Flour Additives
Most tortilla meals evaluated by Waniska et al. (2004) were bleached. Oxidizing agents or bleaches are used to visibly remove natural yellow flour pigments. Some flour oxidants also act on the sulfhydryl groups in flour proteins, affecting their function and causing "ripening". However, some oxidizing agents act only as bleaching agents and do not cause the flour to ripen, while others act only as ripening agents. For example, benzoyl peroxide is strictly a bleaching agent, while azodicarbonamide (ADA) is a azodicarbonamide ripening agent. Chlorine and chlorine dioxide are examples of oxidizing agents which are both bleaching and strong curing agents and are usually only used in soft wheat flour.
Oxidants like ADA that act on protein function tend to make dough tough. The average protein content of flours containing ADA was similar to the average for all flours, but their average mixer peak resistance was significantly higher (Waniska et al., 2004). As a result, they produced tortillas with a smaller diameter and longer shelf stability than the average for all flours. Correlation analyzes showed that dough and tortilla properties were significantly affected by protein quality, but not protein content. This suggests that oxidizing agents like ADA alter the functionality of flour proteins, so flour performance cannot be based solely on protein content. Therefore, a more reliable predictor of commercial flour performance is a functional test, such as the Mixograph method.
Oxidizing agents are compounds added to dough formulations to alter the properties of the gluten matrix (Table 7.2). These changes are often referred to as "enhancing". Generally, this means that by promoting the formation of disulfide bonds between glutenin subunits, the dough becomes more elastic and its gas holding capacity is enhanced. Commonly used oxidizing agents include azodicarbonamide, calcium peroxide, and ascorbic acid. Others approved for use include potassium iodate and calcium iodate. Until recently, potassium bromate was a very common oxidizing agent in bakery products until recently it was classified as a carcinogen. This status affects its popularity and consumer acceptance. Potassium bromate is unique in that it is slow acting and its strengthening effect occurs later in dough processing than other oxidizing agents. Thus, bromate can be worked on before the dough hardens and becomes difficult to handle. Significant efforts have been made to find alternatives to bromate, but no universal alternative has been identified to date.
Oxidizing agents – compounds added to dough to promote disulfide bond formation. Oxidizing agents have a strengthening effect on doughs, making them more elastic and less extensible.