Incorporation of Himanthalia Elongata Seaweed to Enhance the Phytochemical Content of Breadsticks Using Response Surface Methodology (RSM)

Optimization of incorporating seaweed into breadsticks was carried out using response surface methodology (RSM). Ten formulations of breadsticks were processed by varying concentrations of seaweed (X ₁ = 5 to 15% of overall flour concentration) and white flour (X ₂ = 10 to 30% of overall flour concentration) using a central composite design. The remaining flour concentrations were comprised of wholemeal flour. Predicted models were found to be significant (P < 0.05) for total phenolic content (TPC), DPPH radical scavenging activity, texture and color. Predicted values for each of the responses were in good agreement with the experimental values. Seaweed concentration had most significant effect on phytochemical constituents of the breadsticks with TPC and DPPH activity maximized when 17.07% H. elongata was incorporated into the flour (P < 0.05). An acceptable edible texture and color of breadsticks was also achieved at this concentration. Multiple response optimization demonstrated that phytochemical content of H. elongata breadsticks may be maximized with dried seaweed and white flour concentrations of 17.07 and 21.89%, respectively, in the total flour. Total dietary fiber increased from 4.65 to 7.95% in the optimized sample, representing a 43.65% increase as compared to the control (P < 0.05). A sensory panelevaluated the acceptability of the seaweed breadsticks, as compared to the control, in terms of aroma, color, texture, taste and overall acceptability. There was no significant difference (P > 0.05) between the seaweed breadsticks and the control which shows that such fiber-rich seaweed bakery products are acceptable to consumers and have potential of increasing seaweed consumption among non-seaweed consumers.