Utilization of watermelon rind waste as a potential source of dietary fiber to improve health promoting properties and reduce glycemic index for cookie making.

Watermelon rind powder (WRP) is a rich source of dietary fiber and bioactive compounds, hence it could be used in the development of functional foods such as cookies. Different replacement levels of wheat flour with either WRP or hi-maize starch (HMS) (10-30%) on the quality of the cookies made were studied. The dietary fiber content in the cookies increased with incorporation of increasing level of either WRP or HMS. Increasing the proportion of the WRP in the cookie making resulted in an increase in the total phenolic content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, and the ferric reducing antioxidant power. Using up to 20% of WRP and 30% of HMS in the cookie making promotes: increase in dietary fiber, decrease in predicted glycemic index to medium (for WRP) and low (for HMS) levels, and improving the antioxidant activity. These changes still produce an acceptable cookie.