2015 年 41 巻 4 号 p. 194-204
Chocolate is a suspension in which solid particles of sugar and cocoa powder are dispersed at high concentrations in a continuous phase of cocoa butter. Many of chocolate's physical properties are thus determined by the behavior of cocoa butter crystal, which plays numerous essential roles in providing chocolate with a pleasing appearance, snap at room temperature, and smooth melting in the mouth. On the other hand, a fat bloom appears on chocolate when the unfavorable properties of cocoa butter crystal are manifested. Fat bloom is a condition in which the fine texture of fat crystal is lost for some reason and the chocolate becomes non-uniform. Chocolate fat bloom is classified into various types by the form of chocolate it is found on and the storage conditions that cause it. However, the relationships between the causes and results of bloom are diverse, and the classification of chocolate fat bloom is complicated. In this article, we classify chocolate fat bloom according to bloom morphology. Organizing the morphological states can help us to understand the developing mechanism, which gives a complicated flow chart showing the dependence on the type of chocolate item and its storage conditions.