FERMENTATION OF LYE-TREATED CARROTS BY LACTOBACILLUS-PLANTARUM

Sodium hydroxide treatment of peeled and trimmed carrots was investigated to rid them of natural epiphytic microflora that interferes with fermentation. It also formed a buffered brine by subsequent neutralization with acetic acid. Two lye concentrations (1% and 2% NaOH) and three treatment times (1, 15 and 30 min) were evaluated. Inoculation of Lactobacillus plantarum into NaOH-treated carrot brines resulted in a controlled fermentation yielding lactic acid almost exclusively. Percent carbon recovery varied from 83.7 to 148.3. More than 92% of available glucose and >85% fructose, but <13% sucrose, were utilised after 7 days fermentation. Texture and surface color (L*) of fermented NaOH-treated carrots were affected (p < 0.05) by NaOH concentration and treatment time. The product flavor was not adversely affected by alkaline treatment.