• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.454-458
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• 2002

The effect of antibrowning agents such as PVPP (polyvinylpolypyrrolidone), bentonite, gelatin, celite 545, tannic acid and sodium sulfite in apple concentrate was investigated for the control of enzymatic browning by comparing physicochemical properties (pH, color, turbidity), polyphenoloxidase activity and contents of polyphenol compounds. In color value, apple concentrate containing PVPP showed higher L value (lightness) than control and other antibrowning agents. The turbidity (absorbance at 660 nm) of apple concentrate added PVPP, gelatin celite 545, tannic acid and sodim sulfite were 0.003, 0.038, 0.018 and 0.022, respectively. PVPP was regarded to remove suspended solids effectively. Polyphenoloxidase activity and polyphenolics(catechol, catechin, chlorogenic acid, epicatechin) content of apple concentrate used PVPP significantly reduced. Therefore PVPP was proved to be effective for enzymatic antibrowning agent considering to color, turbidity, polyphenoloxidase activity and polyphenol compounds in apple concentrate.

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.31-39
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• 2003

The enzymatic isolation of residual lignins obtained from spruce and beech pulps (obtained by sulfite, kraft, ASAM and soda/AQ/MeOH pulping processes) and their characterization was described in previous publications. Here, the residual lignins have been submitted to potassium permanganate oxidation (KMnO₄ degradation), and 9 aromatic carboxylic acids (3 of them are dimeric) were identified after methylation with diazomethane by GC/MS. The analytical challenge during qantification by the internal standard methods was the partly high protein content of the samples, which resulted in elevated anisic acid yields in the degradation mixture of sulfite residual lignins. The results are compared with the KMnO₄ degradation of the corresponding MWLs and discussed in terms of S/G ratios and degrees of condensation. The latter was calculated as a quotient between the aromatic carboxylic acids derived from condensed and non-condensed lignin structures. Typical degradation patterns for the various processes have been observed. Among other parameter, the relative compositions between iso-hemipinic acid (which is for condensation in pos. 5 of the aromatic ring) and meta-hemipinic acid and 3,4,5-trimethoxyphthalic acid (both are for condensation in pos. 6 of the aromatic ring) was found to be process specific. Kraft and soda/AQ/MeOH residual lignins yielded higher amounts of iso-hemipinic acid. In contrast, the relative yields of meta-hemipinic acid and 3,4,5-trimethoxyphthalic acid (the latter in beech lignins) are higher in sulfite and particularly in ASAM residual lignin. In case of beech residual lignins the amount of acids originated from non-condensed syringyl type lignin units was surprisingly high. The condensation degree of residual lignins was shown to be generally higher than that of MWLs. This was especially true for the G units. ASAM residual lignin exhibited very high S/G ratios and degrees of polymerization. Causality between condensation degree and total yield of degradation products was demonstrated.

• Tuberculosis and Respiratory Diseases
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• v.39 no.2
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• pp.159-166
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• 1992

Background:Sulfiting agents are widely used as preservatives and antioxidants in foods, beverages and drugs including bronchodilators. There have been reports of sulfite-related reactions such as anaphylaxis, urticaria, angioedema, abdominal discomfortness as well as bronchospasm. Several investigators reported that sulfite-sensitive asthmatic patients comprised from 3.9% to 8.2% of all asthmatic patients and its prevalence was higher in steroid-dependent group than in steroid-independent group. Subjects and Method:We performed oral provocation test with sodium bisulfite and aspirin in 17 asthmatic patients who have experienced aggravation of their symptoms after administration of drugs or foods. All of them were steroid dependent asthmatics. We observed clinical symptoms and steroid requirements from 1 to 18 months. Result:Ten of them showed severe bronchoconstriction after the ingestion of sodium bisulfite (50 to 200 mg) within 30 minutes. Concurrent aspirin intolerance was noted by oral provocation test in four cases (40%). Three of them showed positive responses on skin prick test with sulfite (10 or 100 mg/ml). Mean total eosinophil counts was $844/mm^3$ at asthmatic attack. And there was no significant responses on skin prick test and IgE-RAST to common inhalant allergens. After complete avoidance from sulfite containing foods and drugs as well as antiasthmatic medication for 1 to 18 months, nine of them (90%) could stop or reduce the steroid requirements. ConcIusion:It was suggested that severe steroid dependent and intrinsic type of asthmatic patients should be evaluated for sulfite-sensitivity.

• Clean Technology
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• v.19 no.1
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• pp.59-64
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• 2013

Pt/carbon Electrode catalysts for PEMFC were synthesized using colloidal method. PSA (platinum sulfite acid) was used as a Pt precursor and CPA (chloroplatinic acid) was also used to replace relatively expensive PSA. Electrode catalysts prepared using PSA showed Pt particle size less than 3.5 nm and Pt yield higher than 90% in 10~40 wt% Pt loading. Electrode catalysts prepared using CPA also showed Pt particle size less than 4.4 nm and Pt yield higher than 80% in 10~40 wt% Pt loading. The MEA (membrane electrode assembly) using 20 wt% Pt/VXC72 showed equivalent I-V curve comparing with commercial electrode catalyst in single cell test.

• Journal of Korean Society of Forest Science
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• v.57 no.1
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• pp.14-19
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• 1982

Fines in high-yield sulfite pulp have much higher water retention value as compared with fines in Stone groundwood pulp. Therefore, they are apt to adhere partially or entirely onto the fiber surface during the paper making. This tendency is greatly enhance with decrease of the pretreated yield and increase of the water retention value of fines. Fines, which adhere onto the fiber surface in paper, contribute to the light scattering of the paper. Accordingly, the specific scattering coefficient of fines in high-yield sulfite pulp is considerably lower than that of fines in stone groundwood pulp, which hardly adhere onto the fiber surface. The fact that high-yield sulfite pulp is inferior to stone groundwood pulp in opacity is explained on the basis of the high degree of swelling of fined in addition to the softening of fiber fraction.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.4
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• pp.42-48
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• 2001

The spent liquor (BSL) obtained from alkaline sulfite-anthraquinone (AS-AQ) cooking of pine bark was applied as a deinking agent. In the ONP deinking system, although BSL removed the small size of ink particles (${\geq}$$12.5{\mu}m$), it did not improve the brightness of pulp. The brightness of pulp slightly improved when treated with BSL at 150~$180^{\circ}C$. However, the brightness of the pulp was lower than that of a commercial deinking agent (oleic acid). It seems that BSL treated with a high temperature still had a high dispersing ability on the ink particles. Intensive oxidations were introduced, and remarkable deinking effects were observed at 13kgf/$cm^2$ oxygen pressure, $160^{\circ}C$ and 2h. When BSL treated at 13kgf/$cm^2$ oxygen pressure, $170^{\circ}C$ and a time period of 30~90 min is added to the pulp, at 0.1% or lower, the deinking effect became higher than that of oleic acid. On the other hand, additional alkali treatments during the oxidation possibility as a deinking agent when oxidized. However, since the oxidized BSL still has a high dispersing ability and lower molecular weight, several modifications need to be done in the near future in order to be applied as a high quality deinking agent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.17-22
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• 1977

In the present paper, the effect of sodium sulfite treatment on tile inhibition of browning reactions occurring in the storage of dried oyster was tested and the supplementary effect of antioxidantsaddedwasalsomentioned. Dried oysters treated with sodium sulfite solutions as described in the previous paper(Lee and Choi, 1977) were stored in the bottles with silica gel bags at room temperature with or without the application of antioxidants. The ethanol solution of an antioxidant mixture(BHA, BHT, plus, synergists) was sprayed on the surface of cooked oyster before drying. The density of brown pigment was determined spectrophotometrically by measuring the absorbance at 420 and 440 nm of both fractions of pigment extract, namely chloroform-methanol and water soluble fractions, which represent the brown color developed by fat oxidation and Maillard reactions respectively. TBA value was also measured for the oxidative rancidity in oysters during the storage. It appeared from the results that the 0.5 M sodium sulfite-60minute treated samples showed better effect after 150 day storage at room temperature. Controlling tile pH of treating solutions, did not reveal so much different in inhibitory effect in the aspect of color but a more reduction of tyrosine and reducing sugar was resulted with acidic solution than with alkaline solution. The development of brown color in dried oyster seemed to be leaded rather by the oxidative rancidity of lipids than sugar-amino reactions particularly in a long-term storage since the browning of chloroform-methanol fraction progressed more rapidly than of water. soluble fraction. The application of antioxidant, therefore, could largely retard the browning of the product as appeared in the results that sodium sulfite treated oyster with addition of antioxidant kept the best color during the storage.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.974-979
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• 2000

A total of 80 weaned piglets (Landrace $\times$ Yorkshire $\times$ Large White) were used in a 28-day growth assay to detennine the optimal inclusion level of sodium sulfite ($Na_{2}SO_{3}$) as an extrusion enhancer of soybean meal for nursery piglets. piglets (21 d of age, 6.04 kg of BW) were grouped into 4 treatments in a completely randomized block design. Treatments were: 1) Extruded SBM (Control), 2) Extruded SBM with 0.5% $Na_{2}SO_{3}$ (0.5 ESBM), 3) Extruded SBM with 1.0% $Na_{2}SO_{3}$ (1.0 ESBM) and 4) Extruded SBM with 1.5% $Na_{2}SO_{3}$ (1.5 ESBM). Each treatment has 4 replicates of 5 heads per pen. In phase I (d 0 to 14), diets supplied 3,400 kcal ME/kg, 23% crude protein, 1.65% lysine, 0.50% methionine, 0.9% Ca and 0.8% P. Phase II (d 14 to 28) diets contained 3,300 kcal ME/kg, 21% crude protein, 1.45% lysine, 0.45% methionine, 0.9% Ca and 0.8% P. For d 0 to 14, piglets fed 1.5 ESBM had greater ADG, ADFI and FCR compared to piglets fed control and 0.5 ESBM diet. ADG was significantly higher in piglets fed 1.5 ESBM diet than other groups (p<0.05) except 1.0 ESBM. In phase II (d 14 to 28), there was no significant differences in production traits among treatments. For overall period (d 0 to 28), piglets fed diets with high sodium sulfite grew faster than piglets fed control and 0.5 ESBM diets. The highest ADG and the best FeR were obtained in piglets fed diets with 1.5 ESBM during the entire period. Piglets fed 1.5 ESBM diet showed significantly higher crude protein digestibility than 0.5 ESBM (p<0.05) at d 14 post-weanling, but not at d 28 post-weanling. There were no significant differences in digestibilities of total amino acids. In conclusion, the addition level of 1~1.5% sodium sulfite for SBM extrusion could be favorable for rate and efficiency of growth in weaning pigs.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.218-223
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• 1989

This study was performed to investigate the natural contents of sulfite in vegetables and fruits. Experimental subjects included 351 cases of vegetables and 59 fruits collected in 4 areas-Jeonbuk, Kyungnam, Chungcheung and Kangwon-from October to December in 1987. Sulfite of the subjects were determined by ion chromatography rapidly and precisely. Mean value of sulfite contents in leaf-vegetables, green onion was the highest value, $13.23{\pm}1.39\;ppm$. Garlic was the highest value, $134.07{\pm}9.65\;ppm$ in root-vegetables. Green pepper in fruit-vegetables was the highest value, 1. $1.16{\pm}0.12\;ppm$. In the fruits, persimmon was the highest, $2.74{\pm}0.45\;ppm$. There were some differences among the areas. The mean value of sulfite contents in vegetables and fruits collected in the Chungcheung areas were higher than that in other places.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.747-750
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• 1998

The application of spent liquor(BSL) obtained from alkaline sulfite-anthraquinone cooking of pine bark to cement mortar significantly improved the water-reducing ability and decreased the rate of cement hardening. However, the compressive and flexural strength of BSL addition to cement mortar were lower than that of PLAIN. The application of 0.2% antifoamer to BSL slightly decreased water-reducing ability, but remarkably improved the compressive and flexural strength of cement mortar. On the other hand, BSL decreased the rate of hardening of cement, which exhibited the protperties of the lignosulfonated based retarding water-reducing type. but the setting time of cement could be controlled by addition of Na2CO3 could be used to convert BSL to normal or accelerating concrete admixtures.