• Food Science of Animal Resources
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• v.24 no.4
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• pp.361-366
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• 2004

Physicochemical and textural properties, and sensory evaluation of low-fat sausages (LFSs) manufactured with 0.3 and 0.6％ chitosan were investigated and compared with those of regular-fat sausages (RFSs). Although the batter pH was not changed with the addition of chitosan (p>0.05), product pH was reduced (p>0.05) with the addition of chitosan up to 0.6％. Proximate composition and cooking loss (％) were not affected by the addition of chitosan. Expressible moisture 1r91ues (EM, ％) of LESs were lower (p<0.05) than those of RFSs, but not affected by the addition of chitosan. The addition of chitosan in the sausage formulation became harder, springier and more cohesive (p<0.05), whereas, no differences were observed (p>0.05) in these values of sausages containing between 0.3 and 0.6％. Batter viscosity was not affected by the addition of chitosan, but LESs with or without chitosan had lower viscosity than RFSs due to high moisture (％). Sensory evaluation results showed that LFSs containing 0.3％ chitosan had most parameters similar to those of low-fat control. These results indicated that chitosan at the level of 0.3％ can be used for the manufacture of LFSs without quality defect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1055-1061
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• 2014

Innovative freezing technology is currently applied to preserve foodstuffs for long-term storage. Generally, the quality of frozen food is closely related to the types of freezing and thawing processes. In this study, we characterized the physicochemical properties of onions depending on freezing rate. When onions were frozen at $-40^{\circ}C$, freezing rates were 0.1, 0.5, and $0.7^{\circ}C/min$ depending on air-blast quick freezer mode. Onions were thawed by microwave irradiation at 400 W. Hardness of onion dramatically decreased after freezing and thawing compared with blanched onion. However, the fastest freezing rate did not affect hardness. Thawing loss of onion decreased with a faster freezing rate. For morphological observation, onion frozen at a faster rate showed a smaller ice-crystal size. Vitamin C content decreased upon blanching or freezing, but there was no significant difference according to freezing rate. Although free sugar content also decreased upon blanching and freezing, its highest content was at $0.7^{\circ}C/min$ freezing. Among organic acids, malic acid content was highest at $0.7^{\circ}C/min$ freezing. Based on this study, it could be suggested that a faster freezing rate is effective to improve frozen food quality in accordance with preventing tissue damage or minimizing destruction of nutrients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.792-797
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• 2008

The purpose of this study was to investigate the effects of adding various amounts of ingredients on the physicochemical and sensory characteristics of Bokbunja-jelly. The proximate composition of Bokbunja-jelly was 19.0% for the moisture and 0.8% for the crude protein. The Hunter L-values of Bokbunja-jelly prepared by adding 10 g RME or 120 g sucrose were higher than that of Bokbunja-jelly prepared by adding 20 g RME or 100 g sucrose. The Hunter b-values of Bokbunja-jelly prepared by adding 20 g RME or 120 g sucrose was higher than that of Bokbunja-jelly prepared by adding 10 g RME or 120 g sucrose. The hardness and chewiness were increased with decreasing Rubus coreanus Miquel extracts. According to the results of the sensory evaluation, no significant differences in flavor, sweetness, hardness, elasticity and overall qualities were found. According to the results of physicochemical properties and sensory evaluation, the optimal recipe for preparation of Bokbunja-jelly was determined to be 240 g water, 120 g sugar, 110 g glucose syrup, 4 g agar, 20 g Rubus coreanus Miquel extracts and 0.3 g Rubus coreanus Miquel flavor.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.256-263
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• 2001

Physicochemical characteristics of kochujang prepared with meju, koji and mixture of meju and koji were analyzed during fermentation in order to improve quality of traditional sikhe kochujang. Amino nitrogen content, an index of kochujang quality, was remarkably higher in kochujang prepared with p-2 koji, p-1 koji, mixture of p-2 koji and meju. Titratible acidity of kochujang slightly increased and pH of kochujang increased until 40 days of fermentation and then decreased there after. Citric acid was found as a major organic acid followed in decreasing order by malic, oxalic, succinic, acetic and lactic acids. As a free sugar, maltose, glucose and fructose were detected. Free sugar content was higher in kochujang prepared with p-1 koji than the others. The major free amino acids were aspartic acid, glutamic acid, alanine, phenylalanine and arginine, and total free amino acid content was higher in kochujang prepared with koji, and mixture of meju and koji than the one with traditional meju only. In sensory evaluation, all tested groups did not show a significant difference. This result indicates that addition of koji to sikhe kochujang influences on taste components like free sugars and free amino acids, but decisively not on the sensory properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.717-724
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• 2011

We evaluated the physicochemical properties of four varieties of muskmelons (Thankyou, Beauty, Picnic, Sympony) during storage at $7^{\circ}C$. We stored Thankyou, Sympony, and Beauty varieties for 28 days at $7^{\circ}C$, while the Picnic variety was stored for 21 days. After the storage period, the mineral content of the Thankyou variety changed the least, by 2.36%, while that of the Sympony and Picnic varieties changed the most. The Thankyou variety also lost the least amount of free sugar content during storage. The Sympony variety had the highest vitamin C content at the beginning of the storage (26.0 mg%/100 g). After 14 days of storage, there was little difference in the vitamin C content of the varieties, which ranged from 11.5 to 12.5 mg%/100 g. The Picnic variety, which had the highest respiratory quotient, indicated lower storability than the other varieties. In a sensory evaluation, the Thankyou variety was considered to be the best in terms of consumer preference. However, the stem water loss seen in this variety tends to be the first thing that consumers see and may determine its merchantable quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1881-1888
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• 2014

Pre-thermal treatment is important to minimize quality changes during main cooking or storage. In this study, to optimize pre-thermal treatment of carrots, three types of pre-thermal treatments were applied to carrots and quality changes such as physicochemical, nutritional, or sensory properties were observed. Washed and sliced carrots were thermally treated by hot-water immersion ($100^{\circ}C$, 1~10 min), steaming ($100^{\circ}C$, 1~10 min), and stir-frying with oil (10~80 sec). Carrot tissue was maintained until 2 min hot-water immersion or steaming, and they were damaged by just 30 sec of stir-frying. Color and hardness were significantly affected by treatment time and temperature. Color was completely changed after 5 min and 7 min by hot-water and steam treatments, respectively. Hardness decreased to 44% compared with fresh carrot (4,500 g) after 1 min, 3 min, and 20 sec of hot-water, steam, and stir-frying, respectively. For nutritional changes, ascorbic acid, organic acid, and peroxide activity were reduced by all treatments compared with fresh carrot. Especially, succinic acid was dramatically reduced by hot-water treatment. Otherwise, free sugar contents were increased with greater treatment time in all samples. In this study, pre-thermal treatment of carrot was optimal at 2 min steaming treatment.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.205-219
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• 2012

The purpose of this study is to make a correlation analysis between mechanical characteristics and sensory characteristics of puffer fish fillet under storage conditions and to find out those quality characteristics. With the storage time, VBN increased while color, smell and texture values decreased. As the appearance, the fish showed excellent quality stored at $4^{\circ}C$ for 8-12 hours, at $12^{\circ}C$ for 4-8 hours and at $20^{\circ}C$ for 4 hours. When the L value increased, color preference in sensory results decreased in correlation physicochemical properties, mechanical properties and sensory properties of puffer fish fillet. However, mechanical properties and sensory evaluation showed a different aspect. When the higher temperature, redness(a-value) decreased. Regardless of storage temperature, yellowness (b-value) increased. In the results of the hardness, the value was higher, the sensory showed the better texture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.362-366
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• 2008

This study was carried to investigate effects of gamma irradiation on the moisture, crude protein, crude lipid, 2-thiobarbituric acid (TBA) values, color stability, texture, and sensory properties of restructured pork jerky. Restructured pork jerky was irradiated at dose levels of 0, 3, 5, 7 and 10 kGy with a use Co-60 source. There were no significant differences in the moisture, crude protein, crude lipid contents, and TBA values. However, as doses of gamma irradiation increased, the redness (a-value) of restructure pork jerky increased whereas shear force of restructure pork jerky was decreased by gamma irradiation. Sensory evaluation showed that sensory scores were reduced by gamma irradiation. Therefore, gamma irradiation could be an effective means to improve color and texture of restructured pork jerky, but only with proper consideration for sensory quality.

• Food Science and Preservation
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• v.13 no.5
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• pp.538-542
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• 2006

Physicochemical properties and positional distribution of Hallabong Tangor (Citrus Kiyomi ${\times}$ ponkan) cultivated in heated greenhouse were investigated. About 90% of Hallabong produce fruit within the range of $250{\sim}400g$ fruit weight on a tree, larger fruits were mainly consisted of $400{\sim}450g$ in M16A, a variant species of Hallabong, due to younger tree and fruit thinning. Nevertheless fruit sizes of M16A were larger than Hallabong, and peel thickness of M16A (3.29 mm) was thinner than that of Hallabong (3.51 mm). Hardness of m6h was 994.69g-force, compared to 832.8 g-force of Hallabong on the average. Soluble solids and acid content of Hallabong were $12.20{\sim}12.98^{\circ}Brix$ and $1.08{\sim}1.14%$, while those of M16A were $1.48{\sim}12.63^{\circ}Brix$ and $0.92{\sim}1.00%$, respectively. Vitamin C content of Hallabong was $71.30{\sim}78.77 mg/100 g$, compared to $64.40{\sim}68.01mg/100g$ in M16A. Soluble solid in the part of stem was lower than that of end part among the same segment. Fruit size in the upper part of the tree was larger, the peel was thicket and flesh ratio was lower than the middle or lower part. However, soluble solids and acid content were high, due to cumulative sunshine during cultivation.

• Food Science and Preservation
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• v.21 no.4
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• pp.491-499
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• 2014

Changes in various physicochemical and sensory characteristics of Samgyetang retorted at the $F_0$ values of 4.0 (F4), 7.0 (F7), and 10.0 (F10) were investigated during storage at $25^{\circ}C$ for 12 months. The pH level tended to decrease in all the treatments with the increase of the storage time, but no significant difference in the extent of the decrease was observed among the treatments. The values of volatile basic nitrogen, thiobarbituric reactive substances, and carbonyl contents increased rapidly over the storage period in the order of F4 > F7 > F10. The viscosity decreased most sharply between month 0 and month 2, after which the rate of increase declined. The oxygen concentration in the headspace of the retort pouch of the Samgyetang was higher for the samples retorted at higher $F_0$ values. In the sensory tests, the scores of the samples retorted at higher $F_0$ values tended to be lower, but all the characteristics of the samples, except for the texture of the T10 samples, were evaluated with scores higher than 5.0, the limit of marketability, over the storage time. In conclusion, the quality of the Samgyetang samples treated at higher $F_0$ values deteriorated more noticeably during storage.