51-55
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• 2007

This study was conducted to evaluate the muscle quality of the olive flounder fed on extruded pellet (EP) diets compared with a raw fish moist pellet (MP) diet for olive flounder, Paralichthys olivaceus in a commercial scale for a year. The sensory and physical qualities and palatable compounds were compared for evaluation of muscle quality in fish. Four diets were formulated for this experiment: two experimental EP diets (EP 1 and 2), one commercial EP diet (CEP) and MP diet. Crude lipid of fish fed EP1 and EP2 was significantly higher (P<0.05) than that of fish fed CEP, but not significantly different from that of fish fed MP (P>0.05). In the palatable compounds, the free amino acids composition were much alike in that of all the diets. Proline, glycine and alanine from fish fed diet EPs were the most abundant compound among amino acid compositions. There was little difference in the free amino acid compositions of all flounder from localities and the growing conditions between wild and cultured fishes. Taurine of fish fed EP1 was dominantly high over that of fish fed EP2, CEP and MP. In all nucleotides and their related compounds, ATP and IMP from fish fed EP diets were higher (P<0.05) than those of fish fed MP. In the sensory score, overall-acceptability of fish fed EP2 were significantly higher (P<0.05) than that of fish fed EP1, CEP and MP. Hardness of physical properties from fish fed EP2 was significantly higher (P<0.05) than those of fish fed CEP (P<0.01). These results strongly suggest that diets EP could be developed to replace MP diet for the grow-out stage of olive flounder without adverse effect on growth performance.

• Food Science and Preservation
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• v.22 no.3
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• pp.303-313
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• 2015

This study investigates the physicochemical, microbiological and sensory characteristics of seasonal salted-Kimchi cabbages to provide basic data on its uniform quality. Generally, seasonal salted-Kimchi samples had different pH values at initial storage periods, but there was no difference in pH between the seasonal samples when stored for longer periods. The samples from the fall and winter seasons were relatively low in acid and high in solid soluble content compared to samples from other seasons. Salted-Kimchi cabbages in the summer showed the highest microbiological number compared to samples from other seasons. In the sensory evaluation, there were differences in the appearance, aroma, and taste, depending on seasonal samples at different storage periods. The correlation coefficient between the quality characteristics in the seasonal samples showed a positive or negative correlation between the quality characteristics at 1% significant level. In the principal component analysis, F1 and F2 were shown the 51.81% and 14.23% of the total variance (66.21%), respectively. In the PCA pattern of seasonal salted-Kimchi cabbages during storage periods, winter samples were distributed on the top of F2, spring samples were in the middle of F2, while the rest of the samples were distributed on the bottom of F2. According to increasing storage periods, initial storage samples were distributed at the left of F1, while other samples were located at the right of F2.

• Food Science and Preservation
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• v.21 no.1
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• pp.140-145
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• 2014

The physicochemical quality characteristics of the domestic and imported commercial dried persimmons were investigated. The moisture content of dried persimmon was approximately 22.78~61.64%, while the moisture contents of the Chinese dried persimmon were 22.78 and 28.20%, respectively, and were lower than the domestic dried persimmon. The pH of the Chinese dried persimmon was 5.09~5.99, while the pH of the Haman dried persimmon has the highest value (pH 5.99). The Brix was approximately $25.07{\sim}42.93^{\circ}Brix$ and weight of dried persimmons were 29.77~77.95 g, while the weight of Yeongdong dried persimmon has the lowest (29.77 g), and the weight of the Sancheong dried persimmon has the highest value. The L values were 18.27~66.20. The a values were -1.26~10.70 and a value of the Sancheong dried persimmon was 10.70, which was the highest. The b values were 2.81~25.25, wherein the b value of the Cheongdo semi-dried persimmon and Sancheong dried persimmon were25.25 and 21.98, respectively, and were higher than others. The appearance score of the sensory characteristics were the highest in Cheongdo semi-dried persimmon, while the appearance score of Wanju black persimmon was 1.39, which was the lowest. The overall acceptability of the Chinese dred persimmons (No.2) was the highest, while that of the Yeongdong, Hadong and Sangju dried persimmons have higher values than the other dried persimmons. The sulfur dioxide content of the 9 kinds of commercial dried persimmon was lower than 10 mg/kg, but not detected.

• Journal of Life Science
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• v.20 no.3
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• pp.424-429
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• 2010

Prunus mume is rich in organic acid, and excels in antioxidant activity. However, development of processed foods using Prunus mume is very limited, and characteristics of its products are different according to the region they are processed in. In this study, we collected 13 kinds of sugar-preserved Prunus mume home-made products in Hadong, and investigated their physical and manufacturing characteristics to select a superior product. 5 kinds of sugar-preserved Prunus mume products were selected according to results of sensory evaluation, and the overall acceptability of product No.13 was superior. Moisture contents of the 5 samples ranged from 45.2~53.3%, and pH and acidity showed similar values at about 2.8 and 0.4%, respectively. Sugar content of product No.13 were slightly lower than other products. Crude protein and lipid contents were similar at about 0.4 and 0.5%, respectively. Hardness value of product No.13, selected by its texture in sensory evaluation, was higher than others. The main components of organic acids were oxalic, malic, citric and fumaric acid, and citric acid content occupied more than 60% of total organic acid content. Also, the main components of free sugar were glucose and fructose.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.135-142
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• 2000

The purpose of this study was to investigate the effects of onion and garlic juice on the lipid oxidation of fish oil as antioxidants and quality characteristics of fish muscle. The samples were treated with onion and garlic juice at 5%(w/w) or 10%(w/w) of fish muscle, and stored at 4$\pm$1$\^{C}$ and -18$\pm$2$\^{C}$ for 7 and 42 days, respectively. The results of this study were as follows: Lipid oxidation in samples was measured by AV, POV and TBA value. AV and TBA values of the samples treated with 5% onion and garlic juice were lower than those treated with l0% onion and garlic juice. POV of the samples treated with onion were lower than those treated with garlic juice. Lightness and yellowness of the sample were the highest in 10% onion and garlic juice-treated ones. The score of overall quality in sensory evaluation was the highest in the samples treated with onion juice stored at 4$\pm$1$\^{C}$.

• Food Science and Preservation
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• v.10 no.4
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• pp.476-481
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• 2003

As its high functional properties to be used as medicine or food, the cultivation of Agaricus mushroom has been expanded and iぉ commercialization required better storage methods that can extend its functional and nutritional value for longer period. We selected drying as the most plausible method to meet such requirement, and several drying conditions were investigated to locate the optimum drying condition that can be used to keep the quality of mushroom. Drying temperature of 50$^{\circ}C$, 60$^{\circ}C$, 100$^{\circ}C$ were selected to trace the drying time required to achieve the moisture content of mushrooms less than 10%. The drying temperature at 50$^{\circ}C$ required 29 hrs of drying time, while 100$^{\circ}C$ required only 10 hrs of drying tune. However, their quality characteristics on the following categories, on the degree of browning and color were investigated to find the optimum drying condition. In addition, sensory evaluation was conducted to evaluate the quality of dried mushrooms produced by each drying condition. The browning of the mushroom was evidently increased as the higher drying temperature was used and 50$^{\circ}C$ drying produced the most desirable quality of all in pileus or stipe. The aeon of browning intensified by drying temperature was comparable to the result of whiteness index value, which resulted lower L values as drying temperature increased. and the 50$^{\circ}C$ drying resulted the most highest L values among all drying samples. As the browning and whiteness results implied, the sensory evaluation result gathered from the present research indicated that the 50$^{\circ}C$ drying was the most favorable drying condition by scoring the most highest average scores on flavors, color, appearance, and overall acceptability conducted by the 10 evaluation panels.

• Food Science and Preservation
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• v.16 no.5
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• pp.650-655
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• 2009

This study was conducted to measure the quality characteristics of rough rice during low temperature drying by using an experimental dryer and heat pump with a capacity of 150kg at four temperature levels of 20, 30, 40, and $50^{\circ}C$. The quality and proper drying temperature of rough rice was investigated by measuring variations in moisture content, crack rates, germination rates and cooked rice. Temperatures over $40^{\circ}C$ is considered a high-temperature area, and below $40^{\circ}C$ is considered a low-temperature area. The drying rates were 0.3, 0.6, 0.9, and 1.3%/hr, and the crack ratios were 0, 1.6, 6.8, and 24.2% at the drying temperatures of 20, 30, 40, and $50^{\circ}C$, respectively, which showed that the higher the drying temperature was, the higher the drying rate and crack rate was. Therefore, 20 and $30^{\circ}C$ were found to be appropriate drying temperatures for avoiding crack formation, and $50^{\circ}C$ was inappropriate. At $40^{\circ}C$, the operation methods needed to be modified to limit cracking, such as increasing the tempering time. Also, as the drying temperature increased, the germination rate decreased. Germination rates at 20 and $30^{\circ}C$ were suitable for using the rough rice as a seed, and those at 40 and $50^{\circ}C$ were over 80%, which is the minimum allowable percentage. In the sensory evaluation of cooked rice, the quality of appearance, taste, and texture varied as a function of drying temperature. When considering these factors, the cooked rice that was dried at 20 and $30^{\circ}C$ was better than the cooked rice dried at high-temperature. Consequently, in view of drying temperature and rates, the best conditions for drying rough rice were below $30^{\circ}C$ and below 0.6%/hr.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1523-1528
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• 1999

The consumer's demands for minimally processed fruits and vegetables have been increased rapidly because of its convenient handling, fresh-like quality as well as producing less wastes from the environmental point of view. Asian pears which are one of the main fruits widely produced and consumed in Korea easily lost their characteristics due to browning and softening after cutting. The objective of this study is to investigate the effects of various treatments on delaying deterioration of sliced Asian pears. 'Shingo' pear slices were treated with various solutions $(1%\;NaCl,\;0.2%\;L-cysteine,\;1%\;CaCl_2\;or\;1%\;calcium\;lactate)$ and were packaged with low density polyethylene $(LDPE,\;60\;{\mu}m)$, ceramic $(CE,\;60\;{\mu}m)$ or vacuum $(Ny/PE,\;80\;{\mu}m)$ film at $20^{\circ}C\;and\;0^{\circ}C$. In order to evaluate the quality of packaged sliced pears, quality index was determined in terms of color, firmness, soluble solids, titratable acidity. ascorbic acid, changes of gas composition, microbial test, and sensory quality. The results showed that sliced 'Shingo' pears packaged with CE and vacuum film maintained better quality than with LDPE at $0^{\circ}C\;and\;20^{\circ}C$. To retard browning and softening. 0.2% L-cysteine and 1% NaCl solutions applied for 1 minute were effective to reduce surface browning of sliced pears, and 1% $CaCl_2$ was the most effective to prevent softening.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1439-1445
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• 2013

The aim of this study was to investigate the quality characteristics of rice cookies specifically prepared with rice flour following enzyme treatment. In this study, three types of specific enzyme treatments, that is, ${\alpha}$-amylase, ${\beta}$-amylase, and cellulose+${\beta}$-glucanase were applied on the effect of rice flour with respect to desired quality characteristics of the rice cookies. Based on our study results, we have found that the density of dough in the rice cookies was not significantly different between that of the non-enzyme treated (control) and the enzyme treated group. However, we found that the spread factor of rice cookies, prepared with rice flour treated with ${\beta}$-amylase, was higher than that of the control. It was also found that the moisture content of rice cookies (with added enzyme-treated rice flour) was 3.20 to 3.90%; however, this range is much lower than that observed in the control. Further, we observed that Hunter color's L-values were significantly higher for the control than those of the enzyme-treated cookies. We also found that hardness of enzyme-treated cookies was comparatively better than that of the control. In addition, the sensory acceptability scores of the enzyme-treated cookies were found to be significantly higher than the control in decisive parameters such as aroma, appearance, flavor, taste, texture, and overall acceptability. Based on our findings, we suggest that ${\alpha}$-amylase treated rice flour is an effective ingredient for improving the overall quality of rice cookies.