摘要 |
PROBLEM TO BE SOLVED: To obtain beverage or food products in a low cost, containing γ- aminobutyric acid useful for improving hypertension and the like with excellent taste and color tone by inoculating a microorganism capable of producing protease to a specific food material and culturing it. SOLUTION: A food material that contains the peptide or protein including glutamic acid as a constituent amino acid, for example, powdered skim milk, soybean milk and the like is inoculated with a microorganism capable of producing protease, for example, a lactic acid bacterium that can liberate >=0.5 wt.% of glutamic acid after subtraction of its assimilated fraction based on the protein, when it is cultured in a 20% powdered skim milk substrate at 25-40 deg.C for 2 days and with a microorganism capable of producing glutamate decarboxylase, for example, a bacterium in Bifidobacterium, capable of producing >=600 mg/100 ml of γ-aminobutyric acid, when it is cultured in a culture medium containing 1,000 mg/100 ml of glutamic acid (glutamate salt) at 25-40 deg.C whereby the objective γ-aminobutyric acid-containing beverage or food products are obtained. |