Short communication: Change of naturally occurring benzoic acid during skim milk fermentation by commercial cheese starters

This study sought to investigate the change of naturally occurring benzoic acid (BA) during skim milk fermentation by 4 kinds of commercial cheese starters used in domestic cheese. The culture was incubated at 3-h intervals for 24 h at 30, 35, and 40°C. The BA content during fermentation by Streptococcus thermophilus STB-01 was detected after 12 h at all temperatures, sharply increasing at 30°C. In Lactobacillus paracasei LC431, BA was detected after 9 h at all temperatures, sharply increasing until 18 h and decreasing after 18 h at 30 and 35°C. In the case of R707 (consisting of Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris), BA increased from 6 h to 15 h and decreased after 15 h at 40°C. The BA during STB-01 and CHN-11 (1:1; mixture of S. thermophilus, Lc. lactis ssp. lactis, Lc. lactis ssp. cremoris, Lc. lactis ssp. diacetylactis, Leuconostoc mesenteroides ssp. cremoris) fermentation was detected after 3 h at 35 and 40°C, sharply increasing up to 12 h and decreasing after 15 h at 35°C, and after 6 h, increasing up to 9 h at 30°C. After 3 h, it steadily decreased at 40°C. The highest amount of BA was found during the fermentation by R707 at 30°C; 15 h with 12.46 mg/kg.