| 摘要 |
The present invention provides a lactic acid bacterium which has high proteolysis activity and thus has excellent peptide production ability and/or amino acid production ability. The present invention also provides fermented milk which contains an amino acid and/or a peptide at high concentration and has a good flavor. The present invention specifically provides a lactic acid bacterium belonging to the genus Lactobacillus helveticus, which is characterized by having at least one of the following properties (a)-(d). (a) The lactic acid bacterium produces 25 µmol/ml or more of a free amino acid by fermenting animal milk. (b) The lactic acid bacterium produces 8.5 mg/ml or more of a peptide by fermenting animal milk. (c) The lactic acid bacterium produces XP peptide and/or XPP peptide in a total amount of 260 µg/ml or more by fermenting animal milk. (d) The amount of IPP peptide and VPP peptide per acidity of fermented milk that is obtained by fermenting animal milk at 30-34°C (inclusive) is 6.0 mg/g or more in terms of VPP. |
