NMR Relaxation and Water Self-Diffusion Studies in Whey Protein Solutions and Gels
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- 作者：Roxane Colsenet ; Franç ; ois Mariette ; and Mireille Cambert
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2005
- 出版时间：August 24, 2005
- 年：2005
- 卷：53
- 期：17
- 页码：6784 - 6790
- 全文大小：135K
- 年卷期：v.53,no.17(August 24, 2005)
- ISSN：1520-5118
文摘
The changes in water proton transverse relaxation behavior induced by aggregation of whey proteinsare explained in terms of the simple molecular processes of diffusion and chemical exchange. Thewater self-diffusion coefficient was measured in whey protein solutions and gels by the pulsed fieldgradient NMR method. As expected, water self-diffusion was reduced with increased proteinconcentrations. Whatever the concentration, the water molecules were free to diffuse over distancesvarying from 15 to 47 
m. Water diffusion was constant over these distances, demonstrating that norestrictions were found to explain the water hindrance. The modification in protein structure by gelationinduced a decrease in water diffusion. The effects of protein concentration on water diffusion arediscussed and modeled. Two approaches were compared, the obstruction effect induced by a sphericalparticle and the cell model, which considered two water compartments with specific self-diffusioncoefficients.Keywords: NMR; diffusion; transverse relaxation; whey; gel
m. Water diffusion was constant over these distances, demonstrating that norestrictions were found to explain the water hindrance. The modification in protein structure by gelationinduced a decrease in water diffusion. The effects of protein concentration on water diffusion arediscussed and modeled. Two approaches were compared, the obstruction effect induced by a sphericalparticle and the cell model, which considered two water compartments with specific self-diffusioncoefficients.Keywords: NMR; diffusion; transverse relaxation; whey; gel