| Apple pomace, the residue left from juice extraction, is about 25% of fresh apple weight. Approximately several million tons of apple pomace are produced annually in China, more than 0.6 million tons in Shaanxi province which is the biggest apple production base. Because of the high proportion of organic acids and very little protein (about 6% in dried apple pomace), apple pomace cannot be used as feedstuff directly. At present, almost all of apple pomace is discarded. When fermented by natural microorganism, it emits bad niff and causes a serious environmental problem. This restricts the development of apple juice production. Using biotechnology and fermenting apple pomace for feeding protein is a practical way. It not only offers protein for livestock breeding, but also helps solve pollution problems. At the same time, interrelated technology of solid-state fennentation (SSF) was studied in this paper, it will perfect the theory of fermentation, and help develop other pomaces, lees and straws.Using laser radiation equipment made by us, better strains for producing feeding protein from apple pomace and their optimal mixed proportion of inoculation were obtained. Preferable method for fresh apple pomace drying was confirmed, which would offer assurance for industrial treatments. Through single factor experiments and orthogonal experiments, nitrogen source and optimal substrate were studied, and concentrated effect and efficacy evaluation of nitrogen source were analyzed in the process of fermentation.Based on the optimized technological conditions of single solid-state fermentation (SSF), two new fermentations, liquid-solid-state fennentation (LSSF) and solid-solid-state fermentation (SSSF), were introduced in this paper. After technical and economical analysis on these three fermentation technologies, the results indicate that mixed strains have strong intergrowth and synergistic capabilityand grow quickly in the process of liquid-solid-state fermentation (LSSF). Moreover inoculum's concentration is big, fermentation time is short, utilization ratio of equipments and protein content in products are all high, and it is very good for the modern industrial production. But solid-solid-state fermentation (SSSF) is the most simple and needs lower cost of investment and production, it is very convenient to be applied widely, and solves the problem of apple pomace.Through elements analysis and determination of ash and combustion heat, molecular formulas and formation enthalpies of materials and products, which are all considered as pure substances, were figured out, and then metrology equation and total thermodynamic effect of the whole fermentation process were gained. Subsequently, according to the results of optimum fitting to experimental data, mathematic model and kinetic equation were obtained. Using the above kinetic equation and its differential coefficient, different extremum and corresponding times were deduced to analyze the inner change law of the fermentation process and optimize the technological parameters. FTIR was used in this work to study materials and products of the fermentation, after explained relationship between characteristic absorption peak and component change, a method, using IR to scout and observe the fermentation process, will be established in the future work.At last, green cyclic process of apple resource was introduced in this paper, which met the needs of continuable development. The further work was considered and designed to complete the cyclic process, and made the Shaanxi apple resource towards the way to green cyclic development. |
PDF Full Text Request