The microstructure formation and rheological properties of bread containing medium-chain triacylglycerols (MCT) were investigated in comparison with long-chain triacylglycerols (LCT) and butter. Baked breads absorbed moisture in storage, and consequently water activity (aW) decreased, reaching an equilibrium after eight days; the aW of LCT bread was 0.61. In contrast, the MCT and butter breads showed aW of 0.76 and 0.72, respectively. Assessment of the rheological properties of LCT bread showed greater hardness than breads containing MCT or butter; a significant difference (p<0.05) was observed between the MCT and LCT breads. In contrast, no significant differences in the adhesion of breads were observed. With the addition of various lipids, changes were observed in the bread microstructure. With respect to the fine surface structure, a smooth surface was formed in the case of the MCT bread, as compared to that with LCT and butter. This suggests that the properties of MCT make it applicable to bread making.
Key words: Medium-Chain, triacylglycerols (MCT), long-chain triacylglycerols (LCT), microstructure formation, rheological properties, water activity.