Anthocyanin-rich sweet potato lacto-pickle: production, nutritional and proximate composition

Anthocyanin pigment-rich sweet potato (SP) cubes were pickled by lactic fermentation by brining the cut and blanched cubes in common salt (NaCl, 2-10%) solution. They were then inoculated with a strain of Lactobacillus plantarum (MTCC 1407) and incubated for 28 days. Treatment with 8-10% brine solution was found to be organoleptically most acceptable. The final product with 8% and 10% brine solutions had a pH (2.5-2.8), titratable acidity (TA) (1.5-1.7 g kg⁻¹), lactic acid (LA) (1.0-1.3 g kg⁻¹), starch (56-58 g kg⁻¹) and anthocyanin content (390 mg kg⁻¹) on fresh weight basis. Sensory evaluation rated the anthocyanin-rich SP lacto-pickle acceptable based on texture, taste, aroma, flavour and after taste. Principal component analyses reduced the eleven original analytical and proximate variables (pH, TA, LA, starch, total sugar, anthocyanin, organic mater, ash, fat, protein and calories) to three independent components (factors), which accounted for 91% of the total variations.