• 한국의류학회지
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• 제29권11호
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• pp.1454-1464
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• 2005

The study was based on a three-stage, non-repetitive factorial experiment in which chemical-rotted kenaf fibers were treated separately with hydrogen peroxide concentrations of $0.5\%,\;1\%\;and\;2\%$, with pH solutions of 7, 9 and 11, and treatment times of 30, 60 and 90 minutes. Under optimal conditions, the study was conducted to determine the strength and elongation of kenaf fibers by the addition of chelators, penetrants and surfactants. The hydrogen peroxide concentration, solution pH and treatment time directly affected the strength of kenaf fibers. The hydrogen peroxide concentration, solution pH affected the elongation of kenaf fibers. It was found, however, that the interaction between pH and treatment time, concentration and treatment time, concentration and treatment time and pH affected the strength of kenaf fibers. Also, It was found that the interaction between pH and concentration, concentration and treatment time, concentration and treatment time and pH affected the elongation of kenaf fibers. Under the hydrogen peroxide conditions of $2\%$ concentration, pH 11 and a treatment time of 60 minutes, there were no effects on the strength and elongation of kenaf fibers with the addition of chelator SP, CA.

• 한국식품과학회지
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• 제27권3호
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• pp.290-293
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• 1995

감자 lipoxygenase가 밀가루반죽의 지질분포, 지방산조성, 카로테노이드 및 색도 등의 화학적 성분 변화에 미치는 영향을 연구하기 위해 감자 lipoxygenase를 밀가루 g당 $6.5{\times}10\;unit$ 수준으로 첨가하여 실험하였다. 밀가루에 감자 lipoxygenase를 첨가하므로서 밀가루 반죽의 과산화물가가 증가하고 지방산조성 중 linoleic acid의 현저한 감소와 함께 유리지질함량이 증가하였다. 효소의 첨가에 의한 유리지질의 증가는 효소에 의한 불포화지방산의 산화와 관련이 있는 것으로 보여진다. 또한 lipoxygenase 첨가에 의해 밀가루 반죽내의 카로테노이드 함량이 낮아져서 효소에 의한 탈색효과가 관찰되었다. 색차계에 의해 측정된 색도 역시 효소첨가로 밀가루 반죽의 적색도와 황색도가 낮아져서 색깔이 옅어졌다.

• 치위생과학회지
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• 제23권4호
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• pp.351-360
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• 2023

Background: The purpose of this study is to investigate the tooth whitening effect of Listerine Healthy White and provide effective management of extrinsic discoloration by comparing the whitening effects of existing whitening products. Methods: The included study four groups: those using whitening gel, whitening toothpaste, and Listerine Healthy White and a control using artificial saliva. Each group received 40 bovine tooth specimens, which were stained with commonly consumed tooth-coloring-inducing foods; black tea, black coffee, and instant noodles for 72 hours. The specimens were treated with tooth whitening materials for 5 weeks, after which the lightness (L^*) was measured weekly using a spectrophotometer. Results: There was a significant difference in lightness among the groups between the 1st and 5th week of treatment for all tooth-coloring-inducing foods (p<0.05). When comparing the changes in lightness values from before whitening to the 5th week of whitening for all tooth-coloring-inducing foods, the order of change was as follows: whitening gel, whitening toothpaste, Listerine Healthy White, and artificial saliva. Listerine Healthy White showed a significant whitening effect for all tooth-coloring-inducing foods (p<0.05). Particularly, changes in lightness values for specimens stained by black tea after 5 weeks of whitening were in the following order: whitening gel (21.72), whitening toothpaste (14.89), Listerine Healthy White (12.91), and artificial saliva (3.85). For specimens stained by black coffee, the changes in lightness values were in the following order: whitening gel (12.99), whitening toothpaste (9.66), Listerine Healthy White (7.91), and artificial saliva (3.12). Lastly, changes in lightness values for specimens stained by instant noodles were as follows: whitening gel (10.84), whitening toothpaste (9.85), Listerine Healthy White (7.71), and artificial saliva (2.61). Conclusion: Listerine Healthy White exhibits continuous whitening effects over time, and for consumers seeking convenient ways to achieve tooth whitening effects at home, consistent use of Listerine Healthy White is recommended.