Milk Cholesterol Reduction at Pilot Station Level Using Beta-Cyclodextrin

The objective of this study was to investigate the possibility of cholesterol elimination from milk using beta-cyclodextrin at pilot station scale, because there is very little information considering this level of milk processing. β-cyclodextrin is a nontoxic, edible and chemically stable compound with affinity for nonpolar molecules like cholesterol, giving the opportunity for obtaining food products that can prevent the appearance of cardiovascular diseases. By applying of this procedure, the cholesterol reduction percentage was calculated as approximately 84 %, similar to the values reported by the specialty literature. Except fat and freezing point values, the other parameters values increased with an approximate percentage of 8, indicating a concentration phenomenon due to milk pasteurization. Fat concentration value decreased with 5.9 %, due to the cholesterol inclusion in the beta-cyclodextrin molecule and its elimination at the bottom of the centrifugal separator. However the variation of the parameters is insignificant, so this process could be considered efficient to be applied at a pilot station level.

Oil and water do not mix—hydrophobic hydration

Many surfactants contain hydrocarbon moieties that are removed from their aqueous environment (‘dehydrated’) in, for example, adsorption and micelle formation. Hydrophobic hydration relates to the interactions between individual nonpolar solute molecules and water, and can be probed using thermodynamic quantities for the dissolution of dilute hydrocarbon vapours to form dilute aqueous solutions. Contrary to the simple expectation that the entropy of hydration of a nonpolar moiety should be positive (due to disruption of water structure), it is large and negative, giving a large positive contribution to the free energy of hydration. The hydration of nonpolar molecules in water leads to an attraction between the molecules in close proximity, which is termed hydrophobic bonding. Although the free energy of hydration of nonpolar groups in bulk aqueous solution is positive, the interaction free energy of nonpolar molecules/groups with interfacial water at an air/water interface is negative.