Abstract:
The aim of this study was to utilize grape pomace, as a polyphenol-rich by-product of wine
production, in the manufacture of enriched cocoa spread. The formulation of the cocoa spread has
been modified by substitution of refined sunflower oil with cold-pressed grape seed oil. The spread
with grape seed oil (Cg) was further enriched with grape seed extract encapsulated on maltodextrins
(E), where 10% and 15% of E was added to Cg obtaining the samples Cg10 and Cg15. The results
showed an increase in volume-weighted mean in spread samples, from 19.17 m in Cg to 19.71 m in
Cg10 and 21.04 m in Cg15. Casson yield stress and Casson viscosity significantly (p < 0.05) increased
from 16.41 Pa and 1.58 Pa s in Cg to 29.45 Pa and 5.70 Pa s in Cg15 due to the reduction of the fat-phase
content in enriched spreads. The addition of E had no significant effect on the melting temperature
(Tpeak) of the enriched spreads, while increasing the amount of E significantly (p < 0.05) increased
their hardness. The incorporation of grape seed oil in the cocoa spread formulation contributed to
an increase in total polyphenols and flavonoids. Moreover, the addition of 10% and 15% of E to Cg
resulted in approximately 1.5 and 2 higher content of phenolic compounds in Cg10 and Cg15
compared to control spread with sunflower oil (Cs). Flavonoids increased from 0.43 mg CE/g in
Cs to 0.74 mg CE/g in Cg 10 and 1.24 mg CE/g in Cg15. Encapsulates positively affected sensory
characteristics of enriched spread samples by reducing their grape seed oil aroma and sweetness.
