• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.730-736
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• 1997

Pasteurization of low salt dongchimi juice was studied for the effect of heating temperature and time on total viable counts and some physicochemical and sensory properties. The juice was prepared by fermentation of the radish at $20^{\circ}C$ in 0.5% NaCl solution. Heating the juice (pH 3.8) at $60{\sim}100^{\circ}C\;for\;5{\sim}30$ min caused little changes in pH and total acidity while the lightness (L value) was decreased and the turbidity, a and b values of color were increased as the heating temperature and time increased. The total viable counts of microorganisms was significantly decreased to 18 at $60^{\circ}C$ and 6 at $70^{\circ}C$ after 30 min heating and was not detected after heating at 90 and $100^{\circ}C$ for 10 min. The sensory test showed that heating up to $70^{\circ}C$ for 20 min caused a little cooked off-flavor. After storage of the pasteurized juices at $30^{\circ}C$ for 10 days, the pH, total acidity and color were changed little while the unheated juice changed significantly. The total viable counts of microorganisms was also remained initial level after pasteurization. Therefore pasteurization at $60^{\circ}C$ for 30 min or $70^{\circ}C$ for 20 min was recommendable in the aspects of storage stability and quality characteristics.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.792-798
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• 2002

Investigations on the microbiological, physicochemical, and sensory characteristics of seasoned Galbi using various packaging methods during storage at $-1^{\circ}C$ revealed no significant differences in pH values and acidities of seasoned Galbi depending on packaging methods and storage periods. Increments of thiobarbituric acid values of seasoned Galbi with non-evacuated packaging and modified atmosphere packaging were superior to those of vacuum packaging and double-film vacuum packaging during storage. Seasoned Galbi with non-evacuated packaging showed the highest volatile basic nitrogen value, and total plate count significantly increased compared to other packaging methods after 15 days storage. Coliform bacteria showed an average count of 2.35 log CFU/g at the beginning of storage, which increased slightly from 7 to 15 days, and was maintained under 4.0 log CFU/g after 15 days storage. The sensory evaluation revealed that non-evacuated packaging scored relatively lower than other methods in color, flavor, off-odor, and overall acceptability after storage.

• Food Science of Animal Resources
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• v.22 no.2
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• pp.145-150
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• 2002

Effects of dietary 0.6% activated carbon on pork quality were investigated with six pigs (Landrace ${\times}$ Large White ${\times}$ Duroc) that were randomly selected from uterine brothers. Three pigs, for control group, were fed with a commercial pig diet for 4 weeks before slaughter whereas the others were fed a diet added 0.6 % activated carbon for treatment group. Pork loin and belly cuts were collected at 24 hrs postmortem, and transfered to laboratory to measure quality characteristics. There were no significant differences in muscle pH and cooking loss % of pork loin and belly. Also there were no significant differences in adhesiveness, cohesiveness, gummness and brittleness between thed treatment and control. However, hardness and springiness of samples from the treatment were significantly higher (p<0.05) than those of control. There were no significant differences in scores of aroma, color and off-flavor assessed by a penal test. Treatment group showed a significantly higher acceptability (p<0.05) compared to the control group. Samples of the treatment had higher concentrations of oleic acid, linoleic acid and linolenic acid, wheres samples of control showed a higher concentration of palmitic acid (p<0.05). Belly cuts of control group showed a significantly higher concentration of stearic acid compared to the treatment group. These results suggested that hardness, springiness and acceptability of pork could be improved, and concentration of unsaturated fat acid in pork muscle might be increased by dietary 0.6 % activated carbon.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1189-1196
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• 2014

This study investigated the effects of saltwort powder on the antioxidant activity and quality characteristics of patties added with saltwort powder. Patties were prepared with different amounts (0, 1, 2, and 3%) of saltwort powder. The total phenolic content, DPPH free radical scavenging activity, and pH of patties increased with increasing saltwort powder content (P<0.05). In particular, the moisture content and cooking loss of the group added with 2% saltwort powder were the highest and lowest, respectively (P<0.05). As the content of saltwort powder increased, $L^*$ and $a^*$ values decreased while $b^*$ value increased. Texture analysis showed that the hardness, chewiness, and gumminess of the control group were lower than those of the treated group (P<0.05). Consumer acceptability showed that 1% and 2% saltwort powder groups scored higher in terms of overall preference, appearance, color, taste, and texture compared to the other groups. Characteristic intensity rating of saltwort patties showed that as more saltwort powder was added, saltwort taste intensified; however, the increase did not affect juiciness, off flavor, or salty taste of the patties. Judging from the results, it was concluded that the addition of saltwort powder to patties in processing can enhance the preference, quality, and antioxidant activities of the patties, which elevates the value of patties.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.293-304
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• 2012

This study was conducted to improve the sensory acceptability of modified Kochujang added with Tofu powder(25%, 50%, 75%, 100%) instead of Meju powder. These Kochujang samples were fermented for 45 days and examined in physicochemical properties and sensory characteristics. The result was as follows. Moisture content of the control was higher than that of the other Tofu powder Kochujang samples, which lasted for 30 days of storage. Moisture contents of all samples were increased by storage time. The pH of Kochujang added with Tofu powder was higher than that of the control. In general, pH values were decreased by storage time. Acidity decreased with Tofu powder increased while it generally increased with more storage time. In the lightness(L value), redness(a value) and yellowness(b value), control Kochujang was the lowest. There were no significant differences in the reducing sugar contents except 45 days. In sensory evaluation, color of Kochujang was evaluated light and off-flavor got weaker with Tofu powder increased. In the sensory attributes of odor, taste, overall acceptability, Tofu powder added Kochujang had high scores than the control, and especially 100% TP Kochujang had the best score.

• Culinary science and hospitality research
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• v.15 no.1
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• pp.128-136
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• 2009

In this study, Korean wheat wet noodles were prepared with 1, 3, 5, and 7% pomegranate cortex powder(PGCP). The samples and a control were compared in terms of quality characteristics, including cooking properties, colors, textural characteristics, and sensory evaluation in order to determine the optimal ratio of PGCP in the formulation. With regard to the cooking properties, weight, volume, and water absorption decreased with PGCP content increased. As for colors, the PGCP content L, a, b value increased. For the textural characteristics, springiness and cohesiveness were not significantly different among the samples. The PGCP samples had significantly higher hardness, chewiness, brittleness, and gumminess than the control group. However, strength showed the reverse effect. In the sensory evaluation, the control group had significantly higher scores in colors, texture, and chewiness as compared to the PGCP samples. Overall acceptability decreased with PGCP content increased while bitterness, astringency, and off-flavor increased. Furthermore, saltiness and gumminess were not significantly different among the samples. In conclusion, the results show that 1% of PGCP was proved very useful as a substitute for Korean wheat flour in the production of wet noodles, providing good nutritional and functional properties.

• Food Science and Preservation
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• v.14 no.6
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• pp.578-583
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• 2007

This study was conducted to evaluate the effect of high $CO_2$ pre-storage treatment on the quality of tomatoes (Lycopersicon esculentum Mill.) during ripening. Tomatoes at different maturity stage of breaker and pink were treated in air, or $CO_2$ (25, 50, 100%) for 24 hr at $20^{\circ}C$ before ripening in air at $20^{\circ}C$. Change of surface colour and softening were reduced by high $CO_2$ treatment of all concentrations. This effect of $CO_2$ on the colour and softening was higher in breaker fruit than pink fruit. $CO_2$ concentration of $25{\sim}100%$ did not affect on soluble solids content during ripening period. Titratable acidity of breaker tomatoes were reduced by 100% $CO_2$ treatment. High $CO_2$ treatment slightly reduced sweetness of breaker tomatoes. Acidity and texture of tomatoes increased with high $CO_2$ treatment. Off-flavour was denoted by $CO_2$ treatment in pink tomatoes. The external $CO_2$ injury developed after 22 days at $20^{\circ}C$ in pink tomatoes when treated with ${\geq}25%$ $CO_2$ and in breaker tomatoes with ${\geq}50%$ $CO_2$.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.557-561
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• 2005

Effects of natural preservatives on quality and shelf-life of fresh pork were investigated by evaluating changes in physicochemical properties, sensory evaluation, and mcrobial properties during storage. Acidity and VBN values of pork with preservatives were lower than those of control. Total bacterial count of pork with preservatives was significantly lower than that of control during storage. Sensory results showed pork with preservatives had lower sensory color and off-flavor scores than control. Changes in pH, VBN, total bacterial count, coliform group, and sensory evaluation revealed pork with preservatives showed less quality changes than control during storage, regardless of storage temperature. Results indicated that addition of preservatives to pork increased shelf-life by 7 days at $4^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.74-79
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• 1976

Two rice varieties in Korea, an Indica type 'Tongil' and a Japonica type 'Jinheung', were stored at $5^{\circ}C$ and $30^{\circ}C$ for six months and the changes in organoleptic quality and lipid components were investigated to obtain the following results. In storage, both varieties brought about increases of hardness, cohesiveness and gumminess, and a decrease of adhesiveness among textural parameters of cooked rice. Storage at $5^{\circ}C$ showed no change in organoleptic quality but storage at $30^{\circ}C$ caused the occurrence of off-flavor in both varieties and a marked decrease of stickiness in Jinheung. Rice samples before storage contained 5-times more free lipids than bound lipids and free lipid content of Tongil was $70{\sim}80%$ of Jinheung. In storage, bound lipids tended to increase slowly while free lipids increased in both varieties at $5^{\circ}C$ and tended to increase in Tongil and to decrease in Jinheung at $30^{\circ}C$. In free lipid fractions of rice samples before storage were found 9 components including triglycerides, free fatty acids and sterol esters and in bound lipid fractions were found 8 components including free fatty acids and sterol esters, as the major components. In storage, changes in lipid components were more remarkable in free lipids than in bound lipids and in Jinheung than in Tongil. It was, therefore, concluded that Tongil variety had a better storage stability than Jinheung variety and the deterioration of rice quality occurred mainly in free lipid fractions during storage.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.166-172
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• 2003

Changes in the number of microorganisms, chemical composition, and sensory quality of chungkukjang by gamma-irradiation up to 120 kGy were investigated. The total viable cell counts in chungkukjang irradiated with 10 kGy decreased from $10^9\;CFU/g$ of the control to $10^5\;CFU/g$. Proximate chemical composition and pH of chungkukjang were not much affected by irradiation. Acidity of chungkukjang decreased by irradiation with over 20 kGy. Fatty acid contents of chungkukjang irradiated under 20 kGy were the same as those of the nonirradiated ones. Polyunsaturated fatty acids content, decreased at over 40 kGy. The color and odor of chungkukjang were not significantly affected by irradiation up to 20 kGy. Unpalatable odor (p<0.01), off-flavor (p<0.001), and fish-odor (p<0.001) increased, and brown intensity (p<0.05) and acceptability (p<0.001) decreased at over 20 kGy. Results indicate 20 kGy is sufficient to decrease the microbial count of chungkukjang and prevent decrease in the content of polyunsaturated fatty acids.