Controlling milk protein interactions to enhance the reconstitution properties of whole milk powders – A minireview

Abstract

-Spray-dried milk powders are widely used in recombined milk products and processed foods. The interactions of the specific components in milk, i.e. casein micelles, whey proteins and fat globules, dictate how milk will behave during processing and the functional properties of the powder in different applications. The manufacture of milk powders involves heat treatments, evaporation, homogenisation and spray drying. The major effect of heat treatment is the denaturation of whey proteins and their association with casein micelles. During evaporation, the casein micelle size increases due mainly to the aggregation of some of the micelles and increased association of the whey proteins with the micelles. During whole milk powder manufacture, there are also considerable changes in the size of fat globules and the protein composition of the milk fat globule membrane (MFGM). This modified composition and the consequent reactivity of the MFGM play a major role in determining the functionality of whole milk powders, in particular its reconstitution properties. milk powder / interaction / processing / functionality / solubilityRésumé -Contrôle des interactions des protéines laitières pour favoriser l'aptitude à la reconstitution des poudres de lait entier. Les poudres de lait séché par atomisation sont largement utilisées dans les produits laitiers recombinés et les aliments transformés. Les interactions des composants spécifiques du lait, comme les micelles de caséines, les protéines sériques et les globules gras, conditionnent le comportement du lait au cours du traitement et les propriétés fonctionnelles de la poudre dans différentes applications. La fabrication de poudres de lait implique traitements thermiques, évaporation, homogénéisation et séchage par atomisation. L'effet principal *Corresponding author (通讯作者): H.Singh@massey.ac.nz Dairy Sci. Technol. 90 (2010) 123-136

Functionality of Milk Powders and Milk‐Based Powders for End Use Applications—A Review

“…A combination of high homogenization pressure and high temperature treatment of the concentrate before spray-drying results in poor reconstitution properties of the powder, particularly when heating is carried out after homogenization (Singh and Aiqian 2010). Homogenization of the whole milk concentrates before spray-drying helps to reduce the presence of free fat in the powder.…”

Formation and structure of insoluble particles in reconstituted model infant formula powders

“…Reconstituted milk powder should ideally reflect the organoleptic, nutritional and colloidal properties of fresh milk. However, an issue that is often encountered upon dispersion of the powder in water medium is the presence of insoluble particles (Schuck et al, 2016;Singh & Ye, 2010).…”

“…Protein insolubility is initiated by the unfolding of whey proteins followed by aggregation with casein (Baldwin, 2010;Sharma et al, 2012;Straatsma, Van Houwelingen, Steenbergen, & De Jong, 1999) and in fat-containing systems this results in formation of protein-bridged fat globule clusters (Singh & Ye, 2010). Based on the previous research (De Ruyck, 1991;McKenna et al, 1999;Mol, 1975;Ohba, Takahashi, & Igarashi, 1989) the formation of insoluble material is hypothesised to originate from heat and shear applied during spray drying resulting in changes in fat-protein interactions.…”

Effects of Milk Processing on the Milk Fat Globule Membrane Constituents

“…In the dairy industry, spray drying is the most common method used to concentrate milk solids, due to milk's seasonal variations, and to produce milk-derived powders, especially whole milk powder (WMP) and skim milk powder (SMP) as fresh milk substitutes (Schuck, 2002;Ye et al, 2007;Singh and Ye, 2010). Milk must undergo heat treatments, homogenization, evaporation, and spray drying to produce powders.…”

“…In regard to phospholipids, spray-drying decreases the PL content in buttermilk powders, probably due to complex formations between PL and MFGM proteins from the heat treatment, rapid evaporation, and increased ionic strength created by spray drying (Morin et al, 2007b). In conclusion, milk powder undergoes a lot of processing that causes physical and chemical interactions among milk components, and such interactions determine the functional properties for powder reconstitution in water and consumers' acceptability (Schuck, 2002;Ye et al, 2007;Singh and Ye, 2010).…”