Influence of sugar replacers on the mechanical and rheological properties of doughs for sweet baked goods

Sweeteners are important ingredients in bakery products. Besides providing a sweet taste, they also affect fermentability, appearance, flavor, dimensions, color, and texture of the finished products. There are many available choices of sweeteners, and the type chosen depends on the functions to be performed and on the desired level of sweetness, appearance and texture of the baked product. As regards human diet, sugars play a double role: they are a fundamental energetic source, but their excessive intake has been often connected to short- and long-term pathologies. Therefore, food industries express a growing interest in sucrose substitutes to be used in low-sugar products. However, when the sugar content is changed, food rheology and texture may be negatively affected. Even if often considered secondary, and thus little investigated, these aspects have a fundamental importance, since a novel food adequately formulated from a nutritional and healthy point of view should also be pleasant and satisfactory at consumption. Thus, the aim of this study was the evaluation of the effects of the presence of different sweeteners on the mechanical and rheological properties of doughs for sweet baked goods. Different “croissant-type” formulations without sweeteners or containing, as alternatives, sucrose, fructose, or sucralose were investigated. The structure of the dough was evaluated by means of different techniques able to describe the intrinsic properties of the material and to predict its behavior in a real process. Both empirical (farinographic test, dynamometric measurements) and fundamental rheological tests (dynamic oscillatory measurements) were performed. Generally, the doughs containing sucralose showed mechanical and rheological properties very similar to those of the doughs produced with no added sugars: they resulted to be firmer, more resistant to tensile forces and less viscous than the dough containing sucrose or fructose. It came out how the use of alternative sweeteners, and of a high-intensity sweetener in particular, have to face with the technological challenge of a complete substitution of sucrose properties. This is the reason why frequently other ingredients (e.g. bulking agents) should have to be added to low-sugar baked goods to compensate sucrose functionalities complementary to sweetening.