Study On Isolation And Identification Of Microbial Bee Bread And Optimization Of Liquid Fermentation Conditions By Response Surface Method

Bee bread is the bee pollen collected in the honeycomb nest after being crushed and sealed with beeswax.Under the action of microorganisms,the bee food is formed after a certain period of fermentation.In this study,natural bee grain was used as a reference to isolate and study the microbes fermented by bee pollen in bee grain,and to screen the strains with excellent fermentation performance,and the fermentation experiments were carried out in a small liquid fermenting tank.Finally,the nutritional components of artificial bee grain and natural bee grain were preliminarily compared.The main results are as follows:(1)using natural bee grain as a reference to separate and study the microorganisms contained in bee grain,it is confirmed that it belongs to Aspergillus Aspergillus.versicolor,Aspergillus oryzae Aspergillus.oryzae,Rhodotorula of Rhodotorula,Lactobacillus.rhamnosus of Lactobacillus casei,Lactobacillus brucellus Lactobacillus.buchneri;plant milk rod Bacteria Lactobacillus.Plantarum;Lactobacillus acidophilus Lactobacillus.acidophilus;Lactococcus lactis Lactococcus.garvieae;Bacillus megigantobacilli Bacillus.megaterium.(2)the acid producing activity of 5,6,7,8,9,10 and 12 lactic acid strains isolated and identified was tested.The acid producing activity of the bacteria 8 was the strongest by measuring the pH value of the culture medium and the titratable acid.When the bacteriostasis activity of lactic acid bacteria was measured,7 strains of lactic acid bacteria had certain inhibitory effect on Staphylococcus aureus;the lactic acid bacteria outside 6 had obvious inhibitory effect on Escherichia coli,and the other bacteria 7 showed bacteriostasis activity to Bacillus subtilis,while the other strains had no inhibitory effect on them.The bacteriostasis activity of the indicative fungi is specific,the bacteria 6,7,8 and 12 have strong inhibitory effect on beer yeast,and the other strains have not detected the bacteriostasis activity,and the bacteria 5,6,8 and 10 have inhibitory effect on Candida.The acid producing activity and bacteriostasis activity of lactic acid bacteria were synthesized.The strain 8 was selected as the lactic acid strain with excellent fermentation performance,and the optimum growth temperature of the strain was 35,and the pH value was 6.(3)design experiments to optimize the fermentation conditions of lactic acid bacteria in a small liquid fermentation tank.The results showed that the inoculation mode of lactic acid bacteria was lactic acid bacteria fermentation.On the basis of single factor test results,the response surface analysis was carried out on the liquid fermentation process of bee grain.By solving the multiple regression equations of the number of lactic acid bacteria(107 cfu/g,Y1)and sensory score(Y2),the optimum extraction was obtained by the multiple regression equations of the volume of liquid(A),the inoculation amount(B)of lactic acid bacteria(B),the fermentation temperature(C)and the stirring speed(D).The conditions were as follows: the liquid volume(v/m)was 8.4,the Lactobacillus inoculation volume(v/v)was 10.3,the fermentation temperature was 33 C,the agitation speed was 436 r/min,and the fermentation period was 4 days.(4)to judge the nutritional value of artificial bee grain and natural bee grain by measuring reducing sugar,total sugar,crude fat,crude protein,alpha amino acid and lactic acid,the total sugar of artificial bee grain after fermentation was increased by 22.45%,crude fat decreased by 0.58%,crude protein increased by 2.18%,amino acid total increased by 0.49%,and lactic acid increased by 0.18 g/100 G From this,we can see that after the fermentation of pollen,various nutritional components have changed greatly.SDS-PAGE electrophoresis was used to find that the relative molecular weight of the original pollen was 23 kD after the fermentation was used as bee grain.It was reported that the allergens were some of the acidic protein of some relative molecular mass of 20 kD~40 kD,so that the allergenic protein of the pollen may be eliminated to some extent.But we need further experiments in animals and human bodies to verify it.