• Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.145-157
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• 2023

Surimi has been traditionally used as the main ingredient in gelling foods, such as imitation crab sticks. However, it can also be used to manufacture snacks without gelling properties. To assess the properties of surimi as a snack ingredient, we prepared fried fish snacks with different surimi grades of Alaska pollack (AP) and threadfin bream (TB) and evaluated their quality characteristics. AP had significantly higher protein and gel strength values than TB did. Regarding color, TB showed significantly lower lightness (L) values and higher redness (a) and yellowness (b) values than AP did, consistent with the appearance of a brown color. TB had significantly lower hardness values, higher thickness expansion, and higher oil content than AP did. Hardness was found to be positively correlated with gel strength and negatively correlated with oil content. In the micro-structure images, more blistering was formed in TB, indicating higher expansion and crispiness. In the sensory evaluation, TB showed higher overall sensory acceptance than AP did, which is the result of its high color content, crispiness, taste, and aroma. Principal component analysis of the electronic nose and tongue revealed that the samples were clearly separated. In particular, TB had more aromatic components than AP in the electronic tongue. Our findings indicate that gel strength, which determines the quality properties of surimi, does not need to be considered in snack manufacturing. In fact, surimi with low gel strength is a more suitable ingredient for snack manufacturing.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.899-910
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• 2021

This study was performed to suggest concentration methods leading to the production ofhoney with an excellent flavor by examining the effects of the concentration temperature and method on changes in 5-hydroxymethyl-2-furaldehyde (5-HMF) levels and the flavor components of honey. The 5-HMF contents of honey samples concentrated in a tray concentrator at 45, 50, 60, and 70℃ were 2.1, 2.3, 2.5, and 3.1 mg·kg^-1, respectively, demonstrating that the 5-HMF contents increased as the concentration temperatures were increased. The honey vacuum-concentrated at 70℃ showed a higher 5-HMF content than that at 60℃, similar to the tray-concentrated honey at different temperatures. The main and other minor flavor components of the honey were volatilized and significantly reduced after vacuum concentration. In the tray concentration, all of the honey samples concentrated at 40, 50, 60, and 70℃ showed flavor component patterns similar to each other, and most of the main and other minor flavor components in the honey were volatilized and significantly reduced after tray concentration. As such, most of the main and other minor flavor components of the honey were mostly removed at 70℃ after both the vacuum concentration and tray concentration processes. The effects of the concentration method and temperature on the viscosity, 5-HMF level, and flavor components of the honey were found to be significant in this study. Given that the components of honey were shown to undergo significant physicochemical changes depending on the concentration method used and temperature during laboratory-scale production, the concentration methods devised in this study can be applied industrially.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.3
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• pp.231-240
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• 2020

This research was conducted to evaluate the physicochemical properties, antioxidant components, and their activities for more taking advantage of small redbean cultivars. Seed size, 100 seeds weight, and hardness on the 8 cultivars were measured. The free sugar and crude protein contents were evaluated using HPLC and protein analyzer, respectively. Amylose content, antioxidant components, and activities were analyzed by spectrophotometer. The range of 100 seeds weight and hardness were 12.55-18.81 g and 9,527.38-14,341.25 gf, respectively. Total free sugar, amylose, and crude protein were showed 22.49-31.07 mg/g, 13.53-15.67%, and 21.27-23.30%, respectively. The cultivar 'Hongeon' was higher antioxidant component and activity more than others. In clustering the cultivars based on the results, the tree showed four major clades. The 'Huinnarae' group was high in total free sugar and amylose content. The 'Hongeon' group were high in 100 seeds weight, antioxidant component. and activity, while amylose content was lower than that in the other groups. The results of the cultivars can be utilized for research of functional materials. The findings of this study will provide valuable information for expansion of functional food industry related on small redbean.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.427-434
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• 2008

Processing of collagen from yellowfin tuna (Thunnus albacares) abdominal skins was optimized by response surface methodology and central composite design. The values of independent variables at optimal conditions were NaOH concentration: 0.5 N, NaOH treatment time: 36.2 hr, pepsin concentration: 1:4.9 ratio (0.245%, w/v), and digestion time: 48.1 hr, respectively. The collagen content estimated under optimal conditions was 33.1%, and the actual experimental collagen content was 32.3%. Physicochemical properties of collagen from yellowfin tuna abdominal skin were investigated by amino acids analysis, SDS-PAGE, FT-IR, viscosity and denaturation temperature. Amino acids content of the collagen was 21.0%. SDS-PAGE pattern of the collagen showed two different $\alpha$-chain (${\alpha}_1$- and ${\alpha}_2$- chain), $\beta$-component and $\gamma$-component. The spectrum of FT-IR of the collagen showed wavenumber at 3,434, 1,650, 1,542 and $1,235\;cm^{-1}$ representing the regions of amide A, I, II and III, respectively. Relative viscosity of the collagen decreased continuously on heating up to $32^{\circ}C$, and the rate of decrease was retarded in the temperature range of $35-50^{\circ}C$. Denaturation temperature (Td) of the collagen solution (0.06%, w/v) was $31^{\circ}C$ and was lower than calf skin collagen ($35^{\circ}C$).

• Korean journal of food and cookery science
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• v.20 no.3
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• pp.279-286
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• 2004

The physicochemical and sensory qualities of pumpkin jams, in which sucrose was replaced with oligosaccharides, were investigated during storage at 20$^{\circ}C$. pumpkin jam was prepared with steamed grind pumpkin, mixed with either sucrose only(50％), corn syrup(COS, sucrose 30％＋COS 20％), fructooligosaccharide (FTO, sucrose 30％＋FTO 20％), isomaltooligo saccharide (IMO, sucrose 30％＋IMO 20％), or galactooligo-saccharide(GTO, sucrose 30％＋GTO 20％). The final sweetness of each pumpkin jam was 64$^{\circ}$ Brix. During 60days of storage there were no differences in acidity and pH among the treatments. Reducing sugar content was higher in the pumpkin jam containing COS compared to 次e others. During storage Lightness(Hunter L), redness(a value) and yellowness(b value) increased, of which L and b values were the highest in COS, and the a value were higher in sucrose compared to the other sugars. Adhesiveness and hardness of textural properties were the highest in sucrose. Sensory evaluation results showed that the mean scores of over-all acceptability during storage did not significantly decrease until the 30th day of storage, compared to the freshly made jams. Physicochemical and sensory characteristics of pumpkin jams during storage in a PCA plot were comprised of the first principal component (99.44％) and the second principal component (0.54％).

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.60-68
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• 1993

It has been known that the silk degumming treated by hot alkali solution is easy to handle but is liable to yield poor-quality silk due to the degree of degumming loss, incomplete-degumming or over-degumming. Therefore, many studies have been carried out on the silk degumming by enzyme in order to improve the quality of silk. However, no attention has been paid to the physicochemical analysis of enzymatic degummed silk. In this paper, two different degumming methods, soap and enzymatic, are compared in aqueous solution state of silk fibroin. The results can be summarized as follows: There was no significant difference between two solutions on the bases of polarizing microscopy, TEM observation and SDS-PAGE. Spherulite of silk fibroin was not observed in polarizing microscopy, however the leaf-shape fibril structure was developed upon solidification. The size of spherulites of silk fibroin in TEM observation were 30~120nm with a wide range of size distribution. The intrinsic viscosity of enzymatic degummed fibroin solution was lower than that of soap degummed solution. This can be explained that the silk fibroin was more degraded by enzymatic degumming method compared with the soap degumming method. SDS-polyacrylamide gel electrophoresis showed that the fibroin molecule was composed of large component of molecule weight above 50 kd and small component of molecule weight about 20 kd. There was no difference in crystallinity between two degumming methods on the bases of results of DSC thermograms and IR spectra.

• Journal of Conservation Science
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• v.37 no.1
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• pp.63-76
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• 2021

The purpose of this study is to scientifically analyze physicochemical characteristics of the roof tiles used for palaces in the Joseon Dynasty which stored in Changdeokgung material storage and Seooreung Jaesil and the modern handmade ones which made by N company to understand the differences between their manufacturing techniques. Through chromaticity, cross-sectional observation, component analysis, and crystal structure analysis, it was possible to confirm the physicochemical properties and fired properties of the roof tile. Roof tiles from the Joseon Dynasty have a wider colorimetric range and higher apparent porosity and water absorption, on average, than the modern roof tiles. The cross section of the Joseon Dynasty roof tiles shows that most clay minerals have not been vitrified, remaining in the form of atypical particles, while the modern roof tiles have denser clay materials. X-ray diffraction analysis identified low-temperature minerals such as micas in Joseon roof tiles but no peak of these minerals was observed in the modern roof tiles, implying that the modern ones are fired at higher temperature than the Joseon ones. Therefore, the modern roof tiles are fired at higher temperature and have higher density than the Joseon ones due to the use of pugmills. The general content of main ingredients was similar between the two. Additionally, the principal component analysis of trace elements in the Joseon roof tiles showed that most samples were from similar areas. It seems that the Joseon roof tiles were manufactured using soils supplied from a specific region at the same timeframe and their consistency in the content of principal components implies that they also have similar mix proportions of clay.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.108-114
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• 2002

Cellular glass foam (CGE), the reprocessed glass, has a possibility as a component of vegetative propagation media of floricultural crops due to the its excellent air and water permeability, similar to that of perlite. An experiment was conducted to evaluate the rooting and growth thereafter of Kalanchoe blossfeldiana ‘Gold Strike’in media containing various volume ratios of granular rockwool, peat-moss, CGF and perlite. The particle size of CGF and perlite was 2.0~4.0mm and 1.2~4.0mm, respectively. Cuttings were rooted in a fog tunnel with a mean temperature of 18.2$^{\circ}C$ and RH of 66.7％ under a long day regime (14 h per day light period). Height, length of the longest root, stem diameter, no. of leaves, leaf area, percentage of rooted cuttings, shoot and root fresh weights, shoot and root dry weights, total chlorophyll concentration and physicochemical properties were measured. Cuttings rooted 100% in all treatments. Physicochemical properties in CGF and perlite-containing media showed little differences. The growth of rooted plants in the CGF-containing media was similar or rather superior to that in perlite-containing media. Consequently, CGF has a possibility as a vegetative propagation medium of Kalanchoe. To make wider commercial use of CGF, more demonstrative experiments and analyses are necessary.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.309-314
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• 2007

The physicochemical and sensory characteristics of rice wine, Yakju, made with different additions of red yeast rice (0, 10, 20, 30, and 40%) were investigated. The pH of the rice wine decreased and the total acidity increased with greater additions of red yeast rice. Furthermore, the total sugar content increased and the alcohol content decreased with increasing amounts of red yeast rice. The color L-value diminished and the color a- and b-values increased with increasing amounts of red yeast rice. Among the volatile flavor compounds, esters, aldehydes, alcohols, and acids were the most important aroma-active compounds identified in the rice wine. The sample with the 10% red yeast rice addition had the highest ester content, which is a primary component in fruit fragrance. The highest overall acceptability values in the sensory test for color, flavor, taste, and overall favorite were 5.10, 5.75, 5.15, 4.65, and 4.50, respectively, with the addition of 10% red yeast rice.

• Food Science and Preservation
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• v.12 no.5
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• pp.442-448
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• 2005

To develop efficient drying method, one of important process in manufacturing of Saengsik, uncooked food, the change of physicochemical characteristics and functional component contents of cereals dried by various drying methods was investigated. The proximate composition and dietary fiber content of rice, brown rice, glutinous rice and barley showed little changes during hot-air drying (50$\circC$, 55$\circC$, 60$\circC$) and freeze-drying. Yellowness(b) value of hot-air dried products was higher than one of freeze-dried products. The content of niacin was 0.77 mg% in milled rice, 1.84 mg% in brown rice, 0.68 mg% in glutinous rice, 1.00 mg% in barely dried by hot-air at 60$\circC$ and was lower than those of other samples. $\beta$-glucan content in barely was not changed by hot-air drying and freeze-drying method. In conclusion, hot-air drying would be recommended for barley having $\beta$-glucan, a kind of functional components and freeze-drying should be used for raw materials having heat-labile components such as niacin.