Effect of raffinose on sucrose recrystallization and textural changes in soft cookies

Sucrose recrystallization and the release of moisture that occurs as molecules of sugar are incorporated into a growing crystal lattice have been hypothesized as the cause of firming in soft cookies over time. Raffinose, a trisaccharide and known sucrose crystallization inhibitor, was tested as a means to inhibit or slow this process. Texture changes in the cookies were quantified using peak force measurements obtained by employing a puncture test. Sucrose recrystallization was successfully suppressed by the addition of 5% raffinose (w/w), as demonstrated by quantitative results obtained using powder x-ray diffraction and the degree of crystallization correlated with texture. Cookies with added raffinose were found to be significantly softer in texture, as well as having significantly decreased quantities of recrystallized sucrose. The hypothesis that sucrose recrystallization is responsible in part for the firming of cookies was shown to be logical.