On Reflectometric Measurement of a Refractive Index of Milk

¹ Department of Physics, University of Joensuu, P.O. BOX 111, FIN-80101 Joensuu, Finland
² Measurement and Sensor Laboratory, Research and Development Centre of Kajaani, University of Oulu, Technology Park 127, FIN-87400 Kajaani, Finland

The refractive index of milk samples was measured with a reflectometer. Fresnel's formula for intensity reflectance and the concept of critical angle were applied to measured data. Milk samples were also measured with surface plasmon resonance sensor for refractive index assessment. The experiments were carried with commercial milk that had fat volume concentrations of 0.004, 1.53, and 3.55%. We observed that simultaneously quantitative information about the refractive index and absorption of milk, as a function of fat concentration, could be obtained with both devices.

Key Words: refractive index • reflectometer • surface plasmon resonance • milk

Submitted on May 16, 2000
Accepted on August 21, 2000

This article has been cited by other articles:

				F. C. Cheong, K. Xiao, and D. G. Grier Technical note: Characterizing individual milk fat globules with holographic video microscopy J Dairy Sci, January 1, 2009; 92(1): 95 - 99. [Abstract] [Full Text] [PDF]

				J. Mutanen, J. Raty, E. Gornov, P. Lehtonen, K.-E. Peiponen, and T. Jaaskelainen Measurement of Color, Refractive Index, and Turbidity of Red Wines Am. J. Enol. Vitic., September 1, 2007; 58(3): 387 - 392. [Abstract] [Full Text] [PDF]