The Study Of The Wet Camellia Cake Fermented Produce Of Protein Feed

Wet camellia cake is the residue after extracting oil in production with the aqueous-enzymatic technology using the seeds of Camellia oleifera Abel. The wet camellia cake is abandoned in factories which cause resources waste and environment pollution. This thesis focused on utilizing the wet camellia cake with the solid-state fermentation to produce bacterial protein feed, studying of fermentation processing, and analyzing the fermentation products.The main results are as follows.1. Principal components analysis of wet camellia cakeThe main composition of wet camellia cake was determined. Its crude protein (desiccate) and camellia saponin content were1%～3%and11%～14%, about4%of the total sugar and16%crude cellulose.2. Strain screeningSix strains of Yeasts, one strain of Trichoderma viride, eight strains of Aspergillus oryzae, two strains of Penicillium glaucum, two strains of Mucor mucedo, one strain of Rhizopus and one strain of Aspergillus niger were adopted in this study. The selection of single strain was conducted through prescreening and rescreening of the solid-state fermentation. According to the results, the amount of crude protein from a single strain fermentation is29.17%for As331of Aspergillus oryzae,25.45%for Pe40of Penicillium glaucum,23.61%for M06of Mucor mucedo,27.51%for Aspergillus niger H, and20.95%for Candida tropicalis.These selected five strains were used for various combination fermentation experiments. The results showed that the optimal fermentation combination was Candida tropicalis, Aspergillus oryzae As331, Penicillium glaucum Pe40, which yielded the highest crude protein content (34.93%). To determine the best inoculation proportion of mixed bacteria from these three strains, the fermentation experiments with different inoculation proportions were conducted, which were1:2(0.5),1:1(1.0),3:2(1.5),2:1(2.0), and5:2(2.5). respectively. The results showed that the most suitable proportion was1:2and its content of crude protein was34.38%. 3. Optimization of mixed strains culture conditionsResponse surface experiment of four factors at three levels was conducted. The factors and levels were as following:the amount of inoculation (4%,6%, and8%), the amount of wheat bran (10%,15%, and20%), the fermentation temperature (28℃,30℃, and32℃), the fermentation time (2.5days,4days, and5.5days). The results showed that the optimal condition of the fermentation was as following:6%of the amount of inoculation,16%of the amount of wheat bran,30℃as the fermentation temperature, and5days of the fermentation time. At this condition, the crude protein content in the fermented camellia cake was35.88%.4. Analysis of the fermentation products nutrition componentThe enlarged fermentation was carried out with the optimal fermentation condition. The fermented products were dried and nutrition component of products were analyzed. The results showed that the content of crude protein was increased from22.54%to39.34%(the rate of increase was74.53%). The content of raw cellulose was decreased from46.18%to42.12%(the rate of decrease was8.79%). Seventeen amino acids were increased to various degrees. The one increased significantly was tyrosine, followed by glutamic acid, leucine, alanine and lysine.