FLAVOR DEVELOPMENT IN ASEPTIC CHEESE CURD SLURRIES PREPARED WITH SINGLE-STRAIN STARTER BACTERIA IN THE PRESENCE AND ABSENCE OF ADJUNCTS

Eight strains of Lactococcus starter bacteria were tested under microb iologically controlled conditions for their ability to produce Cheddar cheese flavour. For this purpose, aseptic Cheddar cheese curds were p repared with each of the organisms, and the resulting curds slurried w ith sterile salt and water, and stored at 30 degrees C for accelerated flavour development. Distinct though weak Cheddar cheese flavour was produced by the Lactococcus lactis subsp cremoris strain SK11, but not by strains ASCC457, ASCC50, ASCC109, ASCC660, ASCC360, or the L lacti s subsp lactis strain ASCC381, or the L lactis subsp lactis biovar dia cetylactis strain ASCC250. Different starter strains produced differen t degrees of bitterness, with strains ASCC457, 109 and 660 producing t he most bitter slurries. Strains SK11, ASCC50, ASCC360, and ASCC250 pr oduced only slight bitterness in slurries ripened for 15 days. Free fa tty acid concentrations in the slurries differed depending on the star ter strain used, implying that different starter strains have differen t lipase activity. Cheese flavour development was slow in the slurries containing only starter bacteria. In contrast, slurries made with the strain SK1I in the presence of the adjuncts Lactobacillus helveticus ASCC395, Brevibacterium linens CSCC750 or Lactobacillus casei subsp ca sei NCDO151 underwent rapid flavour development, giving distinct and s trong cheese (but not Cheddar) flavours for each adjunct. These differ ences in flavour, however, could not be explained in terms of differen ces in the non-sulphur volatile composition of the slurries determined by static headspace analysis.