Single‐cell rapid identification, in situ viability and vitality profiling, and genome‐based source‐tracking for probiotics products

Abstract Rapid expansion of the probiotics industry demands fast, sensitive, comprehensive, and low‐cost strategies for quality assessment. Here, we introduce a culture‐free, one‐cell‐resolution, phenome‐genome‐combined strategy called Single‐Cell Identification, Viability and Vitality tests, and Source‐tracking (SCIVVS). For each cell directly extracted from the product, the fingerprint region of D 2 O‐probed single‐cell Raman spectrum (SCRS) enables species‐level identification with 93% accuracy, based on a reference SCRS database from 21 statutory probiotic species, whereas the C–D band accurately quantifies viability, metabolic vitality plus their intercellular heterogeneity. For source‐tracking, single‐cell Raman‐activated Cell Sorting and Sequencing can proceed, producing indexed, precisely one‐cell‐based genome assemblies that can reach ~99.40% genome‐wide coverage. Finally, we validated an integrated SCIVVS workflow with automated SCRS acquisition where the whole process except sequencing takes just 5 h. As it is >20‐fold faster, >10‐time cheaper, vitality‐revealing, heterogeneity‐resolving, and automation‐prone, SCIVVS is a new technological and data framework for quality assessment of live‐cell products.