Food texture design in sugar reduced cakes: Predicting batters rheology and physical properties of cakes from physicochemical principles

Sugar reduction in bakery products such as pound cake is a challenging task due to the multiple functionalities of sugars. Sucrose affects flour pasting behaviour, starch gelatinization and protein denaturation temperatures and batter rheology. Hence, sugar replacement can substantially alter the structure and texture of the baked product. In this study, batter rheology, phase transitions during baking and the physical properties of the baked cakes were studied as affected by 50% sugar replacement. The novelty of the study lies on relating the physical properties of batter and cakes to three physicochemical parameters computed from the cake formulations: i) the volumetric density of effective H-bonding sites available in the sugar-water phase Φw,eff; ii) the number of H-bonding sites effectively available for intermolecular interactions within the molar volume of a sugar NOH,s/vs and iii) the volume averaged interaction parameter of the sugars with water χeff. Batter rheology and phase transitions during baking showed to be a linear function of Φw,eff. Cake volume and crumb hardness were also controlled by Φw,eff. Crumb cohesiveness was a non-linear function of NOH,s/vs. The water activity of cake batters and cake crumbs were a linear function of χeff. This relations were valid with mixtures of four different types of compounds: sucrose, xylitol, an oligofructose and l-proline. In conclusion, sugar replacement in cake can be optimized by matching the physicochemical parameters Φw,eff, NOH,s/vs and χeff of the sucrose reference. Since different mixture of ingredients can be used to obtain similar physicochemical parameters, the study suggests the possibility to uncouple the physical properties of cakes from nutritional composition with regards to added sugars. Hence, the approach provides opportunities to substantially increase the amounts of health promoting ingredients such as dietary fibres in sweet bakery products.