碩士 / 國立海洋大學 / 食品科學系 / 87 / The objectives of this study are to explore the effects of shear rate, solute concentration, solution temperature, NaCl concentration, solution pH and shearing time on the rheological properties of Monostroma nitidum aqueous extracts (aqueous extracts) and to explore the effects of using the aqueous extracts to replace thickening agents and moisture agents in moisture mask formula on rheological properties, water holding capacity and film formation time of moisture mask thus prepared. The results obtained are as follows:
The rheological behavior of aqueous extracts are pseudoplastic fluids. Increasing the solute concentration enhanced shear thinning properties of aqueous extracts. The apparent viscosity of different concentration aqueous extracts decreased with increasing solution temperature, also decreased with increasing NaCl concentration in the solution. The apparent viscosity increased with increasing solution pH. Effect of solution pH on apparent viscosity decreasing rate increased with increasing the concentration of aqueous extracts. The effect of shearing time on the decreasing of shear stress with time are small for those aqueous extracts of low concentration but become remarked at for those higher concentration ones and resulted in decreasing the apparent viscosity.
Increase in the shear stress and the apparent viscosity decreasing rate of moisture masks increased with increasing the concentration of aqueous extracts. The water holding capacity of moisture masks containing 1% aqueous extracts and 1% hydroxyethyl cellulose are better than that containing 2% methyl cellulose and 5% 1-3 butylene glycol. The film formation time of moisture masks containing different concentration of aqueous extracts decreased with increasing the concentration. The stability of moisture mask containing 1% aqueous extracts is better than that containing 2% methyl cellulose. Thixotropy behavior of moisture mask increased with increasing the concentration (from 0% to 1.0%) of aqueous extracts. But as the concentration was increased to 2%, the thixotropy behavior alleviated pronouncedly. The safety test results in no erythema based on the Daize score test. The product pH is between 7.1-7.5.
| Identifer | oai:union.ndltd.org:TW/087NTOU0253014 |
| Date | January 1999 |
| Creators | 陳威宇 |
| Contributors | 陳榮輝 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 90 |
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