Development And Quality Analysis Of Grifola Frondosa Crabapple Fermented Beverage

Grifola frondosa is rich in nutritional value and has a variety of biological activity,but its commercially available products related have few types and poor flavors.Crabapple is a kind of apple tree fruit,which is often used to develop fruit wine,fermented beverage and other products.Based on the previous research in the laboratory,Lactobacillus plantarum CGMCC3005,Lactobacillus bulgaricus CGMCC15159 and Streptococcus thermophilus CGMCC15160 were selected as fermentation agents.Through optimized fermentation process,a Grifola frondosa crabapple fermented beverage with superb taste was developed.The main results were as follows:(1)Taking Grifola frondosa and crabapple as raw materials,the single factor experiment and orthogonal experiment were used to detect the fermentation conditions of the beverage.Finally,the optimum process conditions were determined as follows:the extract of Grifola frondosa and crabapple were mixed 1:1;the addition amount of granulated sugar was 6%;the fermentation lasted 3 days;the strain ratio of CGMCC3005:CGMCC15159:CGMCC15160 was 2:1:1;The fermentation temperature was 37℃.Under these conditions,the beverage is of mellow flavor,being sweet with sour taste.(2)In this experiment,electronic nose,gas chromatography/mass spectrometry(GC/MS)and electronic tongue were used to study the changes of flavor during the fermentation of the beverage.The results indicated that lactic acid bacteria fermentation could promote the diversity of volatile compounds in the beverage,improve the original bad flavor of Grifola frondosa,increase the content of fresh and sour substances,and reduce the content of bitter substances.Furthermore,the original 1-neoene-3-alcohol,1,2,3,5,6-pentathioheterocyclic heptane and other characteristic flavors of Grifola frondosa were retained.Therefore,lactic acid bacteria fermentation was an effective method to improve the sensory characteristics of Grifola frondosa crabapple beverage.(3)In this experiment,the changes of short chain fatty acids,organic acids,sugar content and soluble protein during the fermentation of Grifola frondosa and crabapple beverage were studied by chromatography and Bradford method.The results showed that the content of soluble protein was 0.35±0.02 mg/m L after 3 days of fermentation;The content of acetic acid was the highest with 15.50±0.94μg/m L;The contents of lactic acid,succinic acid and adipic acid increased;In addition,lactic acid bacteria could decompose sucrose into glucose and fructose,which were then metabolized and utilized by lactic acid bacteria.(4)The results showed that after 3 days of fermentation,the beverage was rich in polyphenols and flavonoids,and had favorable antioxidant activity.(5)The long-term stability test was used to detect the shelf life of the fermented beverage.The results showed that the fermented beverage could maintain good color and taste at 4℃ for 35 days,and viable count of the beverage remained above 10~6CFU/m L.Therefore,a fermented beverage with good flavor and antioxidant activity can be prepared by using lactic acid bacteria to ferment the fruit and vegetable juice of Grifola frondosa and crabapple.