Preparation of a bigel system based on k-carrageenan hydrogel and beeswax oleogel and the effect of starch on the bigel properties

Abstract

This study utilized beeswax and k-carrageenan as gelling agents to prepare oleogels and hydrogels, respectively. The amalgamation of the two gels in frozen water led to the formation of bigels. With the goal to improve the consistency and long-lasting nature of the bigel, starch was added to the mixture. A study was then done to evaluate how the addition of starch affected the thermal, mechanical, and rheological properties, as well as the capacity of the bigel to withstand freeze-thaw resilience. The results indicated that the bigel without starch exhibited a melting temperature comparable to that of the oleogel. However, the inclusion of starch resulted in a decrease in the melting temperature to 44.88 °C, accompanied by a wider endothermic peak. The enthalpy of the bigel with additional starch dramatically increased to 42.227 J/g. The addition of starch significantly improved the mechanical characteristics of the bigel, resulting in an average increase in hardness of 32.3% and Young's modulus of 54.2%. Furthermore, the bigel demonstrated exceptional freeze-thaw stability, exhibiting an average enhancement of around 5% when compared to the equivalent without starch. The use of hydrogel enhanced the thermal durability of the bigel, preventing structural collapse when the ambient temperature rose. This study proposes a method to produce starch bigels that possess excellent freeze-thaw stability and rheological properties.