Types of fillings

Hard candy may be filled with centers that remain soft after the candy has hardened. This provides a contrast between texture and flavor. Such fillings are either fat based or water based. When water-based fillings are used, the water content of the filling is of paramount importance, as an excess of water will attack the hard candy from the inside out, causing crystallization. For all water-based fillings, the total water content must not exceed 15 to 18 percent. These fillings typically consist of low-moisture jams, glucose syrup, or invert sugar; they may also contain fats.