Abstract
The effects of two commercial emulsifiers (sucrose esters of fatty acids with C16 and C18 fatty acid moieties) on the growth, germination and/or outgrowth of six strains of the causative bacteria of O. A. flat sour spoilage were studied.
In the TSiF medium, both emulsifiers at concentrations higher than 100ppm inhibited the growth of all six strains. For germination and/or outgrowth, the minimal inhibitory concentration (MIC) of one of the emulsifiers was 10ppm and that of the other was 10 to 100ppm depending on the strain.
In the coffee medium, the highest MIC of both emulsifiers for growth, germination and/or outgrowth was 300ppm. In the shiruko medium, the highest MIC of one of the emulsifiers for growth was 5000ppm and that of the other was 6000ppm. The highest MIC of both emulsifiers for germination and/or outgrowth was 5000ppm.
It is concluded that the sucrose esters can prevent O. A. flat sour spoilage at 300ppm in canned coffee and at 5000ppm in canned shiruko. It is suggested that the addition of the sucrose esters would effectively prevent the spoilage of canned drinks kept hot in vending machines in Japan.
