is bleached to remove any brown pigments and produce a bright white color. The pH of the bleached flour is between 3 and 4.5, although the optimal pH of starch gelatinization is between 3.7 and 3.9. Acidifiers are used in order to reach this pH range. The optimal flour protein content is between 3% and 4%, and must be below 4.5%. If a mixture is used, at least 20% by weight should be wheat flour. A small amount of raw wheat starch may be added to the sugar as a grinding aid. Pregelatinized starch may be added to increase the rate of starch gelatinization. One method of pregelatinization starts by heating a mixture of starch and water until a gel forms. The gel may be placed on a heated roll in a thin layer in order to dry it. Once all the water has been removed, a starch cake is left on the roll. The cake is then scraped off and pulverized to form a powder. When the pregelatinized starch powder is subjected to water, a gel forms. The pregelatinized starch increases water adsorption. This in turn increases the batter viscosity and helps retain the entrapped air while the batter is prepared and as it starts to bake. The gel is not as strong has it would be if a normal starch was mixed with water and heated. However, the combination of pregelatinized starch and starch in the wheat flour create an acceptable gel together. Typically corn starch is used, however a variety of other starches also work. A balanced chemical leavening such sodium bicarbonate, along with an acidifier is another common ingredient. When reacted together, the acidifier has the ability to release all of the carbon dioxide from the sodium bicarbonate. A variety of acidifiers can be used, including potassium bitartrate, tartaric acid, and disodium phosphate. The type of acidifier used depends on when the preferred release of CO2 is. If the release would be most beneficial when the batter is forming, citric acid would be ideal because it is fast acting. The amount of acidifier depends on which agent, such as sodium bicarbonate, is used because they have varying neutralization points. An excess acidifier is also added; however, it is not used in combination with the sodium bicarbonate. Instead it lowers the batter pH to facilitate the starch gelatinization and maintain the egg white protein foam volume in