Formulation of milk chocolate using milkfat fractions

Milk chocolate (30% total fat) was formulated by replacing cocoa butter at various concentrations with milkfat fractions from 12.2 to 40% of total fat. Maximum concentration of milkfat addition that produced temperable milk chocolate were up to 40% AMF, MMF and LMF, and up to 35% HMF. Modified tempering procedures were used for milk chocolates containing over 20% milkfat. Degree of temper was evaluated using differential scanning calorimetry (DSC) and expressed as the ratio of enthalpies of melting for the higher stability polymorphs to those of lesser stability. Degree of temper was dependent on the crystallisation time and temperature and the type and quanity of milkfat fraction in the formulation. The solid fat content (SFC), as measured by DSC, of milk chocolate decreased with increasing milkfat addition. At 30°C, the SFC for milk chocolate containing 12.2% AMF was 53.1% and at 40% AMF addition, the SFC was 13.1%. A significant decrease in hardness was observed as the cocentration of milkfat increased. No significant differences in viscosity were detected among all conched samples at 40°C. However, a noted change in milk chocolate viscosity during tempering was observed. During accelerated fat bloom stability studies, milk chocolate samples with 25, 30, 35 or 40% AMF, MMF and HMF remained free of bloom after 100 days. Samples containing LMF at all concentrations bloomed within 37 days. No differences in sweet, milk powder, chocolate and butter flavor or thickness of melt were evident among the formulations. Significant differences in milk flavor and in the textural attributes of hardness, uniformity of mass and onset of melt were observed for increasing concentrations of milkfat. Sensory hardness and onset of melt decreased, and uniformity of mass increased with increasing concentrations of milkfat. No significant differences between the types of milkfat (AMF, HMF, MMF, LMF) were observed for any of the textural attributes tested.