The organism Lactococcus lactis subsp, diacetilactis converts milk citrate to diacetyl, which gives a special buttery flavor to the finished product.

乳链球菌丁二酮亚种能将乳中的柠檬酸盐转化成丁二酮，该物质会使终产品具有一种特殊的奶油香味。