Gelatin-wax-based bigel System: Innovative research on a low-calorie fat substitute

In this study, we used beeswax and rice bran wax as oleogelators. We used gelatin as a hydrogelator for the hydrogels. Then, we checked the bigels' thermal, mechanical, rheological, and freeze-thaw properties with different mixes of hydrogel and oleogel. As the tests went on, it was found that when the ratio of hydrogel to oleogel was 6:4, the BG5 bigel had a water-oil bicontinuous phase. The Fourier transform infrared spectroscopy (FTIR) analysis indicated that the hydrogel and oleogel parts each had their own unique peaks. This pattern is similar to the lipid profile of butter. The storage modulus (G′) and loss modulus (G″) of the bigel changed in a way that wasn't linear as the hydrogel content went up. This indicated that the ratio of hydrogel to oleogel had a big effect on the bigel's elastic and viscous properties. Tests of freeze-thaw stability indicated that the oil holding capacity (OHC) went up significantly as the hydrogel content went up. Following three freeze-thaw cycles, the OHC values for BG2 to BG6 were 71.62 ± 1.03 %, 75.1 ± 0.36 %, 76.0 ± 0.02 %, 80.53 ± 1.85 %, and 99.60 ± 0.39 %. This study proposes a bigel preparation method with excellent structural and freeze–thaw stability, providing a new approach and technical support for the development of butter alternatives in low-fat food systems.