Research On Preparation Of Protein Feed By Multi-strain Fermentation With Duck Droppings

In recent years, animal husbandry in China has been developed rapidly, a large number of livestock wastes discharged directly become a major reason of agricultural environmental degradation, and has attracted public attention. Liang Tan River is not only the largest sub-basin river but also the most polluted in Chongqing City. Liang Tan River pollution is mainly farming wastewater, domestic sewage and so on, 40% of them is duck droppings pollution, the integrated control of beach River focused on duck pollution .Some studies show that the duck droppings has higher crude protein, its nutrient content is higher than corn and other feed. In some sense that duck droppings is a kind of resource instead of pollution. The duck farm in Liangtan River basin is not a source of pollution, but a huge base of raw feed materials. Accordingly, this study from the perspective of utilizing duck droppings as a resource, the best way to solve the duck droppings pollution is transforming it into feedstuff, so as to achieve waste reduction, harmlessness and resource recycle, at the same time reducing environmental pollution with economic benefits and social effects.In this study, duck droppings were used as research material, mainly used these strains– Geotrichum candidum, Aspergillus oryzae, Saccharomyces cerevisiae, Pachysolen tannophilus, Trichoderma koningii, Phanerochaete chrysosporium, which has high mycoprotein and easy to survive, as fermentation. And used Solid-state fermentation technique to systems research duck's single strain fermentation and different combinations of mixed strains fermentation product of the changes in protein content.Secondly, through the single factor experiment, examined influences of different nitrogen sources, plus supplementary material on the fermentation products of different proteins, to determine the top of the solid substrate for fermentation optimization formula。Finally put the amount of the fermentation substrate, temperature, time, water content on quality of fermented products, and initially determined the optimum conditions of fermentation.Take mixed medium protein content as contrast. Comparison of single strain fermentation results show that the crude protein of production in the higher is Phanerochaete chrysosporium, Trichoderma koningii, Geotrichum candidum;and the true protein of production in the higher is Aspergillus oryzae , Geotrichum candidum, Trichoderma koningii. Because the product of two kinds of Geotrichum candidum's fermentation nutrients content were higher. So based on it,the reserch used Geotrichum candidum as indicator bacteria, Composite strains combination fermentation. Testing show that the best combination of Geotrichum candidum, Saccharomyces cerevisiae and Aspergillus oryzae fermentation has the best effect relatively, the preliminary view that the three strains have the synergistic effect during the fermentation process. When the ratio between the three strains of the 1:1:1, inoculum 25%, had better fermentation.Through single factor test initially set up a suitable for duck solid fermentation medium optimization formula: plus accessories for the bran, and adding 1.5% ammonium sulfate. Test also systematically studied duck fermentation conditions, results showed that: the amount of matrix put, moisture, temperature, time had certain influences on the fermentation. When the laboratory capacity matrix put at 20g, duck droppings and wheat bran ratio is 80:20, temperature around 29℃and at about 48h ~ 60h period of time, duck droppings fermentation products reached the best quality.The results showed that the fermentation products of crude protein, true protein content improved to some degree under the conditions of bacteria in the optimal compound, optimum medium composition and the best fermentation, crude protein improved 20.47% to 30.14%, the increasing rate is 40.7%; true protein increased from 11.68% to 20.87%, the rate is 78.7%; crude fiber of products decreased from 18.79% to 14.61%, which the rate is 22.2%. From the characteristics of fermentation products, the fermentation products have bacterial surface layer of white membrane, matrix soft, odor removal is better and with darker wine aroma. Duck droppings fermentation has achieved the expected goal.