Diacetyl is formed by fermentation of citrate by Lactococcus lactis ssp. lactis biovar diacetylactis and Leuconostoc adjunct cultures during manufacture and aging of some cheeses giving them a buttery flavor. Several lactic acid bacteria isolates were screened for their ability to ferment citrate to diacetyl in M17 lactose broth supplemented with 0.5% citrate, with 6 strains growing and producing diacetyl up to 5% salt. Two of the Lc. lactis ssp. lactis biovar diacetylactis strains (LD2 and SD5) were then studied further (in duplicate) in M17 broth with salt concentrations up to 9%. Diacetyl concentration was measured colorimetrically using the Vasavada and White method involving reaction with naphthol and creatine, then measuring absorbance at 540 nm. After 48 h incubation at 30°C, LD2 produced from 6.1 to 9.6 μg/mL of diacetyl with no significant difference up to 5% salt, with decreased amounts (only 1 to 2 μg/mL) at 6% to 8% NaCl. For SD5, the highest level (19.9 μg/mL) was produced with 1% salt, slowly decreasing to 10.2 μg/mL at 5% salt, and then dropping to 5.4 to 5.6 μg/mL at 6 to 8% salt. A similar pattern was observed when a mixture of LD2 and SD5 was used. Cheese was then made using 113 kg of milk (in duplicate) using a Lactococcus lactis starter culture with a combination of SD5 and LD2 added as adjunct cultures. Whey was drained at pH 6.45 and then the curd dry stirred until reaching pH 5.6, divided into 3 portions and then adding 15, 20 or 30 g/kg of salt. The cheese was then pressed and stored at 6°C. Salting promoted whey expulsion and also retarded further acidification of the curd. For the low, medium and high salt levels, cheese pH was 5.27, 5.38 and 5.42, average moisture was 42.2, 41.5 and 40.8%, and average salt content was 1.0, 1.5 and 1.7%, respectively. Average salt-in-moisture contents were 2.4, 3.5 and 3.9%, respectively. After 2 weeks of storage, all of the cheeses contained 6 to 7 μg/g of diacetyl. In conclusion, use of Lc. lactis ssp. lactis biovar diacetylactis strains that are relatively salt tolerant for diacetyl production in cheese made using a stirred curd does not appear limited because of the direct mixing of curd with salt rather than using a brining method.