Compatibility between cocoa butter and different milk fat fractions

Abstract: Milk fat and its fractions are often added in chocolate as a texture modifier and bloom inhibitor. The amount that can be added to chocolate is limited by the interactions between cocoa butter (CB) and the different milk fat fractions. This work investigates the compatibility between CB and the three fractions of milk fat: hard-melting fraction (HMF), medium-melting fraction (MMF) and low-melting fraction (LMF). All three fractions of milk fat formed a eutectic with CB but to varying degrees. LMF formed a strong eutectic with CB at high LMF content (³ 60% wt.) especially at 15-25 °C, suggesting that it is highly incompatible with CB within these concentration and temperature ranges. At lower temperatures (15-20 °C), MMF formed a moderate eutectic with CB at high MMF content (60-90% wt.) whereas at higher temperatures (20-30 °C), the eutectic became less severe and occurred mainly with a blend with 50% wt. MMF. Finally, HMF showed a mild eutectic with CB at temperatures > 20 °C and HMF content of 10-20% wt., indicating that it is more compatible with CB than LMF and MMF. These findings provide insight into suitable amount for adding different fractions of milk fat to chocolate in order to avoid detrimental effect on the properties and characteristics of chocolate.