Cellulase is of great significance in expanding the comprehensive utilization of raw materials and plant materials in the food industry, increasing the utilization rate of raw materials, purifying the environment and opening up the new energy sources.
Cellulase is of great significance in expanding the comprehensive utilization of raw materials and plant materials in the food industry, increasing the utilization rate of raw materials, purifying the environment and opening up new energy sources. The source of cellulase is very wide. Insects, microorganisms, bacteria, actinomycetes, fungi, animals, etc. can produce cellulase. At present, most of the microbial strains used to produce cellulase are filamentous fungi. Among them, the strains with strong enzyme activity are Trichoderma, Aspergillus and Penicillium. In particular, Trichoderma viride and its related strains are more typical and are currently recognized as better cellulase-producing bacteria.
Cellulases such as Trichoderma viride, Aspergillus niger and Fusarium have been prepared. At the same time, ruminants rely on rumen microorganisms to digest cellulose, so rumen juice can be used to obtain crude enzyme preparations of cellulase. In addition, tissue culture methods can also be used to obtain the desired microorganisms.
At present, the production of cellulase mainly includes solid fermentation and liquid fermentation.
The solid fermentation method uses corn and other crop stalks as the main raw material, with low investment, simple technology and low product prices. However, the solid fermentation method has fundamental defects. The cellulase produced by the solid fermentation method using straw as the raw material is difficult to extract and refine. At present, most cellulase manufacturers can only use direct drying method to pulverize to obtain solid enzyme preparation or soak in water and press filter to obtain liquid enzyme preparation. The product is rough in appearance and unstable in quality, unstable in fermentation level, low in production efficiency, easily contaminated with bacteria, and is not suitable for large-scale production.
The liquid fermentation production process is to crush the corn stalks to below 20 mesh for sterilization, and then send it to the fermentation kettle for fermentation, while adding cellulase strains. The fermentation time is about 70 hours and the temperature is below 60°C. Sterilized sterile air is introduced from the bottom of the kettle for aeration and stirring, and the fermented materials are filtered through the filter press plate and frame, ultrafiltration concentrated and spray dried to obtain cellulase products. Liquid submerged fermentation has become an important research and development direction at home and abroad due to its advantages of easy control of culture conditions, resistance to contamination of bacteria, and high production efficiency.
Adding cellulase during alcohol fermentation can significantly increase the yield of alcohol and liquor and the utilization of raw materials, reduce the viscosity of the solution, and shorten the fermentation time. There may be two reasons for cellulase to increase the wine yield: one is that part of the cellulose in the raw material is decomposed into glucose for the yeast to use. In addition, because cellulase decomposes plant cell walls, it is beneficial to the release and utilization of starch.
The application of cellulase in the malt production of the beer industry can increase the solubility of the wheat grains, accelerate the germination, reduce the single glucose content in the saccharification liquid, improve the filtration performance, and facilitate the distillation of alcohol.
After the tofu residue is treated with cellulase, it is fermented with lactic acid bacteria to produce fermented beverages with excellent nutrition and taste. The application of cellulase in fruit and vegetable juice and pollen beverages can increase the extraction rate (about 10%) of the juice and promote the clarification of the juice, make the juice transparent without precipitation, increase the content of soluble solids, and comprehensively use the peel. At present, there are reports that the citrus peel residue has been successfully enzymatically hydrolyzed to obtain a whole fruit beverage, in which 50% of the crude fiber is degraded into short-chain oligosaccharides, that is, the dietary fiber in the whole fruit beverage, which has certain health and medical value.