Fat-free whipping cream: tuning the aggregating function of living hydrophobic Lactobacillus as natural fat...

The development of non-fat whipping creams remains challenging due to the absence of fat-driven aeration and structure. Here, we demonstrate a simple salt-enabled strategy using hydrophilic Lactobacillus delbrueckii (LBD) and hydrophobic Lactobacillus crispatus (LBC) as fat replacers, with hydroxypropyl methylcellulose (HPMC) or caseinate sodium (CS) salt to regulate bacterial interfacial behavior. Salt addition significantly enhanced the foamability of CS-based formulations by 63% via promoted interfacial adsorption. Among the formulations, CS-LBC system showed the best whipping performance, achieving an overrun of 202.5% and forming uniformly distributed air bubbles (49-60 μm), resulting in a highly elastic network (tan δ = 0.21-0.26) with superior standing ability. This structure arose from Pickering stabilization by hydrophobic LBC and moderate CS-mediated bacterial aggregation. In contrast, HPMC induced excessive depletion aggregation, impairing aeration except in the more hydrophilic LBD system. Both strains maintained high viability, supporting their dual probiotic and structuring roles.