Exploiting biphasic gel system to design new architectures for alternative foods

Biphasic gel systems which combine oleogel phase and hydrogel phase, termed bigels, offer a promising alternative to solid fats, reducing overall fat content while maintaining sensory quality. Such materials can be exploited for other alternative applications such as meat and dairy replacers by incorporating plant-protein based hydrogel. Current research explores the use of plant-protein based hydrogel in bigel formulation aiming to produce new materials with unique texture and nutritional values. Bigels were produced using candelilla wax oleogel combined with canola-protein or pea protein hydrogel where the ratio between the phases and the protein concentration were examined. Overall, higher protein content and oleogel ratio produced harder gels with moderate viscoelastic behavior. The effect of transglutaminase, an enzyme able to catalyze the formation of covalent cross-links between amino acids residues in proteins, was examined. It was found that TG is a crucial element to produce a stable and consistent bigel while using canola protein. Higher TG concentration resulted in stronger gels and thermal resistance, demonstrated by increased hardness and storage modulus values and softening behavior during thermal treatment. The addition of salt, a common additive in dairy products, was also examined. It seems that even low concentration of salt was able to significantly change the bigel texture transforming from brittle to consistent texture. This behavior was correlated to the electrostatic hinderance of the salt at the water-oil interface which affects total gel behavior as seen in microstructure analysis. The results provide in-depth understanding regarding the factors affecting plant-based bigel properties aiming to rationally design new solutions for alternative products.