Composition and Structure of Fat Globule Surface Layers in Recombined Milk

Abstract

Protein coverage, composition and structure of surface layers of fat globules in recombined milk were determined. Average protein load was ϳ6 mg/m 2 fat surface. Both casein and whey proteins were present in the fat globule surface layer, with casein adsorbed in preference to whey proteins and ␣ s (␣ s1 ϩ␣ s2 )-casein adsorbed in preference to ␤-casein. Transmission electron microscopy showed that the surface layer of fat globule was made up of casein micelles, fragments of casein micelles and a thin layer of protein, possibly whey proteins. Experiments with surface layers that had been dispersed in EDTA showed that the extent of dissociation of caseins followed the order: ␤-casein Ͼ ␣ s -casein ϾϾ -casein, suggesting that most of the -casein was probably associated directly with the fat surface.

Influence of enzymatic cross-linking on milk fat globules and emulsifying properties of milk proteins

“…4), signs of clustering were observed only when skim milk was incubated with TGase for 24 h and the recombined milk was homogenised at 800 bar. Sharma, Singh, and Taylor (1996) reported that spreading of casein micelles is more pronounced in recombined milk than in raw whole milk, leading to a lower protein surface load in the former. Hence, at similar protein and fat contents, a more extensive formation of clusters would be expected in raw whole milk than in recombined milk which may explain the results found here.…”

Focus on the supramolecular structure of milk fat in dairy products

“…Their results are in agreement with studies performed with heat treated and homogenised milks. Considering the organisation of proteins, it has been shown that the milk fat globule surfaces were covered with (i) intact casein micelles, (ii) partially spread casein micelles, (iii) smaller particles, which probably result from the desintegration of casein micelles and (iv) a thin layer of proteins, which was probably whey proteins [27,28]. The sequence of homogenisation and heating changes the structure and the composition of the synthetic FGM [25].…”

Technical difficulties and future challenges in isolating membrane material from milk fat globules in industrial settings – A critical review

“…Britten et al (2008) showed that the total protein content of buttermilk (including caseins, whey proteins, and MFGM proteins) was reduced from 24.5 g L À1 to 5.2 g L À1 after one washing step with 10 times the starting volume of UF Saline solution (0.9% NaCl) Cavaletto et al, 1999;Cebo et al, 2010;Fortunato et al, 2003;Keenan et al, 1971;Patton, 1982 Phosphate Cavaletto et al, 1999;Cebo et al, 2010;Dickow et al, 2011;Horisberger et al, 1977;Kathriarachchi et al, 2014;Liao et al, 2011;Mather & Keenan, 1975;Nejjar et al, 1986;Ong et al, 2010;Patton, 1982;Patton & Huston, 1986;Sharma et al, 1996;Ye et al, 2002;Zamora et al, 2012;Zheng et al, 201330e45 C Jenness & Palmer, 1945Montagne et al, 1999;Oehlmann et al, 1994;Shimizu & Yamauchi, 1982;Wiese & Palmer, 1932 1000e3000 (low) Cavaletto et al, 1999;Cebo, Caillat, Bouvier, & Martin, 2010;Chien & Richardson, 1967;Dalgleish & Banks, 1991;Dickow, Larsen, Hammershøj, & Wiking, 2011;Fortunato et al, 2003;Horisberger et al, 1977;Iametti et al, 1997;Kathriarachchi et al, 2014;…”

“…Overview of various washing conditions using lab-scale centrifuges Kim & Nawar, 1992;Liao, Alvarado, Phinney, & L€ onnerdal, 2011;Montagne et al, 1999;Nejjar et al, 1986;Patton, 1982;Reinhardt & Lippolis, 2006;Sharma et al, 1996;Shimizu & Yamauchi, 1982;Vanderghem et al, 2008;Zheng et al, 2013. …”