Studies On The Characteristics Of Taste Of Lentinula Edodes?Flammulina Velutipes And Extract Non-Volatile Taste Components

Edible fungi was widely accepted and loved because of its special delicious flavor.In this study,we use Flammulina velutipes and stem of Lentinula edodes(Shiitake mushroom)as the research object.And study the influence of extraction of the non-volatile taste components from two kinds of edible fungi by different methods.Therefore,we can confirm the best technological parameter of extraction methods and determination the non-volatile taste components of different hydrolysates by HPLC and Automatic amino acid analyze.Futher Evaluation of the flavor properties of different hydrolysates by E-tongue and sensory evaluation will be made.As a result we can study the influence of flavor properties by different approaches and accumulate a certain theoretical basis for further development of the corresponding seasoning.Research are mainly based on several following parts:1.Confirmation of the best technological parameter of extraction by ultrasonic or microwaveOptimum parameters of ultrasonic assisted extraction are: the Flammulina velutipes:ultrasonic power: 350 w,Solid-liquid ratio: 1:20,time: 5 min;stem of Shiitake: ultrasonic power: 450 w;Solid-liquid ratio: 1:30;time: 3 min.Optimum parameters of microwave assisted extraction are: the Flammulina velutipes: microwave power: 150 w;Solid-liquid ratio:1:20;time: 3 min;stem of Shiitake: microwave power: 150 w;Solid-liquid ratio: 1:40;time: 3min.Based on the results we find that Microwave extraction is more effective than ultrasonic extraction of free amino nitrogen.The result of amino acid determination also show that the extraction rate of microwave method is higher.Under the optimum parameters the extraction yield of non-volatile taste components is,Flammulina velutipes: free amino acid 5.12 mg/g,5'-nucleotide 4.45 mg/g,soluble sugar,107.98 mg/g,organic acid 53.92 mg;stem of Shiitake mushroom: free amino acid 2.53 mg/g,5 '-nucleotide 10.42 mg/g,soluble sugar,80.70mg/g,organic acid 25.52 mg.2.Protease screening and evaluation the flavor properties of hydrolysatesWe build a panel consists of 11 panelists who run the evaluation the flavor properties of hydrolysates based on basic taste and perceptual measure.The result of sensory evaluation we found that except several samples of the twelve hydrolysates have obvious differences in taste.The common characteristics of two types of hydrolysate are umami.The PCA results of E-tongue show that hydrolysates of Flammulina velutipes: pc1 + pc2 = 96.888 %;hydrolysates of stem of hiitake: pc1 + pc2 = 93.847 %,Which indicate accurate reflection of the raw data.In combination with the results of CA,we can distinguish every hydrolysates effectively.By selecting a representative sample of protease based on integrating the result of E-tongue and sensory evaluation,The results show Flammulina velutipes treated with Trypsin or Flavourzyme,stem of Shiitake mushroom treated with compound proteinase show typical non-volatile properties differences.The results of amino acid determination show that a greater difference between different hydrolysates of amino acid content.The concentration range of non-volatile taste components in various hydrolysates are: Flammulina velutipes,free amino acid 0.77-2.01 mg/ml,taste nucleotide 0.31-0.41 mg/ml 0.79-1.28 mg/ml,soluble sugar,3.43-5.93 mg/ml,organic acid;stem of Shiitake mushroom: free amino acid 0.89-1.80mg/ml,flavor nucleotide 0.11-0.18 mg/ml soluble sugar,0.43 1.8 mg/ml,organic acids,0.92-1.70 mg/ml.3.Enzymolysis edible fungi after Microwave processingThe hydrolysates of edible fungi by microwave pretreatment are quite similar in flavor properties.The results of E-tongue and sensory evaluation show that they're difficult to be discriminated.The determinations of flavor component display two kinds of hydrolysate on the similarity between the flavor component content.Free amino acid contents are reduced than processing without microwave pretreatment,the concentration of free amino acid are:Flammulina velutipes: 0.24 mg/ml?0.28 mg/ml;stem of Shiitake mushroom: 0.13 mg/ml?0.14 mg/ml.It's possibly that the microwave pretreatment causes samples to form some special protein spatial structure which is disadvantageous for enzymolysis.