• 한국식품영양과학회지
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• 제42권5호
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• pp.774-783
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• 2013

본 연구는 녹차, 오룡차, 홍차 추출물 0.5, 1, 1.5, 2%를 비육돈육(B 등급) 등심 수육에 첨가하여 수육의 일반성분, 보수력, 경도, pH, 색도, 미생물 수준, 휘발성 염기질소, TBARS, 관능검사의 품질특성을 측정하였다. 녹차의 수분 함량은 3.4%, 조단백질 31.8%, 조회분 5.5%, 탄수화물 57.7%였으며 차 종류에 따른 유의적인 차이는 없었다. 그러나 조지방은 녹차 1.6%, 오룡차 1.0%, 홍차 0.9%로 녹차의 조지방 함량이 오룡차나 홍차보다 유의적으로 높았다(p<0.05). 돼지고기 수육의 수분 함량은 55.1%, 조단백질 38.6%, 조지방 5.2%, 조회분 0.9%이었다. 보수력은 모든 차 추출물 첨가 수육에서 유의적으로 증가하였으며(p<0.05) 차 종류에 따른 차이는 없었다. 경도는 모든 차 첨가 수육에서 추출물 농도가 높아질수록 유의적으로 증가하였으며(p<0.05) 홍차 수육이 녹차와 오룡차 수육보다 경도가 낮았다. 수육의 pH는 제조일에는 각 처리구와의 유의적인 차이는 없었다. 그러나 저장기간이 경과함에 따라 무처리 수육과 모든 차 0.5% 수육에서 pH는 유의적으로 감소하였으나(p<0.05) 1, 1.5, 2% 녹차, 오룡차, 홍차 수육에서는 저장 중 pH의 유의적인 차이는 없었다. 녹차 수육은 추출물 농도가 증가할수록 명도와 황색도는 감소하였고 적색도는 감소하다가 2% 녹차 수육에서는 증가하여 0.5% 녹차 수육과 같은 수준이었다. 오룡차 수육은 추출물 첨가 농도가 증가함에 따라 명도와 황색도는 감소하였고 적색도는 증가하였다. 홍차 수육은 추출물 첨가 농도가 증가함에 따라 명도, 적색도, 황색도가 유의적으로 감소하였다. 미생물 수준은 모든 차 처리 수육에서 추출물 농도가 증가함에 따라 미생물 수준이 유의적으로 낮았으며(p<0.05) 저장 기간이 증가함에 따라 미생물 수준이 증가하였다. 수육의 휘발성 염기질소 함량은 제조일에는 각 처리구와의 유의적인 차이는 없었으며 저장 기간이 경과함에 모든 수육에서 유의적으로 증가하였다(p<0.05). TBARS 값은 제조일에는 무처리 수육보다 1, 1.5, 2% 녹차 수육과 오룡차 수육, 모든 홍차 수육이 유의적으로 낮았으며, 저장 기간이 경과함에 따라 모든 수육에서 TBARS 값이 높아졌다. 관능검사 결과 홍차와 오룡차 1% 추출물 첨가 수육이 색, 향, 종합적 기호도의 점수가 가장 높았으나 유의적인 차이는 없었으며 맛 점수는 유의적으로 높았다. 이상의 결과를 종합하여 볼 때 녹차보다 오룡차와 홍차 추출물의 첨가가 돼지고기 수육의 이취를 감소시키고, 특유의 색상을 부여하여 관능적 품질을 향상시킬 뿐만 아니라 가열 조리 및 저장 중 지방산패를 방지하여 품질 변화를 최소화하는데 효과적인 것으로 평가되었다. 특히 돼지고기 수육의 품질향상을 위해서는 홍차 추출물의 이용이 가장 좋았으며 오룡차와 홍차 추출물의 최적 첨가 농도는 1%로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1190-1196
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• 2006

This experiment was carried out to investigate the effects of Korean, Japanese and Chinese green tea on laying performance and egg quality in hens. A total of 168 "Tetran Brown" hens aged 40 weeks were assigned to 7 treatments in a completely randomized design. Each treatment had 4 replicates accommodating 6 layers per replication. The seven dietary treatments were: 1) control diet with no green tea added, 2) diet containing 1.0% Korean green tea (1.0% KGT), 3) diet containing 2.0% Korean green tea (2.0% KGT), 4) diet containing 1.0% Japanese green tea (1.0% JGT), 5) diet containing 2.0% Japanese green tea (2.0% JGT), 6) diet containing 1.0% Chinese green tea (1.0% CGT), and 7) diet containing 2.0% Chinese green tea (2.0% CGT). Egg production rate of the layers fed diets containing 1.0 or 2.0% green tea powders were significantly increased compared to that of the control (p<0.05). The egg weight of layers was significantly reduced in layers fed 1.0% CGT (p<0.05). The feed intake was significantly decreased in KGT and CGT groups at 2.0% inclusion levels (p<0.05). The egg shell thickness and shape index of JGT treatment was significantly lower than that of the control (p<0.05). There were no significant differences in albumen index, yolk index and Haugh unit of eggs for layers fed diets containing green tea powders regardless of origin (p>0.05). Green tea feeding to layers tended to reduce the overall cholesterol content of egg yolk. Particularly, 1.0 or 2.0% CGT significantly depressed the total cholesterol content of egg yolk (p<0.05). In conclusion, incorporation of 1.0 or 2.0% Korean, Japanese and Chinese green tea into layer diets regardless of origin had favorable effects on laying performance and egg quality profiles. Among the three green tea sources, the Chinese green tea powder had the highest reducing effect on cholesterol content in egg yolk.

• 한국식품저장유통학회지
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• 제8권2호
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• pp.206-212
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• 2001

Water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activity. The sensitivity of Staphylococcus aureus and Salmonella typhimurium to the green tea extracts in various pH of culture broth was tested. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts was adjusted to pH 5.0∼7.0 and inoculated with 10$\^$5/∼10$\^$6/ cells/ml of each bacteria. The plate counting method and clear zone test were used to determine inhibitory effect of green tea extracts. Green tea extracts completely inhibited the growth of S. aureus at 0.5% level and bactercidal at 0.5∼1.0% level of GTW and GTE at pH 5.0∼7.0. Green tea extracts were bactercidal to S. typhimurium at 1.5∼2.0% level of GTW and 1.0∼2.0% level of GTE at pH 7.0. Sal. typhimurium was more resistant than S. aureus. in same concentration of green tea extracts at same pH. The resistance of S. aureus and Sal. typhimurium was increased with decreasing pH of culture broth. The morphology of S. aureus cells treated with green tea extracts showed damage of cell wall and cytoplasmic membrane. Severely damaged cells of S. aureus lost electron dense material and cytoplasm. Green tea extracts stimulated autolysis and cell death of S. aureus. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

• 한국식품영양과학회지
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• 제21권6호
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• pp.595-600
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• 1992

본 연구는 흰 쥐에 있어서의 식이단백질 수준, 카페인 또는 녹차가 체지방 축적에 미치는 영향을 검토하였다. 실험동물은 체중 90g 전후의 이유기후의 수컷 Wistar rat를 사용하여 식이단백질 수준을 달리하여, 카페인 또는 녹차의 첨가유뮤로 6군으로 나누어 8주동안 실시하였다. 그 결과 요약하면 다음과 같다. 5% PEP 수준에 있어서 카페인 또는 녹차문말을 첨가한 군의 체중 및 사료효율이 유의하게 낮았다(p<0.05). 카페인 또는 녹차분말을 첨가한 5% PEP 수준에서 체중 및 백색지방조직의 중량이 유의하게 감소하였다(p<0.01). 카페인 또는 녹차를 첨가한 5% PEP 수준에서 혈장 및 간장중의 triglyceride 농도가 유의하게 감소하였다(p<0.01). 이와 같은 영향은 녹차첨가군에서 현저하게 나타났다. 5% 및 15% PEP군에 카페인 또는 녹차분말을 첨가한 군에서 혈장 콜레스테롤, 유리 콜레스테롤 및 콜레스테롤 에스테르의 수준이 대조군에 비해 유의하게 높은 것이었다(p<0.01). 반면에 HDL 콜레스테롤 수준은 유의하게 높은 값이었다(p<0.01). 특히 6.1% 녹차분말 첨가군에서의 동맥경화지수가 대조군에 비해 현저하게 낮게 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권10호
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• pp.1486-1494
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• 2008

The objective of this experiment was to compare the effects of green tea by-product and green tea probiotics on the growth performance, meat quality and immune response of finishing pigs. A total of 72 crossbred "Landrace$\times$Yorkshire" finishing pigs with an average of 76 kg body weight were assigned to 4 dietary treatments in a completely randomized design. Each treatment had 3 replications with 6 pigs per replication. The four dietary treatments were control, antibiotics (control diet with 0.003% chlortetracycline added), and diets containing 0.5% green tea by-product or 0.5% green tea probiotic supplementation. Weight gain was increased in 0.5% green tea probiotics treatment compared to others, but there was no significant difference (p>0.05). The incorporation of 0.5% green tea probiotics to diets reduced the feed conversion ratio in finishing pigs (p>0.05). The incorporation of 0.5% green tea by-product into the pig diet reduced the crude protein and fat contents of the meat (p>0.05). Pigs fed diets containing 0.5% green tea probiotic supplementation had lowered meat TBA values compared to those fed 0.5% green tea by-product (p<0.05). The proliferation of spleen cells stimulated with Con A (concanavalin: 0.1, 0.3, and $1.0{\mu}g/ml$) significantly increased with 0.5% green tea by-product treatment compared to antibiotic treatment (p<0.05), but was significantly decreased in 0.5% green tea probiotics treatment compared to the antibiotic treatment (p<0.05). When stimulated with $1.0{\mu}g/ml$ Con A, splenocyte production of IL-6 from pigs treated with 0.5% green tea by-product or green tea probiotics was significantly increased compared to the antibiotic treatment group (p<0.05). Splenocyte production of TNF-${\alpha}$ after treatment with $1.0{\mu}g/ml$ Con A was significantly higher following 0.5% green tea probiotics treatment (p<0.05), while TNF-${\alpha}$ production after $10.0{\mu}g/ml$ LPS (lipopolysaccharide) was significantly higher in the 0.5% antibiotic treatment group (p<0.05).

• 생명과학회지
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• 제6권2호
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• pp.104-110
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• 1996

The present study was conducted to elucidate the functional property of tea extract obtained from tea extracts, semi-fermented tea(oolong tea) and fermented tea(black tea). Tea extracts exhibited remarkable nitrite-scavenging actions, and the action increased with the increased of the amount of tea extracts. The nitrite-scavenging actionof tea extracts showed pH dependent, highest at pH 1.2 and lowest at pH6.0. The nitrite-scavenging rate in tea extracts/amine/nitrite systems proved to be faster than that in amine/nitrite systems. To screen the nitrite-scavenging factors, tea extracts were fractionated into water-soluble, methanol-soluble, methanol-precipitate and crude catechin fraction. Among these fractions of tea extracts, the crude catechin fraction possessed greater nitrite-scavenging action than the other fractions. The nitrite-scavenging action of tea extracts increased with the contents of total phenols and an absorbance at 280nm, nitrite-scavenging factors were supposed to be and catechins in tea polyphenol compounds.

• Asian-Australasian Journal of Animal Sciences
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• 제21권9호
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• pp.1339-1347
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• 2008

The objective of this study was to determine the effects of green tea probiotics on growth performance, meat quality and immune response in finishing pigs, and to assess the possibility of substituting green tea probiotics for antibiotics in diets of finishing pigs. This green tea probiotics is made by mixing green tea powder and excipients (defatted rice bran and wheat bran) and fermenting the mixture with beneficial bacteria. A total of 90 crossbreed "Landrace$\times$Yorkshire" finishing pigs with an average body weight of $72.5{\pm}2.5kg$ were assigned to 5 dietary treatments in a completely randomized design. Each treatment had 3 replications with 6 pigs per replication. The five dietary treatments were control, antibiotic (0.003% chlortetracycline added) and 0.1, 0.5 and 1.0% of green tea probiotics. There were no significant differences in final body weight, daily weight gain, daily feed intake and feed conversion ratio in the green tea probiotics and antibiotic treatments (p>0.05). Crude protein content was significantly increased in the 0.1 and 1.0% green tea probiotics treatment groups (p<0.05) and there was no significant difference in crude fat content of the meat among the treatments. The TBA value of meat was significantly lowered with 0.5 and 1.0% green tea probiotics treatments compared to that of controls and statistically similar to the antibiotic treatment after 3 weeks of storage (p<0.05). The growth of spleen cells stimulated with Con A (0.1 and $1.0{\mu}g/ml$) was significantly increased with 1.0% green tea probiotics treatment compared to that of the control treatment (p<0.05). The growth of spleen cells stimulated with LPS (1.0, 3.0 and $10{\mu}g/ml$) was significantly increased in the 0.5% green tea probiotics group compared to the antibiotic group (p<0.05). In Con A ($1.0{\mu}g/ml$) medium, IL-6 production of spleen cells was significantly increased with 1.0% green tea probiotics treatment compared to that of the control (p<0.05). In LPS ($10.0{\mu}g/ml$) medium, TNF-${\alpha}$ production of spleen cells increased significantly in all green tea probiotics treatment groups compared to that of the control (p<0.05). Finally it can be summarized that addition of green tea probiotic has a positive effect similar to antibiotic and 0.5% is the suitable dietary supplementation dose for finishing pig production.

• 한국식품영양학회지
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• 제13권1호
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• pp.36-44
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• 2000

Survival of pathogenic bacteris(S. aureus, L. monocytogenes, E. coli and S. typhimurium) in tryptic soy broth containing green tea water extract(GTW), green tea ethanol extract(GTE), potassium sorbate (PS) and sodium benzoate(SB) stored at various pH was evaluated. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts and preservatives adjusted to pH 5.5, 6.0, 6.5 and 7.0 was inoculated approximately 105 CFU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 24∼48 hours. Survival of bacteria was determined by viable cell counts of bacterial culture at each pH. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) of green tea extracts and preservatives against pathogenic bacteria were derived from survival curves of each bacteria. Antibacterial activities of green tea extracts increased with increasing pH but those of preservatives decreased with increrasing pH. S. aureus was the most sensitive strain to GTW and GTE but the most resistant to PS and SB. The MICs of green tea extracts to S. aureus were 0.52∼0.98% at pH 5.5∼6.0 and non inhibitory at pH 7.0. S. typhimurium was the most resistant to green tea extracts while the most sensitive to SB. The MICs of green tea extracts to S. typhimurium were 0.46∼1.62% at pH 5.5∼6.0 and 2% of PS was bactericidal at pH 5.5. 1.0∼2.0% of GTE were bactericidal to all strains tested except L. m9oncytogenes at pH 7.0. GTE was most efficient at inactivating pathogenic bacteria, generally followed by GTW, PS and SB.

• 대한수의학회지
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• 제42권4호
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• pp.475-483
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• 2002

We performed this study to determine the effect of Korean favorite teas (green tea, ginseng tea, coffee and barley tea) on jejunal crypt survival, endogenous spleen colony formation and apoptosis in jejunal crypt cells of mice irradiated with high and low dose of ${\gamma}$-radiation. Jejunal crypts were protected by pretreatment of green tea (P.O.: 1.25% water extract, for 7 days before irradiation., I.P.: 50 mg/kg of body weight, at 12 and 36 hours before irradiation, p<0.01) or ginseng (I.P.: 50 mg/kg of body weight, at 12 and 36 hours before irradiation, p<0.05). Green tea (p<0.05) or ginseng (p<0.05) administration before irradiation (I.P. at 12 and 36 hours before irradiation) resulted in an increase of t formation of endogenous spleen colony. The frequency of radiation-induced apoptosis was also reduced by pretreatment of green tea (P.O.: p<0.005, I.P.: p<0.05), pretreatment of ginseng (P.O.: p<0.005, I.P.: p<0.005) or posttreatment of ginseng (I.P.: 50 mg/kg of body weight, at 30 minutes after irradiation, p<0.05). Treatment with coffee or barley tea showed no significant modifying effects on the radiation-induced damages. These results indicated that green tea and ginseng might be a useful radioprotector, especially since it is a relatively nontoxic natural product. Further studies are needed to characterize better the promotion nature of green tea, ginseng and its components.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1769-1774
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• 2005

This experiment was carried out to evaluate the effects of feeding green tea powder on laying performance and egg quality in hens. A total 180 'Tetran Brown' laying hens aged 40 weeks were assigned to 6 treatments in a completely randomized design. Each treatment consisted of five replicates accommodating six layers per replication. The experimental diets were a negative control containing no green tea, a positive control diet containing antibiotics (0.05% chlortetracycline) and diets containing 0.5%, 1.0%, 1.5% and 2.0% green tea powder. Egg production rate of layers fed the diets containing green tea powder did not differ significantly from that of the negative and positive controls (p>0.05). Egg weight was decreased significantly in the group fed the diet containing 0.5% green tea powder (p<0.05). Feed intake of layers was significantly higher for the diet containing 1.5% green tea powder compared to that of negative and positive control diets (p<0.05). The eggshell thickness reduced significantly in the layer group fed the diets containing green tea powder regardless of dietary levels (p<0.05). Green tea powder tended to reduce egg yolk cholesterol in this experiment. Particularly, dietary 2% level of green tea powder significantly suppressed the cholesterol contents of the egg yolk (p<0.05). Thiobarbituric acid value (TBA) of egg yolk was significantly reduced by green tea diets (p<0.05). The yellowness of egg yolk was increased in the layers fed the 2.0% green tea diet compared with that of control diet (p<0.005). The Linoleic and $\alpha$-linolenic acids tended to increase in the group fed diets containing 1.5% green tea powder even though there were no significant differences among treatments (p>0.05). The oleic and docosahexaenoic acid contents of the egg yolk were similar among treatments (p>0.05). Based on the results of the experiment, it is concluded that green tea powder inclusion in the diet for layers at 2.0% level can reduce the cholesterol content and TBA value of the egg yolk, implying its potential effect on egg quality parameters.