Understanding the role of chia ( Salvia Hispanica L.) mucilage on olive oil-based emulsion gels as a new fat substitute in emulsified meat products

This study aimed to develop a chia mucilage (MC)-based emulsion gel (EG) with olive oil to replace pork back fat in emulsified meat products. Six variables (alginate—ALG; collagen—COL; whey—WHEY; carboxymethylcellulose—CMC; transglutaminase—MTG; carrageenan—CAR) with MC were evaluated using a Plackett–Burman (PB) design. Then, a complete factorial design was applied to evaluate the interactions and properties of the selected variables (ALG, COL, and WHEY) for the manufacture of EGs. The responses evaluated in the EGs were pH, color, emulsion stability, rheological, and texture parameters. In PB, the variables CMC, COL, ALG, and WHEY did not lead to any significant effects on the pH values of EGs, which ranged from 5.6 to 5.8. WHEY had a significant effect on the increase in luminosity of the EGs. ALG and WHEY decreased the liquid release of the samples showing greater stability of EGs and meat model systems. All samples of EGs, apart from run 5 (CMC, MTG, CAR, and ALG), showed a typical gel-like behavior ( G ʹ > Gʺ ) and a frequency-independent behavior. Even the formulation with only mucilage (run 12) showed a dominant G ʹ forming a gel-like structure. The complete factorial design showed stable and strong interactions between WHEY, MC, and olive oil, since a small or no liquid release, were observed in all experiments with WHEY. This study contributed to understanding the interactions among MC, biopolymers, and proteins, disclosing the potentiality of chia mucilage-based emulsion gels for the replacement of animal fat in emulsified meat products. Graphic abstract