Assessing the influence of psyllium as a fat substitute in wheat and gluten-free cookies.

Psyllium is a natural fibre with high water absorption capacity and proved nutritional advantages. The aim of this study was to evaluate the potential of psyllium as a fat replacer in sugar-snap cookies. Elaborations were made with wheat flour or maize flour by maintaining the original recipe or replacing the fat by a paste made with different proportion of psyllium and water. Cookies dough rheology and final cookies properties were evaluated. An acceptability test was also carried out. The replacement of fat decreased the values of G', G″ and G*, but increased tg delta to a greater extent in cookies with gluten. Cookies diameter and spread factor decreased and increased both cookies hardness and moisture content. Fat replacement increase L* value of cookies. Variation of the water content did not influence in the rheology of the dough and in the characteristics of gluten-free cookies, but wheat cookies had smaller spread ratio and decreasing hardness for increasing amount of water. Final cookies had low acceptability and this result was more evident in gluten-free cookies. Considering this result, it is difficult to use psyllium as a total fat substitute in this type of product.