Effects Of Lactobacillus Plantarum And Inoculation Method On Malolactic Fermentation And Sensory Quality Of Blueberry Wine

Chinese blueberry wine industry is developing rapidly and has great potential.However,the color of blueberry wine is unstable and easy to fade.There is a lack of relevant basic research at present.Previous research has shown that Lactobacillus plantarum could be used for fruit wine malolactic fermentation to improve the sensory quality of product.In this study,L.plantarum suitable for consumption of malic acid in blueberry juice were isolated and screened,then the effects of strains and inoculation method on malolactic fermentation of blueberry wine were compared.The influence of the best inoculation model of L.plantarum on the sensory quality of blueberry wine was explored through sensory evaluation,typical chemical and physical analysis,GC-MS,and UHPLC-MS/MS.The main results were as follows:1.30 acid-producing gram-positive strains were isolated from naturally fermented blueberry juice,and 4 of them were identified as L.plantarum.Then these 4 strains and 13 strains of L.plantarum isolated from other materials were inoculated into blueberry juice.B3,B4,LP39 and SS6 with strong capacity of consuming malic acid and great difference in color influence were screened out for further study.2.Sequential inoculation could not accomplish malolactic fermentation in blueberry wine.When use the method of reverse inoculation which is inoculate L.plantarum first and then yeast,the comsuming of malic acid were depended on the p H of the blueberry juice.When p H less than 3.0,L.plantarum could not survive,while p H higher than 3.0,L.plantarum could survive and the malic acids could be completely consumed.In all,reverse inoculation was the most suitable method for malolactic fermentation of blueberry wine.3.Reverse inoculation of 4 trains of L.plantarum which were screened out before can complish malolactic fermentation well.Flash profile results showed that reverse inoculation of L.plantarum significantly affected the organoleptic quality of blueberry wine:the chroma and tone of B3 and Red fruit~?(not inoculated with L.plantarum)treatment were found better than other treatment.The sourness of B3 and B4 treatment was found more prominent.Tasting members were found having different understanding on the blueberry aroma.4.A total of 138 volatiles and 45 anthocyanins were qualitatively and quantitatively from blueberry wine samples.Cluster analysis and partial least squares regression analysis showed that reverse inoculation of L.plantarum was beneficial to the anthocyanin derivation and the formation of volatiles.In addition,the compositon of volatiles and anthocyanins were different in samples inoculated with different strains.In conclusion,this study indicated that the reverse inoculation of L.plantarum could be a suitable method for the malolactic fermentation of blueberry wine.And strains had different effects on the sensory quality of blueberry wine.This study might provide new knowledge for improving the quality of blueberry wine.