• Food Science and Preservation
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• v.18 no.4
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• pp.488-496
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• 2011

Cold-air drying was conducted for a steamed pumpkin-sweet potato slab to improve its quality, convenience, and preference as a snack. A steamed pumpkin-sweet potato slab was dried from 10 to $25^{\circ}C$ for 48 h, and its moisture content, color, texture, and taste at different drying temperatures and drying times were evaluated. The lowest moisture content was 4.98%, at $25^{\circ}C$. The lightness decreased, but the other color values (a, b, and ${\Delta}E$) increased with the increasing drying temperature and drying time. The reducing sugar and soluble solid ranged from 98.7 to 194.75 mg/g and 19-70 $^{\circ}Brix$, respectively. The highest hardness of the steamed pumpkin-sweet potato slab was 23.88 $kg_f/cm^2$, and the springiness and cohesiveness were 91.15 and 98.36% when it was dried at $25^{\circ}C$ for 48 h. The sensory evaluation score was high at $10^{\circ}C$, 40 h and at $25^{\circ}C$, 24 h. The optimum drying condition was predicted at $19^{\circ}C$, 32 h via response surface methodology (RSM).

• Food Science and Preservation
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• v.16 no.1
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• pp.68-74
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• 2009

This study investigated the quality characteristics of breads made with addition of lotus(Nelumbo nucifera) seeds powder. Breads were prepared with 0, 5, 10, 15 and 20%(w/w) lotus seed powder instead of wheat flour. The moisture, crude protein, crude fat, crude ash and crude fiber contents of the breads increased as the proportion of lotus seed powder increased. The pH of the breads increased as lotus seed powder levels increased. The weight of breads increased with increasing lotus seed powder levels, whereas volume decreased. The specific volumes of breads with lotus seed powder were in the range of $3.59{\sim}4.68\;mL/g$, whereas the control value was 5.12 mL/g. The baking loss rates of breads prepared with 5%, 15% and 20% lotus seed powder were 8.95%, 8.17% and 7.67%, respectively. Lightness (L value) of breads was decreased by addition of lotus seed powder, whereas redness (a value) and yellowness (b value) increased in crumb and crust. Texture measurements showed that hardness and gumminess increased with increased lotus seed powder levels, but springiness decreased. In sensory evaluation, the highest scores for flavor, taste and overall preference were obtained when lotus seed powder content was 10%, and color and texture were the best when 5% of lotus seed powder was added. Thus, addition of $5{\sim}10%$ lotus seed powder may have a role in functional bread preparation, resulting in improved quality.

• Food Science and Preservation
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• v.20 no.4
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• pp.467-474
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• 2013

This study demonstrated that the physiochemical properties and anti-oxidants activities of soy sauce with Oak mushroom (MK) and Astragalus memyranaceus (AK) improved in sensory acceptability and functionality during the ripening period of 30 days. The pH content was reduced and the total acidity content was increased with time. The total sugar of AK and MK was higher than traditional soy sauce (TK), and the changes in amino nitrogen of the AK increased dramatically from 0.50 to 0.98%. During the antioxidant experiments, the total polyphenol and flavonoid contents increased at a steady rate and studies showed that the DPPH free radical scavenging activities were higher in all treatments except in the traditional soy sauce. According to the results of this study, the antioxidant activities of the AK and MK were higher than the TK, while the preference for the AK and MK was higher than the TK. In conclusion, the AK could be used as a functional soy sauce.

• Food Science and Preservation
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• v.22 no.5
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• pp.768-777
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• 2015

Persimmon contains high levels of vitamins and phenolic compounds, as well as soluble solids, necessary for the fermentation of persimmon wine. Co-fermentation of persimmon wine was carried out using a mixed culture of Pichia anomala JK04, a Korean indigenous yeast that improves wine quality and flavor, and Saccharomyces cerevisiae Fermivin, an industrial wine yeast, in the following ratios: 9:1 (v/v), 5:5 (v/v), 1:9 (v/v) and 0:10 (v/v). During fermentation, the alcohol contents increased more slowly in samples of mixed culture than in samples of the single culture of S. cerevisiae Fermivin. The alcohol contents of all samples reached 12~13% (v/v) after 15 days. All samples of the mixed culture showed greater variety in flavor and taste than S. cerevisiae Fermivin only. In the sensory evaluation, mixed culture samples had higher scores in terms of flavor and overall preference than the single culture samples. Therefore, P. anomala JK04 is thought to improve the wine flavor of Korean domestic persimmon wine.

• Food Science and Preservation
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• v.20 no.2
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• pp.265-271
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• 2013

The objective of this study was to assess the quality characteristics of yanggaeng prepared with different ratios of blueberry powder: 0%, 3%, 6%, and 9%. The moisture content of the control yanggaeng was lower than that of any other blueberry added groups. The pH decreased while the titratable acidity and the Brix increased as the amount of blueberry powder increased. The lightness (L) and yellowness (b) were the highest while the redness (a) was the lowest in the controls. Texture profile analysis showed that the hardness of the added groups were higher than that of the control which were the lowest. The total polyphenol content and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity increased as the amount of blueberry powder increased. The results of consumer acceptance test revealed that the color preference was the highest in the 9% added group while the smell, taste, texture and the overall acceptability showed no significant differences groups. Based on these results, it is suggested that yanggaeng with up to 9% added blueberry powder can be developed as products without adverse effects on sensory characteristics.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.202-208
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• 2006

Juice obtained from premature citrus fruits was deacidified by electrodialysis (ED), and its physicochemical and functional properties were evaluated. Total acidities decreased from 3.15 (Aug), 1.62 (Sep), and 1.45% (Oct) to 2.37 (Aug), 0.86 (Sep), and 0.74% (Oct) by electrodialysis for 100 min, respectively, whereas $^{\circ}Brix$ to acid ratio increased, and pH and color remained almost unchanged. Free sugar content of premature citrus juice remained almost unchanged, while organic acid content decreased significantly. Narirutin and hesperidin contents among flavonoids slightly, but not significantly, decreased. $K^+,\;PO_4\;^{2-},\;SO_42^-,\;and\;Cl^-$ contents decreased by ED, with $K^+$ content showing more than 60% decrease, while $Na^+$ content increased 2.5-3.5 times. Total polyphenol content and electron-donating ability decreased slightly by ED, while nitrite-scavenging ability remained almost constant. Sensory evaluation indicated juice (Sep) subjected to ED processing to $12^{\circ}Brix$ with sugar had the highest preference.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.64-68
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• 2009

The effects of drying methods (hot air, cold air, vacuum, and infrared drying) on physicochemical and organoleptic qualities of sliced-dried persimmons (Diospyros kaki Thumb. cv. Cheungdobansi) were investigated. The weight of the sliceddried persimmons ranged from 9.30 to 12.01 g, the length from 3.55 to 4.06 cm, the width and thickness were from 3.17 to 3.73 cm and 1.82 to 2.04 cm, respectively. Hot air drying resulted in the highest hardness value as well as Hunter's L, a, and b values. Infrared drying showed the lowest L value and vacuum drying revealed the lowest a and b values. Moisture contents of the sliced-dried persimmons ranged from 38.04 to 46.41%, and soluble solid contents were 42.96-$48.44^{\circ}Bx$. The phenolic compounds and DPPH radical scavenging activity were high for infrared and vacuum drying methods, and all the sliced-dried persimmons showed relatively high antioxidant activities. The sensory evaluation results indicated that the organoleptic scores for the overall preference were high in the order of vacuum > infrared > hot air > cold air drying. These results suggest that the drying methods affected the qualities of the sliced-dried persimmons, showing that vacuum drying is the mast effective among the methods tested for manufacturing the high-quality sliced-dried persimmons.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.446-455
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• 2014

In this study, we aimed to develop mixed grain-derived hard liquor with enhanced favor and taste. First, fermentation characteristics analysis according to the grain used showed that rice and adlay produced high alcohol outputs of 15.2% and 13.3%, respectively, while that of barley was low at 5.6%. In an experiment in which different amounts sorghum flour were added, the sample without sorghum flour showed an alcohol content of 19.0%. The effect of adding up to 7% ipkuk (koji) was examined in a sensory test. Comprehensive preference increased with increasing amounts of added ipkuk. Fermentation characteristics analyses of distilled liquor into which milled rice (5% degrees of milling of unpolished waxy rice) was added showed that alcohol content and acidity were not greatly affected by its addition. Finally, an analysis of aromatic ingredients showed that the percentage of ethyl palmitate, which produces a smooth aroma, was the highest in distilled liquor made of mixed grains.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.461-465
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• 2016

In order to prevent the blackening and texture softening of heated shrimp, the pH was adjusted by soaking shrimps in acidic and alkali solutions, and their qualities were evaluated. The lightness of shrimps pretreated with 0.2% (w/w) citric acid and 0.05% (w/w) ascorbic acid solution increased by 20% compared to that of the control. The strength of mechanical hardness of shrimps soaked in acetic acid and phosphate solution (pH 6.0) was significantly higher ($1209g_f$) compared to that of untreated shrimp ($801g_f$; p<0.05), and the overall preference of texture was 0.4 points higher than that of the control in the descriptive sensory evaluation (p<0.05). In contrast, soaking in solution of pH 8 exhibited a weak texture hardening effect ($855g_f$). Additionally, the hardness of the heated shrimp after soaking at an adjusted pH of 4.0 increased to $4046g_f$, but the yield based on weight decreased to 38% compared to that of untreated shrimp (70%; p<0.05).

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.387-395
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• 2000

The rheological properties of wheat flour dough and qualities of bread prepared with 0, 10, and 20% of dietary fiber slurry extracted and purified from ascidian (Halocynthia roretzi) tunic were investigated. Water absorption of the dough increased with the increase of dietary fiber slurry. Both arrival and development time of the dough with 10 and 20% dietary fiber slurry added were shorter than those of the control. An increase in the added amount of the dietary fiber slurry resulted in an increase of weakness. The dough's extensibility and resistance to extension were decreased, and the ratio of resistance to extensibility (R/E) decreased with the increase in the dietary fiber slurry. The maximum viscosity gradually decreased with the increase in the amount of dietary fiber slurry, while the temperature of gelatinization was not changed. Both loaf and specific volume of bread were slightly decreased with an increase in the amount of dietary fiber slurry. Overall preference scores by sensory evaluation and the quality characteristics of the bread with up to 20% dietary fiber slurry added was not significantly different from those of the control(p<0.05). The results indicated that the addition of the dietary fiber from ascidian tunic retarded staling and improved the shelf-life of the bread by enhancing the water holding capacity.