In recent years, a series of snack foods have been produced at home and abroad by using puffing machinery and equipment, which are characterized by crispness, crispness, and ease of digestion and absorption, so they are favored by consumers.
Extrusion and screw extrusion.
First of all, from the puffing machinery perspective of process flow, raw material mixing – cooking and stirring – rolling – drum – cooling, aging, cutting and shaping – primary drying – storage – secondary drying – frying/baking/frying with seasoning – packaging – finished products. According to the process flow, the equipment is arranged such as mixer, skin press, cooler, skin curler, aging room, molding machine, primary dryer, secondary dryer, fryer and flavoring machine.
The puffing effect of high temperature puffed food depends on many aspects. For example, puffing machinery the more amylopectin content in starch raw materials, the better the expansion; The content and lattice degree of internal moisture in semi-finished products; In the heating and drying stage of semi-finished products, the bulking agent is added, and after partial decomposition, a very fine porous structure is formed in the semi-finished products. The remaining bulking agent is decomposed by heat to produce gas. The two cooperate to make the products reach a fully expanded bulking structure.
Raw material ratio. The raw materials are mainly starch and flour. Among the starches, the higher the amylopectin content, the better. The ratio of amylopectin and the degree of expansion of the commonly used raw materials decreased in turn. Ranking the common raw materials in the market, glutinous rice has a good expansion degree of Z, followed by potato starch, cassava starch, glazed rice, corn starch and stem rice. The flour with medium gluten content (about 25% wet gluten content) is better. The content of gluten is too high, and the shrinkage elasticity of gluten makes the product not easy to expand, resulting in collapse and stiffness; The gluten content is too low, and the dough is easy to break when rolling.
Product packaging. The puffing machinery is packaged with linear low-density polyethylene film or aluminum foil and stored at room temperature for 10 weeks. Measure the brittleness and moisture content of the product every 2 weeks. The results showed that the quality of packaged extruded soybean food did not change after 6 to 8 weeks at room temperature.
