Liquid Milk Products: Flavored Milks

Flavored milks are unfermented milks mixed with cocoa powder, fruit juice or another ingredient or aroma, with stabilizers, which mostly contain added sugar. They answer the desire of consumers, especially children and young adults, for a change and experience in color and flavor in dairy beverages. Reduction of added sugar is an ongoing goal, to help to improve the nutritional value of such products. Important flavors are chocolate, coffee, vanilla, strawberry, malt extract-chocolate, and banana. Additional ingredients include thickeners (polysaccharides) to stabilize the casein and sometimes pH-stabilizing agents, such as phosphate or sodium hydroxide, are added. Flavored milks with a high percentage of fruit juice are frequently stabilized with about 0.3% (w/w) high-methoxy pectin to avoid the flocculation of milk proteins. The pectin directly interacts with the casein micelles and enhances steric repulsion between the casein micelles. For the stabilization of flavored milk drinks of around normal pH, 6.7, κ-carrageenan is most commonly used as a thickening agent; it adsorbs to the surface of the casein micelles, through electrostatic interaction. The necessary stabilizing weak gel, in terms of a three-dimensional network, occurs at relatively low κ-carrageenan concentrations, of 0.01%–0.05%, within which cocoa particles of 10–30 μm, for example, may be entrapped and prevented from settling. Heat treatment (pasteurization, ultra-pasteurization or UHT) is followed by cooling and filling.