Critical conditions for the formation of Maillard Reaction Products (MRP) in bread: An integrative review

Bread is a food of high consumption worldwide the thermal processing causes the formation of Maillard Reaction Products (MRP). Despite the beneficial sensorial impact, MRP are implicated in harmful effects on human health. This study aimed to review data on critical preparation factors and their influence on specific MRP contents in different types of bread and identify ways to mitigate the formation of these compounds in breadmaking. Acrylamide (AA) and hydroxymethylfurfural (HMF) stood out with the highest frequency of quantification in bread. In thermal processing, the highest AA contents are related to the increase in temperature depending on the exposure time; the highest HMF contents are exclusively related to the increase in temperature (regardless of time); and FUR levels decrease depending on temperature intensity and longer exposure time. A temperature of up to 220 °C tends to form less MRP for up to 60 min of roasting. The evolution of MRP in bread is affected by the weight of the baked dough; type, composition, and refinement of flour; type of yeast/leaven; modified atmosphere equipment and technologies during baking, and essentially, thermal exposure (time x temperature). These factors can contribute to good manufacturing practice criteria for mitigating MRP in bread.