Rapid and non-targeted screening of multiple antibiotic fermentation residues in single-cell protein feed using...

Single-cell protein (SCP) feed is a sustainable protein source, yet its safety is threatened by adulteration with antibiotic fermentation residues (AFR). This study developed a rapid, non-destructive method using headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with chemometrics to screen multiple AFRs in SCP feed. Volatile profiles of nucleotide (authentic SCP), cephalosporin, and penicillin fermentation residues, along with adulterated mixtures (2-40%), were analyzed. Multivariate analyses (PCA, HCA, DD-SIMCA, OPLS-DA, PLSR) enabled pattern recognition, marker identification, and quantification. A total of 84 volatile compounds were detected. The DD-SIMCA model achieved 100% specificity, sensitivity, and accuracy, discriminating adulteration at a 2% limit. Key markers included acetic acid, butanal, and ethyl acetate, among others. PLSR models showed high predictive accuracy, with R²p of 0.99 for single-residue and 0.93 for mixed-residue quantification. This pretreatment-free approach provides a reliable tool for rapid AFR screening, enhancing feed safety and supporting sustainable SCP production.