Wheat flour enriched with calcium and inulin: A study of hydration and rheological properties of dough

SALINAS M.V.; ZULETA A.; RONAYNE P.; PUPPO, M.C

FOOD AND BIOPROCESS TECHNOLOGY

SPRINGER

Lugar: Berlin; Año: 2012 vol. 5 p. 3129 - 3141

1935-5130

The aim of this work was to study the effect of calcium carbonate-inulin systems on hydration and rheological properties of wheat flour dough. Wheat flour, calcium carbonate from 108 to 252 (mg Ca /100 g flour) content, and enriched inulin oligofructose at levels of 1% to 13% (flour basis), were used. Hydration dough properties were researched analyzing water absorption (Wabs), moisture content (Mcont), water activity (aw) and relaxation time (l). Wabs and aw decreased with increasing inulin levels (In) independently of calcium (Ca) content. Dough development time increased with the amount of calcium. In the presence of In, samples with the lowest content of Ca were those showing the highest development time values. Inulin was the main component that controled water absorption in dough. In the presence of CaCO3, although water seemed to be in a free state according to the high water activity value measured (> 0.975), the low value of relaxation time obtained suggests less molecular mobility. Rheological properties of dough were studied by texture, relaxation and viscoelasticity assays. Dough hardness and consistency significantly increased with calcium and mainly with inulin content. At high inulin content, dough texture was enhanced by CaCO3 due to the fact that this salt could behave as dough strengthener. Adhesiveness of dough was not modified by CaCO3 at low inulin levels. However, calcium affected adhesiveness at intermediate inulin levels. Adhesiveness was significantly increased by inulin presence. Calcium and inulin both diminished dough cohesiveness. The inulin presence increased dough elasticity, independently of calcium content.  A second-order polynomial model and response surface methodology were used for studying hydration dependence and rheological parameters (R2 > 0.771) on calcium and inulin. Dough moisture content varied with In2 and mainly inversely proportional to In. An inverse dependence of l on In was detected. Dynamic and relaxation elastic moduli (G? and E3) showed a linear dependence on In.