Extraction And Properties Of The Lentinus Edodes Stem Protein And The Application Of New Nutritious Bread's Development

Lentinus edodes is a high-quality edible fungus that is popular among people for both medicine and edible value.According to research reports,Lentinus edodes have high protein and fiber contents and low fat content,which is a natural food for human health.Mushroom stem is usually removed first during the processing of mushroom.As a matter of fact,the Lentinus edodes stem is comparable in nutritional value to the Lentinus edodes pileus.The Lentinus edodes stem is rich in proteins(20%),which can be used as a good source for obtaining new high-quality protein.Therefore,in this project,the dried Lentinus edodes stem was used as raw material to study the extraction process of protein,and its physicochemical properties and functional properties.The Lentinus edodes protein is then applied to bread making to develop a new type of nutritious bread.Firstly,the extraction process of alkali extraction and acid precipitation of Lentinus edodes was studied.The effects of feed-liquid ratio,pH,temperature and extraction time on the protein extraction rate were analyzed.The optimized process conditions obtained by response surface experiment were: material-liquid ratio 1:45,pH 10.0,temperature 50°C.When extracted under the conditions of the preparation for 3 h,the extraction rate of the protein was 33.59%,and the protein yield was8.93%.Secondly,the physicochemical properties and functional properties of Lentinus edodes were studied.Thermal stability analysis showed that the heat denaturation temperature of Lentinus edodes protein was 77.87°C,and the enthusiasm is 94.90J/g The surface hydrophobicity analysis showed that the number of hydrophobic residues on the surface of the Lentinus edodes protein molecule was smaller than that of the bean isolate and casein.The results of the thiol assay indicated that the sulfhydryl groups in the Lentinus edodes protein molecule were mainly present in a free state.It was found by circular dichroism and Fourier transform infrared spectroscopy that the secondary structure of Lentinus edodes was mainly ?-turn.The results of functionalproperties showed that the solubility,water absorption,oil absorption and emulsifying properties of Lentinus edodes were better than that of soy protein isolate and casein.The foaming ability was comparable to that of soybean protein isolate,and the emulsion stability was inferior to soybean protein isolate and casein.Finally,the Lentinus edodes protein is applied to bread making to develop a new type of nutritious bread.The test results show that when 1%-2% of Lentinus edodes protein is added to the flour,the dough gluten network is more compact,and the produced bread has unique flavor and uniform internal pores;the hardness increases slowly during storage and the water retention is better.Good quality can still be maintained during storage.However,excessive addition of Lentinus edodes protein will have a slight adverse effect on the color and specific volume of the bread,so the optimal addition amount of mushroom protein is 1%-2%.