The influence of raw material composition on the puffing rate: for example, for grains, the influencing factor is the total amylose content. In the processing of puffed rice, the effect of moisture content on the puffing rate is very important. The puffing rate of the dehulled rice initially increases with the increase of water content; after reaching a certain level, it decreases with the increase of water content.
- Processing technology: gelatinization temperature of starch, addition of edible oil to grains, etc.
- Extrusion equipment: ① Screw: During the pressurization process, the pressure, shear force and heating temperature of the equipment all have an impact, but a relatively important factor is the length and diameter of the screw, and secondly, the rotation speed of the screw also plays a key role. The higher the rotation speed, the higher the temperature, the lower the residence time, the lower the torque, the higher the puffing degree, and the lighter the color of the product. ② Feeding: For the same mold, under the condition that other conditions remain unchanged, if the feeding is increased, the pressure will increase, the expansion degree will become lower, and the color will become darker.
In the process of puffed food processing, the direct cause of unqualified puffed food is generally the problem of seasoning. Due to the particularity of the puffed food processing technology, it has to undergo high temperature or even high pressure, and the semi-finished products have no problem in terms of microbial indicators. Quality of products. Secondly, in the processing of puffed small food, due to the addition of inappropriate food additives, such as aluminum-containing leavening agents, the aluminum content of the product will be too high. Some come into contact with alloys containing lead and tin, which will vaporize at high temperatures and may contaminate puffed food. There is also a source of aluminum that has not attracted widespread attention, that is, synthetic food colorings, colorants prepared by precipitation of their aluminum lake water-soluble pigments on alumina. In addition, there are still some problems such as extremely poor hygiene conditions in some processing points, and sour deterioration of some foods under bad conditions.
Shanghai HG Food Machinery Co.,ltd., whose head factory was built in 1970s. During its nearly 40 years’ experience an designing and manufacturing in food machine, it now has developed into an enterprise with strong technical power, great reputation in local and global market. HG enterprise now owns 4 machine processing factories, 1 food laboratory factory, 1 trading company, and 1 poly-tech university with an annual construction area of 50000 square meters and annual output value of 500 million RMB.HG group has passed the ISO9001:2008\CE\SGS certificates and has scored more than 300 patents and awards,making it one of the few large-scale private high and new tech enterprise in Shanghai, or even China.