Stabilization fate of bovine bone high-temperature hydrolysate emulsion: An interfacial perspective induced by NaCl

Bovine bone high-temperature hydrolysate (BBHH) is the main raw material that is used to prepare emulsified products including sauce packets, beef bone broth and bovine bone white soup. These traditional foods are favored by consumers for their unique nutritional value and sensory quality in Asia. However, as an emulsifier, BBHH alone has limited emulsification and stabilization capacity.

This study investigated how NaCl affects the stability of BBHH emulsion by influencing the adsorption properties, microstructure and physicochemical interactions. The adsorption rate (34.65 ± 2.05%) and thickness of the adsorbed layer (100.55 ± 0.45 nm) were the highest at 100 mm NaCl. The cross-linking of oil droplets was enhanced at 100 mm NaCl, whereas the fine network of emulsion was damaged with excessive NaCl concentration (200 mm) observed by cryo-scanning electron microscopy. Raman spectroscopy confirmed that the unfolding of the interfacial protein and strengthening oil-protein interactions increased emulsification. Moreover, BBHH emulsions showed different emulsifying stability by NaCl induction, such that the emulsifying stability index values were 78.09 ± 1.21% at 100 mm NaCl and 68.91 ± 0.35% at 200 mm, which could be elucidated by the interfacial properties, indicating that the interfacial properties were essential for the emulsions.

The present study demonstrated that BBHH emulsion exhibited good stability at lower ionic strength (≤ 100 mm NaCl). These discoveries provide valuable insights into the relationship between emulsion stability and interfacial properties, as well as contribute to a further understanding of NaCl induction in the food industry. © 2025 Society of Chemical Industry.