Whey hydration

Riboflavin also may adsorbed on growing lactose crystals and alter the crystalline habit. Since it is naturally present in the whey from which lactose hydrate is made and is present in all dairy foods, its influence on lactose crystallization may be of special interest. Adsorption is dependent upon concentration of riboflavin in solution, on degree of lactose supersaturation and on temperature (Leviton 1943, 1944 Michaels and Van Krevald 1966). No adsorption occurs below a certain minimum (critical) concentration of riboflavin (2.5 uglml), but adsorption increases linearly with riboflavin concentration above this critical level. Increasing the temperature of crystallization results in reduced riboflavin adsorption. Adsorption is favored at lower supersat-... 

Crystallizing conditions generally favor the production of a-hydrate crystals, but if crystallization occurs above 93.5°C, especially under pressure, anhydrous /3 crystals will be formed. After crystallization has occurred and the product has finally dried, the resulting whey powder is granular and free-flowing, and does not tend to become sticky and caked. 

Calcium precipitation of whey proteins produces a hydrated coagulum. Schmidt et al. (1979) found hardness of whey protein gels to be greatest when 11.1 mM calcium chloride was added, de Rham and Chanton (1984) observed that calcium concentrations critical for precipitation of whey proteins were independant of the calcium-to-protein ratios. 

Lactose occurs as a white to creamy white, crystalline powder. It is normally obtained from whey. It may be anhydrous, contain one molecule of water of hydration, or contain a mixture of both forms if it has been prepared by a spraydrying process. It is soluble in water, very slightly soluble in alcohol, and insoluble in chloroform and in ether. 

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