Novel Fat Replacers Based on Pork Lard and a Cold Gelling System in the Reformulation of Reduced-Fat Fresh Pork Sausages Containing Silicon from Diatomaceous Earth Powder

This study examines the effects of an emulsion gel (EG) and a fat bulking agent (BA), both formulated with pork lard (PL) and an alginate-based gelling system, as animal fat replacers in the reformulation of reduced-fat fresh pork sausages. Both fat analogs were characterized in terms of texture, color, and in vitro gastrointestinal digestion (GID) before being used in the reformulation of four fresh pork sausages, without and with added silicon (Si) from diatomaceous earth powder: S/EG, S/EG-Si, S/BA, and S/BA-Si. Reduced-fat sausages elaborated exclusively with pork backfat (PB), without and with Si, were used as controls (S/C and S/C-Si). Both EG and BA showed adequate physicochemical characteristics and slowed in vitro GID compared to PL and PB. Replacing 75% PB with EG or BA did not negatively impact the technological, nutritional, or sensory properties of the reformulated pork sausages, which were kept for 14 days under refrigeration. Additionally, sausages containing EG or BA as fat substitutes presented lower lipid digestibility after in vitro digestion compared to the control samples. The addition of Si further limited fat digestion, as reflected by the lower release of free fatty acids after in vitro GID compared to products without added Si. This effect was more pronounced in EG-based formulations. Therefore, the use of EG as a PB replacer, together with the addition of Si, could become a promising strategy for developing healthier meat products. This finding may have important implications for the development of functional meat products aimed at reducing fat content and lipid absorption, thereby laying the foundation for precision nutrition strategies focused on improving individual health outcomes.