• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.341-348
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• 1991

Physicochemical properties and gelatinization patterns of defatted and lipid-reintroduced moist (Hwangmi) and dry (Suwon 147) type sweet potato starches were investigated. Starch granules of sweet potato were polygonal and round, and the sizes of starch granules ranged $5{\sim}13\;{\mu}m$. All starches showed Ca type in X-ray diffraction but relative crystallinity was decreased by defatting and reintroduction. The amylose content of defatted starches increased, but that of lipid-reintroduced starches decreased. The swelling power and solubility at each temperature increased by defatting, but decreased by reintroduction. Transmittance of Hwangmi and Suwon 147 showed a rapid increase at $60,\;65^{\circ}C$, respectively. The initial pasting temperature by amylograph of Hwangmi and Suwon 147 were $67.5^{\circ}C\;and\;72.7^{\circ}C$, respectively. The peak viscosity and the height at $50^{\circ}C$ on amylogram of Hwangmi were lower than those of Suwon 147. Hot paste viscosity and setback decreased by defatting but setbak and consistency drastically increased by reintroduction. The peak temperature for gelatinization by the DSC was $65.7^{\circ}C$ for Hwangmi and $68.5^{\circ}C$ for Suwon 147. The gelatinization temperature and enthalpy of the DSC decreased and amylose-lipid melting peak was lost by defatting. The gelatinization temperature and enthalpy decreased by reintroduction.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.556-565
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• 2014

In this study, we evaluated changes in physicochemical properties, total phenol and isoflavone contents, and antioxidant activity during soymilk fermentation by a potential probiotic Lactobacillus plantarum P1201. The P1201 strain showed survival rates of 58.14% and 62.22% after 4 h exposure to acid and artificial gastric acid conditions (pH 2.5), respectively. The optimal conditions for soy-yogurt fermentation by L. plantarum were determined to be as follows: temperature of $35^{\circ}C$, seed volume of 5.0%, and sucrose content of 10.0%. The total phenol and isoflavone contents and antioxidant activity were higher in soy-powder milk (SPM) yogurt than soymilk yogurt. In particular, the highest levels of isoflavone-aglycones, such as daidzein, glycitein, and genistein (91.50, 12.34, and $61.39{\mu}g/g$, respectively), were observed after 48 h of SPM fermentation. Thus, these results suggest that the soy-yogurt extract could be used as a potential source of natural antioxidants in food.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.486-491
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• 2016

Efficacy of dielectric barrier discharge-cold plasma treatment (DBD-CPT) for microbial decontamination of onion powder was evaluated. Onion powder, inoculated with Escherichia coli O157:H7, Salmonella Enteritidis, or Listeria monocytogenes, was treated with helium DBD-CPT. DBD-CPT (9 kV, 20 min) inhibited E. coli O157:H7, S. Enteritidis, and L. monocytogenes by $1.4{\pm}0.5$, $2.3{\pm}0.3$, and $1.2{\pm}0.0log\;CFU/cm^2$, respectively. The inactivation levels of E. coli O157:H7, S. Enteritidis and L. monocytogenes increased by $2.2{\pm}0.1$, $2.5{\pm}0.1$ and $1.9{\pm}0.3log\;CFU/cm^2$, respectively, as water activity increased from 0.4 to 0.8, and increased by $2.3{\pm}0.4$, $2.1{\pm}0.1$ and $1.6{\pm}0.1log\;CFU/cm^2$, respectively, as the particle size increased from 0.3 to $1.0cm^2$. Neither the ascorbic acid and quercetin concentrations nor the color of onion powder was changed by DBD-CPT (p>0.05). These results demonstrate the potential for application of DBD-CPT in improving microbiological safety of onion powder while preserving the physicochemical properties.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.421-429
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• 2017

In this study, we investigated the effect of roasting temperature on nutrient content, digestive enzyme activities, and antioxidative properties of sesame seed juice. The sesame seeds were either roasted at 160, 200, and $240^{\circ}C$ or not roasted, and the juice was extracted using a low-speed juice extractor. Owing to the short duration of roasting, benzo[a]pyrene were not detected and trans fatty acids were negligible detected in all sesame seed juices. The sesame seed juice contained abundant nutrients such as minerals, vitamins, and fatty acids. The contents of minerals, vitamin B1 and B3, and sesamol increased with increase in roasting temperature; however, the levels of fatty acids, vitamin B2, sesamin, and sesamolin decreased. In addition, the antioxidant content and antioxidative activities of sesame seed juice increased with increase in roasting temperature. Therefore, these results suggest that roasted sesame seed juice possesses high antioxidative activities, which may be beneficial for preventing oxidative damage in the body.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.83-91
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• 2018

Baekseolgi made with arrowroot flour (AF, 0 to 15% of rice flour) was steamed to examine the effect of heating on its antioxidant activity and physicochemical properties. Despite the presence of abundant dietary fiber and superior water-holding capacity of AF, moisture in baekseolgi was not significantly increased. This could partly be attributed to AF having 50% less moisture content than rice flour. Hence, hardness of baekseolgi was also not significantly altered. Total reducing capacity and flavonoid content of baekseolgi increased proportionally with the increase in AF addition. However, these values were lower than the predicted values calculated from the antioxidant activities of heated AF, which was more apparent in total reducing capacity. This indicated that the stability of non-phenolic reducing compounds in AF was lower than that of the phenolic compounds. Thermally processed baekseolgi made with 9% AF exhibited antioxidant activity without noticeable loss in the quality of the product.

• Journal of Food Hygiene and Safety
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• v.32 no.6
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• pp.521-530
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• 2017

The purpose of this study was to examine the physicochemical and antioxidant properties of cookies with mealworm (Tenebrio molitor) and black soybean powder. The leavening rates, and loss ratios were significantly increased with adding up the amount of mealworm powder (p < 0.05). The total polyphenol, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging ability, FRAP activity (ferric reducing antioxidant power) and ABTS radical scavenging ability (2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid) were all significantly increased as mealworm powder contents increased. In addition, cookies containing both mealworm and black soybean powder were higher in total polyphenol, DPPH and ABTS radical scavenging abilities than cookies containing only mealworm powder (p < 0.05).

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.659-665
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• 2006

The effects of resistant starches on the quality characteristics of cookies were investigated by the physicochemical, instrumental and sensory properties of RS-added flours and cookies. Retrograded RS3 by autoclaving-cooling cycle and cross-linked RS4 after annealing treatment were used. The protein content of RS-added flour decreased, but the ash content of RS4-added flour increased slightly with increasing RS content. The RS levels of wheat flour, RS3- and RS4-added flours were 7.0%, 9.6-13.4% and 11.5-17.9%, respectively. The swelling powers of RS-added flours at 80$^{\circ}C$ decreased, but the solubility of RS3-added flour increased by 2-3 fold compared to that of control flour. Initial pasting temperature increased, but peak, holding, and final viscosities decreased with increasing RS content. The retrogradation degree of RS-added flours was lowered, because of the decreased consistency and breakdown viscosity. The yellowness of RS3-added flour increased with increasing RS3 content which induced browning reaction during baking. On the sensory test, RS-added cookies were significantly different in shape, color and overall quality (p<0.05), and their texture also affected. Overall quality was higher in peanut cookies than in AACC standard cookies and RS addition (up to 30%, w/w), regardless of the RS type, improved the cookie quality.

• 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'.

• Korean journal of food and cookery science
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• v.20 no.1
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• pp.42-48
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• 2004

The effect of xylitol on the Dongchimi fermentation was investigated by measuring the sensory, physicochemical and microbiological properties during fermentation of up to 30 days. Dongchimi with 0, 1, 2, 3 and 4％ w/v xylitol was fermented at 10$^{\circ}C$. The addition of 1％ xylitol gave the highest scores in terms of the overall acceptability, texture, ripeness, sweet taste and smell. During the fermentation, the total acidity increased, while the pH gradually decreased. The reducing sugars showed the highest content with the addition of 1％ xylitol. The vitamin C was increased in the early stage of fermentation, but reduced gradually after 5 days. The vitamin C content of the Dongchimi with 2％ xylitol addition was shown to be the highest. The total viable cells and lactic acid bacteria increased between 2 and 5 days of fermentation, but were gradually reduced thereafter. The numbers of lactic acid bacteria with 1％ xylitol addition were more numerous than with the other percentage additions. The current study showed that the application of 1％ xylitol to the fermentation of Dongchimi enhanced the sensory values of the fermented product.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.396-403
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• 2012

This study was conducted in order to investigate the effect of storage temperature abuse on the freshness of refrigerated and frozen spent hen's meat. After a room temperature storage condition, two different storage temperature were followed: refrigeration and frozen storage. All parts of the spent hen's meats were thawed at 4 d intervals up to 3 times (2, 6, and 10 d) for 24 h. The level of bacteria on the different parts of the refrigerated and frozen meats was higher than 6 Log CFU/g under the following storage conditions: refrigerated - breast, 12 h; leg, 6 h; wing, 12 h at the $1^{st}$ analysis, frozen - breast, 12 h at the $2^{nd}$ analysis; leg, 24 h at the $1^{st}$ analysis; wing, 12 h at the $1^{st}$ analysis. The pH value for the leg meat was higher than breast and wing meats. In the color measurements, under the room temperature storage condition, lightness and redness values decreased but the yellowness increased in refrigerated meats (p<0.05). The K-value regarding refrigerated leg meats exceeded 60%, which is the threshold value to evaluate the degree of freshness, during the $1^{st}$ analysis (p<0.05). The VBN value of refrigerated leg meat was the highest and reached up to 96.93 mg%. Thus, studies regarding the possible decline in quality according to the change of storage temperature could be used in order to establish a basic database for the quality control of spent hen meat being traded with other countries.