• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.339-346
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• 2020

Although aronia (Aronia melanocarpa (Michx.) Elliott) contains higher levels of polyphenols and more antioxidant activity than other berries, it is a berry that is difficult to eat raw due to its strong astringent taste and lack of sweetness. Therefore, in this study, we investigated the effect of tannin reduction of aronia by bioconversion method using mushroom mycelia cultures. Aronia and liquid cultures of Lentinula edodes and Phellinus linteus mycelia were mixed and then treated for 48 hours at 60℃. Tannin content, total polyphenol, total flavonoid and antioxidant activities (DPPH, ABTS radical-scavenging activities and FRAP activities) were investigated. The tannin content decreased from 64.2 mg ECE/g to 57.9 mg ECE/g (9.8% reduction) when treated with liquid culture of L. edodes and from 77.3 mg ECE/g to 47.9 mg ECE/g (38.1% reduction) from treatment with a liquid culture of P. linteus. Therefore treatment with mushroom mycelia culture solution may improve the palatability of aronia reducing the astringent taste.

• Nutritional Sciences
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• v.2 no.2
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• pp.65-70
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• 1999

Feeding rats a diet containing bean-hull causes hypertropy in their parotid glands due to the high tannin content. The amount of feedintake of rats led bean-hull was higher than that of rats fed a standard diet. However, the increase in body weight of rats fed bean-hull was lower than that of rats fed a standard diet, which resulted in significantly low feed efficiency of the bean-hull containing diet. Within one week, parotid glands significantly enlarged and a series of proline-rich proteins (PRPs) were produced, which were similar to those induced by feeding high-tannin sorghum with flight differences in molecular weights. Even though the direct comparison between PRPs produced by the bean-hull containing diet and those induced by the high sorghum diet is not appropriate due to laboratory inconsistences, several new PRPs were produced by high tannin diets in both experiments. Differences in molecular weights of PRPs induced in two different tannin sources must be funker investigated to be fully characterized. These morphological and biochemical changes have now been demonstrated to occur in response to the ingestion of tannins, presumably to diminish the anti-nutritional effects of tannins.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.95-101
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• 1999

This study was carried out to prepare green teas by traditional roasting manufacturing process, Ku Geung Ku Po and to determine the quality charateristics of the green teas by examining the change of their main components induced during this roasting process. The content of total sugars in unroasted tea leaves was 7.82%. Its content of roasted teas was decreased by increasing the number of roasting and there was significantly differences between samples. The content of total sugars in 9th roasted green tea was 3.98%. The total nitrogen contents of green teas produced by this process were 4.96∼6.38%. The more the number of roasting and the less content of tannin in green teas. And the ratio of total nitrogen and tannin in tea leaves 21.97 but its ratio in 9th roasted tea was increased to 45.54. The ascorbic acid in tea leaves consisted in 1,820.3 mg/100g but its content was decreased by increasing the number of roasting process. Whereas the content of caffeine in green teas was not reduced significantly by this traditional method. Of all amino acids, green tea produced by Ku Jeung Ku Po was rich glutamic acid, lysine and aspartic acid. And especially, phenylalanine, which was rarely found in other green teas, was abundant in these green teas. The compositions of glutamic acid and methionine were increased as increasing the number of roasting process but those of aspartic acid and arginine decreased by these processing. The main fatty acids of Ku Jeung Ku Po green tea were linolenic acid, linoleic acid and palmitic acid and the contents of unsaturated fatty acid in green teas were composed over 70% of total fatty acid. And the fatty acid contents in green teas were not affected during Ku Jeung Ku Po's process. The contents of minerals in these teas was rich in the oder of potassuim. magnessuim and calciumim, and these contents were not observed the prominant change during the process.

• Korean journal of food and cookery science
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• v.11 no.2
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• pp.158-163
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• 1995

This study was surveyed and compiled the contribution about acorn in korea .the physico-chemical properties of acorn and acorn starch. preparation of acorn starch and elimination of the acorn tannin, the rheological properties of acorn starch gel. Nutrition of acorn and antioxidative activity of tannin in acorn extract. The result obtained were as follow. 1. The chemical compositions of acorn were water 6.5∼13.7%, crude ash 1.9∼3.4%, crude fat 1.1∼5.0%, crude protein 5.8∼7.8%, crude fiber 2.1∼3.6%, N-free extract 71∼77.5%, total tannin 4.6∼9.3%, Ca 92.7∼460.9mg%, p 80.0∼740.9mg%, Na 66.2∼93.9 mg%, and K 867.9∼983.1mg%. 2. The acorn tannin was extracted with water, acetone, and ethanol. The generation method was wash SE settling method with water. 3. The shape of acorn starch granule was rounded triangular and some elliptical, rasing power 12.4∼12.5, Blue value 0.43∼0.47, Alkali number 10.8∼11.3, Amount of Arnylose 28.8∼30.50% Tannin contents on the initial go tim-zation temperature of acorn starch were not influenced but maximum and cooling viscosity o the acorn starch were decreased. 4. Nutritional effect and diet absorption rate were not influence, by rice and 20% T-A(elimination of tannin from the acorn) mixed diet, and the content of lipid in s rum were not influenced by rice 40% and T-A (elimination of tannin from the acorn) mixed diet. 5. jallic acid, digallic acid, gallotannin were contained in acorn powder extract. The main antioxidative : stlvity was speculated due to the gallic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.810-815
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• 1999

The pectinase treatment conditions for clarification of persimmon vinegar were optimized and monitored by response surface methodology. In clarification of persimmon vinegar by pectinase treatment with variations in temperature, time and concentration, coefficients of determinations(R2) of the models were above 0.91(p<0.05) in turbidity, browning color intensity and tannin content. The turbidity of persimmon vinegar was decreased along with an increase of pectinase treatment temperature. The minimum value of turbidity by pectinase treatment was 0.0021(absorbance at 660nm) in 49.38oC of pectinase treatment temperature, 73.08min of pectinase treatment time and 55.57ppm of pectinase concentration. The minimum value of browning color intensity by pectinase treatment was 0.27(absorbance at 660nm) in 48.39oC, 71.74min and 65.69ppm. The minimum value of total tannin contents by pectinase treatment was 43.72mg/100 ml in 40.05oC, 66.02min and 65.26ppm. The optimum conditions of pectinase treatment that satisfies the least common multiple of turbidity, browning color and tannin content were 40~50oC, 60~70min and 55~70ppm.

• Journal of the Korean Wood Science and Technology
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• v.51 no.2
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• pp.81-97
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• 2023

The aim of this study were to evaluate tannin resorcinol formaldehyde (TRF) for the preparation of cross-laminated timbers (CLTs) made from fast-growing tree species and to analyze the physical and mechanical properties of CLTs. TRF copolymer resin was prepared by using the bark extracts of Swietenia mahagoni (L.) Jacq. It was observed that the TRF adhesive possessed less solid content (23.59%), high viscosity (11.35 poise), and high pH values (10.0) compared to the standard phenol resorcinol formaldehyde. The TRF adhesive was applied to produce CLTs with the addition of 15% tapioca and flour as an extender. The six-layered CLTs were produced from sengon (Falcataria moluccana Miq.), jabon [Anthocephalus cadamba (Roxb) Miq.], coconut (Cocos nucifera L.), and the combination of coconut-jabon and coconut-sengon wood. The analysis of variance revealed that the layer composition of CLT significantly affected the physical and mechanical properties of the beam. While the modulus of rupture met the standard, the moisture content and modulus of elasticity values did not fulfill JAS 1152-2007. All of the CLTs produced in this study demonstrated low formaldehyde emission, ranging from 0.001 mg/L to 0.003 mg/L, thereby satisfying the JAS 1152 for structural glue laminated timber.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.927-935
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• 1997

This study was conducted to investigate the effect of nondigestable substances and calcium such as oligosaccharide, agar, saponin, tannin and calcium on the reduction of lipid status in rats fed high fat diet. In order to make the observation, the lipid content in plasma, liver and the feces, and bile acid excretion were measured of r 4 weeks. the results obtained from this research are as follows. Concentration of total lipid in plasma seemed highest in the control group and were significantly lower in groups oil-gosaccharide, agar and calcium-tannin, compared to the control group. Concentration of total cholesterol in plasma was significantly lower in groups oligosaccharide, agar, calcium and calcium-saponin, compared to the control group. The improvement in lipid status seems to be insignificant with oligosaccharide, showed increase in total bile acids excretion in feces and decrease in total cholesterol in plasma, compared to the control group. These evidence seems to indicate improvement of the plasma lipid status by calcium and agar supplementation.

• Journal of Animal Science and Technology
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• v.57 no.11
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• pp.34.1-34.5
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• 2015

Himalayan dock (Rumex nepalensis) was evaluated for forage value and antinutrients under three, five and seven weeks cutting intervals in the temperate environment. Dry matter (DM) content was measured for each cutting interval. Forage quality parameters such as Crude Protein (CP), Acid Detergent fiber (ADF), Neutral Detergent Fiber (NDF), Calcium (Ca) and Phosphorus (P) were analyzed. Plants with seven weeks cutting interval gave higher DM yield. CP and P content were significantly higher for three weeks cutting intervals. Average CP contents were 31.38 %, 30.73 % and 27.32 % and average P content 0.58 %, 0.52 % and 0.51 % for three, five and seven weeks cutting intervals, respectively. Ca content did not differ significantly between cutting intervals. The average Ca content were 0.91 %, 0.90 % and 90 %, for three, five and seven weeks cutting intervals, respectively. Tannin and mimosine contents were not significantly different between cutting intervals. Average tannin contents were 1.32 %, 1.27 % and 1.26 % and mimosine 0.38 %, 0.30 % and 0.28 % for three, five and seven weeks cutting intervals, respectively. The study concluded that R. nepalensis could be a potential source of protein for livestock. The study also suggests seven weeks harvesting interval to provide plants with high dry matter yield, high forage quality and very low levels of anti-nutrients.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.538-544
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• 2005

The present experiment was conducted to assess the effect of reconstitution (R) on utilization of red sorghum (S) in diets of broiler chickens. Day-old broiler chicks (n=360) were randomly divided into 36 groups of 10 chicks each, and 9 dietary treatments were allotted to 4 groups (replicates) in a completely randomized design. Out of the 9 treatments, one was corn-soy based control (D1). The rest of the treatments were diets consisting of four levels (25, 50, 75 and 100% part of corn) of raw red sorghum (S25-S100) or four levels of reconstituted red sorghum (RS25-RS100). The tannin content reduced from 2.3% to 1.6% after reconstitution of red sorghum. Body weight gain reduced significantly (p<0.01) in diets containing unprocessed red sorghum beyond 33% in diet or reconstituted red sorghum at any level. However, during finishing growth phase the birds receiving either processed or unprocessed sorghum (barring S75) had statistically similar gains in body weight. During over all growth phase (0-6 wk), live weight gains in all the dietary treatments did not differ statistically. Feed intake during 0-6 wk was significantly higher (p<0.05) in diets containing sole red sorghum than corn-soy based control diets Feed conversion ratio during 0-3 wk period in control and unprocessed red-sorghum diets were similar but statistically poorer (p<0.01) FCR emanated from reconstituted groups, while during 3-6 wk of age FCR was poorer (p<0.05) in diets containing 75% red sorghum, either processed or unprocessed. FCR, in overall growth phases, in control diet was statistically similar to the groups fed diets containing up to 33% unprocessed or 16% reconstituted group. The carcass traits and yield of organs did not differ (p>0.05) due to the various levels of red-sorghum. It was concluded that though the tannin content was reduced by 30% by the reconstitution process, but this did not give any additional advantage in broiler performance. More over, red-sorghum can be used effectively up to 33% in diet replacing 50% of corn after proper adjustment of proteins, energy and amino acids.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.99-103
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• 1976

The experiment was tested with fruits of eight varieties which were produced in Kyung Pook and Kyung Nam District and was carried out to investigate the changes of sobuble tannin content, hardness and sugar content during the removal of astringency, and, further more, the changes of quality after the removal of astringency. The results were as follows: 1. Soluble tannin content of Sagoksi was most in eight varieties and than was Euisung-Bansi and Chungdo-Bansi in that order. The time required of the removal of astringency tools 2.5 days in Dansungsi, 4.5days in Sagoksi. 2. Hardness was the firmest in Sagoksi and Chungdo-Bansi and it was gradually decreased as the harvest time of fruits was delayed. 3. In content of sugar, Gojongsi was most amount and Sagoksi was least amount in all varieties. Changes of sugar content showed a gradual decrease during the removal of astringency. 4. Quality of fruit after the removal of astringency was of a very superior quality in Chungdo-Bansi, Sagoksi and Euisung-Bansi.