INVESTIGATING THE EFFECTS OF PROMOAT BETAGLUCAN ON IMPROVING AND MAINTAINING THE DESIRED STRUCTURE AND PHYSICAL PROPERTIES OF SPONGE CAKES OVER TWO WEEKS OF STORAGE.

Abstract: This project investigated the impact of beta-glucan on sponge cake's desired texture and physical properties. Sponge cakes with different percentages of Lantmännens PromOat beta-glucan (0.0%, 1.0% and 2.0%) were produced and compared on the following parameters: volume, density, water activity, moisture content and texture profile analyses. These parameters were measured on different storage days (1, 3, 7, 10 and 14) to evaluate structural changes over time. Matlab's ANOVA and multivariate PCA analysis were used for data analysis. The results revealed significant treatment, batch and storage influences on cake characteristics. The beta-glucan percentage increased hardness, gumminess, moisture content, water activity and density, and it decreased the cake's volume, cohesiveness and springiness. Storage time was found to influence hardness, chewiness and gumminess the most. Contrary to previous research, increased beta-glucan levels led to a decrease in volume and springiness and an increase in density and cohesiveness, probably due to the formation of smaller air bubbles and hindered expansion. However, cakes with 2.0% PromOat beta-glucan unexpectedly increased in springiness. Moisture content and water activity increased with increasing beta-glucan percentages due to its water-absorbing properties. Nevertheless, cakes fortified with PromOat beta-glucan showed a greater decrease in moisture content, probably related to the increasing hardness. Hardness, chewiness and gumminess increased with increasing storage time, in which cakes with 2.0% PromOat beta-glucan had the highest values. These changes were likely related to retrogradation, ingredient composition and reduced moisture content. Furthermore, unlikely batch variations were observed, pointing out the importance of maintaining batch consistency in future research. In conclusion, this research provided insights into the effects of different beta-glucan percentages on structural and physical factors over a two-week storage period. Complex interactions between beta-glucan, storage time, ingredients and cake characteristics were presented. Further research is needed to investigate these interactions and demonstrate the optimal use of beta-glucan levels in sponge cakes.