A novel method for increasing the rate of starter lysis during Cheddar cheese ripening has been developed, using a bacteriocin-producing strain as a starter adjunct. Citrate-utilizing Lactococcus lactis ssp. Lactis DPC3286 encodes production of lactococcins A, B, and M and exhibits a lytic effect against lactococcal starter cultures. Cheddar cheese was manufactured using DPC3286 as an adjunct with the cheese-making strain Lactococcus Lactis ssp. cremoris HP. The effects on starter cell lysis;, proteolysis, and flavor development were assessed over a 60-mo period. Cheese manufactured with the bacteriocin-producing adjunct exhibited increased cell lysis, elevated concentrations of free amino acids, and higher sensory evaluation scores than cheese manufactured with HP alone or with an adjunct culture negative for bacteriocin production.