Breadstick fortification with red grape pomace: effect on nutritional, technological and sensory properties

Abstract

Background: Grape pomace (GP), a wine-making by-product rich in dietary fiber (DF) and total phenolic compounds (TPC), is a potential functional ingredient in the fortification of baked goods.

Results: In the present study, fortified breadsticks samples were obtained by replacing wheat flour with 0, 5 and 10 g 100 g^-1 of powdered GP (GPP). The GPP inclusion affected the rheological properties of the doughs by increasing the water absorption and tenacity (P) at the same time as reducing the extensibility (L), with a significant increase in the P/L value and a decrease in the swelling index (G) value and deformation energy (W). Textural characteristics of breadsticks were influenced by the GPP addition, showing a reduction in hardness and fracturability as the amount of GPP increased in the recipe. The GPP fortified breadsticks exhibited decreased pH, volume and specific volume values compared to the control. The TPC and the antioxidant capacity increased in GPP fortified breadsticks, whereas the increased amount of DF allowed the products to benefit from the claim 'high fiber content' at the highest level of GPP inclusion. The sensory evaluation revealed that GPP addition increased wine odor, acidity, bitterness, astringency and hardness, and decreased the regularity of alveolation and friability. Finally, the GPP fortified products achieved good sensorial acceptability.

Conclusion: GPP improved the nutritional values of fortified breadsticks and changed the rheology of dough and breadsticks' technological properties without affecting sensory acceptability. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Keywords: bakery products fortification; phenolic compounds; rheological properties; sensory analysis; winemaking by-products.

Figure 1

Breadsticks (a) and sections (b) of control breadsticks (BS0) and breadsticks fortified with 5 and 10 g 100 g⁻¹ of grape pomace powder (BS5 and BS10).

Figure 2

Sensory score of quality attributes of control breadsticks (BS0 ) and breadsticks fortified with 5 and 10 g 100 g⁻¹ of grape pomace powder (BS5 and BS10 ).