Abstract:Using the starter containing six probiotics mixed with equivalent ratio，banana puree，sweet potato pulp and fructooligosaccharide were added to prepare for the fruit and vegetable milk beverage possessing the function of embellishing aperient bowel.The fermentation conditions were optimized by single factor experiments and response surface methodology according to the acidity，living bacteria and antimicrobial activity.The culture conditions were optimized as followed：using the treated whey powder and skimmed milk（containing 5%whey powder and 3%skim milk powder） as the substrate， banana puree， sweet potato pulp and fructooligosaccharide were separately added 15.67%，10.44%and 2.23%and fermented for 24 h under 38℃.With these conditions satisfied，the living bacteria were reached to 9.58 lgCFU/mL，and the inhibition zone diameters to Escherichia coli，Staphyloccocus aureus，Bacillus subtilis and Pseudomonas brenneri were 23.04，19.43，21.11 mm and 18.23 mm，separately.Furthermore，the acidity，living bacteria and antimicrobial activity of the beverage during the storage were estimated.Considering the absolute superiority of the sensory quality and the living bacteria，the beverage was recommended to be drunk within 21 days.