Effect of components and heating on rheological properties of custard

Custard has been used worldwide in various confectionery and other food due to its characteristic viscoelasticity. However, the main ingredients of custard are wheat flour, egg, and milk. These ingredients contain allergens, and demands are increasing to substitute these ingredients in custard with non-allergenic alternatives. Therefore, in this study, we prepared several standard custards comprising commercial ingredients and model custards constituted using elementary compounds according to a general recipe for custard. We then investigated the effect of the various ingredients and heating on the rheological properties of these custards. Polysaccharides, e.g., starch, and disaccharides, e.g., sucrose and lactose, synergistically enhanced the rheological property like the consistency index. The disaccharides not only sweetened the custard but were also responsible for the texture of custard following heating, based on our analysis of the custards' thixotropic properties. We anticipate these findings will be useful for producing a novel custard with potentially allergenic ingredients substituted by non-allergenic ingredients in the future.