by Nina FILCHAKOVA, Dr. Sc. (Tech.), N. Bauman Moscow State Technical University
Dairy products account for a considerable share of the people's diet. As a complicated dispersion system they constantly attract the interest of researchers in their attempts to reveal the mechanism of interaction between their individual structural elements and the mechanism of their formation.
Stabilizers in the form of mixtures of modified starches, sodium alginate and carrageen are used for the production of high-quality dairy products. For the production, say, of ice cream they are used to preserve the dispersion of the fatty phase. Emulsifiers of the group of mono- and diglycerides and polysorbates are introduced in certain of its varieties. Also used are electrolytes from multivalent cations, concentrates of serum protein, cellulose, gelatin, pectin and other substances.
The mechanism of the stabilizers' action can be explained in many ways. It is believed that their key role consists in hydration* of the surface of the liquid/oil dividing line carried out owing to the polarity of the molecules of such ingredients as mono- and diglycerides, casein. And gelatin, lecithin and sucrose, for instance, have an effect on the condition of milk foam. Certain specialists regard hydrocolloids, in particular, starch and agar-agar**, as the most effective stabilizers, for they considerably increase the viscosity of food liquors, while other specialists believe that solely foam-forming substances are indispensable, such as gums, cellulose (water-bounding) ethers, gelatin, sodium alginate, pectin (gel-forming). Such separation of the functional properties of these substances probably leads to a considerable number of them used as ingredients of food products - from 7 to 11 items.
Difference in the specialists' opinion is attributable to the absence of an objective scientific basis for the choice of stabilizers, for the subject has not yet been sufficiently studied. Meanwhile, it is widely k ... Читать далее