Lotus root is a perennial plant of Nymbiaceae, starch is its main nutritional component, the content is 10% ~20%. China is rich in lotus root resources. Lotus root is processed to make starch, which can be used as an important raw and auxiliary material in food processing industry, and has great resource advantages and development prospects.
The advantages of lotus root starch microwave drying equipment:
- The lotus root starch large-size microwave drying equipment has the advantages of short drying time and high efficiency. The time of the hot-air drying lotus root starch is the longest, the microwave drying time is the shortest, and the high-efficiency energy-saving.
- The large microwave dryer of Lotus Root has high brightness and natural color.Microwave has advantages of fast heating speed, heat transfer from inside to outside, strong penetration, high energy utilization rate, which can shorten drying time and keep the original color and scent of the material.
- The morphology of lotus root after drying by large microwave drying equipment is better.Under the condition of hot air drying, the surface of some lotus root starch particles is rough, there are obvious pits, and there are agglomeration and cracks between the particles. Infrared dry starch, the surface of particles is very rough, the agglomeration of particles is serious, and the appearance quality is poor. The shape of the two dry starch particles is irregular.
The starch dried by vacuum microwave did not gelatinize and melt, the particles were complete, the outline was clear, the surface was smooth, and very few particles had slight pits on the surface. The shape of starch particles dried by microwave is regular, the overall structure of large particles is elliptical, and the small particles are spherical, which can maintain the structural characteristics of starch particles.
- The viscosity of lotus root starch dried by large microwave drying machine is small and widely used.The viscosity of vacuum microwave drying starch is lower than that of the other three drying methods. The reason is that in the early stage of starch paste heat preservation, starch particles collide with each other after water absorption and expansion, friction and extrusion, the degree of association between starch molecules is increasing, the hydrogen bond between molecules is closer, the microcrystal bundles in molecules become larger, the shear and fracture resistance are enhanced, and the viscosity is increased. When the viscosity reaches the maximum, with the prolongation of retention time, starch continues to absorb water and expand, and the volume of starch paste increases, which also increases the average volume occupied by each molecule, and the viscosity of internal molecules decreases due to the weakening of intermolecular interaction, which is often used as thickener and nutritional intensifier in industry and food.
- The starch paste has low transparency and high amylose content.Transparency is the external manifestation of starch paste, which affects the sensory evaluation of starch lotus root and the acceptability of consumers and markets. Because of the large flow radius of high content amylopectin in aqueous solution, the steric hindrance of the solution is large, the molecular dispersion is uniform, the light can produce more reflection and scattering when passing through starch paste, the transparency is low, the mobility and dispersion are good. Therefore, lotus root starch treated by large microwave drying equipment has low transparency, good mobility and molecular dispersion, and is more suitable as color protector, anti-binding agent and so on.
When treating starch, lotus root starch large microwave drying equipment has short drying time, high starch brightness, natural color, complete starch particles, no agglomeration, clear outline, smooth surface, good appearance, low water evolution rate of starch and good freeze-thaw stability. Comprehensive comparison, lotus root starch drying time-consuming, starch appearance and properties, lotus root starch industry continuous microwave dryer drying method is better than other methods, is worthy of recommendation.