• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.329-333
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• 2011

Quality characteristics of tofu as affected by addition time (before or after coagulant) and the amount (0, 3, 6, and 9%) of astringent persimmon fruit (Diospyros kaki T. cv. Cheongdobansi) powder added were investigated. Yield and sensory acceptability were higher in tofu prepared by adding persimmon before than after adding the coagulant. The yield of tofu with added persimmon was higher than that of the control. The L value of the tofu decreased as the amount of added persimmon increased. Hardness, chewiness, and crispness of tofu made with 6% persimmon were higher than those of the others. DPPH radical scavenging activity tended to increase as persimmon concentration increased but no significant difference was observed between the 3% and 6% added persimmon treatments. A sensory evaluation showed no significant differences in aroma, beany, astringency, and texture. However, the 9% sample had the significantly lowest score for overall acceptability. Thus, astringent persimmon powder (3-6%, before coagulant addition) can be utilized as an additive during tofu processing.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.350-355
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• 2003

Raw skim milk and colloidal calcium phosphate-free skim milk were treated with microbial transglutaminase (TGase), ultracentrifuged at varying rates and were observed to contain textural properties using a scanning electron microscope (SEM). Skim milk showed irregular signs of conformation at lower centrifugal rate, and associated regular (10,000 ${\times}$g) and thin with broad holes (20,000 ${\times}$g). The associated texture became thick and irregular (40,000 ${\times}$g), and fine particles were regularly associated (100,000 ${\times}$g). When skim milk was incubated for 1 hr with TGase, casein micelles aggregated and broadened as centrifugation rate increased. When skim milk was incubated for 8 hrs with TGase, casein micelles associated to large widened aggregates, and were associated regularly which then became irregular (100,000 ${\times}$g). When colloidal calcium phosphate-free skim milk incubated for 1 hr with TGase showed no sediment, the milk incubated for 8 hrs with TGase associated together, yielding broadened and regular layers as the centrifugation rate increased. It is assumed that such phenomena could be caused by protein crosslinking reaction with TGase and conformational change of casein molecules, as well as dependencies on reaction time, temperature and ultracentrifugation rate.

• Journal of Life Science
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• v.14 no.2
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• pp.239-244
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• 2004

This study was carried out to clarify the effect of addition of mugwort and carcass grade on the quality and sensory properties of loin hams. The volatile basic nitrogen, 2-thiobarbituric acid reactive substances, total bacterial count, water holding capacity and calorie of loin hams were not significantly different among hams, but the pH and residual nitrite of loin hams with mugwort were significantly lower than that of loin hams without mugwort. The fat content of grade B loin hams were higher than that of grade E loin hams, and the protein and total amino acid content of grade E loin hams were higher than that of grade B loin hams. The free amino acid, saturated fatty acid and unsaturated fatty acid were not significantly different among loin hams. The $L^{＊}$ value of grade B loin hams were higher than that of grade E loin hams, the a value of grade E loin hams were higher than that of grade B loin hams, and the $b^{＊}$ value was not significantly different among loin hams. The hardness, springiness, cohesiveness, gumminess and chewiness were not significantly different among loin hams. The aroma of loin hams without mugwort were superior than that of loin hams with mugwort, and the juiciness of grade B loin hams were superior than that of grade E loin hams. But the color, taste, texture and palatability were not significantly different among loin hams.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.363-368
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• 1990

As a work on the investigation of the processing aptitude of the Korean soybean cultivars, the soybean curd was made from 19 Korean soybean cultivars on a laboratory scale. The yield, proximate composition and rheological and organoleptic property of the resultant soygean curd were analyzed. The yields of soybean curd were ranged from 262.33% to 311.63%, being positively correlated with the soluble protein contents of the recommended soybean cultivars (r=0.9621). The recovery rate of protein in Baekun and Yeunha to the soybean curd was 72.94%, 70.62%, respectively. More than 80% of lipid in soybeans of Yeunha, Dankyung, Danyeob was transferred to the soybean curd. Lightness of the soybean curd made from Baekun, Kwanggyo, Saeal, Hill was higher than that of the others. The mechanical hardness of the soybean curd was strongly correlated with the final moisture content of the soybean curd (r =-0.8312), but not with the protein content of the soybean (r=0.1848). In the organoleptic test for color, texture, flavor and overall preference of the resultant soybean curd, the quality of Dankyung, Namcheon, S-138, Baekun was evaluated highly.

• Food Science and Preservation
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• v.20 no.5
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• pp.636-642
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• 2013

Quality and sensory characteristics of tofu prepared with concentrated to 8 $^{\circ}Brix$ deep ground sea-like water (SW) were investigated to check the availability for coagulants. The tofu was coagulated with three kinds of commercially coagulant, such as $MgCl_2$, $CaSO_4$ and glucono-${\delta}$-lactone. Different amounts of SW and soybean milk were added: SW-20 g/L, SW-25 g/L and SW-30 g/L. The moisture content and pH were significantly lower in which preparation with glucono-${\delta}$-lactone coagulated tofu, and others has not significantly difference each other. The mineral contents in the coagulant influenced the mineral content of the tofu, which contained larger quantities of major minerals. However, the mineral content of the tofu was not affected of the mineral concentration in the coagulant. The L and b values of the tofu prepared with SW were not significantly different. The hardness of the tofu prepared with the commercial coagulants was significantly lower than that of the tofu produced with the SW. The sensory property was lower when the hardness was lower and higher. In conclusion, the quality characteristics of SW-prepared tofu were not significantly different from those of the tofu prepared with the commercial coagulants, but the texture and the taste of the SW-prepared tofu were excellent.

• Food Science and Preservation
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• v.24 no.2
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• pp.303-311
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• 2017

This study was performed to evaluate the quality characteristics and the antioxidant activities of yanggeng added with the aged black chestnut inner shells (ACI). The levels of ACI addition to Yanggeng were 0%, 1%, 3%, or 5%. The moisture content and the reducing sugar contents of Yanggeng increased with the amount of ACI. The pH of Yanggeng with ACI decreased with the amount of ACI, but the acidity increased. Depending on the amount of ACI added, the lightness (L) and yellowness (b) values of Yanggeng with ACI decreased in the Hunter color system, and the redness (a) value increased. Textural properties by TPA showed that hardness, springiness and chewiness decreased as increase in the amount of ACI added. Total phenol content in the Yanggeng added with ACI increased with the amount of ACI added. Increasing amount of ACI addition enhanced antioxidant activities of Yanggeng, as evidenced by DPPH radical scavenging activity and hydroxyl radical scavenging activity assays. In the preference test, Yanggeng added with 3% ACI showed the highest overall preference and texture. Based on these results, when 3% ACI was added to Yanggeng the quality characteristics, antioxidant property and sensory properties were excellent.

• Food Science and Preservation
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• v.22 no.6
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• pp.817-822
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• 2015

This study investigated the physical, textural, and sensory properties of strawberry jam with different amounts (0%, 14%, and 21%) of added rice mash. The soluble solids, pH, and total acidity values of the samples were found to be in the range of $53.00{\sim}65.33^{\circ}Brix$, 4.11~4.20 and 0.66~0.80%, respectively. Soluble solids and total acidity decreased significantly as the amount of rice mash was increased. The L-value, a-value, and b-value increased on increasing the amount of rice mash (p<0.05). The glucose contents of the samples ranged from 3.86 g to 4.13 g. The fructose, sucrose, and maltose contents significantly decreased (p<0.05). The organic acid content was measured and it was found that, oxalic acid was not in the control sample (0% rice mash). As the rice mash content was increased, the succinic acid content also increased (p<0.05), but the citric acid content decreased significantly (p<0.05). In the sensory evaluation, strawberry jam with rice mash showed superior spreading property than that of the control sample. Strawberry jam with 0% rice mash had the highest color and taste score. For the overall acceptability, strawberry jams with 0% and, 14% of rice mash were preferable to that with 21%.

• Food Science and Preservation
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• v.23 no.1
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• pp.27-33
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• 2016

This study investigated the effect of heat treatments on the quality characteristics of fresh-cut 'Romaine' lettuce by treating in hot water (45, 50, and $55^{\circ}C$) for 2 minutes. Sensory properties, respiration rate, ethylene production, microbial growth, browning index, total phenolics (TP), vitamin C, and antioxidant properties (DPPH, ABTS, and FRAP assays) of samples were evaluated after 5 days at $5^{\circ}C$. All heat treatment conditions tested in this study did not affect the change in TP after storage. Treatment at $45^{\circ}C$ enhanced respiration rate and ethylene production wheres decreased vitamin C content and antioxidant activities. There was no significant difference in browning index at $45^{\circ}C$ treatment. The rapid tissue softening occurred when treated with $55^{\circ}C$ hot water for 2 minutes. The $50^{\circ}C$ heat treatments exhibited the best quality index including texture and color, and inhibited microbial growth and browning after storage. In addition, the $50^{\circ}C$ heat treatment showed the highest vitamin C content and antioxidant activities (DPPH, ABTS, FRAP assay) after storage. Therefore, the $50^{\circ}C$ heat treatment can be used to maintain quality and antioxidant property of fresh-cut 'Romain' lettuce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.167-174
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• 2003

Physicochemical and sensory properties of turnip dongchimi were examined during fermentation at $0^{\circ}C$. Salt concentrations of dongchimi liquid were around 1.3% during fermentation. Greater decrease in pH and reducing sugar content in solid, and higher increase of acidity, turbidity and reducing sugar content in liquid were observed during fermentation. The acidity and pH at the optimal fermentation time, at the day 40 was observed 0.36% and pH 3.9, respectively Lactobacilli number, turbidity, anthocyanin content, the Hunter color L and a values were the greatest at the day 40 and then gradually decreased. The hardness and fracturability of turnip, determined by texture analyser, decreased during fermentation, while springiness increased. Sensory evaluation showed that the scores of color of purple, sweet taste, savory taste, and over-all preference of dongchimi were highest at the day 40. Score of overall preference of turnip dongchimi was the highest with 6.5 at the 40th day of fermentation, the optimum fermentation time, but the score until the day 60 was not significantly decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1285-1291
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• 2011

This study was conducted to evaluate the effect of lotus leaf and lotus root powder on the quality characteristics of sponge cake. Percentages of 4, 8 and 12% of two kinds of lotus powder were added to the batter based on flour content. Baking and cooling loss rate, volume and specific loaf volume, crumb color, texture, scanning electron microscopy (SEM) and sensory evaluation of the products were analyzed. The baking and cooling loss rate of the control was lower than cakes with added lotus leaf and lotus root powder. The volume of the control was the largest, and as the amount of lotus leaf and lotus root powder increased, volume and specific loaf volume became smaller. The lightness and yellowness values of the control were higher than those of the experimental cakes, and the loaves with 12% added lotus root powder showed the lowest value. Redness of the experimental cakes increased. In the textual property evaluation, hardness of the control and sponge cakes containing 4% lotus leaf, and lotus root powder appeared to have the lowest value. As the amount of lotus leaf and lotus root powder increased, hardness increased. Springiness showed the same tendency, but cohesiveness of the control revealed the lowest value. The structure of the cake crumb by SEM, revealed that the crumb cells and grains of the experimental cakes were opened and coarse, as the amount of lotus leaf and lotus root powders increased. In a sensory evaluation, sponge cakes containing lotus root powder were preferred rather than those with lotus leaf powder. As a result, good sponge cakes were prepared by adding 4% lotus leaf powder or 8% lotus root powder.