• Food Science and Preservation
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• v.21 no.1
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• pp.1-8
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• 2014

We prepared Jeotgal with Haliotis Discus Hannai Ino (abalone) viscera and the studied the physicochemical properties. Abalone viscus was fermented with varying amounts of salt for 60 days in order to prepare for the Jeotgal. During the fermentation, we measured the change of pH, volatile basic nitrogen (VBN), amino nitrogen (AN) and protease activity. After the fermentation, we examined the composition of free amino acids and sensory evaluation. The pH decreased with the fermentation, which was not significant (from 5.5 to 6.5). After the fermentation, the highest VBN was 96.7 mg/g, while the highest AN value was 406.3 mg/g. Unlike VBN and AN, the protease activity increased and reached the highest activity at the 30th day, and then decreased afterward. Based on the results, it was deduced that higher salinity restrained the fermentation and lowered the VBN, AN and protease activity. The total free amino acids of abalone Jeotgal, which were analyzed after the fermentation, (62.75 mg/g) was more than twice the amount in the abalone viscera before the fermentation (30.37 mg/g). We prepared abalone viscera Jeotgal and studied the characteristics for the first time. This will provide us with useful information for future related researches.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.393-398
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• 2000

To extend utilization of alginate from the sea tangle, Laminaria japonicus, depolymerized alginates (HAG-10, average molecular weight 10,000; HAC-50, average molecular weight 50,000; HAG-100, average molecular weight 100,000) were obtained by hydrolysis of alginate by heating at $12^{\circ}C$. The effects of each depolymerized alginate on excretion of cholesterol, glucose and namium in rats were investigated. The total excretion rate (${\%}$) of cholesterol and cadmium was the highest in rats administered with HAG-50, The rate was $45.81{\%} and 59.02{\%} with HAG-50$. It was high in the order of $45.78{\%} and 56.05{\%}$ in HAG-100, $41.28{\%}$ and $55.96{\%}$ in alginate, and $32.11{\%} and 44.92{\%} in HAC-10$, respectively. In the case of HAG-50, it significantly (p<0.01) prevented the serum glucose level of rats from rising within 30 min and 60 min after glucose loading or administration among all the samples, but it had no particular effects on the serum insulin level. In conclusion, it was suggested that HAG-50, in which the alginate had a decreased molecular weight, while still retaining its desirable functions as a dietary fiber, was effective in excretion of harmful substances, such as cadmium and cholesterol, and in lowering glucose activities in serum of rats.

• Food Science and Preservation
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• v.21 no.5
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• pp.652-660
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• 2014

To maintain the microbiological safety of Prunus mume fruit before it is processed, it was treated with a combination of 0.5% citric acid and 0.1% Tween 20, and stored at $4{\pm}1^{\circ}C$ for seven days. The combined treatment reduced total aerobic bacteria, yeast, and mold populations in the fruit by 2.20 and 1.70 log CFU/g, respectively, compared to those in the control. Organic acid contents and the Hunter $L^*$, $a^*$, and $b^*$ values were not affected by the treatment during the storage. In addition, the dried Prunus mume fruit prepared with 40% red algae extract (RAE) or maltodextrin (MD) treatment and hot-air drying were compared with respect to the fruit's physicochemical properties such as color, total phenolic and flavonoid content, and microstructure. The hot-air dried samples had undesirable color changes and inferior textures. The RAE-treated samples had a higher total phenolic content (225.15 mg gallic acid equivalent (GAE)/100 g) and total flavonoid content (49.25 mg quercetin equivalent (QE)/100 g) than the other treatments. The treatment of Prunus mume fruit with RAE can provide better-dried products than can MD treatment or hot-air drying. These results suggest that the combined treatment with citric acid and Tween 20 can be effective in preserving the microbiological safety of Prunus mume fruit, and its dehydration using RAE is an efficient drying method.

• Food Science and Preservation
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• v.20 no.3
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• pp.317-322
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• 2013

This study was conducted to investigate the effects of pretreatment and different packaging methods on the physicochemical properties of cold vacuum-dried peaches. All the dried peach samples were stored such as $N_2$ gas substitution, vacuum and passive packaged with polyethylene (PE) film and oriented polypropylene (OPP)/aluminum (Al)/PE film at $40^{\circ}C$ for 50 days. The weight change, pH, soluble solids content, titratable acidity, soluble solid-acid ratio (SS/TA), delta E, browning degree and phenolic compounds were analyzed. The weight change and pH were lower in the 0.1% vitamin C-treated group and were significantly lowest in the vacuum-treated OPP/AL/PE. The soluble solids content and the SS/TA were higher in the non-treated groups than in the vitamin C-treated groups. According to the packaging methods, the $L^*$ values were higher in the vacuum, $N_2$ gas and passive package, in that order. In addition, the browning degree and the delta E value were lower in the pretreated groups and significantly lowest in the vacuum-treated OPP/AL/PE with 0.1% vitamin C group. The phenolic compounds were high for the pretreated groups, according to the packaging methods (vacuum > $N_2$ gas> passive), and the OPP/AL/PE was significantly higher than the PE. These results suggest that different packaging materials and pretreatment methods affected the quality of the dried peaches, and the vacuum-OPP/AL/PE film packaging group showed a high quality.

• Food Science and Preservation
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• v.24 no.5
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• pp.576-584
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• 2017

With the goal of developing a new functional fermentation milk using green tea powder (GP), milk was fermented with direct vat set (DVS) starter culture containing Streptococcus salivarius subsp. thermophilus, Lactobacillus paracasei and L. delbrueckii subsp. bulgaricus. We investigated fermentation characteristics and antioxidative activities of fermented milk supplemented with different concentrations (0.5, 1, 2, 3%) of GP. All samples were evaluated for pH, total acidity, viable cell count, and sugar contents. The pH of all samples decreased during fermentation, and the final pH ranged from 4.35 to 4.51. The acidity increased during fermentation, after the fermentation was completed, the titratable acidity was 0.8 to 1.1%. And viable cell count of all samples increased during fermentation, and the final viable cell count was 8.57 to 8.89 log CFU/mL. The sugar content decreased as the fermentation proceeded and finally reached 12 to $13^{\circ}Brix$. And increasing GP, decreased brightness and increased yellowness. Increasing GP concentration added to milk, improved DPPH free radical scavenging activity and ferric ion reducing activity of fermentation milk. The fermentation milk kept their pH, total acidity and viable cell counts standard of fermentation milk during the storage period at $4^{\circ}C$. These findings confirmed the possibility of development of the novel functional fermentation milk through the investigation of the quality characteristics of the fermentation milk added with GP.

• Clean Technology
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• v.21 no.4
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• pp.271-277
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• 2015

A photocatalyst which mixed by the commercialized P25-TiO₂ and a synthesized Ag_xO was used in an appropriate weight ratio to effectively produce hydrogen gas in this study. The Ag_xOs were synthesized with the conventional sol-gel method, and tetramethylammonium hydroxides were added at the synthesis process in order to stabilize the solutions, and then the solutions were heat-treated at the temperatures of -5, 25, and 50 ℃, resulted to obtain the three types of silver oxides. Physicochemical properties of the synthesized Ag_xOs were identified through X-ray diffraction analysis (XRD), scanning emission microscopy (SEM), ultraviolet-visible spectroscopy, and X-ray photoelectron spectroscopy (XPS). In the photolysis results of water/methanol (weight ratio 1:1) solution, the mixture of P25-TiO₂/Ag_xO exhibited a significantly higher hydrogen gases evolution, compared to that of pure P25-TiO₂. Additionally, the addition of H₂O₂ as an supplement oxidant and in Ag_xO synthesized at 50 ℃ improved the hydrogen production efficiency. In particular, the emitted hydrogen gases reached to 13,000 μmol during 8 hours when a mixed catalyst, Ag_xO of 0.1 g and P25-TiO₂ of 0.9 g, were used.

• Clean Technology
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• v.18 no.2
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• pp.162-169
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• 2012

Pt-Sn/${\theta}-Al_2O_3$ catalyst for n-butane dehydrogenation reaction was prepared by incipient wetness method. To confirm the physicochemical properties of Pt-Sn/${\theta}-Al_2O_3$ catalyst, the characterization was performed using X-ray diffraction (XRD), $N_2$ sorption analysis, temperature programmed desorption of $NH_3$ ($NH_3$-TPD), temperature programmed reduction of $H_2$ ($H_2$-TPR) techniques. Also, the catalytic activities of Pt-Sn/${\theta}-Al_2O_3$ for n-butane dehydrogenation was tested as a function of pretreatment temperature, pretreatment time, reaction temperature, and the partial pressure of n-butane and hydrogen. The sum of selectivities to n-butenes consisting of 1-butene, cis-2-butene, and trans-2-butene was almost constant 95% in the range of conversion of n-butane 5-55%. The activation energy calculated from Arrhenius equation was $82.4kJ\;mol^{-1}$ and the reaction orders of n-butane and hydrogen from Power's law were 0.70 and -0.20, respectively.

• Journal of Life Science
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• v.23 no.7
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• pp.879-885
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• 2013

Baby powder is an astringent powder used to prevent diaper rash. It also has other cosmetic uses. In general, it is composed of talc powder (talcum powder). Talc powder is harmful if inhaled because it can cause significant lung damage. With the aim of developing a new rice-based baby powder, three kinds of rice varieties were selected and pulverized. To determine the cost-effectiveness of the different states of rice powder, several milling processes were tried, and the powder characteristics of the resulting rice powder, such as particle size, biological activities, digitalized color value, and moisture content before and after coating treatment with essential oil and silicon oil, were examined. "Goami" showed good flour characteristics with respect to lightness (92.0, $L^*$[D65] value) and particle size ($8.9{\mu}m$). SEM analysis showed that the rice powder particles coated in the essential oil and silicon oil showed a smoother and rounder appearance than those of the talc powder. In addition, the average particle size was decreased by the essential oil and silicon oil coating. The silicon oil coating solved the problem of moisture absorption in rice flour. Rice flour properly coated with essential oil and silicon oil shows great potential as a new material source of powder.

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.490-496
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• 2001

The purpose of this study was to investigate the effects of ingredients(spices and medicinal plants) on the physicochemical properties of Pyunyuk a Korean style-cooked pork. Pyunyuk samples were prepared by the following 5 cooking conditions: Control(pork, water), A(pork, water, soy sauce), B(pork, water, soy sauce, onion, ginger), C(pork, water, soy sauce, onion, ginger, licorice, cinnamon) and D(pork, water, soy sauce, onion, ginger, licorice, cinnamon, clove and chestunt inner skin(CIS). The contents of ash, crude protein in loin and shank Pyunyuk were not significantly different among Pyunyuk samples, but crude fat content of C, D were significantly lower than control, A and B(p＜0.05). In Hunter’s color values of Pyunyuk, the lightness(L) was decreased by the addition of multiple ingredients, whereas the redness was increased. In mechanical characteristics, the hardness of control was the highest among the samples(p ＜0.05). In sensory evaluation, sample D obtained the highest score in flavor, taste, hardness, cohesiveness, springiness, gumminess and overall acceptability(p<0.05), and it was most preferred by the panels. There were higher negative-correlations between mechanical hardness and sensory characteristics of flavor, taste, cohesiveness, gumminess, brittleness and overall acceptability. From these results, it could be concluded that Pyunyuk ingredients(herbs and medicinal plants) reduce the content of crude fat, increase the tenderness and improve the flavor and taste of pork during cooking.

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.464-471
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• 2001

Physicochemical and sensory properties of Kakdugi prepared with spring cultivars of radish were compared during fermentation. Among 5 cultivars,` ‘Bagkwang’‘Chunhadaehyung’and ‘Bakbong’ were heavier in average weight and longer in length than others. Sugar content and hardness were the highest in ‘91144’and ‘Bakbong’, while moisture content, in ‘Bagkwang’ and ‘Bakbong’, During fermentation at 20$\^{C}$ for 11 days, a great decrease in pH and great increase of acidity were observed in five Kakdugi samples after day 2. The acidity of ‘Bagkwang’ and ‘Housebommoo’ increased rapidly after day 2 until day 5 and then reached around 1.04-1.08% (lactic acid) at day 11, while those of ‘91144’ and ‘Bakbong’ increased slowly until day 5, but after day 7 increased rapidly up to 1.2-1.3%(lactic acid). ‘91144’ showed the highest ‘a’ value(redness), but ‘Bagkwang’, the lowest. Decrease in hardness during fermentation was the least in ‘Bakbong’, while ‘Chunhadaehyung’, the greatest. The result of sensory evaluation suggested that ‘Bakbong’and ‘Housebommoo’ were the best among spring cultivars of radish for Kakdugi preparation.