Influence of inulin–konjac suspension as a fat replacer in baked muffins and its impact on textural and oxidative stability upon storage

Abstract

In this study, vegetable oil in the muffins’ formulation was substituted with inulin–konjac (IK) suspensions (in the ratio of 70:30) at 30, 45, 60, and 75% concentration. Muffins formulated with higher IK concentrations (IK60 and IK75) showed a lower increase in hardness after storage (51% and 48%). By the end of storage, lipid peroxidation was lower in all reduced-fat muffins, with up to a 49% reduction seen in the IK30 muffin. The addition of IK suspension greatly improved the nutritional profile of the reduced-fat muffins significantly and demonstrated efficacy in delaying lipid oxidation, and starch retrogradation during prolonged storage. These findings suggest that functional muffins with reduced fat and increased dietary fiber can be produced using IK suspensions. Although the use of inulin in baked goods is well documented, there are limited studies that explore the possible use of konjac glucomannan (KGM) in baked products. Novelty impact statement Vegetable oil was substituted with a combination of inulin and konjac glucomannan. An improvement in the overall nutritional profile for reduced-fat muffins. Reduced-fat muffins showed a delay in lipid oxidation and starch retrogradation.