Direct observation of decrease in size of casein micelles during the initial stages of renneting of skim milk

The effect of ultra high-pressure homogenization (UHPH) on rennet coagulation properties of unheated and heated fresh skimmed milk

“…2). This well-known decrease of apparent radius at the early stage of the renneting process is attributed to the change in the hydrodynamics of the casein micelles as the CMP layer is progressively removed (de Kruif & Zhulina, 1996;Horne & Davidson, 1993;Walstra, Bloomfield, Jason Wei, & Jenness, 1981). It is evident from Fig.…”

Structure, Dynamics, and Optical Properties of Concentrated Milk Suspensions: An Analogy to Hard-Sphere Liquids

“…For highly diluted suspensions, when the particles are completely decorrelated, S(q) becomes equal to 1 and Eq. [9] becomes…”

“…We have thus used Percus-Yevick for the calculation of the effective structure factor S(q) together with the corresponding Mie calculation for the scattering function F(q), required in Eq. [9]. For this calculation, we used the same parameters (refractive indices and sizes) that were previously used in the calculation of l * based on Eq.…”

A possible structure of the casein micelle based on high-resolution field-emission scanning electron microscopy

“…On the other hand, it may be necessary to rethink the interpretation of the apparent decreases in micellar size during processes such as renneting (Holt & Dalgleish, 1986) or the addition of ethanol (Horne & Davidson, 1986). Hitherto the changes in micellar diameter (estimated mainly by the application of dynamic light scattering) have implied a simply hairy sphere model with a ''core'' radius (Holt & Dalgleish, 1986;Horne & Davidson, 1993, De Kruif, 1999; modified submicelle models of hairy micelles as depicted by Walstra (1990) were also effectively coat-core models as regards reactivity. However, on the basis of our micrographs, we may argue that not only would the kcasein hairs be subject to collapse, but also the protein tubules themselves would be susceptible to collapse in poor solvent conditions, such as being subjected to ethanol.…”