Utilization of hazelnut oil oleogels for the preparation of milk couverture type compound chocolates: Composition, properties, and sensory evaluations

Abstract

The aim of this study was to use oleogels in compound chocolates. A control sample with cocoa butter (CNT) and two compound chocolates with hazelnut oil-sunflower wax oleogel (SWO-CC), and polyglycerol stearate oleogel (PGSO-CC) were prepared with the same recipe. The main properties and compositions of the samples were quite similar. While CNT sample included only 37.97% of total unsaturated fatty acids, it was 74.19 and 63.08% in the SWO-CC and PGSO-CC, respectively. The melting peak temperatures were 32.1, 25.4, and 23.8°C for CNT, SWO-CC and PGSO-CC. The samples had 11.75%, 74.25%, and 74.25% shape retention index values at 60°C. Clearly compound chocolates melted at lower temperatures, but retained their shape at higher temperatures. After 15-day temperature fluctuation storage, no fat bloom was developed. Rheological data showed that the PGSO-CC sample was stiffer among all, and the compound chocolates melted slowly up to 40°C, but CNT melted sharply at 38°C. Further, the PGSO-CC sample showed a lubricating behavior. Although CNT sample included 7 volatile aromatics, SWO-CC and PGSO-CC samples had 17 and 14 compounds, respectively. Trained panel described the samples with 13 attributes, and most profoundly the compound chocolates had lower shape, surface gloss, coffee, bitter, cooling, hardness scores, and higher coating scores. Consumer test revealed that compound chocolates had lower appearance scores, and equal aroma scores. The flavor score and acceptability were highest for the PGSO-CC sample. Overall, this study proved that heat stable and sensorially acceptable compound chocolates could be prepared from the oleogels.