Stability of chocolates enriched with cocoa shell during storage

The stability of chocolate is mainly influenced by cocoa butter re-crystallization during storage, shown through fat bloom (appearance of white layers of cocoa butter on chocolate surface). The aim of this study was to examine the influence of cocoa shell addition on stability of dark and milk chocolate over one year storage period.

Dark and milk chocolates were produced in a ball mill. Four chocolates were produced, two with the addition of cocoa shell (5% in milk and 15% in dark) and two control chocolates without the addition. Chocolates were stored at room temperature. The effect of cocoa shell on chocolate stability was examined by determining total color change and whiteness index (calculated from parameters L*, a* and b* determined using chromameter), total polyphenol content (TPC) (by Folin Ciocalteau method) and thermo-physical properties (using differential scanning calorimetry).

Total color change and whiteness index were lower in chocolates with cocoa shell than in control samples. Over a period of one year, milk and dark chocolate with cocoa shell had lower melting enthalpy of fat on the surface of chocolate. Total polyphenol content in all chocolates did not change significantly through the storage period, although chocolates with cocoa shell had lower TPC because the part of the cocoa liquor was replaced with cocoa shell. From these results, it can be concluded that chocolates enriched with cocoa shell are stable during storage and that the shell actually positively affects fat melting enthalpy and total color change of chocolates.

Funding: This work has been supported in part by Croatian Science Foundation under the project “Application of cocoa husk in production of chocolate and chocolate-like products” (UIP 2017-05-8709).