• Progress in Superconductivity
• /
• v.13 no.2
• /
• pp.133-138
• /
• 2011

To reduce the processing cost of the single grain REBCO (RE: Rare-earth elements) bulk superconductors, a cost-effective process should be developed. One possible way of developing the cost-effective process is the use of low-cost precursor powders. In this study, the single grain YBCO superconductors were fabricated using a home made powder. $YBa_2Cu_3O_{7-y}$ (Y123) powders were synthesized at $850-900^{\circ}C$ in air by the powder calcination method with repeated crushing and heat treatment steps. The processing parameters for the fabrication of single grain Y123 bulk superconductors, $T_{max}$ (maximum temperature), $T_p$ (peritectic temperature) and a cooling rate through $T_p$ were optimized. To enhance the flux pinning capacity of the single grain Y123 samples, $Y_2BaCuO_5$ (Y211) particles were dispersed in the Y123 matrix by adding $Y_2O_3$ powder to the calcined Y123 powder. Applying the optimized processing condition, the single grain Y123 superconductors with $T_c=91\;K$ and $J_c=1.5{\times}10^4\;A/cm^2$ at 2 T were successfully fabricated using a home made powder. The levitation forces and trapped magnetic field at 77 K measured using a Nd-B-Fe permanent magnet of 5300 G were 47 N and 3000 G, respectively, which are comparable to those obtained for the samples fabricated using a commercial grade Y123 powders.

• Korean Journal of Food Science and Technology
• /
• v.50 no.5
• /
• pp.504-510
• /
• 2018

Different processing methods, including steeping, boiling, roasting, and pressure roasting were used to deactivate anti-nutritional factors and remove off-flavor present in legumes. The physical and textural characteristic of cookie made with the treated flours were examined. The lightness of roasted cowpea flour was higher than that of the other treated legume flours, whereas that of pressure-roasted mungbean flour was the lowest. The boiled and pressure-roasted legume flours exhibited substantially lower pasting viscosity since the starches in these flours were considerably gelatinized during the heat treatment. Steeped mungbean flour had a significantly higher final viscosity than the other treated legume flours. Cookies containing mungbean flour had a higher protein content but lower lipid content than those containing cowpea flour. Cookies made with cowpea flour had a greater hardness than those made with mungbean flour. Cookies containing roasted flour had relatively better color properties than did those containing flours that were treated using other methods.

• Preventive Nutrition and Food Science
• /
• v.11 no.4
• /
• pp.311-317
• /
• 2006

Phenolic compounds in safflower seeds were recently found to stimulate bone formation and increase plasma HDL cholesterol levels in estrogen deficient rats, and to inhibit melanin synthesis. Nine phenolic compounds: $N-feruloylserotonin-5-O-{\beta}-D-glucoside,\;8'-hydroxyarctigenin-4'-O-{\beta}-D-glucoside,\;luteolin-7-O-{\beta}-D-glucoside$, N-(p-coumaroyl)serotonin, N-feruloylserotonin, 8'-hydroxy arctigenin (HAG), luteolin (LT), $acacetin-7-O-{\beta}-D-glucuronide$ (ATG) and acacetin (AT), were quantified by HPLC in safflower (Carthamus tinctorius L.) seeds during growth and processing. During growth, levels of the nine phenolic compounds in the seeds increased progressively with increasing growth stages, reached a maximum on July 30 (42nd day after flowering), and then remained relatively constant. During the roasting process, levels of phenolic compounds, except HAG, LT and AT, generally decreased with increased roasting temperature and time, whereas those of HAG, LT and AT increased progressively with increased roasting temperature and time. During the steaming process, levels of other phenolic compounds except HAG and AT generally tended to increase with increased steaming time, whereas those of HAG and AT were scarcely changed. During the microwave treatment, quantitative changes of phenolic compounds were similar to the roasting process, although there were some differences in levels of phenolic compounds between two heat treatments. These results suggest that the steamed safflower seeds after harvesting on late July may be useful as potential dietary supplement source of phenolic compounds for prevention of several pathological disorders, such as atherosclerosis and osteoporosis and aging.

• Preventive Nutrition and Food Science
• /
• v.10 no.4
• /
• pp.333-339
• /
• 2005

Three lactobacillus strains, two from infant feces, and one from cow's milk, were selected among 172 isolates, from multiple sources, for further study based on the antimicrobial activities against six strains of pathogenic bacteria and identified as Lactobacillus acidophilus. The strains revealed a wide scope of spectrum against pathogenic bacteria. Viable Lactobacillus acidophilus KH-l cell counts at pH 2.0 were slightly decreased to $1.42\times10^7$ CFU/mL from $4.18\times10^7$ CFU/mL, while remaining at $3.42\times10^7$ CFU/mL at pH 4.0 with the survival rate of $33.97\%\;and\;81.82\%$, respectively. At the concentration of $0.1\%$ oxgall, L acidophilus KH-l kept growing up to $3.12\times10^7$ CFU/mL with a mean growth rate constant (k) of 0.25, and cell number was slightly decreased to $1.21\times10^7$ CFU/mL (k=0.19) with $0.3\%$ oxgall, but remained at $7.6\times10^6$ CFU/mL (k=0.17) with $0.5\%$ oxgall. L. acidophilus KH-l had a $D_{60}$ value of 7.14, with viable cell numbers $1.4\times10^5$ CFU/mL after heat treatment at $60^{\circ}C$ for 30 minutes. Stability of L acidophilus KH-l at $-20^{\circ}C$ was significantly higher, when the strain was cultivated under the optimum growth temperature $(54.41\%\;and\;54.35\%)$ than at the temperature $(13.53\%)$.

• Korean Journal of Food Science and Technology
• /
• v.44 no.3
• /
• pp.269-273
• /
• 2012

The principal objective of this study was to estimate the benzo(a)pyrene contents in commercial vegetable oils available in the Korean market and to assess the effects of various processing steps for vegetable oils on the contents of benzo(a)pyrene. Benzo(a)pyrene content in the studied commercial vegetable oils, crude oils, and raw materials were found to be lower than the maximum levels of 2 ppb. In both refined and pressed oil, the benzo(a)pyrene contents can be reduced through refining steps. However, an evident increase of benzo(a)pyrene contents during both the expeller process for corn oil and the roasting process for sesame oil was observed. This result indicates that the processing procedure, particularly heat treatment and refining steps would be critical in managing the benzo(a)pyrene contents in vegetable oils.

• Journal of the Korean Applied Science and Technology
• /
• v.31 no.3
• /
• pp.534-540
• /
• 2014

The analysis of the change in the herbal tea composition according to the difference in processing conditions result. Was slightly reduced crude is treated ash puffing process was relatively increased, moisture, crude protein, the solid elution rate than the roasting process. Benzopyrene content was significantly reduced to 0.18 ppb from 0.35 ppb. Generation of food $B({\alpha})P$ is mainly include the thermal decomposition of food cooking, when the processing which is a main component of food carbohydrate, protein, fat reason despite severe heat treatment as a whole is to be detected even though the $B({\alpha})P$ in this way is considered to be. Generally the taste, aroma and color did not show a big difference but tasted quite stuffy and the strong sour taste reduced its preference.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.33 no.1
• /
• pp.15-21
• /
• 2023

To prepare zinc oxide powder, three types of sodium-based alkali precipitants such as NaOH, Na₂CO₃, NaOH/NaHCO₃ were compared to the differences in the manufacturing process of zinc oxide powder from zinc precipitate products like intermediates with the consideration of thermodynamic reaction. The prepared zinc precipitate products by the reaction with the sodium-based alkali precipitant were confirmed to respectively hydroxy zinc chloride (Zn₅(OH)₈Cl₂·H₂O) and zinc carbonate hydroxide (Zn₅(OH)₆(CO₃)₂·H₂O) from XRD analysis. Zinc oxide particles were compared in heat treatment at 800℃ according to sodium-based alkali precipitants. The mixed NaOH and NaHCO₃ of alkali precipitant reaction was contributed to synthesize the more uniform zinc oxide particles.

• Food Science and Preservation
• /
• v.24 no.5
• /
• pp.585-592
• /
• 2017

The purpose of this study was to prepare blueberry syrup (cheung) using fructooligosaccharide instead of the traditionally used sucrose. The sugar content, pH, and colorimetric values were measured to evaluate the quality of the prepared syrup, and the antioxidant activity and phenolic compound content were determined to assess the physiological activity of the syrup. The $L^{\ast}$ value (lightness), pH, and color were high in syrups containing a high proportion of fructooligosaccharide. The $a^{\ast}$ value (redness) was high in syrups subjected to heat treatment, and the $b^{\ast}$ value (yellowness) tended to be the opposite of the $L^{\ast}$ value. Moreover, syrups containing heat-treated fructooligosaccharide showed higher polyphenol, flavonoid, and anthocyanin contents than the unheated syrups did. The antioxidant activity of the blueberry cheung depended on the content of phenolic compounds. The highest value was obtained in the cheung prepared using a heat-treated 1:1 mixture of blended raw blueberry and fructooligosaccharide (S2). These findings suggest that our familiarity with the taste of the sweetener used influences our taste preference. It is therefore necessary to study other newly developed sweeteners apart from fructooligosaccharide to find a suitable alternative to sucrose.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.6
• /
• pp.1007-1016
• /
• 2023

In this study, the effect of functional substances such as polyphenols and flavonoids contained in large quantities in red ginseng and herbal medicines on the antioxidant activity properties and flavor effect were investigated by increasing the content and activity of functional ingredients by convert red ginseng through a steaming heat-drying process compared to the traditional dry processing method of ginseng and herbal medicines. According to the experimental results, the addition of pre-heat treatment significantly increased antioxidant properties such as DPPH radical scavenging ability, polyphenols, and flavonoids. In addition, during the steaming and heat-dried red ginseng manufacturing process, the amino-carbonyl browning reaction was promoted, resulting in increased brownness and a savory flavor. However, the content of ginsenosides, the main medicinal ingredient in red ginseng, became the main cause of the bitter and harsh taste. In addition, the bitter and harsh taste of red ginseng has been significantly improved by roasting and producing powder, but on the other hand, Radix Angelicae sinensis, polymorphic angelica and Peony, which are used as main medicinal ingredients in oriental medicine for nutritional tonic prescriptions such as 10 herbal medicine and 4 herbal medicine have a very strong herbal medicine-specific flavor and have a bitter and harsh taste. It is so strong that in order to use it as an instant extraction material, it was reviewed that a steaming and heating manufacturing method was needed during the manufacturing process.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.6
• /
• pp.889-893
• /
• 2016

This study was carried out to investigate the physicochemical and fermentation properties of yogurt made from high pressure processing (HPP) treated milk. Raw milk and commercial yogurt starter were used to make yogurt. Raw milk was HPP treated at 350 or 450 MPa (HPP 350 or 450) for 15 min or heat treated at $80^{\circ}C$ for 10 min. The numbers of lactic acid bacteria of the HPP treated group (HPP yogurt) rapidly increased during 2~4 h, whereas there was not significant difference from control (P<0.05). Titratable acidity of all samples increased, and pH decreased during storage from 0.99 to 1.24%, as well as from 4.59 to 4.20, respectively. It is confirmed that these values are in general ranges for yogurt. Control showed higher viscosity than HPP 350. Syneresis was significantly lower than that of the control (P<0.05). Based on the data obtained from the present study, HPP treatment was effective to enhance the quality of yogurt.