The effect of preparation temperature and composition on bigel performance as fat replacers

Abstract

Consumer awareness of the deleterious effects of a diet rich in saturated fat pushes the food industry to find new fat alternatives. Bigels, hybrids of hydrogels and oleogels, are an...

Bigels as Delivery Systems: Potential Uses and Applicability in Food

“…The preparation temperature, for example, is important when incorporating thermo-labile active agents into the gels. Yet, temperature may also impact the mechanical and rheological properties and structural characteristics of the final bigel [ 32 ]. The gels can be mixed together while still molten (>70 °C, Figure 3 ), which usually results in a more homogenous distribution of phases [ 32 , 33 ].…”

“…Yet, temperature may also impact the mechanical and rheological properties and structural characteristics of the final bigel [ 32 ]. The gels can be mixed together while still molten (>70 °C, Figure 3 ), which usually results in a more homogenous distribution of phases [ 32 , 33 ]. The homogeneity could be attributed to the liquid form of both phases at high temperatures.…”

“…Microscopy is a simple characterization technique encompassing several modes with distinct suitability for analyzing different bigel types. Confocal laser scanning [ 24 , 32 , 34 , 38 , 39 , 40 , 41 ], phase contrast [ 23 ], optical [ 24 , 30 , 38 , 42 ] (including fluorescence [ 35 , 43 ] and polarized light [ 34 , 36 , 37 , 42 , 44 ]), transmission electron [ 45 ], and scanning electron [ 46 , 47 ] microscopy have been used for this purpose. All microscopy techniques provide insights into the microstructure of the bigel and, more specifically, the arrangement of the phases.…”

“…In food applications, e.g., solid fat replacers, the bigel must replicate the rheological and textural properties of the replaced fat. Pastry shortening, for example, is a key ingredient in puff pastries with a significant role in the formation of the final product’s structure through the lamination process [ 32 ]. The bigel, therefore, needs to be able to form a continuous layer on the dough, withstand high shear rates and extensional deformation, and mimic the flow behavior, firmness, and melting profile of the replaced solid fat [ 32 ].…”

“…Pastry shortening, for example, is a key ingredient in puff pastries with a significant role in the formation of the final product’s structure through the lamination process [ 32 ]. The bigel, therefore, needs to be able to form a continuous layer on the dough, withstand high shear rates and extensional deformation, and mimic the flow behavior, firmness, and melting profile of the replaced solid fat [ 32 ]. Therefore, rheological and textural testing are of great importance in screening potential bigel formulations for fat replacers and other uses.…”