EVALUATION OF MILK-FAT FRACTIONATION AND MODIFICATION TECHNIQUES FOR CREATING COCOA BUTTER REPLACERS

The utilization of milk fat fractions or interesterified milk fat frac tions in chocolate confectionery was examined. Anhydrous milk fat was fractionated by two methods: multiple step melt crystallization; and s upercritical carbon dioxide extraction. The middle-and high-melting fr actions were then interesterified using an immobilized lipase under co nditions of CO2 at atmospheric pressure or CO2 at supercritical pressu res. Milk fat and milk fat fractions were used to prepare mixtures wit h cocoa butter which were analysed for solid fat content using nuclear magnetic resonance. Isosolid diagrams were prepared from solid fat da ta to evaluate interactions between milk fat and cocoa butter. Experim ental milk chocolates with 10% or 20% of the cocoa butter replaced by milk fat fraction were evaluated. These chocolates also contained inta ct milk fat added as whole milk powder during conching. Evaluation of cocoa butter/milk fat mixtures indicated that the high-melting fractio n produced by melt crystallization was more compatible with cocoa butt er than anhydrous milk fat, particularly after interesterification und er atmospheric or supercritical conditions. No other fraction, native or modified, displayed significantly increased compatibility. Evaluati on of experimental milk chocolates demonstrated that chocolates prepar ed with modified high-melting fractions replacing 10% of the cocoa but ter were significantly harder than chocolates containing 10% of any ot her milk fat fraction, native or modified. However, these chocolates w ere still significantly softer than the control chocolate. More potent ial may exist for using milk fat fractions in dark chocolate than for milk chocolate, which already contains milk fat.