Effect of nettle seed powder supplementation on quality properties of cakes

In this study, crust and crumb color, specific volume, microstructure, antimicrobial activity, total phenolic substance, antioxidant activity and sensory analyzes were performed in 4 cake groups: without addition of nettle seed powder (IT0), with addition of 1% (IT1), 3% (IT2) and 5% (IT3) nettle seed powder. The addition of nettle seed powder to the cakes significantly (p<0.001) reduced the values for crust (L*, a* and b*) and crumb color (L* and b*). There was no statistically significant change in specific volume. The total phenolic substance content in the cake samples ranged from 3.58 to 4.8 mg gallic acid equivalent (GAE)/g, and there was a statistically significant (p<0.001) increase in the amount of phenolic substance with the addition of nettle seed powder. It was found that the antioxidant activity of the samples, i.e. the elimination rate of superoxide (O2•–), hydroxyl (OH•), nitric oxide (NO•), 2,2-diphenyl-1- picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicals and iron reduction potential increased with increasing nettle seed concentration. The sensory analysis parameters of the cake samples except for crust and internal color (top surface characteristics, softness of the cake, aroma and mouthfeel, internal pore structure of the cake, taste and overall acceptability) were found to be statistically significant. Therefore, the samples of group IT2 can be recommended as a different product type for cake products.