Tag Archives: particle size distribution.

753-758 H. Mootse, A. Pisponen, S. Pajumägi, A. Polikarpus, V.Tatar, A. Sats andV. Poikalainen
Investigation of Casein Micelle Particle Size Distribution in Raw Milk of Estonian Holstein Dairy Cows
Abstract |
Full text PDF (343 kB)

Investigation of Casein Micelle Particle Size Distribution in Raw Milk of Estonian Holstein Dairy Cows

H. Mootse*, A. Pisponen, S. Pajumägi, A. Polikarpus, V.Tatar, A. Sats andV. Poikalainen

Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 56/5, EE51014 Tartu, Estonia; *Correspondence: hannes.mootse@emu.ee

Abstract:

The particle size of milk influences its microstructure and defines many properties of dairy products such as colloidal stability, texture etc. Differences in particle size can significantly affect milk processing especially when membrane technology is used. Aim of this investigation was to estimate casein micelle size in the raw milk of Estonian Holstein dairy cows and its variability concerning individual animals. Milk samples were collected during 12 months with the interval of 25–35 days. DLS analyses were performed using a Malvern Zetasizer Nano ZS (Malvern Instruments Ltd, Malvern, UK). Average mode of casein micelle particles size in raw milk of 44 cows was 171.13 nm with the variation range 70.1 nm and its distribution resembled a normal one. Casein micelles size mode of individual cows varied in a wide range from 148.5 (with variation range 18.2) to 194.1 (with variation range 27.6) nm which may be caused by differences in physiological and health status, stage of lactation and other factors concerning milk production.

Key words:

, , ,




801-806 A. Sats, H. Mootse, S. Pajumägi, A. Pisponen, V. Tatar and V. Poikalainen
Estimation of Particle Size Distribution in Bovine Colostrum Whey by Dynamic Light Scattering (DLS) Method
Abstract |
Full text PDF (218 kB)

Estimation of Particle Size Distribution in Bovine Colostrum Whey by Dynamic Light Scattering (DLS) Method

A. Sats*, H. Mootse, S. Pajumägi, A. Pisponen, V. Tatar and V. Poikalainen

Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal Sciences, Department of Food Science and Technology, Kreutzwaldi ⁵⁶/⁵, EE⁵¹0¹⁴ Tartu, Estonia; *Correspondence: andres.sats@emu.ee

Abstract:

Colostrum whey consist bioactive compounds in considerable concentration. For isolation of these compounds the particle size has crucial importance. The aim of this work was to study possibilities of using dynamic light scattering method – DLS (Malvern Zetasizer Nano ZS) for colostrum whey particle size distribution estimation. The first and second milking colostrum samples were skimmed by centrifugal separation and casein of these was enzymatically coagulated by rennet (chymosin). Obtained whey was diluted (¹:²00) by distilled water and filtered (cut-off 0.⁴⁵ m) to get probes for estimation of particle size. Particle size distribution in colostrum whey probes had maximally three peaks and polydispersity indices from 0.¹⁵⁷ to 0.⁵⁴¹. Prevailing peak of the distribution was found at size from ¹⁴⁴ to ²¹0 nm, which apparently corresponds to hydrodynamic diameter of immunoglobulin IgG¹.

Key words:

, , , ,