Liquid Fermentation Process Optimization And Product Development Of Mycelium Of Birch Phellinus Igniarius

Phellinus igniarius is a rare medicinal fungus,whose fruiting body and mycelium contain similar active ingredients,which work remarkably well in improving human immunity,antioxidant,lipid-lowering and anti-tumor.At present,the growth cycle of the fruiting bodies is long,difficulty in cultivation,and its market is undersupplied.Therefore,liquid fermentation technology is used to realize the cultivation of short-cycle,low-cost and high-yield mycelium,so as to alleviate the problem of shortage of the fruiting body resources.In this paper,taking the birch Phellinus igniarius of Changbai Mountain as the research object.Firstly,the liquid fermentation process of the mycelium was optimized,and then the relevant quality standards of mycelium were formulated to promote the healthy development of Phellinus igniarius industry.Finally,using the mycelium as raw material to develop a teabag product which have antioxidant properties.The main research contents and results of the full paper are as follows:1.Taking the yield of flavonoids in mycelium per unit volume of culture medium as the index,the culture medium was optimized by single factor experiment and orthogonal optimization experiment,and single factor experiment and response surface optimization experiments were carried out to optimize culture conditions.Finally,the optimal medium composition of the mycelium was determined as follows:glucose:sucrose（1:1）composite carbon source:30 g/L,bran:yeast extract（1:1）composite nitrogen source:5.0 g/L,Mg SO₄1.5 g/L,KH₂PO₄1.5 g/L.The optimal culture conditions were as follows:temperature 28°C,rotational speed 160 r/min,pitching rate 12%,the volume of medium added in mid-term is 15 m L.The above results were fine-tuned and verified,and the actual flavonoid yield was（60.14±2.97）mg/L,It is nearly 2.5 times better than the pre-optimization result.2.Research on the quality standards of the mycelium,mainly including the traits and microscopic identification,the determination of physical and chemical components,harmful heavy metals and the content of main active ingredients.The following standards are formulated according to the results:the moisture content of the mycelium is not more than 12%,the total ash content is not more than 4%,the acid insoluble ash content is not more than 1.3%,the water-soluble extract is not less than 25%,and the alcohol-soluble extract is not less than 22%;The results of hazardous heavy metal elements contents are as follows:Hg<0.01 mg/kg,As<0.04mg/kg,Pb 0.19 mg/kg,Cd 0.15 mg/kg,all of which meet the hazardous heavy metal content standards of edible fungus products formulated in GB2762—2017;The content of polysaccharides in the mycelium is not less than 1.2%,the content of flavonoids is not less than 0.6%,and the content of triterpene is not less than 0.2%.3.Combine the mycelium with other edible and medicinal Chinese herbal medicines,develop a mixed teabag product.Taking the sensory score of tea soup as the index,the optimal composition of the teabag was determined by single factor experiment and orthogonal optimization experiment.Taking the DPPH free radical scavenging rate of tea soup as the index,and the optimal brewing conditions of the teabag were determined by single factor experiment and response surface experiment.The moisture,total ash,water-soluble extract and microbial indexes of the product were also determined.The results showed that the optimal ingredients of the teabag were as follows:red date 2.0 g,mycelium 0.2 g,tangerine peel 1.0 g,licorice 0.3 g.The corresponding sensory score is（84.43±1.25）.The optimal brewing temperature76℃,brewing time 7.2 min,brewing water 140 m L.Under these conditions,the scavenging ability of DPPH·of the tea soup can reach（91.13±2.50）%.In addition,the moisture content of the teabag was（5.84±0.89）%,ash content was 4.50±0.93)%and water-soluble extract content was（38.43±1.92）%,all of the indexes meet the requirements of the GB/T 24690-2018"Tea Bag"standard and the microbiological indexes meet the requirements of the GB.16740-2014.