• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.338-345
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• 1987

The Physicochemical properties of six varieties of domestic orange and orange juices which were grown and produced in Korea, were analyzed their qualities, including taste evaluation based on the amount and the ratio of sugar and acid The physicochemical properties of mandarin were as follows soluble solid $10{\sim}11^{\circ}$ Bx, total acidity $0.76{\sim}1.20%$ ratio of sugar and acid $7.9{\sim}13.8$. Sugars of orange are mainly composed of sucrose, glucose, fructose. The sucrose content of mandarin was a little higher than that of sweet orange. The organic acids in orange were mainly citrate and malate. The content of these two acid in oranges were 0.8-1.4%. Mandarin type oranges tastes more sour than sweet orange. Hesperdin existed 30.8-67.5mg% in oranges. Naringin, one of the bitter components. was not detected in both varieties. The optimum sweetness and acid content were determined based on the results of sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.430-436
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• 2016

Solid phase microextraction and gas chromatography-mass spectrometry (SPME/GC-MS), electronic nose, and electronic tongue were used to characterize the sensory profiles of cider vinegars from Korea (K1-2), China (C1-2), Japan (J1-2), and US (U1-2). SPME-GC/MS detected acetic acid as the common volatile compound in all vinegars, in addition to isovaleric acid, octanoic acid, and phenethyl acetate. Acids and acetic esters were the major components of Korean and US vinegar samples, respectively. Chinese vinegars had high ethyl acetate content, while Japanese samples were characterized by a low content of acetic acid. Principal component analysis (PCA) pattern provided a clear categorical discrimination of Chinese vinegars by E-nose and E-tongue analyses. The instrumental sensory scores and the taste attributes for flavor ($r^2=0.9431$), sourness ($r^2=0.9515$), and sweetness ($r^2=0.8325$) were highly correlated. Therefore, SPME/GC-MS, E-nose, and E-tongue analyses may be useful tools to discriminate the sensory profiles of cider vinegars of different origins.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.349-354
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• 2017

The geographical origins of raw ginseng (RG) were discriminated using an electronic tongue. Taste screening, DFA (discriminant function analysis), and CDA (canonical discriminant analysis) were used to statistically analyze the data. The taste profile patterns of umami, bitterness, and sweetness of the Korean RG was different from those of the Chinese RG. The Korean RG was stronger than the Chinese RG regarding the taste of umami. DFA discriminated the geographical origins of 154 samples, with a few overlapping samples, between the Korean and Chinese RG. CDA showed that the accuracy of origin discrimination for the Korean and Chinese RGs were 87.01 and 94.81%, respectively. The final accuracy of origin discrimination was 90.91%. The distance between the centroids of each group was 2.7463. Thus, the electronic tongue analysis can be used to efficiently differentiate the geographical origins of RG.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.50-58
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• 2014

Makgeolli, known as takju, is a traditional alcoholic beverage which is native in Korea. It is made from various rice and other cereals. This study is carried out to compare the physicochemical characteristics and functional quality of makgeolli from various rice cultivars according to different amylose contents and amylopectin compositions. The 'Goami2', 'Goami3', and 'Goami4' have high amylose contents and lower proportional degrees of polymerization (DP) 6~12 and higher proportions of DP 13~24 in amylopectin of milled rice. Various variations are shown in pasting properties (viscosities) and gelatinization characteristics, and it is supposed to be related to both the amylose contents and the amylopectin compositions of raw rice. The makgeolli is being manufactured by using the 2-step-brewing method. The makgeolli is analyzed for alcohol contents, pH levels, total acids, Hunter color values and organic acid compositions. The makgeolli of 'Goami2', 'Goami3', and 'Goami4' have showed higher makgeolli yields, lower ethanol contents and less sweetness than other cultivars, and they also have high non-digestible carbohydrates contents which are derived from their high non-digestible carbohydrates contents in milled rice. Therefore, we are able to suggest that it is necessary to improve the makgeolli fermentation processes of 'Goami2', 'Goami3', and 'Goami4'.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.31-42
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• 2014

This study was conducted to evaluate the effect of gamma irradiation (0.4, 0.6, 0.8, 1 and 1.5 kGy) on the microbiological, physicochemical and sensory qualities of imported orange during storage at $3^{\circ}C$ for 60 days. Total aerobic bacteria and yeast/mold counts in non-irradiated oranges were 3.59 and 3.75 log CFU/g, and those counts in irradiated oranges at 1.5 kGy were decreased by 1.75 and 2.26 log CFU/g, respectively. Moreover, those counts were decreased significantly according to a dose-dependent manner after gamma irradiation. The pH revealed no significant difference between the control and irradiated samples; however, titratable acidity was decreased significantly according to a dose-dependent manner and storage time. The vitamin C contents were decreased significantly according to a dose-dependent manner and storage time after gamma irradiation. Further, sensory evaluation testing revealed no significant difference between the control and irradiated samples, except 1.5 kGy. Samples irradiated at 1.5 kGy had the lowest values in color, sweetness, sourness, flavor, texture and overall acceptance. The results suggest that gamma irradiation was effective for ensuring microbiological safety; however, irradiated oranges at 1 and 1.5 kGy did not have good physicochemical and sensory qualities. Therefore, we can use the sample irradiated at 0.4~0.6 kGy as optimum-dose to be minimize on quality changes.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.604-609
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• 2002

The sensory properties and flavor components of the white bread added with arrowroot juice. The lightness of bread crumb decreased significantly as arrowroot juice was added. While the yellowness increased slightly, redness increased remarkably. The hardness, chewiness and adhesiveness of the white bread added with arrowroot juice increased more than those of the control bread, but they had no statistical significance. While the gumminess increased significantly and springiness decreased significantly, the cohesiveness did not indicate significant differences among the comparison groups. In sensory evaluation, the texture, flavor and sweetness did not indicate significant difference among the comparison groups, while the color and overall acceptability indicated significant difference. The optimum concentration of arrowroot juice in the white bread was 25% based on the sensory evaluation scores. The main flavors components of the white bread added with 25% arrowroot juice were compounds translated by arrowroot juice and the compounds formed by amino-carbonyl reaction. The translated flavors were methoxy phenol, ${\beta}-damascenone$, benzylcyanide, and menthofuran. The compounds formed by amino-carbonyl reaction were alkyl pyrazines, pyrroles and furans.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1251-1257
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• 2000

Red pepper powder (Capsicum annuum L.) is one of the most important ingredients for making kimchi. Various aspects of the quality of the red pepper powders (RPP) produced in Korea depending on the varieties and producing districts were compared. The evaluated intrinsic elements were vitamin C, carotenoid, capsaicinoid and free sugar contents and the extrinsic element was ASTA (American Spice Trade Association) colors. The vitamin C content was the highest in Johong (230 mg%) RPP among the varieties and Youngyang (263 mg%) RPP among the producing districts. Myungpum RPP that contains high level of carotenoids showed increased level of ASTA color, it exhibited positive relationship between carotenoid contents and ASTA color. Capsaicinoid level in RPP was the highest in var. Chungyang (126.1 mg%) that was usually used soup and pungent cook. Free sugar contents which is related to sweetness were the highest in Youngyang RPP Youngyang RPP that preferentially used in the preparation of kimchi showed the highest levels in vitamin C, carotenoid, ASTA color, and free sugar contents, but the contents of capsaicinoid was the lowest.

• Current Research on Agriculture and Life Sciences
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• v.31 no.3
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• pp.182-192
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• 2013

Since the Korean apple industry needs to expand its export market in Southeast Asia, this study investigates the attributes of Korean apples affecting consumer preference in Indonesia, Malaysia, Singapore, and Thailand. Based on an Importance-Preference analysis, the results are summarized as follows. First, price is the most important determinant for purchasing Korean apples by Southeast Asian consumers, except in Malaysia. Second, managing the intrinsic(sweetness and chewing texture) and extrinsic(surface and color) factors needs to be well maintained. Third, the priority of the marketing factor(wrapping) should be lowered. Fourth, while the importance of extrinsic factors(shape and size) is low, satisfaction is high, so these factors need to be managed to avoid overkill. Overall, Korean apples should have their own merits with an appropriate proper price, while maintaining a high quality. The results of this paper may provide suitable strategies for promoting apple exports to Southeast Asia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.128-136
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• 2015

This study investigated the effects of low-dose electron beam irradiation treatment on physicochemical and sensorial properties of imported navel oranges during storage at $3^{\circ}C$ for 45 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, and changes in their color values, hardness, Brix/acid ratio, total sugar contents, reducing sugar contents, vitamin C contents, and sensory evaluation were investigated. There were no significant differences between non-irradiated and irradiated samples in terms of color values, Brix/acid ratio, total sugar contents, total reducing sugar contents, and vitamin C contents. Hardness of irradiated sample at 1 kGy decreased significantly in the early storage period, but the difference between non-irradiated and irradiated samples decreased again at the end of storage. For the sensory evaluation, scores of color, sweetness, flavor, and overall acceptability decreased as irradiation dose and storage period increased. Samples irradiated at over 0.8 kGy showed low preference in all scores except color. These results suggest that electron beam irradiation below 0.6 kGy does not affect physicochemical and sensory properties; thus, electron beam irradiation up to 0.6 kGy in imported navel oranges is optimum for minimizing quality changes and disinfestation treatment simultaneously.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1205-1210
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• 2007

Texture properties of a Korean rice cake (Karedduk) added with carbohydrate materials after 0, 2, 6, 24 and 30 hrs of storage at $5^{\circ}C$ were investigated using textural characteristics and sensory descriptive analysis. Carbohydrate materials such as powdered sugar, trehalose, fructooligosaccharide (95%), isomalto, healtholigo, and galactooligosaccharide (50%) were added in 0, 1, 5 and 10% levels to dry rice flour. The texture profile analysis by Texture Analyzer revealed that adhesiveness and cohesiveness of the Korean rice cake (Karedduk) added with carbohydrate materials were similar to those of the control in trends, while hardness was low compared to the control except for fructooligosaccharide (95%) 5% and healtholigo 1% addition. The hardness and sweetness by sensory characteristics were significantly different compared to the control. Instrumental hardness was correlated with sensory hardness. Lastly, the Korean rice cake (Karedduk) added with carbohydrate materials except fructooligosaccharide (95%) 5% and healtholigo 1% addition was effective in delaying retrogradation.