Effect of sugars on the rheological characteristics of biscuit dough and quality of biscuits

Abstract

Sugars, depending on the level and type, influenced the various rheological characteristics of biscuit dough. Increasing the sugar content from 250 to 350 g kg−1 reduced the extrusion time from 70 to 23 s, consistency from 866 to 616 N s, hardness from 814 to 512 N and apparent biaxial extensional viscosity from 2·54×105 to 1·41×105 Pa s. The development of gluten was also reduced, as indicated by a decrease in the elastic recovery from 0·515 to 0·38 mm. Spread as well as thickness of the biscuits increased with sugar level. Density as well as compression strength were reduced significantly (from 632·6 to 513·5 kg m−3 and from 118·4 to 89·2 kg, respectively) reflecting improvement in the texture. Incorporation of an additional 20 g kg−1 reducing sugars like dextrose, invert syrup, liquid glucose and high fructose corn syrup, which are normally added to improve the colour of biscuits further changed the rheological characteristics in a similar way. Among the reducing sugars, liquid glucose and invert syrup produced greater changes in rheological characteristics particularly in adhesiveness and stickiness, while high fructose corn syrup had a greater effect on the colour of biscuits. ©1997 SCI