The leavening agent can be divided into two categories: biological leavening agent and chemical leavening agent.
1. Biological leavening agent (yeast)
Yeast is a very important leavening agent in pasta. It not only enlarges the volume of the product, but also has a sponge-like structure, and can improve the nutritional value and flavor of the noodle product.
2. Chemical leavening agent
Chemical leavening agents are formulated from edible chemicals and can be divided into a single leavening agent and a composite leavening agent.
(1) Single leavening agent A single leavening agent is usually NaHCO3 and NH4HCO3, both of which are basic compounds. Na2CO3, which is decomposed by NaHCO3, will react with oil at high temperature to produce saponification reaction, which will result in poor quality, impure taste, increased pH, deepening of color and destruction of tissue structure. NH3HCO3 decomposed NH3 gas is easily soluble in water. The formation of NH4OH causes the product to have an odor, an elevated pH, and is highly destructive to vitamins. Therefore, NaHCO3 and NH4HCO3 should be used as much as possible. The combination of the two can reduce some defects. NH4HCO3 is usually only used in products with less moisture content, such as biscuits.
(2) Composite leavening agent The composite leavening agent is generally composed of three components: carbonates, acid salts, starches and fatty acids. The composite leavening agent can be classified according to the composition of the basic salt and the reaction rate.
