Flavour formation in Cheddar cheese occurs mainly in the ripening stage and results from enzymatic breakdown of carbohydrates, fats and proteins by non-starter lactic acid bacteria. Cheese ripening can be a lengthy and costly process, taking up to two years for vintage Cheddar cheese. Therefore, acceleration of cheese ripening has attracted significant research interest. Addition of adjunct cultures, in particular Lactobacillus, has been shown to reduce maturation time and/or improve flavour. The current study aims to develop a fast screening method in a simple cheese model to select for potential flavour adjuncts based on detection of odour-active, volatile compounds associated with desirable Cheddar cheese flavours. Candidate adjunct strains, mostly Lactobacillus, were inoculated into UHT milk at 10⁵-10⁶ CFU/mL in conjunction with a two-strain mix of Lactococcus lactis starter at 10⁷ CFU/mL and incubated at 30°C for 7 days. On day 7, the candidate adjuncts grew to 10⁷ - 10⁸ CFU/mL, while starter counts dropped below 10² CFU/mL. Volatile compounds in the 7-day fermented curds were detected by headspace solid phase microextraction gas chromatography-mass spectrometry, and the flavour profiles obtained were compared to those from Cheddar cheese. Volatile compounds that are characteristic of Cheddar flavour were found, including 3-methylbutanal, diacetyl, dimethyl disulphide, acetic acid, butanoic acid, hexanoic acid and octanoic acid. The abundance of aroma compounds varied significantly by species, e.g. Lactobacillus rhamnosus and Lactobacillus helveticus strains were associated with higher concentrations of diacetyl and 3-methylbutanal respectively, while Lactococcus lactis subsp. cremoris strains produced less acetic acid and short-chain fatty acids. Promising adjunct strains will be used in pilot-scale cheesemaking and the cheese subjected to sensory analysis. Strains that produce cheese with desirable flavours, ideally also requiring shorter ripening times, will be selected for genomic sequencing to determine the genetic features and metabolic pathways associated with positive flavour properties.