Granulation coating process for enzyme preparation

At present, the coated phytase for research and development has high activity and good thermal stability, and has been widely used in the feed industry. The preparation process is as follows: the phytase stock solution (300~1000 units/ml) obtained by fermentation of the genetic engineering bacteria is filtered and over-considered to obtain a phytase concentrate (15000~20000 units/ml). The concentrated enzyme solution is mixed with starch, water-soluble inorganic salt and organic matter in a certain ratio, uniformly kneaded into a dough shape in the processing equipment, and extruded, cut, and rounded to form small particles, and then dried by a low-temperature air stream. Screening gives enzyme particles of moderate diameter (0.2 to 1.6 mm in diameter). Finally, the suitable water insoluble matter is selected, sprayed on the surface of the particle to form an outer protective layer, and dried at a low temperature to form a coating type enzyme-containing granule. The thermal stability of the granzyme preparation is mainly affected by the type, content and ratio of the added organic matter, in addition to the structure of the enzyme protein itself.