Effect of grape pomace usage in chocolate spread formulation on textural, rheological and digestibility properties

In this study, dried grape (Cabernet sauvignon) pomace (DGP) as a by-product of wine production was used in the chocolate spread (CS) instead of various amounts of sugar and milk originated powders (MOP; skimmed milk and demineralized whey powder 1:1, w/w). The formulations of CS samples were determined using mixture design method. The sugar, MOP and DGP concentrations changed between 35 and 50, 0.066-8.000 and 0.23-15 g/100 g, respectively. According to the results, the consistency coefficient (K) and flow behavior index values of CS samples changed between 8.10 and 28.50 Pas.s(n) and 0.52-0.71, respectively. In addition, firmness and spreadability parameters were determined between 0.80-1.42 N and 2.15-4.24 N mm, respectively. Total phenolic content in CS samples ranged from 3415 to 13,754 mg GAE/kg and their digestibility ranged between 25% and 84%. Also, the digestibility of resveratrol was determined between 47.6% and 95.7% at different DGP concentrations. All of the established models successfully described the relation with R-2 values higher than 0.800. Textural and rheological parameters as well as sensory characteristics of the samples indicated that DGP may be used as a healthy and low-cost ingredient in CS formulation to partially substitute sugar and MOP.

Automated summary

In this study, dried grape pomace was successfully used as an alternative ingredient in chocolate spread, leading to changes in formulation and properties such as hardness, spreadability, and phenolic content. This research demonstrates the potential application of dried grape pomace in food products as a healthy and cost-effective ingredient.